[Federal Register Volume 59, Number 78 (Friday, April 22, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-6043]
[[Page Unknown]]
[Federal Register: April 22, 1994]
_______________________________________________________________________
Part V
Environmental Protection Agency
_______________________________________________________________________
40 CFR Part 63
National Emission Standards for Hazardous Air Pollutants for Certain
Source Categories; Final Rule
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 63
[AD-FRL 4846-2]
RIN 2060-AC 19
National Emission Standards for Hazardous Air Pollutants for
Source Categories; Organic Hazardous Air Pollutants from the Synthetic
Organic Chemical Manufacturing Industry and Other Processes Subject to
the Negotiated Regulation for Equipment Leaks
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: On December 31, 1992, the EPA proposed to regulate the
emissions of certain organic hazardous air pollutants from synthetic
organic chemical manufacturing industry (SOCMI) production processes
which are part of major sources under section 112 of the Clean Air Act
as amended in 1990 (the Act). This Federal Register action announces
the EPA's final decisions on the rule which is referred to as the
hazardous organic NESHAP or the HON.
The HON requires sources to achieve emission limits reflecting the
application of the maximum achievable control technology consistent
with sections 112(d) and 112(h) of the Act. The rule regulates the
emissions of 112 of the organic chemicals identified in the Act's list
of 189 hazardous air pollutants at both new and existing SOCMI sources
and from equipment leaks at sources in certain polymer and resin
production processes, certain pesticide production processes, and
certain miscellaneous processes as described in the Source Category
Schedule for Standards (58 FR 63941). The EPA is also finalizing
Methods 304 and 305 with the standard. These methods can be used to
demonstrate compliance with control requirements for wastewater
streams.
EFFECTIVE DATE: April 22, 1994. The incorporation by reference of
certain publications in these standards is approved by the Director of
the Office of the Federal Register as of April 22, 1994. The
information collection requirements contained in 40 CFR Part 63
subparts F, G, H, and I have not been approved by the Office of
Management and Budget (OMB) and are not effective until OMB has
approved them.
See Supplementary Information section concerning judicial review.
ADDRESSES:
Dockets. The following dockets contain supporting information used
in developing the proposed rule. Docket Number A-90-19 contains
information specific to process vents, emissions averaging and general
information used to characterize emissions and control costs for the
industry; Docket A-90-20 contains information on equipment leaks;
Docket A-90-21 contains information on storage vessels; Docket A-90-22
contains information on transfer operations; and Docket A-90-23
contains information specific to wastewater operations. Supporting
information used in developing the negotiated standard for equipment
leaks is available in Docket Number A-89-10. These dockets are
available for public inspection and copying between 8 a.m. and 4 p.m.,
Monday through Friday, at the EPA's Air and Radiation Docket and
Information Center (formerly known as the Air Docket), room M1500, U.
S. Environmental Protection Agency, 401 M Street, SW., Washington, DC
20460. A reasonable fee may be charged for copying.
FOR FURTHER INFORMATION CONTACT: Dr. Janet S. Meyer, Standards
Development Branch, Emission Standards Division (MD-13), U. S.
Environmental Protection Agency, Office of Air Quality Planning and
Standards, Research Triangle Park, North Carolina 27711, telephone
number (919) 541-5299.
SUPPLEMENTARY INFORMATION: Under section 307(b)(1) of the Act, judicial
review of NESHAP is available only by filing a petition for review in
the United States Court of Appeals for the District of Columbia Circuit
within 60 days of today's publication of this rule. Under section
307(b)(2) of the Act, the requirements that are the subject of today's
notice may not be challenged later in civil or criminal proceedings
brought by the EPA to enforce these requirements.
The following outline is provided to aid in reading the preamble to
the standards.
I. Definitions, Acronyms, and Abbreviations
A. Definitions
B. Acronyms
C. Abbreviations
II. Background
A. Development of Hazardous Organic NESHAP and Public
Participation
B. Previous Federal Register Citations and Background Documents
C. Statutory Requirements for NESHAP
III. Summary of Promulgated Rule and Significant Changes
A. Summary of Subpart F
B. Summary of Subpart G
C. Summary of Subpart H
D. Summary of Subpart I
IV. Impacts
A. Environmental Impacts
B. Energy Impacts
C. Cost Impacts
D. Economic Impacts
V. Summary of Significant Comments and Associated Changes to the
Proposed Subparts F and G
A. Selection of Source Category and Source
B. Selection of Pollutants
C. Selection of the Rule
D. Emissions Averaging
E. Compliance, Recordkeeping, and Reporting
F. Coordination with Other Clean Air Act Requirements
G. Miscellaneous Technical Comments
VI. Summary of Significant Comments and Changes to Proposed Subpart
H
A. Applicability
B. Compliance Schedule
C. Selection of Requirements
D. Recordkeeping and Reporting
VII. Administrative requirements
A. Docket
B. Executive Order 12866
C. Paperwork Reduction Act
D. Regulatory Flexibility Act
E. Review
I. Definitions, Acronyms, and Abbreviations
The following lists of definitions, acronyms, and abbreviations for
units of measure are provided to aid in reading the preamble to the
final rule. Additional definitions are provided near the beginning of
subparts F, G, H, and I.
A. Definitions
The following definitions were developed for use in preparing and
describing the final rule.
Control device means any equipment used for recovering or oxidizing
organic hazardous air pollutant vapors. Such equipment includes, but is
not limited to, absorbers, carbon adsorbers, condensers, incinerators,
flares, boilers, and process heaters. For process vents, recovery
devices are not considered control devices.
Discount factor is a specified percentage used to reduce the value
of emission credits. A discount factor of 10 percent reduces 10 Mg of
potential emission credits to 9 Mg of actual emission credits that
could be used to balance an emissions debit. For regulatory purposes, a
10 percent discount factor is represented as 0.9 in credit estimation
equations.
Emissions averaging is a means of complying with subpart G of part
63 at existing sources. Emissions averaging allows a source to create
emission credits by reducing emissions from specific points to a level
below that required by subpart G. Those credits are used to offset
emission debits from points that are not controlled to the level
required by subpart G.
Emission credits are excess emission reductions above those
required by subpart G that are used to offset emission debits in
emissions averaging.
Emission debits are increased emissions that result when a source
elects not to control a Group 1 emission point to the level required by
subpart G.
Emission point means an individual process vent, storage vessel,
transfer rack, wastewater stream, or equipment leak.
Group 1 emission point means an individual process vent, storage
vessel, transfer rack, or wastewater stream that satisfies the
applicability criteria for the control requirements of subpart G.
Group 2 emission point means an individual process vent, storage
vessel, transfer rack, or wastewater stream that does not satisfy the
applicability criteria for the control requirements of subpart G.
Halogenated vent stream or halogenated stream means a vent stream
from a process vent or transfer operation determined to have a mass
emission rate of halogen atoms contained in organic compounds of 0.45
kilograms per hour or greater.
Hazardous Air Pollutant or HAP means any air pollutant listed under
section 112(b) of the Act.
Plant site means all contiguous or adjoining property that is under
common control, including properties that are separated only by a road
or other public right-of-way. Common control includes properties that
are owned, leased, or operated by the same entity, parent entity,
subsidiary, or any combination thereof.
Reference control technology means a device or devices that can be
used to comply with the control requirements in subpart G. Subpart G
specifies the reference control technologies for each kind of emission
point and establishes a control efficiency that the devices should
achieve when being used to comply with this rule.
Very volatile hazardous air pollutant or very volatile HAP means
one of the chemicals listed in table 8 of subpart G.
Volatile organic concentration or VO concentration refers to the
concentration of organic compounds (including both hazardous air
pollutant and nonhazardous air pollutant organic compounds) in a
wastewater stream that is measured by Method 25D, as found in 40 CFR
60, appendix A.
Volatile organic hazardous air pollutant concentration or VOHAP
concentration means the concentration of an individually-speciated
organic hazardous air pollutant in a wastewater stream or a residual
that is measured by proposed Method 305.
Waste management unit means any component, piece of equipment,
structure, or transport mechanism used in conveying, storing, treating,
or disposing of any waste, including a wastewater stream or a residual.
Wastewater tanks are an example of a waste management unit.
Wastewater means organic hazardous air pollutant-containing water,
raw material, intermediate, product, by- product, co-product, or waste
material that is discharged into an individual drain system and either:
(1) contains a concentration of at least 5 parts per million by
weight total organic hazardous air pollutant and has a flow rate of
0.02 liter per minute or greater; or
(2) contains a concentration of at least 10,000 parts per million
by weight total organic hazardous air pollutant at any flow rate.
Wastewater includes process wastewater and maintenance wastewater.
B. Acronyms
------------------------------------------------------------------------
Acronym Term
------------------------------------------------------------------------
Act....... Clean Air Act.
ALAPCO.... Association of Local Air Pollution Control Officers.
ASPEN..... Advanced system for process engineering.
BACT...... Best available control technology.
BAT....... Best available technology.
BD........ Butadiene.
BID....... Background information document.
BIF....... Boilers and industrial furnaces.
CEM....... Continuous emissions monitoring.
CFR....... Code of Federal Regulations.
CMA....... Chemical Manufacturers Association.
CMPU...... Chemical manufacturing process unit.
CO........ Carbon monoxide.
CTG....... Control techniques guideline.
CWA....... Clean Water Act.
DMS....... Dual mechanical seal.
DOT....... Department of Transportation.
DRE....... Destruction and removal efficiency.
EB/S...... Ethylbenzene/styrene.
EDC....... Ethylene dichloride.
EFR....... External floating roof.
EO........ Ethylene oxide.
E.O....... Executive Order.
EPA....... Environmental Protection Agency.
Fe........ Fraction emitted.
Fm........ Fraction measured.
FR........ Federal Register.
Fr........ Fraction removed.
FTIR...... Fourier transform infrared.
HAP....... Hazardous air pollutant.
HON....... Hazardous organic national emission standards for hazardous
air pollutants.
IFR....... Internal floating roof.
LDAR...... Leak detection and repair.
LAER...... Lowest achievable emission rate.
MACT...... Maximum achievable control technology.
MIBK...... Methyl isobutyl ketone.
MR........ Mass removal (actual).
NCS....... Notification of Compliance Status.
NESHAP.... National emission standards for hazardous air pollutants.
NOX....... Nitrogen oxides.
NPDES..... National Pollutant Discharge Elimination System.
NRDC...... Natural Resources Defense Council.
NSPS...... New source performance standards.
NSR....... New source review.
OCCM...... Office of Air Quality Planning and Standards Control Cost
Manual.
OCPSF..... Organic chemicals, plastics, and synthetic fibers.
OMB....... Office of Management and Budget.
OSHA...... Occupational Safety and Health Administration.
P.L....... Public Law.
PAV....... Product accumulator vessel.
POM....... Polycyclic organic matter.
POTW...... Publicly owned treatment works.
PRA....... Paperwork Reduction Act.
PRV....... Pressure relief valve.
PSD....... Prevention of significant deterioration.
QIP....... Quality improvement program.
R&D....... Research and development.
RCRA...... Resource Conservation and Recovery Act.
RCT....... Reference control technology.
RIA....... Regulatory Impact Analysis.
RMR....... Required mass removal.
SARA...... Superfund Amendment and Reauthorization Act.
SIP....... State Implementation Plan.
SMS....... Single mechanical seal.
SOCMI..... Synthetic organic chemical manufacturing industry.
STAPPA.... State and Territorial Air Pollution Program Administrators.
TAC....... Total annual cost.
TACB...... Texas Air Control Board.
TCI....... Total capital investment.
THC....... Total hydrocarbon.
TIC....... Total industry control.
TOC....... Total organic compound.
TRE....... Total resource effectiveness.
TRI....... Toxics release inventory.
TSDF...... Treatment, storage, and disposal facility.
VHAP...... Volatile hazardous air pollutant.
VO........ Volatile organics measurable by Method 25D.
VOC....... Volatile organic compound.
VOHAP..... Volatile organic hazardous air pollutant.
------------------------------------------------------------------------
C. Abbreviations
------------------------------------------------------------------------
Abbreviation Unit of measure
------------------------------------------------------------------------
bbl............. Barrel.
BOE............. Barrels of oil equivalent.
Btu............. British thermal unit.
Btu/kW-hr....... British thermal unit per kilowatt-hour.
deg.C.......... Degrees Celsius.
deg.F.......... Degrees Fahrenheit.
gal............. Gallon.
gpm............. Gallons per minute.
hr.............. Hour.
kg/hr........... Kilograms per hour.
kPa............. Kilopascals.
kW-hr/yr........ Kilowatt-hour per year.
l/hourm2 Liters per hour per square meter.
lpm............. Liters per minute.
gal............. Gallons.
m3.............. Cubic meters.
Mg.............. Megagrams.
mg.............. Milligrams.
mg/dscm......... Milligram per dry standard cubic meter.
MW.............. Megawatts.
ppb............. Parts per billion.
ppm............. Parts per million.
ppmv............ Parts per million by volume.
ppmw............ Parts per million by weight.
psia............ Pounds per square inch absolute.
scm/min......... Standard cubic meter per minute.
TJ.............. Terajoules.
yr.............. Year.
------------------------------------------------------------------------
II. Background
A. Development of Hazardous Organic NESHAP and Public Participation
On December 31, 1992, the EPA proposed to regulate, under section
112 of the Act, the emissions of 112 organic HAP's from SOCMI processes
which are part of major sources. Following publication of the proposed
rule, two public hearings were held and 339 written comments were
received regarding the proposed rule. The EPA considered all public
comments and made appropriate changes to the provisions. The final rule
issued today represents the EPA's final decisions for the MACT standard
for the SOCMI.
A background information document summarizing and responding to
legal comments and technical comments pertaining to this rulemaking may
be obtained from either: (1) The National Technical Information Service
(NTIS), 5285 Port Royal Road, Springfield, VA 22161, telephone (703)
487-4650, or (2) the EPA Technology Transfer Network (TTN). The TTN is
an electronic bulletin board system which is free, except for the
normal long distance charges. To access the HON BID: (1) Set software
to data bits: 8, N; stop bits: 1; (2) Use access number (919) 541-5742
for 1200, 2400, or 9600 bps modems [access problems should be directed
to the system operator at (919) 541-5384]; (3) Specify TTN Bulletin
Board: Clean Air Act Amendments; and (4) Select menu item: Recently
Signed Rules.
Please refer to ``Hazardous Air Pollutant Emissions from Process
Units in the Synthetic Organic Chemical Manufacturing Industry--
Background Information for Promulgated Standards,'' and specify volume
number(s).
Volume 2A: Comments on Process Vents, Storage Vessels,
Transfer Operations, and Equipment Leaks (EPA-453/R-94-003a);
Volume 2B: Comments on Wastewater (EPA-453/R-94-003b);
Volume 2C: Comments on Emissions Averaging (EPA-453/R-94-
003c);
Volume 2D: Comments on Applicability, National Impacts,
and Overlap with Other Rules (EPA-453/R-94-003d);
Volume 2E: Comments on Recordkeeping, Reporting,
Compliance, and Test Methods (EPA-453/R-94-003e); and
Volume 2F: Commenter Identification List (EPA-453/R-94-
003f).
B. Previous Federal Register Citations and Background Documents
Previous Federal Register Notices. Previous Federal Register
notices pertaining to this rulemaking are listed below in chronological
order. Since the complete Federal Register citation and dates are
listed here, they will not be repeated throughout this notice. Where
appropriate, an abbreviated descriptive title used to refer to the
document throughout this notice is also listed.
(1) ``National Emission Standards for Hazardous Air Pollutants for
Source Categories: Organic Hazardous Air Pollutants from the Synthetic
Organic Chemical Manufacturing Industry and Seven Other Processes;
Proposed rule and notice of public hearing,'' 57 FR 62608, December 31,
1992. Proposal notice.
(2) ``National Emission Standards for Hazardous Air Pollutants for
Source Categories: Organic Hazardous Air Pollutants from the Synthetic
Organic Chemical Manufacturing Industry and Seven Other Processes;
Correction,'' 58 FR 11667, February 26, 1993. Correction notice.
(3) ``National Emission Standards for Hazardous Air Pollutants for
Source Categories: Organic Hazardous Air Pollutants from the Synthetic
Organic Chemical Manufacturing Industry and Seven Other Processes;
Reopening of public comment period and correction to Regulatory
Flexibility Act certification,'' 58 FR 53478, October 15, 1993.
Supplemental notice.
Previous Background Documents. The following is a listing of
background documents pertaining to this rulemaking. The complete title,
EPA publication number, publication date, and National Technical
Information Service [NTIS] numbers are included. Where appropriate, an
abbreviated descriptive title used to refer to the document throughout
this notice is also listed.
(1) ``Hazardous Air Pollutant Emissions from Process Units in the
Synthetic Organic Chemical Manufacturing Industry--Background
Information for Proposed Standards, Volume 1A: National Impacts
Assessment,'' EPA-453/D-92-016a. November 1992. (NTIS Number PB93-
156552) (Docket item A-90-19: III-B-1). Proposal BID Volume 1A.
(2) ``Hazardous Air Pollutant Emissions from Process Units in the
Synthetic Organic Chemical Manufacturing Industry--Background
Information for Proposed Standards, Volume 1B: Control Technologies,''
EPA-453/D-92-016b. November 1992. (NTIS Number PB93-156560) (Docket
Item A-90-19: III-B-1). Proposal BID Volume 1B.
(3) ``Hazardous Air Pollutant Emissions from Process Units in the
Synthetic Organic Chemical Manufacturing Industry--Background
Information for Proposed Standards, Volume 1C: Model Emission
Sources,'' EPA-453/D-92-016c. November 1992. (NTIS Number PB93-156578)
(Docket item A-90-19: III-B-1). Proposal BID Volume 1C.
C. Statutory Requirements for NESHAP
Section 112 of the Act requires that the EPA establish regulations
setting emission standards for categories of sources of HAP emissions.
In addition, the Act sets out specific criteria for establishing a
minimum level of control, and criteria to be considered in evaluating
control options more stringent than the minimum control level. For most
of these rules, assessment and control of any remaining unacceptable
health risk is to occur 8 years after they are promulgated. However,
for the rules required to be promulgated in the first 2 years after
enactment, EPA is not required to conduct this assessment until 9 years
after promulgation.
Specifically, section 112(c), as amended, directs the Administrator
to develop a list of all categories or subcategories of major sources
and such categories or subcategories of area sources that meet the
requirements of section 112(c)(3), emitting any of the HAP's listed in
section 112(b). Section 112(d) directs the Administrator to promulgate
emission standards for each listed category or subcategory of HAP
sources. Such standards will be applicable to both new and existing
sources and shall require:
* * * the maximum degree of reduction in emissions of the
hazardous air pollutants subject to this section (including a
prohibition on such emissions, where achievable) that the
Administrator, taking into consideration the cost of achieving such
emission reduction, and any non-air quality health and environmental
impacts and energy requirements, determines is achievable for new
and existing sources in the category or subcategory to which such
emission standard applies * * *
42 U.S.C. 7412(d)(2).
The Amendments further provide that ``the maximum degree of
reduction in emissions that is deemed achievable'' shall be subject to
a ``floor'' which is determined differently for new and existing
sources. For new sources the standards set shall not be any less
stringent than ``the emission control that is achieved in practice by
the best controlled similar source.'' For existing sources, the
standards may not be less stringent than the average emission
limitation achieved by the best performing 12 percent of existing
sources in each category or subcategory of 30 or more sources. (Smaller
categories or subcategories are limited to the average of the best
performing five sources in the category or subcategory.)
III. Summary of Promulgated Rule and Significant Changes
This section of the notice summarizes the final rule and
significant changes made in response to public comment. The rationale
for specific provisions and changes is explained in sections V and VI.
The rule consists of four subparts in 40 CFR part 63. Subpart F
provides the applicability criteria for SOCMI sources, requires that
owners and operators of SOCMI sources comply with subparts G and H, and
specifies general recordkeeping and reporting requirements. The
specific control, monitoring, reporting, and recordkeeping requirements
are stated in subpart G for process vents, storage vessels, transfer
racks, and wastewater streams, and in subpart H for equipment leaks.
Subpart I provides the applicability criteria for the non-SOCMI
processes subject to the negotiated regulation for equipment leaks and
requires owners and operators to comply with subpart H.
A. Summary of Subpart F
Subpart F lists the HAP's regulated by this rule and specifies what
is included in the SOCMI source category and thus subject to the
requirements in subparts F, G, and H. In the final rule, the EPA has
revised the procedures for determining applicability to more clearly
indicate the boundaries between processes (i.e., where one process ends
and the next begins). In addition, subpart F presents definitions and
general information on compliance, reporting, and recordkeeping
requirements that are applicable for sources subject to subparts G and
H.
1. Regulated Pollutants
Subpart F lists 112 organic HAP's that the EPA has determined may
be emitted from SOCMI processes because they are either produced as a
product or used as a reactant. The emissions of these 112 organic
chemicals are regulated by subparts F, G, and H.
2. Definition of Source Category and Source
The rule applies to chemical manufacturing process units that are:
(1) Part of a major source as defined in section 112 of the Act; (2)
produce as a primary product a SOCMI chemical listed in table 1 of
subpart F; and (3) use as a reactant or manufacture as a product, by-
product, or co-product one or more of the organic HAP's listed in table
2 of subpart F. A chemical manufacturing process unit is subject to the
provisions of subparts F, G, and H only if all of the above three
conditions are satisfied. Table 1 of subpart F is a list of 385
chemicals which defines SOCMI products that may be produced by a HAP-
emitting process.
For the SOCMI source category, a source comprises all the SOCMI
chemical manufacturing process units that are subject to the rule and
are located at contiguous or adjoining properties under common control.
Subpart F defines the SOCMI source as the collection of process vents;
storage vessels; transfer racks; wastewater and the associated
treatment residuals; and pumps, compressors, agitators, pressure relief
devices, sampling connection systems, open-ended valves or lines,
valves, connectors, and instrumentation systems in the relevant
chemical manufacturing process units. As listed above, the first four
kinds of emission points in a SOCMI source are subject to subparts F
and G. However, SOCMI equipment leaks are subject to subparts F and H.
As such, a SOCMI source is subject to three of the HON's four subparts.
3. Other Provisions
Subpart F establishes the compliance dates for new and existing
sources and requires the source be properly operated and maintained at
all times. Sources are required to develop a start-up, shutdown, and
malfunction plan which includes a description of procedures for
managing wastewaters generated during maintenance. Monitoring of
cooling water is also required to detect leaks in heat exchange
equipment. If a leak is detected, the heat exchanger must be repaired
or taken out of service.
Procedures for obtaining permission to use an alternative means of
emission reduction are included in subpart F. The applicability of the
General Provisions in subpart A to sources subject to subparts F, G,
and H is clarified. General performance test requirements are
specified, including the provision that performance tests be conducted
under maximum representative operating conditions for the process. The
General Reporting and Recordkeeping Provisions of subpart F include the
requirement that required records and reports must be maintained for 5
years, and specify where reports must be sent. Reports can be submitted
on electronic media that are compatible with the system used by the
Administrator or the State permitting authority.
B. Summary of Subpart G
1. Overview
The MACT standard for SOCMI sources is expressed as an allowable
emissions level that is determined by means of an equation specified in
subpart G. The allowable emissions level is the sum of the emissions
from all the emission points in the source that would occur after the
required emission reductions are achieved for the emission points
meeting the HON's applicability criteria (Group 1 points) through use
of reference control technologies. Although controls are not required
for Group 2 emission points, both Group 1 emission points and Group 2
emission points are included in the equation defining the source's
allowable emissions level.
Though subpart G is structured as an allowable emissions level,
there is no need for owners or operators to actually calculate
emissions estimates for every emission point at the source. Actual
emissions estimates are only required for emission points that are
included in emissions averages.
The owner or operator can utilize two methods, or a combination of
them, to demonstrate compliance with the HON. The primary method that
owners or operators will use to determine compliance with the HON is
the application of the reference control technologies (or equivalent
controls) at Group 1 emission points. This compliance approach is
described in sections 2 through 5 below. Owners or operators may also
use emissions averaging to demonstrate compliance at a limited number
of emission points. Emissions averaging is described in section 6
below. Section 7 describes the HON's recordkeeping and reporting
provisions.
2. Process Vent Provisions
A process vent means a gas stream that is continuously discharged
during the operation of the unit from an air oxidation reactor, other
reactor, or distillation unit within a SOCMI chemical manufacturing
process unit. Process vents include vents from distillate receivers and
product separators. Process vents include gas streams that are
discharged directly to the atmosphere and gas streams discharged to the
atmosphere after diversion through a product recovery device. The rule
applies only to process vents that are associated with continuous (non-
batch) processes and emit process vent streams containing more than
0.005 weight-percent HAP.
A Group 1 process vent is defined as a process vent with a flow
rate greater than or equal to 0.005 scmm, an organic HAP concentration
greater than or equal to 50 ppmv, and a TRE index value less than or
equal to 1.0. The process vent provisions require the owner or operator
of a Group 1 process vent stream to:
(1) Reduce the emissions of organic HAP using a flare;
(2) Reduce emissions of organic HAP by 98 weight-percent or to a
concentration of 20 ppmv or less; or
(3) Achieve and maintain a TRE index above 1. Performance test
provisions are included for Group 1 process vents to verify that the
control device achieves the required performance.
The organic HAP reduction is based on the level of control achieved
by the reference control technology. Group 2 process vent streams with
TRE index values between 1.0 and 4.0 are required to monitor those
process vent streams to ensure those streams do not become Group 1,
which require control. The owner or operator can calculate a TRE index
value to determine whether each process vent is a Group 1 or Group 2
process vent or the owner or operator can elect to comply directly with
the control requirements without calculating the TRE index. The TRE
index value is determined after the final recovery device in the
process or prior to venting to the atmosphere. The TRE calculation
involves an emissions test or engineering assessment and use of the TRE
equations in section 63.115 of subpart G.
The rule encourages pollution prevention through product recovery
because an owner or operator of a Group 1 process vent may add recovery
devices or otherwise reduce emissions to the extent that the TRE
becomes greater than 1.0 and the Group 1 process vent becomes a Group 2
process vent.
Group 1 halogenated streams controlled using a combustion device
must vent the emissions from the combustor to an acid gas scrubber or
other device to limit emissions of halogens prior to venting to the
atmosphere. The control device must reduce the overall emissions of
hydrogen halides and halogens by 99 percent (95 percent for control
devices installed prior to the December 31, 1992 proposal) or reduce
the outlet mass emission rate of total hydrogen halides and halogens to
less than 0.45 kg/hr. Monitoring, reporting, and recordkeeping
provisions necessary to demonstrate compliance are also included in the
process vent provisions.
3. Storage Vessel Provisions
A storage vessel means a tank or other vessel associated with a
SOCMI chemical manufacturing process unit that stores a liquid
containing one or more of the organic HAP's listed in table 2 of
subpart F. The final rule specifies assignment procedures for
determining whether a storage vessel is associated with a SOCMI
chemical manufacturing process unit. The storage vessel provisions do
not apply to the following: (1) vessels permanently attached to motor
vehicles, (2) pressure vessels designed to operate in excess of 204.9
Kpa (29.7 psia), (3) vessels with capacities smaller than 38 m\3\
(10,000 gal), (4) wastewater tanks, and (5) vessels storing liquids
that contain organic HAP's only as impurities. An impurity is produced
coincidentally with another chemical substance and is processed, used,
or distributed with it.
The EPA is not taking final action at this time regarding
provisions for storage vessels of 76 m\3\ (20,000 gallons) to 151 m\3\
(40,000 gallons). The reason is that, through a separate Federal
Register notice, the EPA is soliciting additional public comment
regarding the appropriate interpretation of the language in section
112(d)(3)(A) of the Act concerning establishment of the MACT floor and
the effect of that interpretation on the control requirements for these
storage vessels. The EPA intends to evaluate the public comments
received in response to that action promptly and intends to proceed to
take final action on provisions for storage vessels of 76 m\3\ to 151
m\3\ within 90 days of the publication of the separate notice.
The storage provisions require that one of the following control
systems be applied to Group 1 storage vessels: (1) An internal floating
roof with proper seals and fittings; (2) an external floating roof with
proper seals and fittings; (3) an external floating roof converted to
an internal floating roof with proper seals and fittings; or (4) a
closed vent system with a 95-percent efficient control device. The
storage provisions give details on the types of seals and fittings
required. Monitoring and compliance provisions include periodic visual
inspections of vessels, roof seals, and fittings, as well as internal
inspections. If a closed vent system and control device is used, the
owner or operator must establish appropriate monitoring procedures.
Reports and records of inspections, repairs, and other information
necessary to determine compliance are also required by the storage
provisions. No controls are required for Group 2 storage vessels.
4. Transfer Operations Provisions
Transfer operations are defined as the loading of liquid products
that are on the list of organic HAP's in subpart F from a transfer rack
into a tank truck or railcar. Transfer rack means the collection of
loading arms and loading hoses at a single system that is assigned to a
SOCMI chemical manufacturing process unit and is used to fill tank
trucks and railcars with liquid products that are on the list of
organic HAP's in subpart F. Transfer rack includes the associated
pumps, meters, shutoff valves, relief valves, and other piping and
valves necessary to load tank trucks or railcars. The transfer
provisions do not apply to the loading of liquid organic HAP's at an
operating pressure in excess of 204.9 Kpa (29.7 psia); loading of
marine vessels; racks loading liquids that contain organic HAP's only
as impurities; or racks loading liquid organic HAP's if emissions are
returned to a storage vessel in a vapor balancing system.
The transfer provisions require control of Group 1 transfer racks
to achieve 98-percent organic HAP reduction or an outlet concentration
of 20 ppmv. Combustion devices or product recovery devices may be used
to comply with this requirement. Alternatively, vapor balancing systems
may be used.
The transfer provisions include design specifications for vapor
collection systems. Specifically, vapor collection systems are required
to route the organic vapors to a control device or to a vapor balancing
system and are required to operate without detectable emissions. In
addition, the provisions require that liquid organic HAP's be loaded
only into DOT-certified vehicles or vehicles that have been determined
to be vapor tight according to Method 27 of 40 CFR part 60, appendix A.
Group 1 halogenated streams controlled using a combustion device
must vent the emissions from the combustor to an acid gas scrubber or
other device to limit emissions of halogens, prior to venting to the
atmosphere. The control device must reduce the overall emissions of
hydrogen halides and halogens by 99 percent or reduce the outlet mass
emission rate of total hydrogen halides and halogens to less than 0.45
kg/hr.
Initial performance tests of control device efficiency are required
for racks loading at least 11.8 million liters per year. Design
evaluations are allowed in other cases. Monitoring, reporting, and
recordkeeping provisions are specified. Controls are not required for
Group 2 racks.
5. Wastewater Provisions
The final rule applies to any organic HAP-containing water, raw
material, intermediate, product, by-product, co- product, or waste
material that exits any chemical manufacturing process unit equipment
and has either (1) a total volatile organic HAP concentration of 5 ppmw
or greater and a flow rate of 0.02 lpm or greater; or (2) a total
volatile organic HAP concentration of 10,000 ppmw or greater at any
flow rate. ``Wastewater,'' as defined in Sec. 63.101 of subpart F,
encompasses both maintenance wastewater, which is regulated by subpart
F, and process wastewater, which is regulated by subpart G. The process
wastewater provisions in subpart G also apply to organic HAP-containing
residuals that are generated from the management and treatment of Group
1 wastewater streams. Examples of process wastewater streams include,
but are not limited to, wastewater streams exiting process unit
equipment (e.g., decanter water, such as condensed steam used in the
process), product tank drawdown, feed tank drawdown, and residuals
recovered from waste management units. Examples of maintenance
wastewater streams are those generated by descaling of heat exchanger
tubing bundles, cleaning of distillation column traps, and draining of
pumps into an individual drain system.
In the final rule, an owner or operator may determine the VOHAP
concentration and flow rate of a wastewater stream either (1) at the
point of generation; or (2) downstream of the point of generation. If
wastewater stream characteristics are determined downstream of the
point of generation, an owner or operator must make corrections for
losses by air emissions; reduction of VOHAP concentration or changes in
flow rate by mixing with other water or wastewater streams; and
reduction in flow rate or VOHAP concentration by treating or otherwise
handling the wastewater stream to remove or destroy HAP's. An owner or
operator must determine whether a wastewater stream is a Group 1 or
Group 2 wastewater stream by determining the flow rate and VOHAP
concentration for the point of generation by (1) sampling; (2) using
engineering knowledge; or (3) using pilot-scale or bench-scale test
data. An owner or operator who elects to use the process unit
alternative in Sec. 63.138(d) or the 95-percent biological treatment
option in Sec. 63.138(e) is not required to make a Group 1/Group 2
determination. Both the applicability determination and the Group 1/
Group 2 determination must reflect the wastewater characteristics
before losses due to volatilization, a concentration differential due
to dilution, or a change in VOHAP concentration or flow rate due to
treatment.
To provide greater flexibility to owners or operators, the EPA has
added to the final rule an additional option in Sec. 63.144 of subpart
G for determining applicability in lieu of a Group 1/Group 2
determination. This option allows an owner or operator to designate a
wastewater stream or mixture of wastewater streams to be a Group 1
wastewater stream without actually determining the flow rate and VOHAP
concentration for the point of generation. This option helps those
SOCMI plants that already have emission suppression systems in place
from the point of generation to a location downstream. Using this
option, an owner or operator can simply declare that a wastewater
stream or mixture of wastewater streams is a Group 1 wastewater stream
and that the emissions from the stream(s) are controlled from the point
of generation through treatment. An owner or operator is required to
determine the wastewater stream characteristics (i.e., VOHAP
concentration and flow rate) for the designated Group 1 wastewater
stream in order to establish the treatment requirements in Sec. 63.138.
Controls must be applied to Group 1 wastewater streams, unless the
source complies with the source-wide mass flow rate provisions of
Sec. 63.138(c)(5) or (c)(6) of subpart G; or implements process changes
that reduce emissions as specified in Sec. 63.138(c)(7) of subpart G.
Control requirements include (1) suppressing emissions from the point
of generation to the treatment device; (2) recycling the wastewater
stream or treating the wastewater stream to the required Fr values for
each HAP as listed in table 9 of subpart G; (3) recycling any residuals
or treating any residuals to destroy the total combined HAP mass flow
rate by 99 percent or more; and (4) controlling the air emissions
generated by treatment processes. While emission controls are not
required for Group 2 wastewater streams, owners or operators may opt to
include them in management and treatment options.
Suppression of emissions from the point of generation to the
treatment device will be achieved by using covers and enclosures and
closed vent systems to collect organic HAP vapors from the wastewater
and convey them to treatment devices. Air emissions routed through
closed-vent systems from covers, enclosures, and treatment processes
must be reduced by 95 percent for combustion or recovery devices; or to
a level of 20 ppmv for combustion devices.
The treatment requirements are designed to reduce the HAP content
in the wastewater prior to placement in units without air emissions
controls, and thus reduce the HAP emissions to the atmosphere. The
required Fr values in table 9 of subpart G are based on steam
stripping. The final rule provides several compliance options,
including percent reduction, effluent concentration limitations, and
mass removal.
For demonstrating compliance with the various requirements, owners
or operators have a choice of using a specified design, conducting
performance tests, or documenting engineering calculations. Appropriate
compliance, monitoring, reporting, and recordkeeping provisions are
included in the regulation.
6. Emissions Averaging
Under subpart G, only owners or operators of existing sources may
use emissions averaging. A change to the rule prohibits new sources
from using emissions averaging to comply with the rule. Any process
vents, storage vessels, or transfer racks in the source can be included
in an emissions average. However, only wastewater streams that are not
treated in a biological treatment unit are eligible for emissions
averaging. Equipment leaks are regulated under a separate subpart and
are also not eligible for emissions averaging.
a. Credit/Debit System. In general, the system for accumulating and
quantifying credits and debits remains the same as described at
proposal. The owner or operator must identify all the emission points
that would be included in an emissions average and estimate their
allowable and actual emissions using the reference efficiencies of the
reference control technologies for each kind of emission point.
For each Group 1 point, the allowable emissions level is the
emissions remaining after application of a reference control
technology. As a result, all Group 1 emission points that are not being
controlled with the reference control technology or a control measure
achieving an equivalent reduction are emitting more than their
allowable emissions. These points are generating emission ``debits.''
Emission debits are calculated by subtracting the amount of emissions
allowed by the standard for a given emission point from the amount of
actual emissions for that point. If a Group 1 emission point is
controlled by a device or a pollution prevention measure that does not
achieve the control level of the reference control technology, the
amount of emission debits will be based on the difference between the
actual control level being achieved and what the reference control
would have achieved. Equations for calculating debits are provided in
Sec. 63.150 of subpart G.
The owner or operator must control other emission points to a level
more stringent than what is required for that kind of point to generate
emission ``credits.'' Emission credits are calculated by subtracting
the amount of emissions that actually exist for a given emission point
from the amount of emissions that would be allowed under subpart G, and
then applying a 10-percent discount factor. If credits are generated
through the use of a pollution prevention measure, no discount factor
is applied. These provisions for a discount factor were added for the
final rule. Equations for calculating credits are also provided in
Sec. 63.150 of subpart G. To be in compliance, the owner or operator
must be able to show that the source's emission credits were greater
than or equal to its emission debits.
Credits may come from:
(1) Control of Group 1 emission points using technologies that the
EPA has rated as being more effective than the appropriate reference
control technology;
(2) Control of Group 2 emission points; and
(3) Pollution prevention projects that result in control levels
more stringent than what the standard requires for the relevant point
or points.
A reference control technology cannot be used to generate credits
beyond its assigned efficiency. For a new control technology or work
practice, either the EPA or the permit authority must determine its
control efficiency before it can be used to generate credits.
b. Compliance. The rule requires that emissions averaging plans be
reviewed as part of a source's Implementation Plan or operating permit
application. The controls in the averaging plan would then be cited in
a source's Implementation Plan or operating permit. Thus, to show
compliance using emissions averaging, the owner or operator must prove
both:
(1) The appropriate controls have been applied and maintained; and
(2) That the amount of emission credits and debits meet certain
quarterly and annual requirements.
c. Significant Changes. Significant changes were made to the
emissions averaging provision. One change is that the number of
emission points that can be included in an average has been limited to
no more than 20 points or 25 points if pollution prevention is used.
Another notable addition is the requirement that sources must
demonstrate that their emissions average will not result in greater
risk or hazard than compliance without averaging. Also, State or local
agencies have been granted the discretion to not include emissions
averaging in their implementation of the rule without having to go
through the Sec. 112(l) rule delegation process. Summaries of
significant comments and associated changes are discussed in section
V.D of this preamble. All comments regarding emissions averaging are
summarized and responded to in the BID, volume 2C.
7. Recordkeeping and Reporting
The rule requires sources complying with subpart G to keep records
and submit reports of information necessary to document compliance.
Records must be kept for 5 years. For emission points where continuous
monitoring is required, the final rule requires retention of hourly
average data values rather than the 15-minute average values specified
in the proposed rule. However, 15-minute values must be retained for
operating days when the daily average value of the monitored parameter
is outside the permitted range.
The following five types of reports must be submitted to the
Administrator: (1) Initial Notification, (2) Implementation Plan (if an
operating permit application has not been submitted), (3) Notification
of Compliance Status, (4) Periodic Reports, and (5) other reports. The
requirements for each of the five types of reports are summarized
below.
a. Initial Notification. The Initial Notification is due 120 days
after the date of promulgation for existing sources. For new sources
that have an initial start-up more than 90 days after promulgation, the
application for approval of construction or reconstruction required
under the General Provisions must be submitted in lieu of the Initial
Notification. The application is due as soon as practicable before
commencement of construction or reconstruction, or 90 days after
promulgation of subpart G, whichever is later. For new sources that
have an initial start-up prior to 90 days after promulgation, no
application for approval of construction is required and the Initial
Notification is due within 90 days after promulgation.
The Initial Notification must list the chemical manufacturing
process units that are subject to subpart G, and which provisions may
apply (e.g., process vents, transfer operations, storage vessels, and/
or wastewater provisions). A detailed identification of emission points
is not necessary for the Initial Notification. However, the
notification must include a statement of whether the source expects
that it can achieve compliance by the specified compliance date.
b. Implementation Plan. The Implementation Plan details how the
source plans to comply with subpart G. An Implementation Plan is
required only for sources that have not yet submitted an operating
permit application.
Existing sources must submit the Implementation Plan at different
times for emission points included in averages and emission points not
included in averages. The Implementation Plan for emission points
included in an average is due 18 months prior to the date of
compliance. The Implementation Plan for emission points not included in
an emissions average is due 12 months prior to the date of compliance.
For new sources that have an initial start-up more than 90 days after
promulgation, the Implementation Plan must be submitted with the
application for approval of construction or reconstruction. For new
sources that have an initial start-up prior to 90 days after
promulgation, the Implementation Plan is due within 90 days after
promulgation (at the same time as the Initial Notification). This
timing for new source submittals is slightly different than in the
proposed rule.
The information in the Implementation Plan should be incorporated
into the source's operating permit application. The terms and
conditions of the plan, as approved by the permitting authority, would
then be incorporated into the operating permit.
For points included in an emissions average, the Implementation
Plan must include: An identification of all points in the planned
average and whether they are Group 1 or Group 2 points; the specific
control technique or pollution prevention measure that will be applied
to each point; the control efficiency for each control used in the
average; the projected credit or debit generated by each point; and the
overall expected credits and debits. The Implementation Plan must also
state that the same types of testing, monitoring, reporting, and
recordkeeping that are required by the proposed rules for Group 1
points will be done for all points (both Group 1 and Group 2) included
in an emissions average.
For emission points not included in an average, the Implementation
Plan must include a list of emission points subject to the process
vents, storage vessels, transfer operations, and wastewater provisions
and whether each point is Group 1 or Group 2. The control technology or
method of compliance planned for each Group 1 point must be specified.
The plan must also state that appropriate testing, monitoring,
reporting, and recordkeeping will be done for each Group 1 point.
If an owner or operator wishes to monitor a unique parameter or use
a unique recordkeeping and reporting system for any emission point in
their source, the request, including a rationale, must be submitted
with the Implementation Plan, unless this information has already been
included in their operating permit application.
c. Notification of Compliance Status. The Notification of
Compliance Status must be submitted within 150 days after the source's
compliance date. It contains information on Group 1 points and all
points in emissions averages that is necessary to demonstrate that
compliance has been achieved, such as: The results of any performance
tests for process vents, transfer operations, and wastewater emission
points; one complete test report for each test method used for a
particular kind of emission point; TRE determinations for process
vents; design analyses for storage vessels and wastewater emission
points; site-specific ranges for each monitored parameter for each
emission point and the rationale for the range; and values of all
parameters used to calculate emission credits and debits for emissions
averaging.
d. Periodic Reports. Generally, Periodic Reports must be submitted
semiannually. However, there are two exceptions. Quarterly reports must
be submitted for all points included in an emissions average. In
addition, if monitoring results show that the parameter values for an
emission point are outside the established range for more than the
number of excused excursions, the implementing agency may request that
the owner or operator submit quarterly reports for that emission point.
After 1 year, semiannual reporting can be resumed, unless the
implementing agency requests continuation of quarterly reports.
All Periodic Reports must include information required to be
reported under the recordkeeping and reporting provisions for each
emission point. For emission points involved in emissions averages, the
report must include the results of the calculations of credits and
debits for each month and for the quarter. For continuously monitored
parameters, the data on those daily periods when the parameters are
outside their established ranges are included in the reports. Periodic
Reports must also include results of any performance tests conducted
during the reporting period and reports of equipment failures, leaks,
or improper work practices that are discovered during required
inspections. Additional information the source is required to report
under its operating permit or Implementation Plan would also be
described in Periodic Reports.
e. Other Reports. Other reports must be submitted as required by
the provisions for each kind of point. Other reports include: reports
of start-up, shutdown, and malfunction; notifications of inspections
for storage vessels; and information about sources requesting approval
for a nominal control efficiency for use in calculating credits for an
emissions average.
C. Summary of Subpart H
The applicability and provisions of subpart H generally have not
changed since proposal. Minor changes have been made, however, to
clarify the EPA's intent in some provisions and some revisions were
made to recordkeeping and reporting provisions to reduce unproductive
efforts. The following is a brief summary of the requirements of the
provisions in subpart H of the final rule.
1. Applicability
The standards would apply to equipment in organic HAP service 300
or more hours per year that is associated with a process subject to
subpart F or I of part 63. The provisions apply to valves, pumps,
connectors, compressors, pressure relief devices, open-ended valves or
lines, sampling connection systems, instrumentation systems, surge
control vessels, bottoms receivers, and agitators. The provisions of
subpart H also apply to closed vent systems and control devices used to
control emissions from any of the listed equipment.
For SOCMI processes, compliance with the provisions of subpart H is
phased in by type of chemical manufacturing process. Subpart F divides
the regulated processes into five distinct groups to which the
provisions of subpart H apply beginning 6 months after publication of
the final rule in the Federal Register. Thereafter, subpart H applies
to another group of processes every 3 months. Table 1 of subpart F
lists the group to which each chemical manufacturing process subject to
this rule is assigned. Processes listed in subpart I must comply with
the provisions of subpart H 6 months after publication of the final
standard in the Federal Register.
a. Pumps and Valves. The standard requires leak detection and
repair for pumps in light liquid service and for valves in gas or light
liquid service. Standards for both are implemented in three phases. The
first and second phases for both types of equipment consist of an LDAR
program, with lower leak definitions in the second phase. The LDAR
program involves a periodic check for organic vapor leaks with a
portable instrument; if leaks are found, they must be repaired within a
certain period of time. In the third phase, the periodic monitoring (a
work practice standard) is combined with a performance requirement for
an allowable percent leaking components.
The standard requires monthly monitoring of pumps using an
instrument and weekly visual inspections for indications of leaks. In
the first two phases of the valve standard, quarterly monitoring is
required. In phase three, semiannual or annual monitoring may be used
by process units with less than 1 percent and less than 0.5 percent
leaking valves, respectively.
In phase three, if the base performance levels for a type of
equipment are not achieved, owners or operators must, in the case of
pumps, enter into a QIP, and in the case of valves may either enter
into a QIP or implement monthly LDAR. The QIP is a concept that enables
plants exceeding the base performance levels to eventually achieve the
desired levels without incurring penalty or being in a noncompliance
status. As long as the requirements of the QIP are met, the plant is in
compliance. The basic QIP consists of information gathering,
determining superior performing technologies, and replacing poorer
performers with the superior technologies until the base performance
levels are achieved.
b. Connectors. The rule also requires leak detection and repair of
connectors in gas or light liquid service. The monitoring frequency for
connectors is determined by the percent leaking connectors in the
process unit and the consistency of performance. Process units that
have 0.5 percent or greater leaking connectors are required to monitor
all connectors annually. Units that have less than 0.5 percent may
monitor biannually and units that show less than 0.5 percent for two
monitoring cycles may monitor once every 4 years.
c. Other Equipment. Standards for compressors, open-ended lines,
pressure relief devices, and sampling connection systems remain
essentially unchanged from the proposed standard and other existing
equipment regulations (See 40 CFR part 61, subpart V). The provisions
for closed vent systems were revised to make them consistent with the
provisions in subpart G, and to clarify intent. Agitators must be
monitored for leaks or better designed systems, such as dual mechanical
seals, must be installed. Pumps, valves, connectors, and agitators in
heavy liquid service; instrumentation systems; and pressure relief
devices in liquid service are subject to instrument monitoring only if
evidence of a potential leak is found through sight, sound, or smell.
Instrumentation systems consist of smaller pipes and tubing that carry
samples of process fluids to be analyzed to determine process operating
conditions or systems for measurement of process conditions.
2. Delay of Repair
Under certain conditions delay of repair beyond the required 15
days may be acceptable. Examples of these situations include where: (1)
A piece of equipment cannot be repaired without a process unit
shutdown, (2) equipment is taken out of organic HAP service, (3)
emissions from repair will exceed emissions from delay of repair until
the next shutdown, and (4) equipment with better leak performance such
as pumps with SMS are replaced with DMS.
3. Alternative Standards
Specific alternative standards have been written for batch
processes and enclosed buildings. For batch processes, the owner or
operator can choose either to meet similar standards to those for
continuous processes, with monitoring frequency prorated to time in use
of organic HAP, or to periodically pressure test the entire system. For
enclosed buildings, the owner or operator may forego monitoring if the
building is kept under a negative pressure and emissions are routed
through a closed vent system to an approved control device.
4. Test Methods and Procedures
The standards require the use of Method 21 of appendix A of part 60
to detect leaks. Method 21 requires a portable organic vapor analyzer
to monitor for leaks from equipment in use. Test procedures using
either a gas or a liquid for pressure testing the batch system are
specified to detect for leaks.
5. Recordkeeping and Reporting
The standards require certain records to demonstrate compliance
with the standard and the records must be retained in a readily
accessible recordkeeping system. Subpart H requires that records be
maintained of equipment that would be subject to the standards, testing
associated with batch processes, design specifications of closed vent
systems and control devices, test results from performance tests, and
information required by equipment in QIP. Other recordkeeping
requirements are specified in Sec. 63.181 of subpart H.
Subpart H requires owners and operators to submit three types of
reports: (1) An Initial Notification; (2) a Notification of Compliance
Status; and (3) Periodic Reports. Owners or operators subject to the
requirements of subpart G as well as subpart H may submit one Initial
Notification for both requirements. Owners or operators of sources
subject to subparts I and H must submit an Initial Notification that
lists the units subject to subpart H and the location of the source.
The Notification of Compliance Status must be submitted within 90 days
after the compliance date for process units in the first group.
Thereafter, the owner or operator must submit a Periodic Report every 6
months that contains summary information on the leak detection and
repair program, changes to the process unit, changes in monitoring
frequency or monitoring alternatives, and/or initiation of a QIP. The
Periodic Report will also include any Notification of Compliance Status
for any process units that had compliance dates in the previous 6-month
period. Reports can be submitted on electronic media that are
compatible with the system used by the Administrator or the State
permitting authority.
D. Summary of Subpart I
In contrast to the sources in the SOCMI source category, sources in
the non-SOCMI processes would be covered by subparts I and H only. For
these processes, the source would include only pumps, compressors,
agitators, pressure relief devices, sampling connection systems, open-
ended valves or lines, valves, connectors, and instrumentation systems.
As explained in the Source Category Schedule for Standards (58 FR
63941), the EPA is considering regulating the other kinds of emission
points in these processes in future section 112 standards. The
processes subject to subpart H of the HON are included in 20 different
source categories or subsets of source categories. The exact
relationship of the HON's equipment leak processes to the source
categories listed for section 112 standards is specified in table 1 of
the Source Category Schedule for Standards (58 FR 63941).
IV. Impacts
This section presents the environmental, energy, cost, and economic
impacts resulting from the control of HAP emissions under the rule. It
is estimated that approximately 370 sources and 940 chemical
manufacturing processes would be required to apply controls by the
standards.
Impacts are presented relative to a baseline set at the level of
control in the absence of the rule. The estimates include the impacts
of applying control to: (1) Existing emission points and (2) additional
emission points from SOCMI process units that are expected to begin
operation over a 5-year period. Thus, the estimates represent annual
impacts occurring in the fifth year. Assuming a SOCMI-wide growth rate
of 3.5 percent each year over a 5-year period, national impacts for the
emission points that will be added in the first 5 years of the rule are
estimated to be 19 percent of total national impacts in the fifth year.
A. Environmental Impacts
Environmental impacts include the reduction of HAP and VOC
emissions, increases in other air pollutants, and decreases in water
pollution and solid waste resulting from the proposed rule.
Under the rule, it is estimated that emissions of HAP would be
reduced by 460,000 Mg/yr (510,000 tons/yr) and the emissions of VOC's
would be reduced by 950,000 Mg/yr (1,000,000 tons/yr) (see table 1).
Estimates of baseline emissions are presented in conjunction with
emissions reductions estimates to better illustrate the level of
control being achieved by the rule. Baseline emissions take into
account the current estimated level of emissions control, based on
State and Federal regulations, for each SOCMI emission point. As a
result, baseline emissions reflect the level of control that would be
achieved in the absence of the rule.
The baseline emission estimates in table 1 include the
extrapolation of estimates for well-characterized processes to account
for processes that could not be characterized. Consequently, the table
1 estimates contain considerable uncertainty and are presented only to
provide an estimate of the total nationwide impact of the rule.
Decisions were based on information from the well-characterized
processes only. As discussed in section III.B.3 of this preamble, the
EPA has deferred the final decision regarding control of medium-sized
storage vessels at existing sources. Therefore, emission reductions for
storage vessels shown in table 1, and consequently the total, may be
slightly overstated.
On average, SOCMI sources generate over twice as much VOC emissions
as HAP emissions. Although the intent of the rule is to reduce HAP
emissions, the control of HAP's also results in the control of non-HAP
VOC's. The control requirements of the HON would result in reduction of
88 percent of HAP emissions and 79 percent of VOC emissions beyond the
baseline control level.
There would be a very slight increase in emissions of CO and
NOX, relative to other sources of these pollutants, resulting from
the on-site combustion of fossil fuels as part of control device
operations. Additional emissions of NOX and CO (and other
pollutants) resulting from increased electricity demand are not
included in the impacts presented. Under the rule, estimates of
increased emissions of CO and NOX are 1,700 Mg/yr (1,900 tons/yr)
and 17,000 Mg/yr (19,000 tons/yr), respectively (see table 2). The
impacts for process vents and transfer operations are based on the
assumptions that incinerators or flares are used to combust emission
streams. To the extent noncombustion controls are used to achieve
compliance with the standards, the actual CO and NOX emissions
would be lower.
Impacts for water pollution and solid waste were judged to be
negligible and were not quantified as part of the impacts analysis. The
basis for judging these impacts to be negligible is discussed in
chapter 5.0 of proposal BID volume 1A.
B. Energy Impacts
Increases in energy use were estimated for steam, natural gas, and
electricity. These three types of energy were compared and totaled on a
BOE basis. Table 3 shows the estimated individual and total energy use
increases. Estimates for total energy use are 290 million kw-hr/yr of
electricity, 6,900 billion Btu/yr of natural gas, and 3,000 billion
Btu/yr of steam. This equates to 13,000 TJ/yr (2.1 million BOE/yr).
C. Cost Impacts
Cost impacts include the capital costs of new control equipment,
the cost of energy (supplemental fuel, steam, and electricity) required
to operate control equipment, and operation and maintenance costs.
Generally, cost impacts also include cost savings generated by reducing
the loss of valuable product in the form of emissions. Average cost
effectiveness P($/Mg of pollutant removed) is also presented as part of
cost impacts. Average cost effectiveness is determined by dividing the
annual cost by the annual emission reduction.
For the final rule, it is estimated that total capital costs for
installation of controls would be $450 million (1989 dollars), and
total annual costs of this control, excluding the cost savings
attributable to equipment leaks, would be $160 million (1989 dollars)
per year (see table 4). Because of the EPA's deferral of a final
decision on control of medium-sized storage vessels at existing
sources, as discussed in section III.B.3 of this preamble, the cost
impacts for storage vessels, and consequently the total cost impacts,
may be slightly overstated. The estimated cost of the monitoring,
recordkeeping and reporting requirements for the rule is $70 million/
yr. The total nationwide annual cost of this rule is, therefore, $230
million/yr.
It is expected that the actual compliance cost of the rule would be
less than those presented, but it is not possible to quantify the
amount. This is because cost estimates for some kinds of emission
points were made assuming a separate control device would be
constructed for each emission point. In reality, some operators will
duct emissions from several of these emission points to a common
control device, upgrade an existing control device, use other less
expensive control technologies, implement pollution prevention
technologies, or use emissions averaging. Additionally, owners or
operators of sources may develop more efficient monitoring and
recordkeeping systems. All of these options would reduce the estimated
costs while achieving the same emission reductions. The effect of such
practices on the national costs could not be estimated because the
ability to use any of these practices is highly site-specific and data
were not available to estimate how often the lower cost compliance
practices could be utilized.
D. Economic Impacts
Because many SOCMI chemicals are used as raw materials in the
production of other SOCMI chemicals, the economic impact analysis
looked at cumulative costs of control for each of the SOCMI chemicals
listed in subparts F and H. About 94 percent of the chemicals are
estimated to have a production cost increase of less than 10 percent;
more than 88 percent have cost increases less than 3 percent.
Approximately 6 percent of the chemicals analyzed incur a cost increase
of over 10 percent. Almost all of the chemicals with a product cost
increase exceeding 10 percent have annual national production of less
than 10 million kilograms (11,000 tons) and are therefore low volume
chemicals. [Two-thirds of the SOCMI chemicals have production over 10
million kilograms (11,000 tons).]
Market analyses for a subset of 21 of the chemicals estimated price
increases from 0.1 percent to 3.9 percent and quantity decreases from
0.1 percent to 4 percent. The market analyses lead to the conclusion
that percentage quantity decreases will be less than the percentage
cost increases due to the regulation. The market analyses indicate that
severe disruption of the industry is an unlikely result.
The diversity of chemical producers (most sources are involved in
the production of several chemicals) decreases the likelihood of plant
closure as a result of the regulation. A more likely consequence of the
regulation is a change from a chemical manufacturing process with a
higher cumulative control cost to a process with a lower control cost.
The impact for the low volume chemicals is the most uncertain. The
cost estimates for these chemicals involve more uncertainty and, in
many cases, industry profile information specific to the manufacturers
of these chemicals was not available. Many of the low volume chemicals
can be considered specialty chemicals. Generally, there is a lack of
viable substitutes for specialty chemicals. In addition, the production
cost of specialty chemicals is usually only a small portion of the cost
of the final goods made with the specialty chemical. For these two
reasons, a price increase for a specialty chemical is less likely to
lead to a business closure or a production cutback than a price
increase for a large volume chemical. This decreases the likelihood of
large quantity impacts or closures.
The RIA addresses the benefits, costs, and economic impact of the
regulation. Because benefits could only be addressed qualitatively, the
RIA is not able to provide guidance as to which regulatory option
optimizes net benefits. However, the RIA does summarize the types of
benefits associated with the reduction of HAP's, VOC's, and particulate
matter formed from VOC's.
V. Summary of Significant Comments and Associated Changes to the
Proposed Subparts F and G
A. Selection of Source Category and Source
1. Definition of SOCMI
Public comments have indicated confusion regarding the definition
of the source category covered by the HON. Several commenters
misinterpreted the definition to include activities that were not
intended to be regulated with this rule such as marine vessel loading
and refinery processes. Thus, the commenters asserted that the proposed
rule contained too many exemptions and loopholes. The commenters
concluded that the EPA should broaden the scope of the HON.
Section 112(c) of the Act requires the EPA to publish a list of all
categories of major sources of listed HAP's (and such categories of
area sources as the Administrator determines warrant regulation), then
to establish rules for each of these categories of sources of HAP
emissions. As such, the HON was not intended to require controls for
all operations in the chemical industry. Rather, the HON sets section
112(d) standards for the SOCMI source category. The SOCMI source
category includes only the part of the chemical industry that produces
the major industrial chemicals. Other parts of the chemical industry
use SOCMI chemicals to produce pesticides, agricultural chemicals,
pharmaceuticals, polymers, and specialty chemicals. These operations
are substantially different than the SOCMI and were outside the scope
of the impact analysis for the HON. Accordingly, these other segments
of the chemical industry are separate source categories, and will be
subject to separate MACT or GACT standards at a later date.
The EPA acknowledges that some integrated facilities will have
operations from multiple source categories on the same plant site
(e.g., refinery units, SOCMI production, and pesticide production).
However, to include all emission points at these facilities in the
scope of the HON is inappropriate because it is not consistent with
Congressional intent to regulate categories of HAP emissions. Further,
such an undertaking would make implementation of the rule an
insurmountable task. Instead, the HON provides comprehensive coverage
of the emissions of 112 organic HAP's from five kinds of emission
points in 385 SOCMI production processes. Emissions from processes in
other source categories will be covered by separate MACT standards. In
conclusion, the EPA does not believe it would be practical or
appropriate to broaden the applicability of the HON, as suggested by
some commenters, to include emissions from other source categories.
In previous rules and in the proposed HON, the EPA defined the
SOCMI source category with lists of chemical products. In the proposed
HON, there were two lists of SOCMI chemicals. One listed chemicals that
would be subject to subpart G and the other listed chemicals that would
be subject to subpart H. The two differed because the subpart H list
had been agreed to by the negotiating committee before all technical
analyses were complete.
Commenters suggested simplifying the applicability of the HON by
making the lists identical or by combining them into a single list.
Other commenters asserted that there were non-SOCMI chemicals (e.g.,
phthalate esters) on the proposed lists and that these chemicals should
be removed from the final rule.
The EPA agrees with the commenters that the applicability of the
rule will be clearer if there is only one list of SOCMI chemicals.
Thus, the EPA has combined the two lists and placed the resulting list
in table 1 of subpart F of part 63.
The EPA re-evaluated several chemicals that some commenters had
claimed were not SOCMI chemicals. In several cases the EPA disagreed
with the commenters because the chemicals met the criteria that EPA has
used to define the SOCMI. However, the EPA agreed with the commenters
regarding phthalate esters. These chemicals are primarily used as
plasticizers, not as building blocks for other chemical manufacturing,
and will be regulated under a separate source category called
``Phthalate Plasticizer Production.'' Because the production of these
chemicals will be covered by a future section 112(d) standard, the EPA
felt that it would be inappropriate to include them under the HON.
Thus, phthalate esters were deleted from the list of SOCMI chemicals in
the final rule.
The EPA added a chemical to the HON SOCMI list that had previously
been listed as a separate source category. The dodecanedioic acid
process shares equipment with an adiponitrile process which is subject
to the provisions of the HON. The EPA determined that it would be more
appropriate to regulate production of dodecanedioic acid as part of the
HON rather than prepare a separate standard. Thus, this chemical has
been added to the list of SOCMI chemicals in the HON.
Several commenters have alleged that the applicability provisions
in the proposed HON are confusing, especially when applied to plant
sites with integrated operations. To address the confusion, the EPA has
clarified the provisions in the final rule to simplify the
determination of applicability for facilities with integrated
operations. Several commenters suggested that the term ``chemical
manufacturing process'' be clarified regarding where the coverage of
the HON begins and ends. The commenters described situations where:
(1) Unit operations produce a SOCMI chemical as part of an overall
non-SOCMI process;
(2) Solvent is recovered or reclaimed;
(3) Unit operations, storage vessels, and transfer racks are shared
by two or more processes; and
(4) The intended product is less than a by-product on a mass basis.
In the final rule, the EPA has changed the term ``chemical
manufacturing process'' to ``chemical manufacturing process unit'' and
provided additional clarification on the boundary of a process subject
to the HON. The term is now defined as follows:
Chemical manufacturing process unit means the equipment
assembled and connected by pipes or ducts to process raw materials
and to manufacture an intended product. For the purpose of this
subpart, chemical manufacturing process unit includes air oxidation
reactors and their associated product separators and recovery
devices; reactors and their associated product separators and
recovery devices; distillation units and their associated distillate
receivers and recovery devices; associated unit operations; and any
feed, intermediate and product storage vessels, product transfer
racks, and connected ducts and piping. A chemical manufacturing
process unit includes pumps, compressors, agitators, pressure relief
devices, sampling connection systems, open-ended valves or lines,
valves, connectors, instrumentation systems, and control devices or
systems. A chemical manufacturing process unit is identified by its
primary product.
Additionally, the final rule provides a comprehensive assignment
procedure for distillation units, storage vessels, and transfer racks
that are shared among processes. This assignment procedure is based on
the predominant use of the equipment. The EPA has also clarified the
term ``source'' by consolidating the definition into two adjacent
paragraphs and wording it more in terms of equipment having specific
functions. These and other clarifications should remove the confusion
on the limits of a chemical manufacturing process unit subject to the
HON.
Commenters also asserted that the proposed definition of ``flexible
operation unit'' was inadequate because it addressed only feedstock
changes, and not operating changes to accommodate different products or
specifications. Because changes in these units could be frequent, the
commenters suggested basing applicability on the previous year's
production.
In the final rule, the EPA has changed the definition of ``flexible
operation unit'' to include operating changes. Additionally, the EPA
reevaluated the proposed requirement that a flexible operation unit
would be subject to the HON only during times when the unit was
producing a SOCMI product. The EPA decided that, due to the frequent
product changes associated with flexible operation units, such a
provision could complicate compliance determinations for sources and
enforcement agencies. The EPA considered the commenters' suggestion to
base applicability on the previous year's production but decided
against this because the year preceding promulgation of the final rule
might not have been representative of typical operation of the unit.
Therefore, in the final rule flexible operation units are assigned to a
specific chemical manufacturing process unit based on the anticipated
use of the unit. For existing sources, assignment is based on the
expected use over the first five years following promulgation, and for
new sources, assignment is based on expected use in the first five
years after start-up.
2. Definition of Major Source
The EPA received a number of comments regarding a source's
potential to emit. The EPA's policy on potential to emit is enunciated
in the General Provisions. The reader is directed to those provisions
for guidance.
Public comments have indicated confusion on the applicability of
the HON to a SOCMI chemical manufacturing process unit at a plant site
where the predominant activity is part of another source category
(e.g., a petroleum refinery). Some commenters pointed out that the
permit rule (40 CFR 70.2) narrowed the basis for determination of major
source status to include only the emission points within a single two-
digit SIC code. The commenters argued that this change would mean that
the HON would apply only if a source was major due to its SOCMI
processes. In other words, if the SOCMI processes at a source did not
exceed the 10/25 tons per year HAP emission threshold, then the HON
would not apply.
The EPA maintains that, although 40 CFR 70.2 defines major source
for the purpose of permitting, it does not alter the statutory
definition under section 112. The permit rule applies to sources
subject to a section 112(d) standard regardless of whether they are
major sources as defined by 40 CFR 70.2.
The EPA's position remains that if a plant site is a major source
within the section 112 definition, the HON applies to the HAP-emitting
SOCMI processes, and that the applicability of the HON to the SOCMI
portion of the plant site is not limited by the principal activity at
the site. This is consistent with the intent of the Act to regulate
categories of HAP emission sources. The part 70 definition may result
in more than one permit being issued for a major source of HAP
emissions, but does not affect the applicability of MACT standards.
3. Exclusion of Area Sources
In the preamble to the proposed HON, the EPA requested information
on the existence and characteristics of any area sources in the SOCMI
in order to determine if a separate MACT standard should be prepared.
Because the comments did not indicate any reasons to develop an area
source standard, the EPA maintains that the HON applies to major
sources only. Area sources are not subject to the HON.
4. Determining New Source Status
The EPA received a number of comments regarding the process for
determining if new or existing source requirements would apply to a
particular SOCMI emission point or process unit. In response to those
comments the EPA has clarified the relevant section of subpart F. The
requirements and definitions used by the HON to distinguish new and
existing sources are consistent with section 112(a) and the related
components of the General Provisions. As a result, the following could
be subject to the HON's requirements for new sources: (1) Chemical
manufacturing process units constructed after the date of proposal of
the HON (December 31, 1992); (2) existing sources reconstructed after
that date; and (3) ``greenfield'' HON chemical manufacturing process
units that constitute all or part of a major source constructed after
that date. (New source requirements would not be triggered by the
addition of an individual emission point, such as a storage vessel.) In
addition, a newly constructed chemical manufacturing process unit must
also have the potential to emit major quantities (10 tons per year of
any HAP or 25 tons per year of any combination of HAP's) in order to be
subject to new source requirements for the HON. Thus, any change or
addition to an existing SOCMI plant site must meet the same three
criteria as a ``greenfield'' plant to be considered a new source. The
EPA selected this approach for determining what is subject to new
source requirements to avoid providing an incentive for SOCMI owners
and operators to construct processes as area sources. Also, EPA wanted
to ensure that new sources built at existing plant sites are subject to
the same requirements as new sources that are ``greenfield'' sites.
Additions to an existing plant that do not meet the requirements of
being a chemical manufacturing process unit and do not have the
potential to emit major amounts, will be subject to existing source
requirements.
B. Selection of Pollutants
In selecting the HAP's that would be regulated by the HON, the EPA
started with the list of 189 HAP's in the Act. Because the HON was
intended to reduce emissions from organic chemical manufacturing, the
EPA studied the processes used to manufacture SOCMI chemicals and
narrowed the list to those organic HAP's that would be emitted from
SOCMI processes.
In the proposed rule, there were two lists of organic HAP's--one
that applied to subpart G and another that applied to subpart H. The
lists differed by 37 HAP's because the subpart H list had been agreed
to by the negotiating committee before all technical analyses were
complete. These technical analyses indicated that 37 of the organic
HAP's on the list approved by the committee should be removed from the
list because they would not be emitted from SOCMI production processes.
In public comments received on the proposed rule, it was suggested that
the EPA combine the two lists to simplify implementation of the rule.
The EPA decided that it was appropriate to include only one list of
organic HAP's in the final rule. The list is located in table 2 of
subpart F and contains 112 compounds. Keeping the shorter of the two
proposed lists will not result in greater emissions because the
additional 37 HAP's on the longer list would not be emitted from SOCMI
processes. Also, because the non-SOCMI processes in subpart I are only
subject to the standard for the designated pollutants, combining the
organic HAP lists does not affect emissions from those processes.
C. Selection of Rule
1. Floor Determination
a. Background on impacts estimates. As explained in the preamble to
the proposed rule (57 FR 62621), the EPA developed the information on
control costs and emissions for SOCMI using a model emission point
approach to represent the broad range of characteristics of SOCMI
operations. The EPA elected to use the model emission point approach in
part because of the limited time provided by the statutory requirement
to regulate 40 source categories (which legislative history states
should be the priority elements of the chemical industry) by 1992 and
to establish regulations for all initially listed source categories by
2000. Because a generic model emission point approach allows one
regulation to cover a large number of different chemical processes, it
was considered more resource efficient and the only practical way to
develop regulations on the schedule mandated by Congress.
The impacts estimation methodology involved three steps: (1)
Development of a data base characterizing the SOCMI, (2) development
and assignment of model emission points for each kind of emission
point, and (3) calculation of emissions and control impacts. The
characterization of the SOCMI primarily involved identifying the
specific routes, reactants, and process technologies used to produce a
chemical and the corresponding SOCMI chemical manufacturing process
units. In addition, information on existing State and Federal
regulations was compiled for each kind of emission point to determine
the baseline control requirements applicable to SOCMI chemical
manufacturing process units.
Model emission points were developed to represent each kind of
emission point in the SOCMI. The models were developed to emphasize
those characteristics that most influence emissions, control costs,
energy needs, and secondary environmental impacts. These models were
applied to individual chemical manufacturing process units in the SOCMI
data base using decision rules based on the level of information in the
data base and the specificity of a given model. These models are
representative of average, representative, or typical emissions for the
specific process or reaction type. Thus, the estimates do not reflect
actual emissions that would occur at any particular chemical
manufacturing process unit because process design and operation
characteristics vary from plant to plant.
Estimates of existing controls were developed by compiling
information in existing state and Federal regulations applicable to
SOCMI processes. In this analysis, the EPA used data on the control
requirements in existing State and Federal regulations to identify
those emission points that must be controlled in the absence of this
rule and to identify the required controls. It was assumed that all
chemical manufacturing process units would be in compliance with
applicable air pollution regulations.
The data base and model emission points used to estimate the
impacts of the HON are based on published literature and information
that the EPA has collected during other rulemaking efforts including
NSPS for air oxidation processes, distillation operations, reactor
processes, volatile organic liquid storage, and equipment leaks; and
NESHAP for vinyl chloride and benzene. Some additional information was
obtained on wastewater operations and transfer loading operations by
requesting it from the industry under authority of section 114 of the
Act.
In development of the proposed rule, the EPA recognized that the
data base developed to provide estimates of nationwide costs and
emission reductions did not provide site-specific emission and control
information and these limitations needed to be considered in the
determination of the floor for the category. The EPA developed the
floor from an analysis of the information for each kind of emission
point. The information the EPA used in determining the source-wide
floor consisted of the estimates of the number and characteristics of
the model emission points, the emission control requirements currently
in place for each point based on information available to the EPA, and
the expected control efficiencies for the control technology. To
determine the source-wide floor for existing sources at proposal, the
EPA examined the supporting information to identify the emission
characteristics of the emission points which had at least 12 percent of
the points controlled by the reference control technology. This
analysis was done for each kind of emission point. The characteristics
used to identify groups of emission points were physical parameters
such as flow rate, HAP concentration, and vapor pressure. The source-
wide floor was determined by the combination of the control levels for
all four kinds of emission points.
A similar method was used to determine the source-wide floor for
new sources. For each kind of emission point, the characteristics of
the smallest emission point controlled by the reference control
technology were identified as the means for determining the best
controlled similar source. Again, the source-wide floor was determined
by the combination of control levels for all emission points.
b. Public comment issues. Commenters raised three basic issues on
the approach used to determine the floor for SOCMI sources:
(1) Information used to predict existing control understated actual
control present;
(2) The methodology used to estimate the floor overstated the
floor; and
(3) The ranking criterion used for process vents introduced cost
considerations into the floor.
Data base understates actual control. A number of commenters argued
that the approach, or the information, the EPA used understated actual
control in the SOCMI. Some of these commenters thought that the EPA
should have gathered site-specific data on emissions and controls to
properly establish the floors. Other commenters argued that the EPA
should have used state air toxics and new source review permits to
determine actual control levels, since many air toxics programs are
implemented through permit programs.
While the EPA would have preferred to have developed site-specific
information on emissions and controls for processes subject to this
rule, it was not possible to do so given the deadlines applicable to
this rulemaking. Section 112(e)(1) of the CAA required that the EPA
promulgate emission standards for at least 40 source categories and
subcategories by November 15, 1992. Having failed to meet that
statutory deadline, the EPA entered into a consent decree requiring the
promulgation of the HON by February 28, 1994. Neither that deadline nor
the statutory deadline for the rules covering 40 source categories and
subcategories could have been met if the EPA used the alternative
approach suggested by the commenters. The EPA's past experience in
developing the data base for the previous section 112 program and for
NSPS standards demonstrates the great length of time necessary to
develop and analyze the data for development of emission standards to
control emissions from the SOCMI. The data base developed for this
rulemaking used the results of more than 10 years of data gathering and
analysis of SOCMI sources. Developing an entirely new data base as
suggested by the commenters is expected to require anywhere from 4 to
10 years depending on the degree of evaluation of performance and
whether permits are reviewed for all SOCMI sources. Consequently, the
EPA elected to use information readily available to it to determine the
floor for the SOCMI standard under section 112(d) of the CAA. In light
of the EPA's prior experience with regulation of the SOCMI, the EPA
believes that this decision was entirely reasonable.
Furthermore, the EPA does not believe that the method used by the
EPA to determine existing control levels and the floor understated
actual control levels in SOCMI. The EPA holds this view because other
assumptions used in the analysis introduced a positive bias. Examples
of assumptions that would introduce an upward bias to the analysis
include: (1) All sources are in compliance with all applicable control
requirements for air emissions; and (2) sources would be in compliance
with recently established requirements such as 40 CFR part 61 subpart
BB. Thus, the EPA believes that taken as a whole the uncertainties
should balance out, and the control level is not understated. It should
be noted also that other commenters thought that the floor was
overstated.
Methodology overstated floor. In contrast, another group of
commenters argued that the point-by-point approximation of the floor
introduced a positive bias in the source-wide floor. These commenters
explained that the assumption that the best controlled of each kind of
point are co-located is invalid. They noted that in practice different
sources have the better controls on the different kinds of points.
These commenters argued that the EPA should have considered this bias
in decisions to require control beyond the floor. Some of these
commenters also questioned inclusion of requirements in recent NESHAP
in the assessment of the floor control and the estimates of control
efficiency achieved by some control devices. None of the commenters
provided data or suggested methodologies that could be used to improve
the EPA data base to develop better estimates of the source-wide floor.
The EPA maintains that, given the uncertainties in the data base,
the procedure used to determine the floors in the proposal (and in this
final rule) is a reasonable approach to the determination of the floor.
As explained above, the EPA could not develop actual site-specific data
in the time available for this rulemaking. Thus, the EPA had to rely on
existing data sources to develop model emission points characteristics
for sources subject to this rule. Where data were available for the
specific process, the model emission points characteristics reflected
average or representative operations for the specific process. In cases
where no data were available for a specific process, the model emission
point characteristics were derived from average characteristics for the
generic reaction type (e.g., hydrogenation, halogenation, etc.). Thus,
the estimates cannot be viewed as reflecting actual emissions and
controls at any particular process unit or plant site. The EPA
considered whether to develop floors using estimates of site-specific
emissions and controls and rejected that approach as introducing
additional assumptions and such large uncertainties as to render the
analysis meaningless. For example, due to incomplete information, it is
probable that not all process units at each plant site were properly
identified. In fact, locations of some chemical production processes
are unknown. Site specific differences in process unit design could not
be taken into account in assigning model emission points and baseline
control levels. Thus, there is uncertainty about the existence of any
particular emission point, as well as its assigned emission and control
level at any particular plant site. Furthermore, independent assignment
procedures were used for each kind of emission point. In consideration
of these factors, the EPA believes that the uncertainties introduced by
the assumptions made in assigning emission point characteristics to
specific sites are so large as to undermine the validity of the
analysis. The EPA believes that the approach it used of developing
point-by-point approximations of the source-wide floor was the most
appropriate use of the available data base to determine the floors.
Moreover, the EPA does not believe that its methodology, when all
aspects are considered, did overstate the source-wide floor. While the
assumption of collocation of the best controlled points does introduce
an upward bias in the analysis, there are other aspects of the analysis
that work in the opposite direction. For example, the use of
information from State regulations instead of site-specific control and
operation information would be likely to understate the degree of
control present in some sources. As previous commenters noted, site-
specific controls that may have been included in new source permits or
applied voluntarily could not be accounted for in the data base. Thus,
the EPA expects these factors are likely to balance out. It should be
noted also that other commenters thought that the floor was
understated.
The EPA also believes that its choice of methodology was reasonable
since it provided additional assurance that, not withstanding the
uncertainties inherent in the data base, the floor determined by the
EPA would be no less stringent than the actual source-wide floor. As
some of the uncertainties present, such as the reliance on analyses of
State regulations rather than actual permitted levels of emissions,
would lead to a less stringent floor in the absence of countervailing
factors, the EPA believes it was reasonable to provide a safety factor
by determining the floor on the basis of a point-by-point approximation
that assumed the co-location of the best-controlled points.
In any event, even if the EPA's point-by-point methodology may have
overstated the floor, such an overstatement does not invalidate the
emission standard since the overall source-wide standard exceeds the
floor determined by the EPA.
A second issue raised regarding the methodology and information was
whether it was appropriate to consider the Benzene Transfer (40 CFR
part 61, subpart BB) or Benzene Waste (40 CFR part 61, subpart FF)
NESHAP as applicable control requirements. These commenters questioned
whether section 112(d)(3)(A) of the Act required that these control
requirements not be considered in the floor determination. (See section
II.C of this notice.)
The EPA maintains that it was appropriate to consider the control
requirements of Benzene Transfer since these controls were required
more than 30 months before promulgation of this rule. Furthermore,
information collected in the section 114 surveys shows that a few
sources were steam stripping wastewater containing chemicals with
volatilities similar to benzene. Because the new source floor is
determined based on the best controlled similar source, the
requirements were included in the determination of the floor for new
sources. In addition, the Vinyl Chloride NESHAP, which was issued in
1977, also requires treatment of wastewater streams containing greater
than 10 ppm. Consideration of the Benzene Waste NESHAP did not affect
the existing source floor because fewer than 1 percent of the
wastewater streams in the HON data base are expected to be subject to
Benzene Waste NESHAP control requirements, and the floor is determined
to be no control for wastewater streams at existing sources.
Ranking criterion used for process vents analysis. Some commenters
thought that the EPA had introduced cost considerations into the floor
by the ranking procedure used for process vents. These commenters noted
that considering cost in determining the floor was contrary to
Congressional intent.
The EPA does not believe that the procedure used to rank process
vents did introduce cost into the determination of characteristics of
process vents controlled at the floor. The reasons EPA holds this view
can be best explained by restating the process used and comparing it to
other ways of analyzing the process vent data.
To determine the source-wide floor, the EPA ranked the data base
for the specific emission point by a characteristic that would affect
the likelihood for control. For existing sources, the proposed floor
was defined as the emission characteristics where at least 12 percent
of the points were controlled by the reference control technology. For
new sources, the proposed floor was defined by the characteristics of
the point with the smallest emission rate that was controlled. By
analyzing the ranked data, it could be determined that emission points
with certain physical characteristics are currently controlled, while
emission points with other characteristics are not controlled. Storage
vessels, for example, were ranked by vapor pressure because vapor
pressure is one of the three major factors that influence emissions and
potential emission reductions. The ranking clearly showed that vessels
storing liquids above a certain vapor pressure are controlled at the
best controlled sources, so the source-wide floor would require control
of such vessels; whereas, vessels storing liquids with lower vapor
pressures are not currently controlled and would not require control
under the source-wide floor.
Process vents were ranked using cost effectiveness of control (or
TRE) as a surrogate measure because this can be used to reflect all
possible combinations of various factors that affect emission rates and
likelihood of current control (flow rate, HAP concentration, net
heating value, and corrosion properties). Use of a single criterion of
cost effectiveness results in a more easily understood parameter and is
consistent with the format of the process vent provisions. The cost-
effectiveness values were used only to rank the vents in the data base
and as a characteristic to identify controlled vent characteristics
(similar to the way in which vapor pressure was used to identify the
characteristics of the best controlled storage vessels). In determining
the process vent component of the source-wide floor, no judgements were
made about the reasonableness of the characteristics of the controlled
vents.
Because of the opinions expressed by commenters, the EPA also
reevaluated the process vent control level associated with the floor
using emissions as the ranking parameter. Emissions correlate with
likelihood of control, but the correlation is weaker because other
factors (such as concentration and flow) also influence it. The process
vent data base was ranked by vent from lowest to highest emission rate.
The characteristics of the process vent where at least 12 percent of
the process vents are controlled is 64 Mg/yr (71 tons/yr) and the cost-
effectiveness value is $1,620/Mg ($1,460/ton). Thus, essentially
identical results are obtained by both ranking procedures.
As discussed in section V.C.1.c of this preamble, comment has been
requested in other rulemakings on the meaning of the statutory language
``the average emission limitation achieved by the best performing 12
percent of the existing sources.'' Because of this, the average
characteristics of the top 12 percent of the process vents were
determined using the emissions ranking of the data base. This analysis
showed that vents with 27 Mg/yr (30 tons/yr) emissions would have to be
controlled at the floor. When these average characteristics are used to
derive the comparable TRE value, the result is about $2,900/Mg ($2,600/
ton). The discussion of the control levels selected for existing
process vents demonstrates that in this case the interpretation of the
statutory floor language is not relevant. This is the case because,
when cost and environmental and energy impacts are considered, as
required by the statute, the appropriate control level for process
vents is equal to the more stringent floor calculation. Thus any
ambiguity in the floor language and methodology does not affect the
regulatory alternative selected for this rule.
Analysis of expected control efficiency at floor for storage
vessels at existing sources. Several commenters questioned the
assessment of the performance capabilities of actual controls on
existing storage vessels. As discussed in section V.C.3 of this
preamble, the performance was reassessed considering the comments. This
reevaluation determined that for existing storage vessels best control
systems are:
(1) A 90-percent efficient control device; or
(2) An IFR or EFR with a continuous seal, but without controlled
fittings.
Also in the reexamination of existing control level, it was
determined that an error had been made in assignment of applicability
of the Benzene Storage NESHAP (40 CFR part 60, subpart Y) to storage
vessels in the data base. Upon examination of the data base, it was
found that some vessels had been assumed to be controlled due to
subpart Y, but the liquids stored did not meet the applicability
criteria of subpart Y. The Benzene Storage NESHAP applies only to
vessels storing liquids that meet the specifications of ASTM D-836-84
for industrial grade benzene, or refined benzene -485, -535, or -545.
After correction of the data base, 2 percent of the small vessels, 6
percent of the medium vessels, and 12 percent of the large vessels were
found to be controlled. The effect of this on the assessment of the
floor for existing sources is discussed in the next section of this
preamble.
c. Interpretation of statutory language for existing source floors.
In recent Federal Register notices of proposed rulemakings (Pulp and
Paper and Chromium Electroplating), the EPA has requested comment on
the EPA's interpretation of the meaning of ``the average emission
limitation achieved by the best performing 12 percent of the existing
sources'' and the methodology for determining the MACT floor. Comments
have been specifically requested in these proposed rulemakings on
whether the MACT floor for existing sources should be set at the 88th
percentile or at the level reflecting the median or mean level of
control achieved by the best performing 12 percent of sources.
Questions have been raised on how the methodology used in determination
of the floors for the HON relates to floors being determined using
alternative procedures.
With the exception of process vents and medium-sized storage
vessels, the two methodologies result in the same control level for the
floor. This results because for most of the HON data base there is
little variation in the physical characteristics of the emission points
in the top 12 percent of the population. The average or mean is equal
to the median value of the distribution as well as the 88th percentile
value. Thus, for this data base, whether the floor is determined using
the characteristics of the median, mean or 88th percentile does not
matter. The assessment of the average characteristics of the best
performing 12 percent of each kind of point is described below.
As described earlier in the discussion of the process vent ranking
criterion, the average characteristics of the top 12 percent of the
process vents was equivalent to about $3,000/Mg ($2,700/ton). The
characteristics of process vents where at least 12 percent are
controlled by the reference control technology is equivalent to $1,500/
Mg ($1,360/ton).
For small storage vessels, the revised data base showed that only 2
percent of the vessels were controlled. Thus, the median
characteristics of the top 12 percent of the vessels is no control.
This control level is the same as the level predicted by
characteristics where at least 12 percent are controlled.
As mentioned earlier, the EPA is not taking final action at this
time concerning the provisions applicable to medium storage vessels.
The reason is to take comments on the difference in the floor
determination that would result from the application of the two
interpretations discussed above. For medium storage vessels, 6 percent
of the vessels are controlled with either a 90-percent efficient
control device or an IFR or EFR with a continuous seal. All of the
controlled medium-sized vessels contained liquids with vapor pressures
of 13.1 kPa (1.9 psia). The arithmetic average, or mean characteristics
of the top 12 percent of the medium vessels would not represent the
performance of any known technology. If the EPA used the median as the
average for these vessels, however, the floor determined by the average
characteristics of the top 12 percent of the sources would require
control of vessels storing liquids with vapor pressures of 13.1 kPa
(1.9 psia) by either a 90-percent efficient control device or an IFR or
EFR with a continuous seal. This is the same vapor pressure that was
identified at proposal. With the revised data base, the floor
determined by the characteristics where at least 12 percent of the
points are controlled would require no control.
For large storage vessels, the revised data base showed that 12
percent of the vessels were controlled and essentially all controlled
vessels in the top 12 percentile of each size range of vessels stored
liquids with vapor pressures of 13.1 kPa (1.9 psia). So the median or
average characteristics of the top 12 percent of the vessels is the
same as the characteristics where at least 12 percent of the vessels
were controlled. Both procedures show the floor to require control of
vessels containing liquids with vapor pressures of 13.1 kPa (1.9 psia)
and higher.
The data base information for transfer racks also showed that all
controlled racks loaded liquids with vapor pressures of 10.3 kPa (1.5
psia) and no racks loading liquids with vapor pressures less than 10.3
kPa (1.5 psia) were controlled. Thus, the two procedures would predict
the same control requirements for the floor.
Fewer than 1 percent of the wastewater streams in the HON data base
were expected to be subject to regulations that required control of air
emissions. Thus, for wastewater the average of the top 12 percent of
streams would represent no control since the median stream is not
controlled and the arithmetic average of the top 12 percent of the
sources does not correspond to any known control measure. The
alternative procedure for determining the floor also shows that the
floor would be no control.
In summary, the outcome of the debate concerning the appropriate
interpretation of the floor language is not pertinent to the final
provisions for process vents, transfer operations, wastewater, small
storage vessels, and large storage vessels. Under either
interpretation, the floor would not alter the regulatory decisions
contained in this rule for those emission points because the standard
is, on the basis of cost and environmental and economic impacts, set at
or above each component of the floor regardless of which interpretation
is chosen. In the case of medium storage vessels, however, the EPA is
deferring final action pending the receipt and review of additional
public comment.
2. Alternative Control Levels
a. Stringency of standard. The proposed standard would have
required control of emission points with characteristics meeting the
criteria listed in table 5 through the use of reference control
technologies. The EPA selected the proposed control requirements from
the alternatives listed in tables 5 and 6 of the proposed notice of
rulemaking (57 FR 62629 and 62630). These alternatives differed only in
the number of emission points that would be controlled by the reference
control technology. The proposed requirements were selected
considering: (1) Magnitude of the emission reduction; (2) cost of the
emission reduction; (3) economic impacts and feasibility; (4)
consistency with previous decisions; (5) other non-air quality health
and environmental impacts; and (6) energy requirements. It was the
EPA's judgement that the proposed requirements would be achievable at
reasonable cost, and with reasonable economic and other impacts.
The proposed control requirements were expected to significantly
reduce HAP emissions from SOCMI sources. The proposed standard was
estimated to reduce HAP emissions from the four kinds of emission
points by 422,000 Mg/yr (464,000 tons/yr) from existing and new
sources. At proposal the total nationwide annual cost associated with
this emission reduction was estimated to be about $182 million/yr, with
$48 million/yr of this cost associated with the monitoring,
recordkeeping, and reporting requirements.
Public comments on the proposed control levels were polarized with
industry groups arguing the proposed standard was too stringent and
environmental and public interest groups arguing the standard did not
require sufficient control. Commenters who argued that the standard was
too stringent thought that in the decisions to go beyond the floor the
EPA should have considered the bias introduced by the procedure used to
determine the floor. Several commenters suggested alternative criteria
which they considered to be more appropriate. These commenters,
however, did not provide supporting rationale for their preferences.
Commenters representing environmental and public interest groups
expressed concern that the proposed standard did not require control of
all emissions, but allowed a large amount of emissions to go
uncontrolled. Several State and local regulatory agency commenters
thought that, at a minimum, the standard should have required control
comparable to existing control requirements for VOC, such as the NSPS
standards for SOCMI process vents (40 CFR part 60, subparts III, NNN,
and RRR).
The EPA considered all of the comments in selecting the final
control requirements of the standard. In considering these comments,
the EPA viewed the concerns in the context that the positions and
concerns were diametrically opposed to one another. Thus, no response
could completely resolve the issues. The EPA's reexamination of the
control requirements of the standard and response to the commenters'
concerns is provided in the following paragraphs of this section of the
preamble.
The final regulatory alternatives for existing and new sources are
shown in tables 6 and 7.
[Note: Regulatory alternatives were developed using information
for the chemical processes that could be characterized sufficiently
to permit assignment of model emission points. The estimates
presented in tables 6 and 7 differ from the estimates summarized in
section IV of this notice because the estimates in section IV
include an extrapolation to account for processes that could not be
modeled.]
The only differences between these alternatives and the
alternatives at proposal are revisions made to the estimates of
wastewater emissions and control costs and the storage vessel control
costs, as discussed in sections V.C.3.b and V.C.3.d of this preamble.
The following discussion of the final selection of control levels
is limited to the primary factors that affected the decision. The
primary factors are the emission reduction, control cost, consistency
with other standards, and economic efficiency. Other factors such as
non-air environmental impacts (solid waste and water) and energy
impacts do not vary significantly among the alternatives. Consequently,
these factors are not discussed in this preamble. Readers should see
the proposed rulemaking (57 FR 62608) for the discussion of these other
factors.
(i) Process vents. In the final rule, the EPA selected Option 3
(TRE cost-effectiveness values of up to $3,000/Mg) as the basis for the
requirements for process vents at existing sources. The EPA's selection
of Option 3 for process vents was principally based on consideration of
the emission reductions, costs, and consistency with other standards.
Specifically, the control level required by this option will reduce
emissions by 2,000 Mg/yr (2,200 tons/yr) more than Option 2, upon which
the proposed requirements were based. This additional emission
reduction is estimated to cost approximately $4 million/yr more than
Option 2 or $2,500 for each additional Mg of emissions ($2,270/ton).
The EPA believes that the control required by Option 3 is
achievable considering the statutory criteria, for the following
reasons. First, EPA has received extensive comment on the proposed
rule. No commenters submitted data or arguments demonstrating that the
costs of the proposed range of options (Options 1 to 4) were
unreasonable. Second, the incremental cost effectiveness of Option 3
compared to Option 2 ($2,500/Mg [$2,275/ton]) is within the cost-
effectiveness values from recent decisions on other standards. Third,
the TRE format of the process vents provisions allows facilities the
flexibility to comply through changes in equipment or operations. As a
result, actual costs could be lower than estimated. Based on the above
considerations, the EPA judged that the control required by Option 3 is
achievable considering the statutory criteria.
Fourth, Option 3 would provide consistency between the HON and the
recently issued CTG for SOCMI process vents, which requires control of
vents with TRE cost-effectiveness values of $2,500/Mg of VOC ($2,270/
ton). Option 3 would also be consistent with the applicability criteria
for the three SOCMI process vents NSPS, which require control of vents
with TRE cost-effectiveness values of $3,000/Mg of VOC ($2,700/ton)
adjusted to 1989 dollars. The EPA believes that consistency among these
requirements would reduce administrative costs and implementation
difficulties for both EPA and permit authorities as well as industry.
An additional consideration in selection of Option 3 was public
comments that the requirements should be at least equivalent to the
requirements of the SOCMI NSPS and CTG.
In addition, Option 3 is consistent with one interpretation of the
statutory language on floors, and thereby arguably is the minimum
statutorily permissible level of control. However, based on the above
analysis, Option 3 would have been selected whether it was equal to or
above the floor.
More stringent control than Option 3 was not selected because the
EPA could not conclude, based on currently available information, that
the additional emission reduction warranted the additional cost in this
case. The control level for Option 4 as compared with Option 3 would
achieve an additional emission reduction of 1,100 Mg/yr (1,200 tons) at
an additional cost of $4 million/yr. The incremental cost effectiveness
of Option 4 relative to Option 3 is $3,900/Mg ($3,500/ton).
The final standard retains the proposed requirement for control of
process vents with TRE cost-effectiveness values of $11,000/Mg ($9,980/
ton) at new sources. The EPA considered selecting a level of emission
reduction more stringent than the level associated with the source-wide
floor for process vents at new sources. However, a standard more
stringent than the floor component is not being established because the
costs were considered high given the very small additional emission
reduction available. The additional control would achieve an additional
emission reduction of about 100 Mg/yr at a cost of about $4 million/yr,
or $47,000 for each additional Mg of emission reduction ($43,000/ton).
Therefore, the control level associated with the source-wide floor was
considered to represent the maximum reduction achievable for new
sources considering cost and other impacts. The final standard for new
sources reflects the floor level of control for process vents.
(ii) Storage vessels. As described in section V.C.3.b of this
preamble, the cost analysis for storage vessels at existing sources was
revised after consideration of public comments on the assumptions in
the cost analysis. These revisions are reflected in the control cost
estimates in table 6. The EPA also revised its estimate of control
levels achieved by storage vessels at existing sources. As discussed in
section V.C.1 of this preamble, the best controls are IFR or EFR seals
without controlled fittings or a 90 percent efficient control device.
Because these controls are less economically efficient than the
proposed option, which was based on the existing requirements in 40 CFR
part 60 subpart Kb, the EPA did not develop a regulatory alternative
corresponding to floor control levels for all storage vessels at
existing sources. Instead, the regulatory alternatives in table 6
reflect the combination of: (1) The proposed control requirements for
vessels, which at the time of proposal were equipped with less
efficient controls than the control at the revised floor and (2) the
floor control for vessels, which at the time of proposal were equipped
with the floor controls. The alternatives were structured in this
manner because the EPA could not conclude, based on currently available
information, that requiring replacement of existing well- operated and
maintained controls that met the control efficiency achieved by sources
at the floor was justified. This additional control was estimated to
cost about $38,000 for each additional Mg of emission reduction
achieved ($34,000/ton).
For small storage vessels at existing sources, the maximum
potential reduction of 380 Mg/yr would cost about $22 million/yr, or
$58,000 for each additional Mg ($52,000/ton). Due to the relatively
high incremental costs and low emission reductions of these
alternatives, the EPA believes that the control level for the small
storage vessels component of the source-wide floor for existing sources
represented the maximum reduction achievable considering cost and other
impacts.
As discussed in section III.B.3 of this preamble, the EPA is not
taking final action at this time regarding medium vessels at existing
sources.
For large storage vessels at existing sources, the EPA considered
but rejected changing the control levels from the proposed
requirements. The selected control level achieves an additional 3,100
Mg/yr (3,400 tons/yr) emission reduction above Option 1 at an
additional cost of $5 million/yr, or about $1,600 for each additional
Mg ($1,400/ton). Another consideration was that the selected control
requirements are consistent with the requirements in the NSPS for
storage vessels (40 CFR part 60, subpart Kb).
The more stringent control option, Option 3, was not selected
because although it would achieve roughly an additional 4,000 Mg/yr
(4,400 tons/yr) emission reduction, the additional cost would be
substantial ($15 million/yr). This would be equivalent to about $4,000
for each additional Mg of emission reduction ($3,600/ton). The EPA
could not conclude, based on currently available information, that the
additional emission reduction warranted the additional cost in this
case.
The control decisions for storage vessels at new sources were also
reexamined. The regulatory alternatives in table 7 reflect minor
revisions made to the cost analysis as a result of public comments.
After considering the alternatives and the associated impacts, the EPA
concluded that the proposed requirements represented the maximum
reduction achievable considering costs and other impacts. More
stringent control than the proposed levels would not reduce HAP
emissions significantly enough to warrant the increase in control
costs.
For small and medium vessels at new sources, none of the
alternative control options more stringent than the floor components
were selected. After considering the emission reductions, costs, and
other impacts of the alternatives, the EPA determined the cost to
achieve the additional reduction was high given the very small
potential emission reductions. Additional control would reduce
emissions from medium storage vessels by less than 20 Mg/yr (22 tons/
yr) at an additional cost of about $750,000/yr, or $47,000 for each
additional Mg. For the small storage vessels segment of the population,
further control would result in less than 10 Mg/yr (11 tons/yr)
emission reduction at an added cost of about $2.3 million/yr or
$336,000 for each additional Mg. Therefore, due to the relatively high
incremental costs and low incremental emission reductions, the EPA
determined that the control level for the small and medium storage
vessels components of the source-wide floor for new sources represented
the maximum reduction achievable considering cost and other impacts.
For large storage vessels at new sources, the EPA concluded that
the proposed control levels represented the maximum reduction
achievable considering costs and other impacts. The control requirement
for large storage vessels is estimated to achieve an emission reduction
of 1,700 Mg/yr (1,900 tons/yr) of HAP's compared to emissions that
would occur without the standard. This represents an 84 percent
reduction from this segment of the SOCMI storage vessel population. The
annual cost to achieve this reduction is about $2.9 million and the
average cost effectiveness of this control is $1,700/Mg ($1,500/ton).
More stringent control was not selected because the additional emission
reduction of 3 Mg/yr achieved through further control is not
significant, given the additional cost ($300,000/yr). This cost was
judged to be disproportionately high.
(iii) Transfer operations. No changes were made to the estimates of
emissions or control costs for transfer operations. The final transfer
operations control requirements for both existing and new sources are
unchanged from the proposed requirements. More stringent control was
not selected because the small additional emission reduction that could
be achieved was disproportionate to the cost. The incremental cost
effectiveness of the additional emission reduction that could be
achieved is $54,000/Mg.
(iv) Process wastewater. As discussed in the proposed notice of
rulemaking (57 FR 62643-62645), there were a number of issues regarding
the emission and control cost estimates that the EPA was evaluating at
the time of proposal. The EPA has completed its evaluation of these
issues, and section V.G.4 of this preamble summarizes the basis for the
final estimates for SOCMI sources subject to the HON. A more detailed
description of the analysis and basis for the final estimates is
provided in the BID and docket A-90-23. The emission and control cost
estimates provided in tables 6 and 7 reflect the revised emission and
cost estimates for process wastewater. The revised estimates are
approximately 20 percent lower than the estimates presented at proposal
(57 FR 62629-62630).
The EPA reexamined the proposed control requirements in light of
these changes and public comments on the stringency of the standard.
After considering the alternatives and the associated impacts, the EPA
concluded that the proposed control criteria for process wastewater
streams at existing sources (flow of 10 lpm or greater and VOHAP
concentration of 1000 ppmw) represent the maximum reduction achievable
considering costs and other impacts. More stringent control than the
proposed levels would not reduce HAP emissions significantly enough to
warrant the increase in control costs.
Alternative control Options 2 through 4 were not selected because
the additional emission reduction achieved through further control was
not significant, given the costs and the uncertainty regarding the
characterization of SOCMI wastewater systems. Specifically, control of
wastewater streams with a flow rate of 5 lpm or greater and a VOHAP
concentration of 800 ppmw (Option 2) was estimated to result in about
700 Mg/yr (770 tons/yr) additional reduction at a cost of about $2.9
million/yr. This control option has an incremental cost effectiveness
of $4,300/Mg ($3,900 ton). Options 3 and 4 achieve only a small
additional emission reduction at incremental cost effectiveness values
of $13,400/Mg and $24,000/Mg ($12,100/ton and $21,600/ton). Given the
technical uncertainties that exist regarding the representation of
SOCMI wastewater streams and industry practices in design of wastewater
collection and treatment systems, it is uncertain whether any of the
alternative control options considered would result in additional
emission reductions.
The regulatory alternatives considered for process wastewater
streams at new sources were a combination of the floor control
requirement for organic HAP's with volatilities similar to benzene (see
table 8 of subpart G for the list of organic HAP's) and control
alternatives for the less volatile organic HAP's (see table 9 of
subpart G for the list of organic HAP's). Table 7 shows the emission
reductions and costs associated with the floor control for the table 8
organic HAP's combined with the emission reduction and costs for
control of total VOHAP concentrations of either 1,000 ppmw (Option 2)
or 5 ppmw (Option 3). After considering the alternatives and the final
emission and control costs, the EPA concluded that the control
requirements in Option 2 are achievable. The control requirements for
new source wastewater streams would apply to 3 sets of streams: Streams
with flow rates of 0.02 lpm or greater and a VOHAP concentration of 10
ppmw or greater of organic HAP's listed in table 8 of subpart G; and
streams with a flow rate of 10 lpm or greater and a VOHAP concentration
of 1000 ppmw or greater of organic HAP's listed in table 9 of subpart
G; and any stream with a VOHAP concentration of 10,000 ppmw or greater
of organic HAP's listed in table 9 of subpart G. The control level was
selected considering the emission reduction achieved by the alternative
control options for HAP emissions and considering the criteria
enumerated in Section 112(d) of the Act.
The control requirements of Option 2 are estimated to achieve an
emission reduction of 13,500 Mg/yr (14,800 tons/yr) compared to
emissions in absence of this rule. This represents an 82 percent
reduction from uncontrolled emission rates. The annual cost to achieve
this reduction is about $12.8 million. Option 2 is estimated to achieve
an emission reduction of about 3,200 Mg/yr (3,500 tons/yr) of HAP
emissions above Option 1 (the floor). This control would cost an
additional $2.8 million/yr with an average cost-effectiveness value of
$948/Mg ($860/ton).
A more stringent level of emission limitation was not selected
because control beyond Option 2 is estimated to achieve only a small
additional emission reduction. The further control would reduce
emissions by an additional 400 Mg/yr (440 tons/yr) of HAP and would
cost about $24 million per year, an increase of about $11 million per
year over the cost of Option 2. Because the cost is disproportionately
large compared to this additional emission reduction, the EPA did not
select the more stringent control option for the standard.
b. Summary of control decisions. In summary, the selected control
provisions are estimated for the well- characterized processes to
reduce emissions from existing sources by 312,000 Mg/yr (343,000 tons/
yr) and new sources by 61,300 Mg/yr over emissions that would occur in
absence of this rule. The cost of this control is estimated to be about
$107 million/yr for existing sources and $32,300/yr for new sources.
The cost of the monitoring, recordkeeping and reporting requirements
associated with the controls is estimated to be $68 million/yr. Tables
6 and 7 also show the emission reduction and cost associated with the
maximum reduction that could be achieved. For existing sources, only an
additional 10,000 Mg/yr (11,000 tons/yr) emission reduction could
result, and this would cost an additional $103 million/yr. Similarly,
for new sources, the additional emission reduction is about 400 Mg/yr
(670 tons/yr) and this would cost $19 million/yr more than the selected
control requirements. The EPA considers the selected standard to be the
maximum reduction achievable considering costs and other impacts. [As
discussed in previous sections, the EPA is deferring decision on
control of medium-sized storage vessels at existing sources. Thus, the
costs and emission reductions presented in table 6 may be slightly
overstated.]
3. Selection of Requirements
a. Process vents. This section discusses the following issues
related to the selection of requirements for process vents: 95-percent
control vs. 98-percent control for existing sources, 98-percent control
for existing sources, 98-percent control for organic HAP's, and the
halogenated stream limit.
(i) 95-Percent Control vs. 98-Percent Control for Existing Sources.
For the final rule, the EPA maintains the same position as at proposal
that existing control devices must achieve an organic HAP reduction of
98 percent or 20 ppmv (measured as total organic HAP or TOC).
Several commenters suggested that facilities with an existing
control device achieving 95 percent reduction be allowed to operate for
a period of time (e.g., 10 years) or until a replacement is necessary.
One commenter acknowledged that emissions averaging could be used to
make up the difference between 95 percent and 98 percent, but that
emissions averaging may not be a viable option in all cases, for
example at small production facilities.
Available information shows that controls achieving 98 percent
reduction for Group 1 process vents are in use at a significant number
of existing sources, and are part of the MACT floor. Thus, the standard
must require 98-percent reduction. This level of control is required by
previous NSPS and several state regulations. For those existing process
vent control devices that are achieving less than 98 percent, the EPA
has provided emissions averaging as an alternative compliance option.
An emission credit from control of another emission point in the
facility can be used to offset the emission debit generated by the use
of a process vent control device with less than 98 percent efficiency.
For small production facilities, the magnitude of emission debit
generated by controlling process vents to efficiencies lower than 98
percent should be small. Therefore, emissions averaging should still be
a viable option for these facilities. Facilities may also have other
options for control of Group 1 process vents. In some cases, addition
of supplemental fuel and modification of control device operating
conditions can allow existing devices to achieve 98 percent. In other
cases, process modifications to raise the TRE to greater than 1.0 may
also be a feasible means of compliance.
(ii) 98-Percent control for organic HAP. For the final rule, the
EPA maintains the same position as at proposal that the reference
control technology (RCT) of combustion can achieve at least 98-percent
reduction for total organic HAP. The 98-percent reduction level applies
to both process vents and transfer operations.
One commenter said that the EPA had not demonstrated that RCT
achieves a 98-percent reduction for each HAP and that the efficiency
appeared to be based on VOC control levels for previous NSPS. However,
several commenters said that the reduction was achievable or that the
RCT can provide greater than 98-percent reduction and that at least
99.9-percent reduction should be required.
The EPA would first like to reiterate that control by thermal
oxidation is not specifically required by the HON process vents
provisions. Thermal oxidation is simply the reference control
technology whose performance level must be met by any controls intended
to comply with the HON process vents provisions. The commenter
correctly states that 98-percent control is based on studies used to
determine VOC control levels for past NSPS and has not been proven by
testing for each individual HAP. These two issues do not weaken the
EPA's decision for 98-percent control of HAP's for the following
reasons: (1) Nearly all HAP's covered by this rule are also VOC's; and
(2) HON compliance is not based upon control of each individual HAP.
Compliance with the HON may be based upon measurements of either total
organic HAP or TOC. Clearly, a control device might have a higher level
of control for one particular HAP than for another, but compliance is
based on the overall reduction of total organic HAP or TOC.
The 98-percent level of control was chosen because it has been
shown to be uniformly achievable by well-designed and operated
combustion devices. As stated earlier, test data to demonstrate
efficiency in a thermal incinerator are not available for each
individual HAP. However, the efficiency conclusions for a thermal
incinerator (98-percent reduction or an outlet concentration of 20
ppmv) were based on test data using the most difficult VOC compounds to
combust, which included several organic HAP's. Therefore, it was
concluded that the 98-percent reduction can be achieved for total
organic HAP for all well-designed and operated systems. The EPA
recognized that thermal incineration may achieve greater than 98-
percent reduction in some cases, but test data shows that levels
greater than 98 percent may not be uniformly achievable under all
operating conditions.
(iii) Halogenated streams limit. For the final rule, the EPA has
determined that a mass limit is more appropriate for identifying
halogen streams that require control of acid gases. The mass limit
format will result in a more efficient control approach for acid gas
formation and will provide greater flexibility for compliance. This has
been changed from proposal where a halogen stream was defined by a
concentration limit.
Several commenters requested that a mass limit be used in lieu of a
concentration for determining if a process vent stream was halogenated
or nonhalogenated so multiple process vent streams could be controlled
in a common header system. Several commenters also requested a mass
limit so flares could be used to control vent streams which contained a
small mass rate of halogen compounds. Some commenters cited an existing
state regulation in Texas and RCRA rules that were based on a mass
limit. Other commenters objected to the requirement to use a scrubber
following a combustor to achieve the specified halogen reduction. They
noted that other control device combinations, such as a scrubber before
a flare, could achieve the same results for some process vent streams.
The EPA agrees with the commenters, and a mass limit for defining
halogen streams was incorporated in the final rule. The mass limit will
provide greater flexibility for compliance. The data used to evaluate
the proposed concentration limit were used in this reassessment to
determine a mass limit for promulgation. This change is consistent with
the demonstrated scrubber performance and not a change in the intended
stringency of the rule. The rule has been revised to define a
halogenated stream as a process vent stream containing 1.0 lb/hr or
greater of halogen atoms. If Group 1 halogenated streams are combusted,
the rule requires a 99-percent reduction of total halogen and hydrogen
halides or a reduction of halogen and hydrogen halide emissions to less
than 1.0 lb/hr. If halogen controls were installed prior to proposal,
these are required to achieve 95-percent reduction or reduce emissions
to 1.0 lb/hr. A commenter noted that State rules require 95-percent
control. The EPA did not include costs for replacing existing scrubbers
that achieve between 95- and 99-percent removal in the national impact
estimates, and it would not be reasonable to require replacement of
existing scrubbers given the small additional percent emission
reduction that would be achieved.
The rule has been reworded so that only the emission limit is
specified rather than also specifying that a scrubber must be used
after a combustor. The rule has also been reworded to allow owners or
operators flexibility to reduce halogen atom mass flow rate of a Group
1 process vent stream to less than 1.0 lb/hr before combustion (thereby
becoming nonhalogenated) and use any type of organics control device
(including a flare) to combust the stream.
b. Storage Vessels--(i) Vapor pressure criteria for large storage
vessels--The final rule maintains the same applicability criteria
(i.e., vapor pressure and storage vessel size) that were specified in
the proposed rule as MACT for large storage vessels located at both new
and existing sources.
Two commenters requested that the vapor pressure criterion for
determination of Group 1 status of large storage vessels be increased
(i.e., reduced in stringency). The commenters objected to the EPA's
selection of options above the floor because, in the commenters' view,
the options were not cost-effective. The commenters asserted that the
EPA's cost analysis had underestimated the actual cost of compliance by
underestimating the following costs:
(1) The cost of cleaning and degassing storage vessels;
(2) The capital cost for IFR's;
(3) The installation cost for retrofitting fixed roof tanks with
IFR's; and
(4) The cost for installing a condenser on a fixed roof storage
vessel.
Regarding the cost of cleaning and degassing storage vessels, the
commenters contended that the EPA's cost estimate was low because: (1)
It did not include the cost of hazardous waste disposal; and (2) it was
based on the cost of cleaning and degassing tanks containing gasoline
and light petroleum products. Regarding the cost of IFR's, the
commenters contended that the EPA's capital costs for the installation
of IFR's were low for two reasons: (1) The EPA's estimated capital
costs, which are based on vendor quotes, were lower than the vendor
quote obtained by the commenter; and (2) in general, vendor quotes
underestimate the installation costs for IFR's because they do not
account for additional tank repairs that are discovered after the tank
has been emptied and cleaned for retrofit. Regarding the cost of
installing a condenser on a fixed roof storage vessel, one commenter
contended that the EPA's cost did not incorporate additional start-up
costs, such as testing the operation of a new condenser after
installation.
The EPA determined that the costing equation used in the proposal
analysis for cleaning and degassing should be revised to include the
cost of hazardous sludge disposal. These costs have been incorporated
into the impacts analysis for the final rule. Regarding the EPA's
costing equation for cleaning and degassing storage vessels (including
hazardous sludge disposal), the EPA had its equation reviewed prior to
proposal by companies that perform cleaning and degassing for the
chemical industry. The EPA concluded that the equation is
representative of the cost for the chemical industry. The commenters
did not provide adequate detail to demonstrate that the cost for the
chemical industry would generally be higher than EPA's estimate.
The EPA determined that the commenters' capital cost estimates for
internal floating roofs are higher than EPA's estimates because the
commenters were addressing the capital cost of fiberglass internal
floating roofs. The EPA's analysis was based on aluminum internal
floating roofs, which are much less expensive than fiberglass IFR's.
However, if at baseline a fixed roof storage vessel stores a liquid
that is not compatible with an aluminum IFR, the EPA estimated the cost
of installing a condenser, rather than a fiberglass IFR, for the fixed
roof vessel. The EPA's cost of a refrigerated condenser is, on average,
equivalent to the cost for a fiberglass IFR.
The EPA's cost equation for installing an IFR on a fixed roof
storage vessel, which is based on vendor quotes, already accounts for
those tank changes that are directly associated with the installation
of the IFR (i.e., the cost of cutting openings and vents). The EPA does
not consider the additional tank changes suggested by the commenters
(e.g., upgrading the column supports) to be directly related to the
retrofit or to be applicable to the average retrofit for compliance
with the rule. Therefore, the EPA will continue to utilize its vendor
quotes for installation costs for IFR's.
The EPA determined that it had underestimated the start-up costs
for installing condensers on fixed roof storage vessels (e.g., the cost
of testing a new condenser to ensure that it achieves the required
temperature). In the proposal analysis, the EPA had used the costing
factor provided in the EPA's OCCM: Chapter 8--Refrigerated Condensers
published in November 1991, for installing a packaged condenser system.
This factor did not account for the start-up cost mentioned by the
commenters. The EPA has revised its installation cost equation for
condensers to include the OCCM's costing equation for installing a
nonpackaged condenser system. This revised equation accounts for the
additional start-up costs for installing a condenser.
(ii) Performance of existing control equipment on storage vessels
at existing sources. For the final rule, the EPA has revised its
assessment of the performance achievable by the control equipment for
storage vessels at existing sources. Refer to section V.C.2. of this
preamble for further discussion of how this issue relates to the MACT
floor for existing sources.
Two commenters recommended changing the RCT requirement for
condensers to specify 90-percent control for storage vessels at
existing sources. The commenters contended that most existing
refrigerated condensers on storage vessels at existing sources can
achieve only 90- to 93-percent control and would therefore have to be
replaced with new condensers that could achieve 95-percent control.
The EPA has concluded that most existing refrigerated condensers
serving storage vessels at existing sources are achieving 90- to 93-
percent control. At proposal, the EPA had assumed that these existing
condensers could be adjusted to achieve 95-percent control through
changes in coolant temperature. However, after reevaluating the
available information, the EPA has concluded that not all of the
existing condensers achieving 90-percent control can be adjusted to
achieve 95-percent control. Additionally, the EPA has determined that
IFR's controlling emissions from fixed roof storage vessels at existing
sources do not have controlled fittings.
Therefore, the final rule establishes MACT for storage vessels at
existing sources as 95-percent emissions reduction, except where
control devices achieve 90- to 95-percent emissions reduction. The
final rule does not require upgrade of an existing control device,
provided the device was installed on a storage vessel on or before
December 31, 1992 and is designed to reduce inlet emissions of total
organic HAP's by at least 90 percent. Refer to section V.C.2. of this
preamble for further discussion of how this issue relates to the MACT
floor for existing sources.
c. Transfer operations. The analysis of the MACT floor level of
control and the control requirement for transfer operations did not
change for the final rule. Owners or operators of transfer racks that
load 650,000 l/yr or more of organic HAP's with a rack-weighted partial
pressure of 10.3 Kpa or greater are required to control emissions by
98-percent reduction, use a flare, or use vapor balancing. Facilities
using vapor balancing can also choose to exclude the rack being vapor
balanced from compliance with the transfer provisions.
Some commenters supported the stringency level set for transfer
operations, including the definitions of Group 1 and Group 2 transfer
racks, the level of control (i.e., 98 percent), and the allowance of
vapor balancing. However, one commenter contended that the EPA did not
identify the best-controlled transfer racks. The commenter asserted
that the EPA identified vapor balancing as a superior control
technology since transfer racks using this technology are exempt, but
the EPA did not identify vapor balancing as the floor or MACT.
Based on the data available for the floor analysis, the EPA
concluded that the average of the top 12 percent of the transfer racks
achieve 98-percent reduction. The 98-percent value was based on racks
subject to the Benzene Waste NESHAP. Using vapor balancing with vapor
collection on a transfer rack exempts the facility from the HON
transfer provisions because vapor balancing reduces emissions by 98
percent or better, based on a technical analysis. However, data were
not available to identify if vapor balancing was being used on a
sufficient proportion of SOCMI transfer operations to constitute a
floor level of control.
d. Process wastewater--(i) Lists of hazardous air pollutants.
Several commenters requested clarification of the difference in the
lists of organic HAP's: (1) In the Act; (2) in table 2 of subpart F;
and (3) in tables 8 and 9 of subpart G. The EPA clarifies that the Act
includes a list of 189 HAP's from which the EPA has identified 112
organic HAP's that are emitted from SOCMI processes (table 2 of subpart
F). From the list of 112 organic HAP's in table 2 of subpart F, the EPA
has identified 76 organic HAP's that exist in water and that are most
likely to be emitted from wastewater. These 76 organic compounds are
listed in table 9 of subpart G. Table 8 of subpart G is a subset of
table 9 and includes organic HAP's that volatilize from wastewater at a
rate approximately equal to or greater than benzene.
(ii) Definition of ``wastewater.'' In the proposed rule, the
definition of ``wastewater'' contained several terms including process
fluid, process wastewater, maintenance wastewater, and maintenance-
turnaround wastewater. These terms were defined within the proposed
definition of ``wastewater.''
In the final rule, the EPA has revised the definition of wastewater
in Sec. 63.101 of subpart F to clarify the scope of the EPA's original
intent. As part of this clarification, the term ``process fluid'' has
been removed from the definition of ``wastewater,'' because commenters
were confused that process fluids were considered to be wastewater
before they left the process unit equipment and entered the individual
drain system. The EPA clarifies that any fluid must exit the process
unit equipment before it may be a wastewater stream subject to the HON.
The term ``maintenance-turnaround wastewater'' also has been deleted
from the definition of ``wastewater'' because all maintenance-related
wastewater is now included in the definition of ``maintenance
wastewater.'' In the final rule, the definitions of both ``wastewater''
and ``maintenance wastewater'' are in Sec. 63.101 of subpart F. The
revised definition of ``wastewater'' in the final rule reads as
follows:
Wastewater means organic hazardous air pollutant-containing
water, raw material, intermediate, product, by-product, co-product,
or material that exits equipment in a chemical manufacturing process
unit that meets all applicability criteria specified in Sec. 63.100
(b)(1) through (b)(3) of subpart F and either: (1) Contains at least
5 ppmw total volatile organic hazardous air pollutants and has a
flow rate of 0.02 lpm or greater; or (2) contains at least 10,000
ppmw total volatile organic hazardous air pollutants at any flow
rate. Wastewater includes both process wastewater and maintenance
wastewater.
Numerous comments were received on the definition of ``wastewater''
in section 63.101 of subpart F. All responses to these comments are
located in Sec. 4.1.2 of BID volume 2B. Commenters expressed concern
about the following issues:
(1) The EPA should specify a percentage of water in order for a
stream to be considered a wastewater subject to the HON;
(2) The definition of ``wastewater'' should not include ``process
fluid,'' ``product,'' and ``intermediate stream''; and
(3) The EPA should narrow the scope of the wastewater definition
because products that are within a process unit should not be
regulated.
The EPA has not specified a percentage of water that must be
present in a wastewater stream in order for the stream to be a
wastewater stream. The EPA intends for the HON to regulate as
wastewater any stream that: (1) Exits process unit equipment; and (2)
meets the concentration and flow rate criteria that are specified in
the definition of wastewater. The EPA has determined that such
wastewater streams have a significant potential for emissions and
should therefore be regulated.
Because the EPA intends to regulate wastewater streams that are
generated when organics exit process unit equipment, the EPA continues
to include the terms ``product'' and ``intermediate'' in the definition
of ``wastewater.'' If an owner or operator chooses to discharge from
process unit equipment either a product or intermediate that also meets
the definition of a ``wastewater'' (i.e., flow rate and VOHAP
concentration), the EPA wants to ensure that emissions from such
wastewater streams are controlled. If a product or intermediate stream
has not exited the process unit equipment, then such streams cannot
meet the definition of ``wastewater'' in Sec. 63.101 of subpart F, and
therefore are not subject to the wastewater provisions in the HON. The
EPA has deleted the term ``process fluids'' from the definition of
``wastewater'' because commenters stated that process fluids also could
mean fluids within a process unit.
(iii) Basis of standard. In the final rule, the EPA retains steam
stripping as the RCT. Numerous commenters opposed basing control of HAP
emissions from wastewater on steam stripping and recommended biological
treatment as the RCT for the following reasons:
(1) The most common type of wastewater treatment currently employed
by existing SOCMI sources is biological treatment;
(2) Many of the HAP's listed in table 9 of subpart G are not
volatile and cannot be removed by steam stripping, but can be
biologically degraded; and
(3) The inclusion of biological treatment as an RCT would be
consistent with the Benzene Waste NESHAP requirements.
The EPA selected steam stripping as the RCT because it is the most
universally applicable treatment technology for removing volatile
organic HAP's from wastewater. The EPA is aware that many SOCMI
facilities use biological treatment units for wastewater treatment.
However, in general, compounds that are not easily steam stripped, but
are readily biodegraded, are not being regulated by the HON. The HON
regulates volatile organic HAP's and volatile organic HAP's can be
treated by steam stripping. Not all of the regulated compounds are
significantly biodegradable, because volatility does not correlate with
biodegradation efficiency, as it does with steam stripping efficiency.
When reviewing biological treatment as the potential RCT, the EPA
determined that variability in performance is significant. For example,
the amount of emissions reduction achieved by biological treatment,
even for biologically degradable compounds, will vary among SOCMI
sources due to ranges in operating and design parameters, such as the
biological degradation rate, surface area of the unit, aeration rate,
hydraulic residence time, and the active biomass concentration. A well-
operated and well-maintained biological treatment system can achieve
reductions as high as 99-percent HAP destruction. However, the
variability in performance makes it difficult to quantify a required
emission reduction for the purpose of setting a standard. Emission
reductions for biological treatment systems can only be determined on a
site-specific basis. The EPA emphasizes that SOCMI sources using
biological treatment can comply with the rule by consistently achieving
the required emission reduction.
The EPA has reviewed the Benzene Waste NESHAP and has determined
that the equipment standard for the use of a biological treatment unit
in the Benzene Waste NESHAP would not achieve comparable emission
control for all 76 HAP's regulated by the HON wastewater provisions.
This option may be used in combination with other treatment options,
but all wastewater streams must be conveyed or handled in individual
drain systems or waste management units that limit HAP emissions to the
atmosphere as required by Secs. 63.133 through 63.137 of subpart G. The
only wastewater streams that may be conveyed or handled in uncontrolled
individual drain systems or waste management units are:
(1) Group 1 wastewater streams that have already been treated and
have achieved compliance with one of the HON treatment options in
Sec. 63.138 of subpart G; and
(2) Group 2 wastewater streams. As required in the other wastewater
compliance options, facilities using this option must comply with the
emission suppression requirements in Secs. 63.133 through 63.137 for
all wastewater streams except those wastewater streams that are already
in compliance. In the final rule, the EPA has included an additional
compliance option for the use of biological treatment. Under this
treatment option, an owner or operator is required to control all
wastewater streams in accordance with Secs. 63.133 through 63.137 and
achieve a 95-percent reduction in total HAP mass for all wastewater
that is treated in the biological treatment system.
(iv) Clarification on the Use of the Terms ``HAP'' and ``VOHAP''.
In response to comments, the EPA clarifies the use of the terms ``VOHAP
concentration'' and ``HAP'' to reflect the proper use of the terms
throughout the preamble, regulation, and BID documents. The terms
``volatile organic hazardous air pollutant concentration'' or ``VOHAP
concentration'' mean the concentration of an individually-speciated
organic HAP in a wastewater stream or a residual as measured by Method
305. The term ``VOHAP concentration'' does not refer to the lists of
organic HAP's in tables 8 and 9 of subpart G. The wastewater provisions
of the HON regulate emissions from wastewater of those organic HAP's
listed in table 8 for new sources and in table 9 for new and existing
sources. The applicability of the requirements in the HON to wastewater
streams is based on the VOHAP concentration of the HAP's present in the
wastewater stream. In addition to using Method 305, the VOHAP
concentration of a compound can be calculated by multiplying the HAP
concentration of the compound by the compound-specific fraction
measured (Fm) value listed in table 34 of subpart G.
(v) Point of Generation. In the final rule, the conceptual basis
for the point of generation has not changed from the proposed rule.
However, in consideration of the comments, the EPA has clarified the
definition. The point of generation is located where process wastewater
exits the chemical manufacturing process unit equipment.
Numerous commenters requested clarification on both the proposed
definition of ``point of generation'' and the location where sampling
for the flow rate and VOHAP concentration were permissible. The
following comments were submitted:
(1) The EPA should not define the point of generation as ``prior to
mixing'';
(2) The point of generation should be after the last recovery
device and before discharge to a wastewater treatment or disposal
system;
(3) The EPA should delete or explain the use of the term ``integral
to the process unit'';
(4) The EPA should clarify that the point of generation is at the
point where material exits the process unit and enters the individual
drain system;
(5) To be consistent with RCRA, the point of generation should be
the first point downstream of the process unit where emissions can
enter the atmosphere; and
(6) Sampling should be allowed downstream of the point of
generation in situations where the point of generation is either within
a closed-pipe system or sampling could be dangerous to workers.
The basic foundation of the proposed provisions for process
wastewater is to identify wastewater streams for control and treatment
based on VOHAP concentration and flow rate at their point of
generation, which is where the wastewater exits chemical manufacturing
process unit equipment. This approach focuses control efforts on the
wastewater streams with the highest HAP loadings. If dilution prior to
a control determination were allowed, some wastewater streams that
would have required control based on the VOHAP concentration criteria
would not meet the VOHAP concentration criteria at the point of
generation for control and would not be treated. Thus, the EPA has
retained the concept of ``prior to mixing'' to avoid the dilution of
wastewater streams. However, the EPA allows the owner or operator to
make corrections for changes in VOHAP concentration and flow rate using
engineering calculations.
In consideration of commenter concerns, the final rule clarifies
the EPA's original intent in Sec. 63.144 of subpart G to reduce the
sampling and analysis burden for industry while still meeting the EPA's
objectives. The point of generation remains a single location in the
final rule. However, sampling to determine the characteristics of a
wastewater stream (i.e., VOHAP concentration and flow rate) may be
accomplished either at the point of generation or downstream of the
point of generation. If wastewater characteristics are determined
downstream of the point of generation, the owner or operator must
correct for:
(1) HAP losses due to volatilization;
(2) Reduction of VOHAP concentration or changes in flow rate by
mixing with other water or wastewater; or
(3) Reduction of VOHAP concentration or flow rate by treatment or
handling to destroy or remove HAP's.
The final rule also incorporates the concept of designating either
a single wastewater stream or a mixture of wastewater streams as a
Group 1 wastewater stream. This option allows the facility owner or
operator to declare that at a designated location downstream of the
point(s) of generation, all wastewater streams at this location and
upstream are Group 1 and are therefore controlled in accordance with
Secs. 63.133 through 63.137. The owner or operator is required to meet
all requirements for Group 1 wastewater streams, both upstream and
downstream for the designated Group 1 wastewater stream. The advantages
to using this option are that no sampling is necessary to make a Group
1/Group 2 determination and a facility can reduce the number of
locations where wastewater stream characteristics are determined.
By adding the option to designate Group 1 wastewater streams and
clarifying the option to determine wastewater characteristics
downstream of the point of generation, the EPA has addressed commenter
concerns about sampling in closed piping. While the concept of
designating Group 1 wastewater streams does not allow any wastewater
streams that would be Group 1 at the point of generation to become
Group 2 wastewater streams, it does provide an avenue for fewer point
of generation identifications than the proposed rule because sampling
does not need to be done at the actual point of generation.
The EPA encourages owners or operators to sample downstream of the
point of generation if sampling from the point of generation could be
dangerous to workers or if the point of generation is within a closed-
pipe system. In fact, the proposed rule allowed sampling downstream of
the point of generation. Because numerous comments indicated that the
proposed rule was not clear about where to sample and make Group 1/
Group 2 determinations, the final rule has been clarified. The final
provisions now specify that Group 1/Group 2 determinations can be made
downstream of the point of generation using sampling, process
knowledge, or bench-scale or pilot-scale test data.
e. Cooling water. In the final rule, the provisions for monitoring
cooling tower and once-through cooling water systems have been modified
in response to commenter concerns. In the final rule, the EPA clarifies
the definition of heat exchange system (i.e., both cooling towers and
once-through cooling systems). A leak in a heat exchange system is no
longer identified by a statistically significant increase of 1 percent
at a 95-percent confidence level but is identified only by a
statistically significant increase of at least 1 ppm at a 95-percent
confidence level. In the final rule, the EPA clarifies that sampling
for leak detection must be conducted at the inlet and outlet of the
cooling tower, not the inlet and outlet of each heat exchanger. For the
final rule, a once-through cooling system will not be subject to the
HON if it has an NPDES permit with a discharge limit of less than 1
ppm. An NPDES permit with a discharge limit of less than 1 ppm
guarantees that the concentration differential across a once-through
cooling water system is less than 1 ppm. Furthermore, the EPA realizes
that routing the discharge from a steam jet ejector to a cooling tower
may cause a concentration differential of 1 ppm across a heat exchange
system. Therefore, in the final rule, the EPA includes re-routing the
discharge from a steam jet ejector as a means of repairing a leak in a
heat exchange system.
In response to comments requesting clarification about which HAP's
were regulated, the EPA clarifies that water from cooling towers are
regulated for the organic HAP's listed in table 2 of subpart F except
for four water-reactive HAP's and once-through cooling systems are
regulated only for the HAP's listed in table 9 of subpart G.
Several commenters were concerned that 15 days was not ample time
to repair a leak in a heat exchange system. In response to comments,
the EPA has extended the delay of repair for leaks in a heat exchange
system from 15 days in the proposed rule to 45 days in the final rule.
The final rule allows delay of repair beyond 45 days for situations
where the owner or operator can show that emissions from shutdown of a
process would be greater than emissions from the leak.
Several commenters submitted comments stating that the EPA: (1)
Correct or clarify the original intent to require sampling across the
cooling tower, not across each heat exchanger; (2) provide an exemption
for heat exchange systems with low flows; (3) clarify which HAP
emissions are regulated from cooling towers and once-through cooling
water systems; and (4) clearly state which parameters are acceptable
for monitoring. Numerous commenters suggested alternate ways of testing
for a leak in a heat exchange system rather than testing for speciated
HAP's, including testing for TOC or total VOHAP concentration, or using
surrogate parameters to determine a leak. Having reviewed several
sampling parameters and analytical methods, the EPA concludes that: (1)
Sampling for total VOC, total HAP, TOC for semi-volatile compounds, or
speciated HAP concentration is allowable; and (2) any method listed in
40 CFR part 136 or any other method approved by the Administrator may
be used as long as the same method is used on both the inlet and
outlet. The EPA concludes that monitoring of surrogate parameters is
not sufficient to determine the magnitude of the leak in the cooling
tower or once-through cooling system. After analyzing the amount of
HAP's that could be emitted if the sampling frequency for leak
detection were extended beyond quarterly, the EPA continues to require
quarterly monitoring. The rule does not provide an exemption for heat
exchange systems with a low flow rate (e.g., 1,000 to 2,000 gpm)
because the emissions from such systems are significant if a leak is
detected. For example, if a leak at 2,000 gpm is detected after 3
months of leaking, 1.1 tons of HAP emissions could have already been
emitted.
f. Maintenance wastewater. In the final rule, the EPA requires that
all maintenance-related wastewater be managed in the same manner. The
definition of ``maintenance-turnaround wastewater'' has been eliminated
from the final rule and incorporated into the definition of
``maintenance wastewater,'' which now encompasses all maintenance-
related wastewater streams that are subject to the HON. The term
``maintenance wastewater'' in the proposed rule referred to only
routine maintenance wastewater.
Also, in the final rule, all maintenance-related wastewater streams
are subject to the same requirements under the HON. Unlike the proposed
rule, the final rule does not require that routine maintenance
wastewater be managed in a controlled drain system. In the final rule,
the facility's start-up, shutdown, and malfunction plan must include a
description of procedures that will ensure that all maintenance
wastewater is properly managed and HAP emissions are controlled. These
requirements are consistent with what was proposed for maintenance-
turnaround wastewater.
The EPA received numerous comments opposing the proposed
maintenance wastewater provisions, including: (1) Maintenance-related
wastewaters are not a significant source of HAP emissions; (2) the
control of maintenance wastewater cannot be justified; and (3) there
should be a Group 1/Group 2 determination or a de minimis level to
determine which maintenance wastewaters are subject to the regulation.
Several commenters expressed confusion about the proposed requirements
for routine maintenance wastewater and whether or not these maintenance
wastewaters were required to be collected in a closed or controlled
drain system. Numerous commenters suggested that the requirements for
routine maintenance wastewater and maintenance-turnaround wastewater be
the same.
In the proposed rule, the EPA's original intent was to require good
work practices and reduce the burden of implementing the rule by
deleting the requirement that the owner or operator must determine if
emissions from maintenance wastewater have exceeded a designated de
minimis level. Based on comments received, all maintenance-related
wastewater is now subject to the same requirements. The EPA is
eliminating the provisions which require that routine maintenance
wastewater be managed in a controlled drain system. The EPA is not
including a Group 1/Group 2 or de minimis level criteria for
maintenance wastewater because of the difficulty in determining the
concentration and flow rate and the difficulty of enforcement.
D. Emissions Averaging
This section of the preamble presents the rationale for the
emissions averaging provisions (described in section 63.150 of subpart
G) and the alternative policies that were considered in developing
these provisions.
As part of the EPA's general policy of encouraging the use of
flexible compliance approaches where they can be properly monitored and
enforced, the Administrator is allowing sources the option of using
emissions averaging to comply with subpart G. Under particular
circumstances, emissions averaging can provide sources the flexibility
to comply in the least costly manner while still maintaining a
regulation that is workable and enforceable. The EPA's goal in crafting
the emissions averaging provisions in the final rule has been to make
emissions averaging available to sources faced with some emission
points that are particularly difficult or costly to control. At the
same time, the EPA has simplified and streamlined the emissions
averaging provisions in order to ease the enforcement burden on
implementing agencies.
The rationale for the specific provisions of the emissions
averaging policy is detailed below. In general, the basic structure of
the HON emissions averaging policy remains much the same as at
proposal. Fundamental elements such as the credit/debit system, kinds
of emission points allowed in averages, reference control efficiency
provisions, provisions for approval of new devices, and an annual
compliance period remain unchanged.
However, some provisions have been altered or added in order to
sharpen the focus of emissions averaging, ease implementation and
administration, and ensure at least the same air quality benefit as
point-by-point compliance. For example, the number of emission points
that can be included in an average has been limited; banking of credits
has been disallowed; actions taken prior to November 15, 1990 or in
response to another State or Federal requirement will not be credited;
averaging will not be allowed at new sources; and a discount factor of
10 percent will be applied to credits generated by control other than
pollution prevention measures. In addition, sources must demonstrate,
to the implementing agency's satisfaction, that a proposed averaging
plan will not cause an increase in risk or hazard relative to point-by-
point controls. All of these changes are discussed in greater detail in
the following sections.
The EPA included this limited emissions averaging system in the HON
to provide sources with flexibility on ways to comply with this
standard. The EPA will continue in future standards to seek ways to
provide sources with flexibility, while maintaining sources'
accountability for meeting health and environmental goals. However, the
HON emissions averaging system, and its provisions for interpollutant
trading, should not be viewed as setting a precedent for future MACT
standards. Moreover, emissions averaging is only one way to provide
sources with flexibility. The EPA will determine the proper amount and
type of flexibility based on considerations specific to each standard.
1. Legal Basis and Scope of Emissions Averaging
a. Legal basis of emissions averaging. For the final rule, the EPA
maintains the position that the Administrator has legal authority to
permit sources to comply with the requirements of section 112(d)
through emissions averaging.
Several commenters agreed that the legal basis for emissions
averaging is sound, citing justifications such as:
(1) Emissions averaging is consistent with section 112(d) of the
Act because cost must be considered in setting MACT standards;
(2) Section 112(h) requires that a numerical emission limit be
promulgated where feasible, leaving it to individual sources to meet
the limit; and
(3) Averaging will achieve equivalent or greater emission
reductions than the rule without averaging.
A number of commenters contended that emissions averaging violates
the law. Some did not consider it a permissible application of MACT.
Others argued that because Group 1 points are left uncontrolled or
undercontrolled under averaging, the rule would fail to achieve the
maximum achievable emission reductions required under section 112(d).
More commenters considered it doubtful that emissions averaging can
achieve the same emission reductions as the rule without averaging, and
claimed therefore that it does not represent an equivalent compliance
option. Some commenters argued that the EPA does not have statutory
authority to allow emissions averaging, and that because Congress
specified the use of offsets in section 112(g) and not in section
112(d), it is unlikely that averaging was intended for MACT standards.
Following a thorough review of all the comments received on this
issue, the EPA has concluded that emissions averaging is legally
permissible under section 112.
As stated at proposal, section 112(d) requires standards to be
established for each category or subcategory of sources listed under
section 112(c). Such standards shall then be applicable to sources
within those categories or subcategories. The statute does not define
``source category,'' nor does it impose precise limits on the
Administrator's discretion to define ``source.'' In this case, the
Administrator has exercised that discretion to define ``source''
somewhat broadly to include all emission points relating to SOCMI
production at a facility.
In setting the standard for a category or subcategory, the
Administrator is required to determine a floor for the entire category
or subcategory, and then set a standard applicable to each source
within that category that is at least as stringent as the floor and
requires the maximum achievable emission reductions considering certain
factors. In determining whether the standard should be more stringent
than the floor and by how much, the Administrator is to consider, among
other factors, the cost of achieving the additional emission
reductions. The statute does not limit how the standard is to be set
beyond requiring that it be applicable to all sources in a category, be
written as a numerical limit wherever feasible, and be at least as
stringent as the floor. Therefore, the relevant statutory language is
broad enough to permit the Administrator to exercise discretion to
allow sources to meet MACT through the use of emissions averaging
provided the standard applies to every source in the category,
averaging does not cross source boundaries, and the standard is no less
stringent than the floor. In this rule, the Administrator has created
an averaging system that stays within those legal parameters. The
source has been defined to include all SOCMI processes within a major
source, and a standard has been written to apply to all sources in the
category as provided by sections 112(d) (1) and (2). This standard is
no less stringent than the floor for the category, calculated in
accordance with section 112(d)(3), and takes cost and other relevant
factors into consideration. The standard applies only to sources in the
category, applies to all such sources, is written as a numerical limit
where feasible, and averaging can only be conducted within the confines
of each individual source, thus ensuring that the standard, as applied
to each source, is no less stringent than the floor. In addition, a
discount factor is applied when averaging is used, which further
ensures that averaging will be at least as stringent as the rule
without averaging.
Some commenters on the supplemental notice argued that the
provisions for limiting the number of points, requiring a hazard or
risk determination, and allowing States to exclude emissions averaging
without having to follow the section 112(l) rule approval processes are
inconsistent with E.O. 12866 (September 30, 1993). The commenters
claimed that the Executive Order directs agencies to: (1) Develop
regulations that do not impose unacceptable or unreasonable costs; and
(2) identify and assess available alternatives to direct regulation,
including providing economic incentives to encourage the desired
behavior. The EPA maintains that the rule adheres to the spirit of the
Executive Order throughout, both by providing the most flexible
emissions averaging program that is still enforceable and by allowing
numerous different control options for each kind of emission point
under point-by-point compliance. These two aspects of the rule provide
flexibility to reduce emissions in the most cost-effective manner as
encouraged in the Executive Order.
b. Emission points allowed in averages. Emissions averaging is
allowed across all the emission points, except equipment leaks, within
a single existing source, as ``source'' is defined for the SOCMI source
category. As such, emissions from the following kinds of emission
points can be averaged: process vents, wastewater operations, storage
vessels, and transfer operations. Averaging is allowed across these
four kinds of emission points in order to provide as much flexibility
as possible while maintaining an enforceable standard.
No commenters explicitly expressed support for the selection of
these particular kinds of emission points to be included in emissions
averages. However, the EPA does not interpret this to mean that there
was no support. Rather, it is reasonable to assume that commenters who
supported emissions averaging in general, but did not explicitly
comment on the kinds of emission points available for averaging,
supported allowing averaging across all the kinds of points included in
the proposal.
While some commenters supported the exclusion of equipment leaks
from emissions averaging, a number of commenters expressed direct
support for allowing equipment leaks in emissions averages. They argued
that it is already possible to quantify emissions from equipment leaks
sufficiently and suggested ways to establish baseline levels and to
overcontrol equipment leaks for credit. However, the EPA has determined
that, although methods are available for quantifying emissions from
equipment leaks, equipment leaks cannot be included in emissions
averages at this time because: (1) The negotiated standard for
equipment leaks has no fixed performance level; and (2) neither a
reference control efficiency nor allowable emission levels can be
established for leaks. Without a reference control efficiency or
allowable emissions, debits and credits cannot be established.
A few commenters recommended excluding wastewater from averaging as
well, because they considered accurate or reliable estimation of
wastewater emissions unlikely or impractical. However, the EPA
considers the methods for estimating wastewater emissions to be
sufficient for averaging. The reliability of estimations is assured
because all sources will be using the same emissions estimation
approach. The calculation procedures are specified in Sec. 63.150 of
subpart G. Also, the final rule clarifies that wastewater streams
treated in biological treatment units cannot be used in averages, which
was one of the primary concerns raised by commenters.
Several commenters also opposed allowing averaging across different
kinds of emission points, and recommended that averaging should only be
allowed among the same kinds of points. Some of these commenters were
concerned that the four kinds of emission points have such different
emission characteristics that averaging across the points could alter
the dispersion of emissions and thus, their associated impacts. Other
commenters were concerned that differences in emission estimation
techniques across different kinds of points could be used to calculate
credits that may not reflect actual emission reductions.
The EPA agrees that characteristics of emission points may affect
the dispersion of emissions and associated impacts. However, these
differences exist under point-by-point compliance as well, and it is
equally likely that emissions averaging could decrease impacts as well
as increase them. Similarly, the EPA acknowledges the potential for
significant complexity in averaging across different kinds of emission
points. In order to prevent inappropriate compliance scenarios, the
emissions averaging program relies upon consistent emission estimation
techniques and data from actual operations. In addition, implementing
agencies may require sources to consider differences in dispersion and
associated impacts as part of the risk review that is now required when
approving emissions averages.
c. Averaging at new sources. Emissions averaging is not allowed as
a compliance option for new sources. The decision to limit emissions
averaging to only existing sources represents a departure from the
proposal, which envisaged emissions averaging at both existing and new
sources.
While one commenter specifically supported allowing emissions
averaging at new sources, a number of commenters specifically opposed
allowing averaging at new sources. The EPA concurs with those
commenters who maintained that new sources have historically been held
to a stricter standard than existing sources, because it is most cost-
effective to integrate state-of-the-art controls into equipment design
and to install the technology during construction of new sources. One
reason for allowing averaging is to permit existing sources flexibility
to achieve compliance at diverse points with varying degrees of control
already in place in the most economically and technically reasonable
fashion. This concern does not apply to new sources which can be
designed and constructed with compliance in mind. In addition, as
averaging must be limited to an individual source, there could not be
averaging between new and existing sources, even under the proposal.
Therefore, not allowing averaging at new sources does not affect an
existing sources' ability to use averaging.
d. Broader Scope of Emissions Averaging. In the final rule, the EPA
is retaining the position taken at proposal that emissions averaging
will be permitted only among emission points that are within the SOCMI
source category. The EPA requested comment at proposal on a broader
averaging alternative that would have allowed averaging of emissions
from any point located within a contiguous facility, including both
SOCMI and non-SOCMI emission points. Having considered all of the
arguments put forth by commenters, both supporting and opposing broader
averaging, the EPA has concluded that emissions averaging on a broader
scope cannot be legally justified.
The fundamental problem with the broader averaging approach is that
it allows averaging among multiple sources. The HON has defined the
source, for the purposes of this standard, as the collection of SOCMI
emission points within a major source. Many major sources containing
such points will also contain other points not covered by this standard
but to be covered by later, different MACT standards. Each of these
standards will have a separate floor, and the statute requires that
each standard be no less stringent than its floor. If averaging were
allowed between sources covered by two separate standards, it is likely
that one of the sources involved in the average would be emitting HAP's
at a level that violates the standard applicable to it. Thus, averaging
between multiple sources in different categories is not legally
defensible.
Similarly, allowing averaging between new and existing sources at
the same facility would also likely lead to one source failing to meet
its applicable standard. There are separate MACT standards with
separate floors for new and existing sources within the HON, just as
there will be separate standards for sources in different categories at
the same site. An average that included sources with different floors
and different standards cannot be reconciled with the statutory
requirement that each source in the category comply with the applicable
standard.
The proposal discussed the possibility of defining ``source''
differently for purposes of sections 112 (d) and (i) of the Act. While
the EPA believes that there is broad discretion to define ``source''
under section 112, and the term can quite legitimately have different
meaning in different parts of the Act (see, Chevron, U.S.A. Inc. v.
NRDC, 467 U.S. 837 (1984)), the EPA does not believe that it is
appropriate to apply different definitions in the present context. The
source to which a MACT standard applies under section 112(d) is the
same source that is covered by the compliance requirements of section
112(i). Clearly, section 112(i)(3) provides for setting compliance
dates for categories of sources for which a MACT standard has been set,
and section 112(d) requires standards to be set for categories of
sources. It is not reasonable to argue that compliance with a standard
can be achieved beyond the boundaries of the individual sources that
comprise the category.
2. Interpollutant Trading and Hazard Assessment or Risk Analysis
The emissions averaging provisions in the proposed rule allowed
averaging across all HAP's covered by the HON. The EPA was aware that
these HAP's are associated with a variety of different effects at
different levels of exposure. Therefore, at proposal, comment was
requested on the appropriateness of allowing interpollutant trading in
an unrestricted manner, as well as on two potential approaches for
considering toxicity.
Several commenters maintained that unrestricted interpollutant
trading should be allowed because: (1) So long as pollutants are listed
in section 112(b) of the Act, they should be freely available for
averaging; (2) standards under section 112(d) must be based on the
achievability of control technologies instead of hazard or risk; (3)
accounting for toxicity would add administrative complexity; and (4)
the understanding of HAP toxicity is so limited that adjusting for
trades would be difficult, if not impossible. In contrast, several
commenters criticized interpollutant trading, especially trading that
does not take toxicity into account, citing reasons such as:
(1) It could endanger public and worker health; and
(2) The understanding of HAP toxicity is so limited that
interpollutant trades should not be allowed at all.
In weighing the concerns expressed at proposal, the EPA agrees that
emissions averages should achieve at least a comparable hazard or risk
benefit to point-by-point compliance. At the same time, the EPA
recognizes the inherent difficulty of devising one set of provisions
that would adequately, fairly, efficiently, and simply address these
concerns in all circumstances. After careful deliberation on all
available options, the EPA has decided to require that sources who
elect to use averaging must demonstrate, to the satisfaction of the
implementing agency, that compliance through averaging would not result
in greater hazard or risk than compliance without averaging. This new
provision was introduced in the supplemental notice and has been
included in the final rule.
The EPA will provide a technical support document to aid
implementing agencies in making the demonstration based on existing
procedures, but the actual methodology to be used by the source is to
be chosen by the implementing agency. This approach gives all
implementing agencies the authority to consider hazard or risk in
approving averages.
It was also recognized that to satisfy a State or local agency that
an averaging plan would not increase hazard or risk, a source might
have to identify and quantify all the HAP's included in the average.
Hence, comment was requested on whether identifying all the HAP's in
the emissions streams would pose difficulties for sources, and if so,
what those difficulties would be.
Several commenters responded to the supplemental notice in favor of
requiring sources to conduct hazard or risk assessments claiming that
it would better ensure that public health is protected. However, many
of these commenters still preferred that emissions averaging not be
allowed at all, arguing that: (1) No adequate methodology exists for
assessing and comparing hazard or risk in all circumstances; (2) States
do not have the knowledge or resources to develop the necessary
methodologies; and (3) the new requirement would add to the
administrative burden placed on implementing agencies by the rule.
Still, several commenters insisted that State and local agencies can
and should be allowed to use or develop their own policies and tools
for performing the hazard or risk determination.
The EPA maintains that methodologies exist for assessing and
comparing hazard or risk, which are applicable to this context and
appropriate for many emissions averaging scenarios. However, two points
require clarification. First, the terms hazard and risk should not be
equated. Hazard assessments address toxicity but not exposure. Hazard
refers to the intrinsic toxic properties of a pollutant, such as
potency or the types of toxic endpoints of concern (e.g., cancer,
developmental effects). Risk is an integration of hazard and human
exposure to the pollutant, used to estimate the type and likelihood of
toxic effects associated with a specific pollutant release. Under this
rule, the implementing agency can consider either of these factors in
determining whether an averaging plan should be approved. Furthermore,
the implementing agency may consider ecotoxicity, bioaccumulation, and
acute toxicity exposure to organic HAP's when reviewing a hazard or
risk determination. However, such considerations are not required.
The second point of clarification is that both hazard and risk
assessment methodologies carry with them some uncertainty. The issue of
uncertainty will be addressed in the forthcoming technical support
document. The EPA intends that States should have discretion in
structuring their determinations. States that have existing programs
may wish to continue using their established procedures; in fact, the
new requirement was designed largely because some States already use
hazard or risk assessments to evaluate HAP control. The new requirement
may be seen as an additional burden by some implementing agencies, but
as stated previously, an assessment of hazard or risk is necessary to
determine that averaging does not result in an increase in hazard or
risk.
Several commenters responded in opposition to the provision
requiring hazard or risk assessments and cited some of the reasons
stated at proposal for opposing any kind of toxicity weighting. The
commenters reiterated that: (1) Hazard or risk considerations are
inappropriate in section 112(d) standards, which should be technology-
based; (2) sources' compliance burdens would be increased, which would
decrease the cost effectiveness of using averaging; and (3) there is no
evidence that emissions averaging will increase hazard or risk. Some
commenters on the supplemental notice added that hazard or risk
assessment methodologies are likely to change after the study of risk
assessment by the National Academy of Sciences mandated under section
112(o) of the Act is finished. They argued, therefore, hazard or risk
should not be considered until after the study is submitted.
The floor and the RCT's for the rule were determined without any
consideration of hazard or risk. Emissions averaging represents an
alternative to the technology-based system of point-by-point
compliance, and as an alternative must be demonstrated to result in
equivalent control. This demonstration can consider hazard or risk
without violating the intent of section 112(d) of the Act. It is
possible that in some cases, having to conduct a hazard or risk
assessment may so increase the cost of averaging that it is no longer
more cost-effective to average, but the EPA does not think this is
likely in most cases because of the limited size of most averages. To
address the possibility that an averaging proposal may increase hazard
or risk relative to point-by-point compliance, the EPA intends to
provide a technical support document that could be used for this hazard
or risk demonstration. The EPA recognizes the importance of allowing
States substantial flexibility in designing such a demonstration and
avoiding a burdensome or prescriptive set of requirements that
unnecessarily interfere with averaging. Finally, the Act contains no
requirement that hazard or risk considerations be delayed until after
the study of risk assessment by the National Academy of Sciences is
completed. The statutory requirements and deadlines remain in effect,
the study notwithstanding.
A number of commenters agreed that the EPA should provide standard
guidance on hazard or risk assessments for sources and implementing
agencies. Some commenters recommended that the guidance should: (1)
Take into account different aspects of HAP toxicity, dispersion, and
exposure; (2) resemble guidance for air quality modeling, which defines
different approaches for different situations; (3) be developed with
States involvement; and (4) establish presumptive minimum levels for
State programs to follow. The EPA intends to take these and other
recommendations into account before issuing a technical support
document.
Some commenters supported requiring identification of all HAP's in
emission streams for the purposes of conducting the hazard or risk
assessment because: (1) The capability for doing so is available; (2)
many sources must do so anyway for the purposes of obtaining permits,
paying annual emission fees, and establishing applicability as a major
source; and (3) therefore, the requirement will not entail new data
collection and should not be burdensome. On the other hand, some
commenters opposed having to speciate HAP's in averaged emission
streams because: (1) Concentrations of some HAP's are often below
detection limits; (2) small concentrations are difficult to measure
accurately by many analytical techniques; and (3) it would be
inordinately burdensome to identify all HAP's in wastewater considering
the variability of wastewater streams. Thus, many of these commenters
recommended setting a de minimis level below which a HAP would not have
to be identified. The EPA recognizes that the HAP's in an emission
stream must be identified to a certain extent in order to make the
required demonstration of hazard or risk. The EPA also concurs that it
may not be technically feasible to identify HAP's at levels below some
minimal concentration. The concerns over HAP identification have been
noted and will be considered in developing the technical support
document for approving averages.
3. Limits on Averaging
a. Number of points allowed in averages. The final rule limits a
source to including no more than 20 Group 1 and Group 2 emission points
in an emissions average. Where pollution prevention measures are used
to control emission points to be included in an average, no more than
25 points can be included. For example, if two points to be included in
an average are controlled by the use of a pollution prevention measure,
the source can include up to 22 points in their emissions average.
However, if 6 or more points in the average are controlled by pollution
prevention, the source can include no more than 25 points in their
average.
In contrast, the proposed rule allowed for unlimited averaging. A
number of commenters expressed concern over the difficulty and burden
of overseeing averages of large numbers of points. Some commenters
contended that the resources required to administer the rule with
emissions averaging are much greater than for the rule without
averaging and exceed what can be anticipated from part 70 permit fees.
Because the complexity of averaging across a large number of points
raised significant enforcement concerns, as well as concerns about the
resource burden on implementing agencies, the supplemental notice
solicited comment on limiting averages.
A number of commenters responded to the supplemental notice in
support of limiting the number of emission points, citing the same
concerns as at proposal about the burden and cost of overseeing and
enforcing large averages. In contrast, several commenters considered it
inappropriate to limit averages, arguing that:
(1) The design of the program already limits the number of points;
and
(2) Allowing unlimited averaging would not add much burden to
implementing agencies because most of the burden of monitoring,
recordkeeping, and reporting is borne by the source.
Some commenters noted, and the EPA concurs, that most sources will
not find a large number of opportunities to generate cost-effective
credits. Hence, it can be anticipated that most averages will involve a
limited number of emission points, and imposing a limit should not
affect most sources. The EPA does not agree that the implementing
agency would not bear much of the burden of averaging. The source's
effort to comply with monitoring, recordkeeping, and reporting
requirements will be matched equally by the implementing agency's
oversight and approval.
Some commenters suggested ways to limit averages other than on the
basis of number or percent of points such as: (1) Selecting points to
include or exclude on a case-by-case basis depending on characteristics
of the proposed points and their emissions; (2) excluding wastewater;
or (3) setting a mass limit for a source's emissions on the basis of
allowable emissions. As explained in section V.D.1.b, ``Emission Points
Allowed in Averages,'' of this notice, all emission points except for
equipment leaks are considered appropriate for emissions averaging at
any source subject to the rule. To limit their inclusion based on their
characteristics under case-by-case decisions would add unreasonable
complexity for both the source and the implementing agency. Also, as
discussed in section V.D.1.b of this notice, the EPA maintains that
wastewater emissions points should remain eligible for averaging.
Finally, placing a mass limit on a source would be difficult to enforce
and also add complexity to the rule.
Several commenters considered the proposed range of 5 to 15 points
or 5 to 15 percent of total points arbitrary and claimed there is no
rational basis upon which to base a limit. One commenter advocated
leaving selection of the number or percent limit to the discretion of
the implementing agency. Otherwise, there was no consensus among
commenters on whether the limit should be based on a number or a
percent nor what value in the range was appropriate. The EPA rejected
the choice of a fixed percentage of points at a source because for
larger sources, this could result in hundreds of emission points in
averages, which is unacceptable from an enforcement perspective. The
limit of 20 points in an average, 25 points if pollution prevention
measures are used, was chosen because the EPA anticipates that most
sources will rarely want to include more than 20 points in an average.
In addition, allowing much more than 20 points would make enforcement
increasingly untenable. Thus, the competing interests of flexibility
for sources and enforceability were balanced in this decision. A higher
number of points is allowed where pollution prevention is used in order
to encourage pollution prevention strategies, and because the same
pollution prevention measure may reduce emissions from multiple points.
b. State Discretion. The final rule grants State and local
implementing agencies the discretion to preclude sources from using
emissions averaging to comply with the HON without using the section
112(l) rule approval processes encoded in 40 CFR 63.92 through 63.94.
Without this provision, if a State or local agency wished to receive
delegation of authority to implement and enforce the HON without
averaging, EPA review, according to the procedures in 40 CFR 63.92,
would be required.
Several commenters recommended that State and local agencies be
allowed to exclude emissions averaging because: (1) Averaging may
conflict with their own policies, such as State new source review and
existing programs for controlling HAP's; and (2) the State or local
agency may not have the resources to administer the rule, given the
complexity added by the emissions averaging provisions. The EPA also
recognized that because of statutory limitations, some States do not
have the authority to elect requirements that are more stringent than
Federal standards. States with these statutory limitations might not
otherwise be able to use the rule approval processes [established in
subpart E pursuant to section 112(l) of the Act] to remove emissions
averaging as a compliance option for the HON. Because of these concerns
stated at proposal, the supplemental notice solicited comment on the
advisability of granting State or local agencies the discretion to not
include emissions averaging in their implementation of the rule without
having to go through the section 112(l) rule approval process.
Several commenters responded in favor of the provision granting
States more flexibility in excluding emissions averaging for the
reasons stated in comments on the proposal and also because: (1) Some
States are opposed to allowing emissions averaging due to concerns over
its enforceability and its potential for allowing increased health risk
compared to point-by-point compliance; and (2) it allows States greater
flexibility in implementing the rule. At the same time, several
commenters opposed the provision stating that: (1) States should not
have the option of excluding emissions averaging since they do not have
the option of excluding other provisions of the rule; (2) averaging
does not add much or any administrative burden to States; and (3) if
some States exclude averaging, an uneven ``playing field'' of different
rules would be created, penalizing sources in States that do not allow
averaging.
The EPA maintains that States should have discretion on whether to
allow emissions averaging for the following reasons. First, averaging
increases the complexity of the rule and thus, increases the
administrative burden on State and local agencies. This is an
especially important concern because State and local agencies have
limited personnel and resources. Second, the EPA understands that
averaging conflicts with some existing State programs for regulating
HAP's. Thirdly, because emissions averaging is an alternative
compliance method to the primary control strategy, States should have
the discretion to exclude it as opposed to other provisions that are
essential to the rule and for which no alternative compliance mechanism
has been provided. Even though the EPA supports the use of emissions
averaging where it may be appropriate, its use must be balanced by the
individual needs of States and local agencies that bear the
responsibility for administering and enforcing the rule.
Finally, this provision does not create an uneven ``playing field''
because without this provision, most States could exclude emissions
averaging from their implementation of the HON through the section
112(l) rule adjustment process in 40 CFR 63.92. Including the provision
in the HON will reduce paperwork burdens on States, expedite delegation
of the rule to States, and remove a potential source of uncertainty for
sources subject to the HON.
The section 112(l) rule approval processes require States to make a
demonstration that the State rule is of equivalent or greater
stringency to the Federal rule. For a State rule without averaging, one
component of this demonstration would be to show that the lack of
averaging did not result in the State rule being less stringent than
the Federal rule. The EPA has determined that requiring States to make
this demonstration would be a needless exercise for the following
reason. Today's rule defines both point-by-point compliance and
averaging as acceptable ways of achieving a MACT level of control. If
all sources in a State use the point-by-point compliance method--as
would be the case in a State that implemented HON requirements without
averaging--all sources would be achieving the MACT level of control
required by today's rule. Under today's rule, no source is required to
achieve emissions reductions greater than would be achieved by point-
by-point compliance, and no source is required to use averaging.
Therefore, a State rule that implements requirements of the HON rule
without averaging is equivalent in stringency to the Federal HON rule.
Based on this equivalency finding and today's rule, the EPA is
allowing States to implement the HON unchanged without averaging
through the same processes available to States that wish to implement
the HON unchanged with averaging. Before a title V operating permit
program is in effect in a State, the State may implement the HON
without change through a streamlined procedure in the section 112(l)
rule encoded as 40 CFR 63.91. After the State's operating permit
program is in effect, the State may request delegation of the HON
without change without going through the section 112(l) delegation
processes. Also, based on today's equivalency finding and rule, a State
seeking approval for a State rule that differs from the HON and also
lacks averaging will not have to make a demonstration related to
averaging as part of their equivalency demonstration to satisfy EPA
review under 40 CFR 63.92, 63.93, or 63.94.
Providing these clarifications at this time will benefit sources as
well as States. Without the clarifications, sources might be uncertain
during the section 112(l) approval process about whether averaging
ultimately would be allowed or not, yet would be given no added time
for compliance. The EPA predicts that because of their complex nature,
many HON sources will need the full time period allowed for compliance.
Two commenters objected to the EPA's proposal to provide in the
rule itself that States would have the discretion to not include
emissions averaging in their implementation of the HON without having
to go through a section 112(l) rule approval process. One of the
commenters asserted that this proposal would circumvent the mandates of
State legislatures that had limited the ability of their environmental
agencies to enact requirements more stringent than Federal
requirements. The other commenter stated that this proposal was
unnecessary because the section 112(l) rule provides ample flexibility
and that the proposal would create difficulties for States since they
would have to choose whether or not to adopt averaging.
The EPA does not believe that either of these comments warrants
departing from the supplemental proposal regarding this issue. First,
by providing for State discretion to decide whether to implement the
HON with or without averaging, the EPA is not circumventing any State
laws or overriding the decisions of State legislatures that limit the
ability of State environmental agencies to adopt requirements more
stringent than Federal requirements. The EPA maintains that
implementing the rule with averaging will achieve equivalent or better
emissions reductions (in part due to the discounting provisions) than
implementing the rule without averaging. Consequently, in the EPA's
view, a decision to implement the rule without averaging would not be a
decision to implement a more stringent program. Moreover, if a State
law or constitution contained provisions that, in the State's view,
prevented the State from adopting the rule without averaging, nothing
in the rule would override that provision, i.e., in that situation, the
State agency would not have the authority to implement the rule without
averaging and the provision allowing the State to choose would not
change that. Second, the EPA does not agree that providing for State
discretion in the HON itself is either unnecessary or burdensome for
States. Use of a section 112(l) rule approval process would also permit
States to choose to implement the HON without averaging, providing for
that choice in the HON itself streamlines the process by eliminating
EPA review of the choice. In addition, since the section 112(l) rule
permits States to make the choice, providing for the exercise of such
discretion in the HON itself cannot be viewed as placing any new
burdens on the States. Finally, the EPA maintains that the provision of
an option will not impose a burden. The provision of an option
increases choice and flexibility; it does not impose new requirements.
c. Credit discount factors. A discount factor of 10 percent is
required in calculating credits for emissions averages in the final
rule. An exception is provided for reductions accomplished by the use
of pollution prevention measures. For pollution prevention measures,
full credit with no discounting is allowed.
At proposal, the EPA sought comment on whether it is appropriate to
require the use of a credit discount factor and what value between 0 to
20 percent should be selected for the discount factor. A number of
commenters supported the use of a discount factor, contending that if
the use of emissions averaging can enable sources to realize a cost
savings, the environment should benefit from that cost savings as well.
The EPA is persuaded that credit discounting is one way to provide such
a benefit to the environment. A discount factor would reduce the value
of credits in the emissions average by a certain percentage before the
credits are compared to the debits.
In considering a discount factor, the EPA examined the
requirements for determining MACT in section 112(d) of the Act. Section
112(d)(2) specifies that MACT standards shall require the maximum
degree of reduction in emissions of HAP's, taking into consideration,
among other things, the cost of achieving those reductions. By defining
the source broadly and including the option for emissions averaging in
the final rule, it could be argued that the EPA is providing
flexibility for source owners and operators that would lower the costs
of compliance. The EPA is persuaded that, to carry out the mandate of
section 112(d)(2), some portion of these cost savings should be shared
with the environment by requiring sources using averaging to achieve
more emission reductions than they would otherwise.
Several commenters opposed the idea of a discount factor for a
variety of reasons. Several warned that a discount factor would reduce
and could completely eliminate the incentive to use emissions averaging
and to develop innovative technologies which, in turn, could defeat the
EPA's efforts to encourage flexible compliance and innovation. However,
the EPA maintains that the discount factor is not large enough to
provide such a disincentive. The value is consistent with those used in
similar rules and programs. In addition, pollution prevention
innovations are specifically exempted, which is discussed in the next
paragraph. Other commenters viewed a discount factor as an
inappropriate penalty or price for achieving cost savings through
averaging, and some considered a discount factor to be inconsistent
with the statutory intent that MACT be implemented in a flexible and
cost-effective fashion. The EPA submits, however, that the emissions
averaging program as a whole provides ample flexibility and opportunity
for cost savings. Sources clearly have more flexibility to choose more
cost-effective means of compliance through averaging than without it. A
10 percent discount on credits does not negate this.
Credits generated through use of a pollution prevention measure
need not be discounted, because the EPA recognizes that encouraging
pollution prevention will result in more overall emission reductions,
possibly including multimedia reductions and lower overall releases
into the environment. For the purposes of the rule, the EPA is
referring to any pollution prevention activities described in the
Agency's Pollution Prevention Strategy (56 FR 7849) that are applicable
to this industry. The following activities are included in the
description of pollution prevention: (1) Substitution of feedstocks in
making a product that reduces HAP emissions; (2) alterations to the
production process to reduce the volume of materials released to the
environment; (3) equipment modifications; (4) housekeeping measures;
and (5) in-process recycling that returns waste materials directly to
production as raw materials. Other pollution prevention approaches that
are identified in the EPA's Pollution Prevention Strategy and are
applicable to this industry are also acceptable for credit.
4. Implementation and Enforcement
a. Compliance period. The EPA has decided to establish an annual
compliance period for emissions averaging. The rule was originally
proposed with an annual compliance period, and additional comment was
solicited in the supplemental notice on four alternative bases for
determining compliance:
(1) A quarterly block averaging period;
(2) A quarterly block averaging period with banking for up to one
or two additional quarters;
(3) A semiannual block averaging period with banking for an
additional six-month period; and
(4) A semiannual block averaging period.
Several commenters supported an annual compliance averaging period
at proposal and in response to the supplemental notice claiming: (1) It
is necessary to accommodate realistic operating scenarios in which
production rates naturally vary; (2) it is consistent with compliance
periods for programs promulgated under title I and title IV of the Act;
and (3) concerns about the enforceability of an annual period are
unwarranted. At the same time, several commenters criticized the
proposed annual period as: (1) Too long, especially compared to other
regulatory programs; (2) an administrative burden and thus, an obstacle
to effective enforcement; and (3) not protective of public health
because an annual compliance period could allow peak exposures for
short periods during the year.
Some commenters recommended the quarterly block averaging period
without banking as manageable, enforceable, and the best of the four
proposed options in the supplemental notice. A few commenters supported
quarterly averaging with banking. Other commenters supported semi-
annual averaging with banking as a period that would ensure operational
flexibility and reduce risk. No commenters recommended the semiannual
period without banking. Some commenters contended that the compliance
period should not be any longer than periods currently used in State
programs.
The final rule requires that the credits and debits generated in
emissions averages balance on an annual basis, and that debits do not
exceed credits by more than 30 percent in any one quarter of the year.
These two requirements are used together to establish an emissions
averaging system that provides flexibility for changes in production
over time without allowing for wide-ranging fluctuations in HAP
emissions over time. The annual compliance period was selected to
provide sources considerable latitude in selecting points for inclusion
in emissions averages. With an annual compliance period, sources can
average emission points that may not have the same emission rates
during some periods of the year, as long as they are similar on an
annual basis. This latitude will also be useful to accommodate averages
with points that must undergo temporary maintenance shutdowns at
different times during the year. Nevertheless, the annual compliance
period required here is solely meant to accommodate the specific
circumstances of the HON, and is not intended in any way as
establishing a precedent for future rulemakings.
In selecting a compliance period for averaging, the EPA also
considered the need to verify compliance and, when appropriate, take
enforcement action in a timely fashion. One concern about an annual
compliance period is that the EPA's authority to take administrative
enforcement actions would be significantly reduced because section
113(d) of the Act limits assessment of administrative penalties to
violations that occur no more than 12 months prior to the initiation of
the administrative proceeding. Administrative proceedings are far less
costly than judicial proceedings for both the EPA and the regulated
community. The requirement that debits not exceed credits by more than
30 percent in any quarter enables the EPA to use this administrative
enforcement authority by providing a shorter period in which to verify
compliance.
b. Quarterly emissions check. As noted previously, the final rule
also includes a quarterly emissions check whereby debits cannot exceed
credits by more than 30 percent. The emissions check was proposed as a
limit on the percent by which debits could exceed credits in a quarter.
Comment was requested on what the limit should be within a range of 25-
35 percent. The proposal preamble also presented another alternate
quarterly limit suggested by industry which would structure the check
as an absolute emissions limit.
Several commenters who supported an annual compliance period
concurred that a quarterly check was reasonable to allay concerns over
high emissions in short periods. However, several commenters opposed
the proposal contending that:
(1) Debits should never be allowed to exceed credits in any time
period;
(2) 25 to 35 percent is still not protective of health and welfare;
and
(3) It would be difficult for inspectors to determine whether or
not a facility is in compliance with its allowable emissions level.
The EPA did not adopt the suggestions of these commenters because
the emissions averaging program is intended to allow flexibility within
the quarterly and annual limits. This flexibility would be too severely
restricted if the suggestions, such as never allowing debits to exceed
credits, were adopted. The quarterly check will protect against
emission peaks so that health and welfare effects are avoided. The 30-
percent differential between debits and credits should not result in a
significant increase in emissions because only the emissions from the
few points in the average would increase. The EPA maintains that these
requirements are enforceable on a quarterly basis in that inspectors
will be able to total the credits and debits and determine if the
source is in compliance with the quarterly emissions checks and the
annual balance of credits and debits.
Some commenters supported the alternative industry proposal for a
quarterly check because: (1) It avoids situations where an emission
point is operated simply to generate needed credit; and (2) it allows
for easier, more flexible planning because the source would know what
its allowable emissions are for a fixed period. In contrast, one
commenter opposed the alternative proposal claiming that the allowable
emissions level would bear no relationship to the emissions level
sought to be achieved. The EPA maintains that a system of assigning
credits based on allowable emissions requires a great deal more
scrutiny of the source's prediction of operating levels. Operating
levels for allowable emissions are based on representative predictions
of realistic operating scenarios, and such a system creates an
incentive to ``game,'' i.e., to project higher utilization rates for
credit-generating points than is representative or realistic.
The EPA did not adopt the industry alternative for the quarterly
emissions check because of concerns about an absolute emissions limit
based on projections. However, the EPA did select the midpoint of the
proposed range of the quarterly check as a way of balancing industry's
concerns about operational flexibility with other commenters' concerns
about protection from peak emissions.
c. Banking. Credits cannot be banked for future use in emissions
averaging. Provisions for banking were included in the proposed rule,
and the EPA requested comment on whether or not allowing credit banking
was appropriate.
A number of commenters opposed allowing banking of emission credits
for several reasons, including:
(1) The requirement to achieve the maximum achievable emission
reductions is violated when banked credits are used to offset debits;
(2) Sources with banked credits will plan and operate less
carefully; and
(3) The use of banked credits will increase HAP exposures and
create administrative difficulties.
Several commenters supported allowing credit banking, claiming that
it would:
(1) Act as a safety valve for unexpected events and thus offer
needed flexibility to sources and increase the likelihood of a
successful averaging program; and
(2) Encourage sources to install more stringent controls earlier to
begin creating surplus credits to be banked.
Banking of surplus credits was deleted from the final rule
primarily due to the likelihood of significant administrative burden
resulting from its use. The EPA believes that administration of the
rule must be kept as simple as possible, and banking represented a
complication that would have affected sources and implementing agencies
alike. In addition, if banked credits were allowed to offset unexpected
increases in emission debits, peak HAP exposures could be more likely,
and in some years when banked credits would be used, sources could be
emitting beyond the standard. The additional flexibility afforded
sources through banking would have been offset by the increased
administrative burden and potential for peak exposures such that little
overall advantage could be gained from banking.
d. Credits for previous actions. Credit is not allowed in the final
rule for any previous actions, which, for the purposes of the rule, are
defined as any control actions taken prior to the passage of the 1990
Amendments to the Act on November 15, 1990. This is in contrast to the
proposal, which allowed three exceptions:
(1) Pollution prevention measures taken after 1987 and qualifying
under the EPA's Pollution Prevention Strategy; (2) 33/50 commitments;
or (3) Early Reductions commitments other than equipment shutdowns.
Control actions that meet the other requirements in the standard, and
that were taken after November 15, 1990, such as actions taken as
pollution prevention measures as part of the 33/50 program, can be used
to generate credits for an averaging program. However, as outlined in
the proposal, controls applied as part of an Early Reductions
commitment can generate credits only if they are more stringent than
HON requirements and only after the relevant point becomes subject to
the rule, that is, after the expiration of the 6-year extension for the
Early Reductions source.
Several commenters generally opposed allowing emissions averaging
credit for previous actions, and several specifically opposed the
proposal to allow the three exceptions. The commenters stated various
reasons for their opposition to allowing credits for previous actions
including:
(1) Participants in these programs had already derived sufficient
regulatory, economic, and public relations benefits so that additional
credit was unwarranted;
(2) Reductions under the 33/50 and Early Reductions Programs do not
constitute emission reductions under the HON;
(3) The EPA would be granting credit for emission reductions that
would have occurred anyway, possibly because of existing State or
Federal requirements, and thus, these credits would be only ``paper
credits,'' not new emission reductions; and
(4) Such credits violate the maximum achievable reductions
requirement.
On the other hand, a number of commenters argued that emissions
averaging credit should be allowed for all previous actions. The
commenters argued, for instance, that:
(1) Not allowing credit was unfair and penalized sources that
installed controls early and that early actions should be rewarded
instead; (2) it is a contradiction that a controlled emission point
that meets the requirements of the rule can be in compliance no matter
when it was controlled but is ineligible to generate credits for
emissions averaging; and (3) if credit is not allowed, control devices
already installed on Group 2 emission points will be removed and placed
on Group 1 points. Many of these commenters considered other prior
reductions to be appropriate as credit generators, such as: (1) any
voluntary control measures; and (2) any verifiable control measures.
The EPA agrees that emission reductions achieved prior to November
15, 1990 were accomplished for reasons unrelated to the Amendments or
the rule and thus constitute part of the baseline control of a source.
This rule does not allow actions taken before passage of the 1990
Amendments to be used to generate emission credits because such
reductions would have occurred anyway, for reasons unrelated to the
1990 Amendments or the proposed rule. If the EPA allowed these actions
to generate emission credits, then the source would be able to generate
more emission debits and, thus, more total emissions. Emissions
averaging is a method for complying with subpart G and should not
result in more emissions than the other compliance options.
With concern about the equivalency of emissions reductions from
averaging and non-averaging in mind, the Administrator also imposed the
limitation that controls applied to comply with a State or Federal rule
or statute (other than the HON) cannot be used to generate emissions
averaging credit. As with credits for controls applied before the HON
baseline date, credits for controls applied to comply with another rule
increase the source's ability to generate debits, but do not generate
new emission reductions, thus creating more total emissions. At the
suggestion of the public comment, the Administrator chose to disallow
HON averaging credit for controls applied to comply with other
requirements, thus ensuring that the source would not receive a
``windfall'' of credits. However, if an emission point has been used to
generate emissions averaging credit in an approved emissions average,
and the point is subsequently made subject to a State or Federal rule
other than this subpart, the point can continue to generate emissions
averaging credit for the purpose of complying with the previously
approved average. This provision does not constrain a State's ability
to establish any control requirements it believes are necessary for
purposes of attaining the national ambient air quality standards or to
reduce air toxic emissions. By including this provision in the final
rule, the Administrator has taken yet another step to ensure that
averaging provides equivalent or better air quality protection.
Although the three exceptions to the 1990 baseline that were
included in the proposal were deleted from the final rule, the EPA is
committed to the success of the 33/50 and Early Reductions Programs and
encourages the use of pollution prevention wherever feasible. This rule
does not diminish that commitment. Reductions achieved after November
15, 1990 under the 33/50 and Early Reductions Programs or by the use of
pollution prevention are fully creditable towards an averaging program.
e. Questionable monitoring. In the final rule, when an emission
point included in an average experiences an excursion, the presumption
is that a sufficient malfunction has occurred such that no credits or
maximum debits should be assigned to the point. As discussed in section
V.E.2.b, ``Excused Excursions,'' of this notice, an excursion occurs
when either: (1) There are insufficient monitoring data; or (2) the
operating parameter values are outside the permitted range. The final
rule provides that no credits and maximum debits will be assigned for
excursions because any other assumption would result in emission
reductions that could not be verified or adequately enforced. However,
if the source has data indicating that some partial credits or debits
may be warranted, it can submit that information to the implementing
agency with their next Periodic Report. Thus, partial credits and
debits can be assigned with the approval of the implementing agency.
The proposed rule did not contain these provisions, but comment was
requested in the supplemental notice on the advisability of including
these provisions.
A number of commenters supported the provisions to account for
excursions because: (1) They create an incentive for sources to
maintain and operate their monitoring equipment in good working order;
and (2) other methods for estimating emissions are inadequate and
should not be allowed as substitutes during these periods. On the other
hand, several commenters considered the provisions too extreme,
claiming that: (1) Even though excursions may occur, the control device
may not have failed completely; and (2) the compliance provisions for
points included in averages should not be more stringent than for the
ones that are not included.
The EPA maintains that these provisions are necessary to ensure
that averaging achieves equivalent reductions to point-by-point
compliance at all times. Emissions averaging depends on emissions
estimates made beforehand and the demonstration that debits and credits
balance made after the fact. Compliance on a point-by-point basis
requires only that the source demonstrate that the RCT was operated at
the proper design specifications. Hence, these provisions are not more
stringent; rather, they are more detailed to ensure the consistency of
the debit/credit estimation.
The EPA agrees that there may be some cases or conditions under
which the implementing agency can be satisfied that granting partial or
full credits and debits is still warranted. Therefore, the final rule
provides that the evaluation and issuance of credits and debits during
questionable periods shall be at the discretion of the implementing
agency.
f. Reference Control Efficiencies. The final rule does not allow
sources to get emissions averaging credit for the use of RCT above its
designated reference efficiency rating. In contrast, the proposed rule
provided two exceptions in which credit would be allowed for control
above rated efficiencies: (1) Storage vessels controlled with closed
vent systems and a 98-percent efficient control device, and (2) process
vents on which the source had demonstrated to the EPA that control can
achieve 99.9-percent reduction. These two exceptions have been deleted
in the final rule.
Several commenters supported allowing credit for the use of RCT at
a more efficient level than its rated efficiency as long as more
efficient control was demonstrable. Some commenters suggested that
credit for potentially significant reductions would otherwise be lost.
Other commenters warned that without such credit, sources would have no
incentive to develop existing control technologies further to achieve
greater efficiencies from RCT.
At the same time, some commenters supported not allowing credit for
RCT achieving higher efficiencies and opposed the two exceptions
included in the proposal. One commenter argued that allowing credit for
overcontrol is inappropriate because the rated efficiencies are
intentionally conservative and understate the actual reductions the RCT
would achieve if properly operated. As such, more credit would be
allowed for overcontrol than is warranted. Some commenters stated that
the use of fixed reference control efficiencies simplifies the
averaging process by applying uniform credits and debits.
Reference control efficiency ratings for RCT were established
because each RCT has a minimum level of emissions reduction that can
generally be achieved. The EPA acknowledges that RCT can sometimes
achieve greater emission reductions. However, providing credits for
these instances is inappropriate because the magnitude of debits, not
just credits, is based on the RCT's reference efficiency ratings. If it
could be determined that the RCT on a debit generator could achieve
greater reductions than its rated efficiency, the magnitude of debits
from the point would be greater. Thus, to give credit for reductions
above an RCT's rated efficiency and not to increase the magnitude of
debits as well would represent a windfall from averaging.
g. Approval of New Devices. The procedures that were proposed for
approving new devices for compliance purposes or as reference control
technologies have been maintained in the final rule without change.
Some commenters requested more guidance from the EPA on the process
for approving innovative control technologies. Others were concerned
with the time required to approve new technologies, including the time
required to review for broader applicability.
The EPA considers it necessary to be deliberate in approving new
technologies especially when proven reference control technologies are
available. The design and operation of new technologies are certain to
be unfamiliar, so the rule provides for a 120-day period for the EPA or
the permitting authority to determine whether sufficient information to
determine a nominal efficiency has been submitted. Then, the EPA or the
permitting authority must decide within an additional 120 days after
sufficient information has been submitted whether to approve a new
technology and what nominal efficiency to assign.
Moreover, review of a new technology for broad applicability does
not require any additional time beyond the time required for review and
approval of the new technology. Where the EPA is responsible for
approval, the approval and the review for broad applicability are one
and the same. Where the permitting authority is responsible for
approval, the rule provides that any further EPA review for broader
applicability shall not delay the permitting authority's approval of
the new technology for use in limited circumstances.
E. Compliance, Recordkeeping, and Reporting
1. General Burden
In the final rule, every effort has been made to reduce the
recordkeeping and reporting burden of the HON. The EPA has streamlined
the rule to include only the monitoring, recordkeeping, and reporting
necessary to ensure compliance.
Many commenters stated that the proposed monitoring, recordkeeping,
and reporting requirements of the HON would be excessive and
burdensome. The commenters contended that the requirements would be
very costly, are unnecessary for assessing a source's compliance
status, and provide no environmental benefit.
The single most significant change made to reduce the burden is
requiring retention of hourly average values of monitored parameters
instead of 15-minute values. This change reduces by a factor of four
the number of records that must be digitally converted by computer
systems, copied onto tapes or printed as hard copy, duplicated, and
stored.
There are a number of other areas where the burden has been reduced
in the final rule. For instance, the transfer operation provisions were
revised to no longer require 5-minute records and to allow design
analyses instead of performance testing for racks that are used
infrequently (see section V.G.3.b of this notice, ``Transfer
Operations--Testing and Monitoring'').
Equipment leaks recordkeeping and reporting requirements have been
reduced by streamlining the reporting system so there are two reports
per year, which can be submitted at the same time as the subpart G
reports. To reduce the leak detection burden, response factor
adjustments to Method 21 results are not required in the final rule.
The requirements to identify and document equipment not in VOHAP
service and equipment in vacuum service have been deleted. (The
rationale for these equipment leaks changes is contained in section
VI.D and E of this notice.)
Wastewater operations monitoring, recordkeeping, and reporting
requirements have also been reduced. Method 21 is now only required
initially, instead of annually as proposed, and visual inspections are
performed on a semi-annual basis. Monthly measurements required in
table 11 of the proposed subpart G were deleted because the initial
performance test is sufficient to determine compliance. A change to the
location of point of generation sampling will reduce the testing,
monitoring, reporting, and recordkeeping requirements for some sources
because sampling may be done at fewer locations. The compliance
requirements for maintenance wastewater and maintenance turnaround
wastewater have been combined, which simplifies compliance and
reporting. Very small containers (less than 0.1 m\3\ capacity) are no
longer subject to the rule, reducing the monitoring and recordkeeping
burden. These and other changes to the wastewater provisions are
discussed in sections V.C.3 and V.G.4 of this notice and in BID volume
2B.
In addition, the final rule allows sources to request approval to
use alternative monitoring and recordkeeping systems (in addition to
being able to request approval to monitor alternative parameters as
allowed in the proposed rule). This will reduce the burden by allowing
greater use of existing systems. Alternative monitoring systems
specifically discussed in the rule include non-automated systems and
data compression systems. These systems will be allowed on a site-
specific basis, dependent upon approval of the permit authority, as
described in section V.E.2.c of this preamble.
Some repetitive reporting has been eliminated. For example, new
sources that submit an application for approval of construction do not
need to submit an Initial Notification. Electronic submission of
reports is also allowed, if acceptable to the permit authority.
For further discussion, see chapters 2 and 3 of BID volume 2E and
the following sections of this preamble.
2. Monitoring and Relationship to Compliance
a. Continuous parameter monitoring and compliance determination.
The final subpart G provisions, as did the proposed provisions, require
monitoring of control device operating parameters and reporting of
periods when parameter values are outside the site-specific ranges the
source established in its operating permit or Notification of
Compliance Status.
Some commenters agreed with the HON approach to establish site-
specific parameter ranges to indicate proper operating conditions, but
many industry commenters asserted that parameter values outside the
established range should not be considered a violation of the
requirements for proper operation. These commenters requested the
removal of provisions stating that parameter range excursions indicate
the operator has failed to properly operate the control device.
Several of these commenters requested that sources be able to
demonstrate, through performance testing, that no violation of the
emission standard has occurred. Several commenters stated that a direct
correlation between the monitored parameter values and efficiency of
the control device has not been established. Some environmental
organizations and private citizens requested monitoring of the actual
emission levels instead of monitoring whether the control equipment is
operating properly.
Several commenters discussed the difficulty of knowing whether an
emission limit has been exceeded using parameter monitoring because
excursions are initially violations of a permit condition and not a
violation of an emission standard. The commenters were also concerned
that emission standards may be difficult to enforce using this system.
Several commenters requested clarification of the interaction of
the Title VII Enhanced Monitoring program and HON and asked whether
enhanced monitoring has been incorporated in the HON rule.
The part 64 enhanced monitoring rule does not apply to sources
subject to 40 CFR part 63, and therefore does not apply to sources
subject to the HON. However, rules developed under section 112 of the
Clean Air Act will include monitoring strategies that incorporate the
concepts of enhanced monitoring established in section 114(a)(3) of the
Act. This approach is designed to ensure that monitoring procedures
developed for section 112 standards provide data that can be used as a
determinant of compliance with each applicable standard, including
emission standards.
For rules where CEM's are not technologically or economically
feasible, the EPA will generally establish operating parameters which
must be continuously monitored to determine a source's compliance
status. In order to determine compliance, parameters must be monitored
frequently enough to allow the source owner or operator to certify
whether compliance was continuous or intermittent for each
recordkeeping period associated with the applicable emission limitation
or standard. Generally, the EPA will select the parameters that must be
monitored; however, the sources will establish, through performance
tests, engineering analysis, and manufacturer's recommendations, the
levels which must be maintained in order to remain in compliance with
the emission standard. These source-specific levels will be
incorporated in a source's operating permit (or, in the absence of an
operating permit, these established levels will be directly
enforceable) and will be used to determine a source's compliance
status. For future section 112 standards, deviations from the operating
parameters are expected to be considered violations of the applicable
emission standard.
However, in developing an operating parameter monitoring strategy
for the HON, it became evident that the complexity of this particular
standard, the wide range of processes and pollutants covered, and the
potentially large numbers of emission points located at any one
facility, would warrant a somewhat different approach in determining
compliance based on monitored parameters. Specifically, when a daily
average value of a monitored parameter is outside the established
range, such an excursion would not be considered a violation of the
emission standard, but rather, a violation of proper operating
conditions. Further, the HON allows for a designated number of excused
excursions, i.e., a predetermined number of average daily parameter
values outside the source's established range, that would not
constitute an operating parameter violation.
This variation to the Agency's standard approach of incorporating
enhanced monitoring concepts into section 112 rules does not signal a
change in underlying Agency policy, nor should it be viewed as a
precedent for future standards developed under 40 CFR part 63. Rather,
the method of compliance determination in the HON represents an
exception to the normal enhanced monitoring requirements, and one that
is deemed necessary because of the diversity of emission points and the
unique nature of the facilities regulated under this standard. The EPA
believes that for other MACT standards which will regulate a more
narrow range of industrial sources, a more precise link between
operating requirements and emission violations will be justified.
Many commenters requested that CEM's be included in the rule for
use in monitoring HAP emission levels, instead of using continuous
parameter monitoring.
The EPA considered CEM's for use in the HON, but found them to be
technically infeasible due to the lack of CEM technology for all 112
HAP's regulated by the HON. This determination is discussed further in
section 3.2.4 of BID volume 2E.
b. Excused excursions. The final provisions allow a maximum of six
excused excursions for the first semiannual reporting period,
decreasing by one excursion each semiannual reporting period, down to
one excused excursion per period by the end of 3 years. Thereafter,
sources are allowed one excused excursion per semiannual reporting
period. Excused excursions are not considered violations.
The EPA requested comment in the proposal preamble on the number of
days or percent of operating time that should be allowed as excused
excursions, and whether the excused number of days should decrease over
time. A range of 3 to 6 days was proposed.
Commenters supported a range of 0 to 6 days of excused excursions.
A number of commenters stated that the excused excursions were
necessary to account for inevitable and unanticipated operating
parameter fluctuations.
The system of decreasing the number of excused excursions as the
source becomes more familiar with the operation of their control device
allows sources to benefit from the knowledge they gain over time.
The final rule states, as at proposal, that a malfunction that is
included in the source's start-up, shutdown, and malfunction plan,
required in Sec. 63.6(e)(3) of the General Provisions, is not
considered an excursion if the plan is followed. If the plan is not
followed, or if the malfunction is not included in the plan, this is
considered an excursion.
For the final rule, an excursion has occurred when the source's
daily average falls outside the established ranges, or when monitoring
data are insufficient to calculate valid hourly averages for at least
75 percent of the operating hours in a day. Monitoring data are
insufficient to calculate a valid hourly average if measured values are
unavailable for any of the 15-minute periods within the hour. If the
excursion is not an excused excursion, it is a violation of the
operating permit conditions (i.e., a violation of proper operation and
maintenance of the control device). Each excursion is a direct
violation of the operating conditions, but not the emission limit. As a
violation of the operating conditions, the regulatory authority can
take enforcement actions against the source. If the regulatory
authority requests a performance test to determine compliance with the
emission limit, and the test reveals the emission limit is exceeded,
then the source has violated the emission limit and is subject to
enforcement actions for violating the emission standard.
c. Alternative monitoring and recordkeeping. The proposed
provisions allowing sources to request approval to monitor alternative
parameters were retained in the final provisions and expanded to allow
sources to request approval to use alternative monitoring and
recordkeeping systems. These monitoring systems would be approved by
the permit authority on a case-by-case basis, and would include
requests to use non-automated monitoring and recording systems and data
compression systems.
Many commenters requested that the rule allow the utilization of
existing monitoring and recordkeeping equipment to the maximum extent
possible, and discussed the need for these alternative monitoring and
recordkeeping systems. A few commenters requested that sources that do
not have automated monitoring and recording systems be allowed to
continue to use manual recording systems and be granted a less frequent
monitoring schedule.
The EPA expects that there will be few facilities that would choose
not to use automated recording systems (e.g., strip charts or computer
systems) in light of the labor costs of manual recordkeeping. However,
there may be specific cases where use of a manual system would be less
burdensome, for example, a smaller, older facility that does not have
computerized recording and already has a manual monitoring and
recordkeeping system. Provisions were added to the final rule to allow
sources with non-automated systems to request approval from the
permitting authority to manually read the value of the relevant
operating parameter less frequently than every 15 minutes. The rule
provides specific criteria for such requests to ensure that the
monitoring and recordkeeping system is sufficient to determine
compliance. In particular, the system shall include manual reading and
recording of operating parameter values no less frequently than once
per hour and daily average values calculated from the hourly values.
The request shall contain a description of the monitoring and
recordkeeping system, documentation that the source does not have an
automated system, reasons the source is requesting an alternative
system, and demonstration that the monitoring frequency is sufficient
to represent control device operating conditions. Approval of such
systems will be decided on a case-by-case basis by the permit
authority.
Many commenters requested that data compression be allowed in order
to allow use of current systems, while still allowing determination of
when exceedances have occurred. Data compression systems do not record
monitored operating parameter values at a set frequency, but record all
values that meet set criteria for variation from previously recorded
values. The commenters stated that they currently used data compression
systems or intended to install such systems, and that the advantages of
data compression include the ability to more accurately represent
operating parameter variation, the ease of data retrieval from archived
data, reduced data storage requirements resulting in reduced computer
costs, automatic record generation, the ability to quickly detect
operating problems, and access past data and predict future problems.
The commenters provided technical information on data compression
systems.
After considering technical information on data compression
systems, the EPA concluded that properly designed data compression
systems can provide sufficient information for determining compliance.
The final rule allows a source to request approval from the permitting
authority to use data compression as an alternative monitoring and
recordkeeping system. The EPA has established minimum criteria for
using data compression, including: Measuring the operating parameter
value at least once every 15 minutes; recording at least four
representative values each hour; recording the date and time when
monitors are turned off and on; recognizing unchanging data, alerting
the operator, and recording the incident; and computing daily averages
from the recorded data. At the end of the operating day, if the daily
average value is not an excursion, the data may be converted to hourly
averages instead of retaining the four individual data values for each
hour. Approval of such systems will be decided on a case-by-case basis.
Some commenters requested that sources be allowed to use interlock
devices which monitor the control device operating parameters and shut
down the process before an excursion can occur. The commenters
suggested that if such systems are used, recordkeeping is not
necessary.
While the EPA wishes to encourage innovative technologies such as
interlock systems, the EPA has insufficient information on the variety
of designs and applications of interlock systems to specify alternative
recordkeeping procedures that would be appropriate for all such
systems. Sources wishing to use other alternative monitoring methods,
including sources using interlock devices, may apply to do so according
to the process described in the General Provisions Sec. 63.8(f).
d. Inspections and non-continuous monitoring. For some emission
points, such as storage vessels and some wastewater operations,
continuous parameter monitoring is not feasible in certain
circumstances due to the design of the control device or other
operational and system design characteristics of the emission points or
control technologies. One example of non-continuous monitoring is the
periodic visual inspection of storage vessels equipped with internal or
external floating roofs. If a failure, such as a gap or tear in the
seal, is detected, the vessel must be repaired or emptied within 45
days. In addition, two 30-day extensions may be requested from the
Administrator. Violations occur only when a failure is detected and the
vessel is not repaired or emptied within 45 days or the time provided
with an extension. More information on inspections and non-continuous
monitoring is provided in chapter 6 of BID volume 2B for wastewater
operations and chapter 3 of BID volume 2A for storage vessels.
3. Records
a. Continuous records. The final rule allows retention of hourly
average values of monitored parameters instead of 15-minute values for
operating days when there is not an excursion. If there is a monitoring
parameter excursion, the 15-minute values for the excursion period must
be retained.
A number of commenters requested that only hourly or daily averages
be required, as 15-minute values would require reprogramming their
computer systems and would be costly. The commenters also contend that
15-minute values may not be necessary to demonstrate compliance with
the rule because operational problems would occur over a period of
several hours, and could be discovered through the hourly averages.
Some commenters suggested that 15-minute records should only be kept
for days when there are parameter excursions.
The EPA agrees with the commenters who suggested that hourly
average values are generally sufficient to determine compliance, and
that 15-minute records should be kept only if there is an excursion. As
at proposal, compliance with the operating conditions is based on the
daily average value of continuously monitored parameters. If the daily
average value is outside the established range, this is an
``excursion.'' The proposal required retention of 15-minute average
data values to substantiate the daily average calculations and provide
a record of trends in control device operation over a shorter time
period. Records of hourly average values are sufficient to accomplish
these purposes, and will greatly reduce the recordkeeping burden of the
HON. This change will reduce by a factor of four the number of records
that must be digitally converted by computer systems, copied onto tapes
and/or printed as hard copy, duplicated, and stored. It will avoid the
cost of reprogramming existing computerized recordkeeping systems that
commenters said are currently programmed to retain hourly averages. The
reduction in the number of records will also simplify review of these
records by enforcement agencies.
The reduction in the number of records will not impair the ability
to detect parameter excursions. The final rule requires continuous
monitors to measure parameter values at least once every 15 minutes, as
did the proposal, and many monitors are designed to measure more
frequently. The final rule also requires recording of 15-minute average
values or instantaneous readings taken at least once every 15 minutes.
However, the final rule allows the 15-minute values to be converted to
hourly average values at the end of the operating day if there was not
an excursion. The 15-minute values can then be discarded, and only the
hourly averages must be retained. For operating days when there is an
excursion, the final rule requires retention of the 15-minute values of
parameters. This will provide a more detailed record of those periods
when there are problems. Keeping 15-minute instead of hourly values for
excursion periods will not significantly increase the recordkeeping
burden because there should only be a couple of days per year when
there are parameter excursions for any given emission point.
A few commenters stated that the requirement in the transfer
operations provisions to take 5 [and 15] minute values was incompatible
with their current data collection system, would be extremely costly,
burdensome, and of no environmental benefit.
The transfer provisions have been revised for the final rule and no
longer require retention of 5-minute and 15-minute records. Hourly
records (and 15-minute records for excursions) are required for
transfer as well as the other kinds of emission points. Transfer is
discussed in more detail in section V.G.3.b and in the BID.
b. Accessibility/storage. A number of commenters requested that
sources have the option of storing records at an accessible off-site
location because retaining records on-site at a source for 5 years
would be burdensome and expensive.
This is an issue addressed in the notice presenting the final
General Provisions to part 63. The provisions of subpart F are
consistent with the final General Provisions. For the first 2 years,
records may be retained on-site or at a central location accessible by
computer. For the following 3 years, records may be maintained at an
off-site location.
c. Retention time. Several commenters maintained that retaining
records for 5 years as required in the proposal would be burdensome and
expensive. Instead, commenters suggested records be retained for 1 or 2
years.
The final rule requires retention of records for 5 years. This is
consistent with the General Provisions and the operating permits rule.
This issue is addressed in the notice presenting the final General
Provisions to part 63. The Agency's rationale is contained in the
preamble to the final General Provisions.
4. Compliance Schedule
a. Group status changes. The final rule establishes compliance
dates for cases in which a Group 2 emission point becomes a Group 1
emission point. The final provisions differ from the proposed
provisions.
Several commenters requested that a Group 2 emission point that
becomes a Group 1 emission point be granted 3 years to come into
compliance, as existing sources are allowed 3 years, and the proposed
150-day period may not be possible given the time needed for permitting
and installation of controls.
The EPA decided that, in some cases, the proposed 150 days may not
be sufficient to engineer, permit, purchase, and construct control
equipment to comply with the requirements; whereas, in other cases,
compliance could be achieved sooner. Therefore, the proposed 150 day
period was deleted from the rule, and compliance date provisions were
added to Sec. 63.100 of subpart F. In certain cases specified in
subpart F, the source is allowed to establish a site-specific schedule
subject to the approval of their permit authority. To be consistent
with section 112 of the Act, the schedule can be no longer than 3
years. The reader should refer to Sec. 63.100 of subpart F to determine
whether a site-specific schedule is allowed in a particular case.
b. Compliance extensions. The final rule, like the proposed rule,
states that requests for extensions must be submitted as part of the
operating permit application or as part of the Initial Notification or
as a separate submittal no later than the date the Implementation Plan
is due. In the preamble to the proposed HON rule, the EPA requested
comment on the potential difficulties of complying with the HON in the
3-year compliance time and through use of the 1-year request for a
compliance extension.
Many commenters stated that it would be difficult or impossible for
some sources to meet the HON's 3-year compliance date due to both
obvious and unforeseen circumstances and that the need for a compliance
extension may not be recognized until after the Implementation Plan is
due. The sources requested that they be allowed to apply for a
compliance extension up until the compliance date.
The issue of whether compliance extensions can be requested up
until the compliance date is an issue with broad applicability to all
part 63 standards and was raised in the public comments on the General
Provisions to part 63. The HON is consistent with the final General
Provisions.
5. Other Comments
Many other comments were received on topics such as the five report
system, electronic submittal of reports, recordkeeping and reporting
consistency with other requirements, burden cost estimates, data
collection and recording frequency, current use of automated and non-
automated monitoring systems, record retention time and accessibility,
impacts on regulatory agencies, site-specific ranges, performance
testing, enforcement, and many other topics. A complete summary of the
comments received and the EPA responses pertaining to monitoring,
recordkeeping, reporting, and compliance may be found in chapters 2 and
3 of BID volume 2E. Comments and requirements pertaining to emissions
averaging monitoring, recordkeeping, and reporting issues are discussed
in section V.D of this notice and in section 2.8.2 of BID volume 2C.
F. Coordination with Other Clean Air Act Requirements
1. General Provisions
After proposal of the General Provisions (August 11, 1993; 58 FR
42760), the HON public comment period was reopened to take comment on
several issues, one of which was the overlap between the HON and the
General Provisions. Written comments were received from approximately
75 commenters. Many of these commenters contended that it was difficult
to determine those instances when the General Provisions requirements
apply to the HON. The commenters suggested that the HON specifically
state those General Provisions sections that apply to the HON, instead
of the current system which states which General Provisions sections do
not apply. The commenters, some of whom also included the comments they
had submitted to the General Provisions docket, provided tables and
suggested text changes showing which specific General Provisions
sections they thought were relevant to the HON, and which General
Provisions sections they thought should not apply to HON sources. In
response to these comments, the EPA has provided a table in subpart F
of the rule which specifies which General Provisions sections do and do
not apply to the HON.
2. Overlap with NSPS, NESHAP, and CTG
For the final rule, the EPA has clarified which requirements are to
be met when an emission point is subject to other air regulations in
addition to the HON. The EPA agreed with commenters that the proposed
rule did not provide adequate guidance regarding what to do when the
HON overlaps with other NESHAP and NSPS.
Several commenters contended that the proposed HON would lead to
overlap with existing regulations, and because EPA did not provide
details on which requirements are to be met when such situations occur,
the overlap between the HON and other regulations would lead to
confusion, inconsistent application of the requirements, and possible
compliance violations. The commenters claimed that the EPA's direction
to comply with the most stringent regulation was inadequate. Several
commenters specifically questioned whether the language on overlapping
requirements was intended for all facets of the HON or only for
recordkeeping and reporting, since the requirement appeared in the
recordkeeping and reporting section of subpart F.
A number of commenters specifically stated that sources complying
with the Benzene NESHAP or the Vinyl Chloride NESHAP should be exempt
from complying with the HON because these standards are more stringent
than the HON. A few commenters expressed concern that the wastewater
provisions in the HON may conflict with the requirements of the Benzene
NESHAP, particularly the use of biological oxidation units.
The EPA recognizes that the guidance in the proposed HON on
determining which requirements to comply with when regulations overlap
was confusing. In order to clarify these requirements, the EPA has
listed in Sec. 63.110 of the final rule which provisions owners or
operators are required to comply with when they are subject to existing
regulations.
The EPA believes that in most cases the HON contains more stringent
requirements than in other existing regulations. For these cases, the
EPA has decided to override the requirements of the existing
regulations with the requirements of the HON. In other cases, the owner
or operator must either comply with the HON and the overlapping
regulation, with the overlapping regulation, or some combination of the
two.
For most Group 1 emission points that are also subject to existing
NSPS and NESHAP, the owner or operator is required to comply with the
HON requirements. For wastewater, Group 1 and Group 2 streams must
either comply with both the HON and the Vinyl Chloride NESHAP or submit
a demonstration that compliance with the Vinyl Chloride NESHAP assures
compliance with the HON. Group 1 and Group 2 wastewater streams subject
to both the HON and the Benzene NESHAP must comply with both rules
because it is not possible for one rule to override the other. The
benzene rule cannot override the HON because the HON covers 112 organic
HAP's whereas the benzene waste operations NESHAP only covers emissions
of benzene. The EPA does not believe that in all cases demonstration of
control of benzene will also demonstrate compliance with control
requirements for all HAP's. The HON cannot override the benzene rule
because the benzene rule applies to waste and wastewater and the HON
only applies to wastewater. Thus, in the final HON, the EPA is
requiring that a source subject to both rules must comply with both
rules.
For Group 2 emission points that are also subject to existing NSPS
and NESHAP, Sec. 63.110 specifies which provisions of HON and which
provisions of the other rules will apply. The EPA developed the
specifications through a comparison of the rules and their monitoring,
recordkeeping, and reporting requirements for each kind of emission
point. When HON wastewater provisions overlap with RCRA regulations,
the EPA has decided to allow owners or operators to either comply with
the regulation they consider the most stringent, or to request a case-
by-case determination by the Administrator of which requirements to
comply with.
A few commenters expressed concern that if future MACT standards
require more stringent control, facilities would have to replace
technology required by one standard with that required by another.
The EPA's plan for implementing the Act is for each source category
to have its own MACT standard. No two MACT standards should be
applicable to the same emission point. The only future requirements
that should apply to the emission points subject to the HON are those
developed during the residual risk analysis for the HON. The EPA has
done its best to clarify the applicability of the HON. However, it is
difficult to anticipate all the potential overlaps with MACT standards
that have not yet been drafted. In developing the applicability
provisions of future MACT standards, the EPA will be as clear as
possible and will avoid applying more than one MACT standard to the
same emission point.
3. PSD/NSR
For the final rule, the EPA maintains that the approach for
estimating secondary impacts that was presented in the proposed HON is
sufficient for rulemaking purposes.
Several commenters argued that compliance with the RCT requirements
of the HON would increase NOx and CO emissions, thereby requiring
PSD or NSR determination depending on non- attainment status of the
source. The commenters also contended that PSD and NSR determination
would require a BACT or LAER analysis, air emissions modeling, offsets
for NOx emission increases, and possibly a Federal Land Manager
review. Several of the commenters claimed that the cost of these
analyses and the control technologies they may require were not
included in the cost analysis for the HON. The commenters contended
that such costs would make compliance with the HON unaffordable.
The commenters are correct that costs for controlling secondary
impacts were not analyzed in the HON. However, the EPA did analyze the
extent of multimedia impacts of applying the RCT's. The results of the
analysis indicated that controls on process vents would result in only
6 percent of the sources exceeding the PSD NOx threshold of 40 tpy
in non-attainment areas if combustion controls were applied, and none
of the sources would exceed the CO emissions threshold of 100 tpy. None
of the sources were determined to exceed the CO and NOx emission
levels as a result of controlling transfer operations. Based on these
results and the great flexibility provided in compliance options, the
EPA does not consider that control of secondary impacts of applying the
RCT's will significantly impact the cost of the HON.
In addition, although the HON provisions for process vents and
transfer operations require 98-percent control, they do not necessarily
require combustion. A facility has the choice of applying the RCT or
using any technology that achieves an equivalent emissions reduction.
The process vents provisions also provide the option of modifying the
process or using additional product recovery to raise the TRE to
greater than 1.0, thereby converting the vent to a Group 2 vent.
Other commenters argued that the permit review process for PSD and
NSR would increase the amount of time for complying with the HON, and
cause some sources to miss compliance dates.
The EPA considers PSD and NSR concerns to be best handled on a
site-specific basis. An individual source may cite the delays involved
with obtaining PSD or NSR permits in requesting extensions from the
EPA. Under the Pollution Control Project exclusion section of the NSR
regulations, States will also have the flexibility to consider overall
environmental benefits of pollution control and may not require a
source to obtain preconstruction permits under PSD or NSR.
Several commenters requested that EPA exclude from the definition
of modification, and thus from NSR requirements, the installation of
controls required in the HON that are considered environmentally
beneficial.
The EPA is reviewing possible changes to the NSR/PSD program. Until
such changes are made, the EPA has decided that sources requesting
exemptions will be handled on a case-by-case basis. Where a source
merits it, the EPA will consider exclusions from some NSR/PSD
requirements.
4. Section 112(g)
Several commenters requested that the EPA clarify the relationship
between the HON and requirements in section 112(g) of the Act. Some
commenters requested that EPA provide definitions for modification and
reconstruction as they apply to the HON. One commenter requested that
the EPA incorporate a de minimis emissions increase concept for minor
modifications.
Case-by-case MACT emission limitations under the proposed section
112(g) rule do not apply to SOCMI sources covered by today's rule. The
EPA need not add a de minimis emissions increase concept for the HON
because the HON has established procedures for determining which
operational changes require control and what level of control must be
applied when an operational change occurs. In addition, since section
112(a) of the Act provides a definition for modification and Sec. 63.2
of the General Provisions (subpart A of 40 CFR part 63) provides a
definition for reconstruction, these definitions need not be added to
the HON. Sources subject to the HON are required to use the definitions
in the Act and General Provisions, unless that part of the General
Provisions is specifically overridden in the HON.
Sources subject to the HON should note that subparts F and G
establish administrative procedures to cover a variety of operational
changes that are likely to occur at SOCMI facilities. These procedures
specify the notification and approval requirements for each type of
change. As stated in the preamble to the proposed rule implementing
section 112(j) of the Act, it is the EPA's intent that the control
requirements of individual MACT standards established under section
112(d) or 112(j) of the Act should supersede the control requirements
of the section 112(g) rule. The proposed rule for section 112(j) was
published in the Federal Register at 58 FR 37777 (July 13, 1993). In
addition, as stated in the proposed rule implementing section 112(g) of
the Act, it is the EPA's intent that the administrative procedures of
individual MACT standards established under section 112(d) or the Act
will supersede the administrative procedures of the section 112(g) rule
to the extent that the administrative procedures of a section 112(d)
rule satisfy the requirements of section 112(g) of the Act. [As
proposed (58 FR 37778), standards established under section 112(j) of
the Act would rely on the administrative procedures in the section
112(g) rule.] The question of whether MACT standard administrative
procedures, such as those in the HON, supersede the administrative
procedures of the section 112(g) rule is one on which comment is being
requested in the section 112(g) rulemaking. Consequently, the
application of section 112(g) administrative procedures to HON sources
will not be finally resolved until the promulgation of the section
112(g) rule. Until final action on the section 112(g) rule, sources
subject to the HON should follow the administrative procedures in
subparts F and G, and, as appropriate, the General Provisions of 40 CFR
part 63 subpart A, and the title V operating permits rule.
One commenter requested that the EPA clarify whether emission
points that are not regulated by the HON, but are part of the same
plant site, would be considered area sources and what emissions would
be available for offsets under section 112(g).
The Act defines both major source and area source. If a plant site
meets the definition of major source, it will be regulated as a major
source under any applicable MACT standard. Plant sites that do not meet
the definition of major source are considered area sources and could be
covered under emission standards that regulate area sources. For
example, if within a petroleum refinery that is a major source plant
site, there are emission points associated with SOCMI processes, the
SOCMI emission points would be regulated under the HON, whether or not
they alone would constitute a major source. The refinery emission
points would be regulated under the refinery MACT standard. The rule
implementing case-by-case MACT emission limitations under section
112(g) will address sources that are not covered by a promulgated MACT
standard. Only emission points that are not subject to a promulgated
MACT standard could be available for offsets. If a source is regulated
by a promulgated MACT standard such as the HON, the controls applied to
comply with the promulgated MACT will not be available for offsets
under section 112(g), as proposed. At plant sites with sources subject
to the equipment leak provisions in subparts I and H, only the
equipment leaks are covered by the HON. Thus, the section 112(g)
control requirements could apply to the other actions and equipment at
the plant site.
5. Residual Risk
A number of commenters expressed concern with calculating residual
risk on a plant-wide basis because once a MACT standard is promulgated
for one source category within a facility, residual risk requirements
could be triggered before other MACT standards are established for
other source categories at the facility. In contrast, one commenter
asserted that the legislative history of the Act requires that residual
risk be calculated on a plant-wide basis.
A number of other commenters expressed concerns with calculating
residual risk on a source category basis because public health could be
compromised if emissions were artificially split up for purposes of
risk assessment, rather than considered as a whole. However, two
commenters contended that implementation would be simplified if a
source category approach were taken.
Several other commenters argued that the basis for estimating
residual risk should not be addressed in the HON or at this time. The
commenters contended that Congress intended to defer risk-based
standards until better methods of risk analysis have been defined. Some
commenters requested that the EPA begin to investigate the appropriate
methodology for determining residual risk.
As many of the commenters have noted, residual risk will be
determined at a later time. The EPA's intent in requesting comments on
residual risk was to facilitate ideas on how residual risk should be
analyzed.
6. RCRA and OW Regulations
Several commenters asserted that the HON did not consider overlaps
with RCRA rules. The EPA disagrees with the commenter's assertion that
the EPA has not considered the implications associated with regulatory
overlap between the HON and the RCRA regulations. In fact, the EPA has
made every effort to identify areas in which these regulatory programs
may overlap. The commenter did not express any particular concerns
about specific areas of overlap. The EPA has identified several
potential areas in which both the RCRA and the HON could apply to the
same situation. To avoid dually regulating these areas, the EPA has
tried to make the regulatory language in the HON consistent with
existing RCRA requirements and, where appropriate, has designated which
regulations the owner or operator must comply with to satisfy the
requirements of both regulatory programs. For example, in the
provisions that specify the required treatment processes for managing
wastewater at SOCMI sources, the EPA will accept demonstration of
compliance with RCRA requirements as demonstration of compliance with
the HON for the following treatment processes: (1) hazardous waste
incinerator permitted under 40 CFR part 270; (2) boilers and industrial
furnaces either permitted under 40 CFR part 270 or certified as an
interim status facility in compliance with 40 CFR part 266; and (3)
underground injection wells permitted under 40 CFR part 207 and in
compliance with 40 CFR part 122. These treatment processes are not
subject to the treatment process requirements in the HON because the
EPA recognizes that such treatment processes are already strictly
regulated under the RCRA program. However, emissions from the
wastewater stream must still be suppressed up to these treatment
processes according to Secs. 63.133 through 63.137 of the HON.
7. Pollution Prevention
For the final rule, the EPA maintains that the proposed HON
sufficiently promotes pollution prevention for the various chemical
manufacturing process units in the SOCMI.
One commenter did not consider the HON to meet the requirements of
the Act because it does not consider pollution prevention activities.
Several other commenters contended that the HON discourages pollution
prevention activities because it promotes use of pollution controls and
safety measures instead of redesign of processes or material
substitutions to eliminate emissions. Some of the commenters believed
that industry will innovate and apply pollution prevention only if EPA
forces them to do so. Many of the commenters recommended that the EPA
revise the HON to encourage more pollution prevention. The commenters
suggested that EPA:
(1) Incorporate pollution prevention approaches in existing State
programs;
(2) Set a timetable for the elimination of emissions; and
(3) Require evaluation of process and product changes prior to end-
of-pipe controls.
Pollution prevention activities, particularly process redesign, are
site-specific. Therefore, it would not be practical or possible to
stipulate specific requirements for the large number of chemical
production processes subject to the HON.
The EPA also considers that elimination of pollution through
material substitution will not be possible in all cases because SOCMI
products (many of which are listed as HAP's in section 112 of the Act)
cannot be eliminated from use without adverse economic impact.
Specifically, because the products of the SOCMI are used in the
production of polymers, resins, pesticides, pharmaceuticals, etc.,
elimination of a SOCMI product would affect not only the SOCMI producer
but also the downstream user of that SOCMI product. Many of the end-use
products (e.g., resins, pharmaceuticals, etc.) could not be made from
other materials. Thus, the EPA maintains that material substitution is
better left determined by the marketplace rather than by mandate
through a specific Federal requirement.
The EPA believes that the HON sufficiently encourages pollution
prevention. For example, within the provisions for process vents,
storage vessels, transfer operations, and wastewater collection and
treatment operations, there are compliance options that only specify a
percent reduction of HAP emissions. To comply with most of these
options, a source may use any means, including process changes or
recovery devices, to reduce emissions by the specified percent. While
process vent provisions do not allow use of recovery devices to achieve
the 98-percent reduction, the process vents provisions encourage the
use of process changes and recovery devices by including an option for
achieving a specified TRE value instead of adding control. Thus, the
owner or operator does not have to combust emissions to comply with the
standards. The storage vessel provisions encourage the use of floating
roofs to control emissions. Many of the requirements in the equipment
leaks and wastewater provisions also encourage pollution prevention
options to control emissions. The emissions averaging provisions
encourage pollution prevention by: (1) Not applying a discount factor
to credits generated by pollution prevention measures and (2) allowing
an additional five emission points to be included in an average if
pollution prevention measures are used.
G. Miscellaneous Technical Comments
1. Process Vents
a. Monitoring for Group 2 vents with TRE between 1 and 4. For the
final rule, the EPA maintains the same position as at proposal for
monitoring for process vents with a TRE between 1 and 4.
Several commenters recommended that the same monitoring provisions
for vents with a TRE between 1 and 4 be applied to vents with a TRE
greater than 4 due to process fluctuations. Several other commenters
requested that monitoring requirements for vent streams with a TRE
between 1 and 4 be reduced or eliminated because of the burden without
emissions reduction.
The rule requires monitoring, recordkeeping, and reporting
requirements for Group 2 vent streams with TRE index values between 1
and 4 to ensure those vents do not become Group 1 vents due to process
or recovery device operating variations and remain uncontrolled. Group
2 vents with TRE index values greater than 4 are not required to
monitor. An analysis was performed prior to proposal that shows that a
vent with TRE greater than 4 is unlikely to become Group 1 due to
process or recovery device operating fluctuations or measurement
uncertainties, whereas if TRE is greater than 4, it is important to
monitor recovery device operating parameters, because variations in
process or recovery device operations could cause such streams to
become Group 1. The EPA recognizes the uncertainty present in TRE
calculations, but decided that a sufficiently large safety factor has
been included for vents with a TRE greater than 4. The decision not to
require monitoring for process vents with a TRE greater than 4 reduces
the burden of regulation for both the industry and regulatory agencies.
b. Product accumulator vessels. For the final rule, the EPA has
deleted the term ``product accumulator vessel,'' and will regulate
equipment previously described as product accumulator vessels as
follows: (1) Vents from distillate receivers and product separators
will be regulated as process vents under subpart G; (2) hot wells will
be regulated by the wastewater provisions under subpart G; and (3)
surge control vessels and bottoms receivers will remain in subpart H.
The definition of process vent has been revised to include distillate
receivers and product separators.
Several commenters expressed concern due to the inconsistencies in
the proposed provisions for product accumulator vessels. The major
concerns included: (1) Multiple standards (process vents under subpart
G and equipment leaks under subpart H) would apply to the same vent;
(2) there are different compliance dates in subparts G and H; (3) the
proposed definition did not distinguish between product accumulator
vessels and storage vessels or other in-process vessels; and (4)
product accumulator vessels, which are point sources, would be
regulated under provisions that were intended for fugitive emissions
(i.e., equipment leaks). The commenters suggested eliminating the
inconsistencies by: (1) Deleting the subpart H requirements for product
accumulator vessels and regulating them as process vents under subpart
G; (2) allowing sources to select whether to comply with the
requirements of subpart G or subpart H; or (3) regulating product
accumulator vessels as storage vessels under subpart G. Several
commenters also suggested deleting from the HON the requirements for
product accumulator vessels associated with the non-SOCMI processes
subject to subpart H. The commenters preferred regulating such vessels
under future MACT standards for the appropriate source category.
The EPA agrees that there is need to clarify the applicability of
the HON to product accumulator vessels. Previous definitions and
control cost analyses for process vents have included indirect
releases, such as those from distillate receivers and product
separators. These emissions were clearly intended to be process vents
requiring 98-percent control under subpart G. Condensates from hot
wells were included in the proposed definition of wastewater and were
intended to be controlled at 95 percent under the subpart G provisions
for wastewater. Surge control vessels and bottoms receivers are
typically smaller than storage vessels subject to the HON, and have
relatively low emissions. Also, previous analyses on process vents have
not been clear on the inclusion of these vessels. Thus, the EPA decided
that surge control vessels and bottoms receivers will remain in subpart
H to be controlled at 95 percent. The term ``product accumulator
vessel'' has been deleted from the HON, and replaced with ``surge
control vessels and bottoms receivers.'' The above clarification
reflects the EPA's original intent regarding how the various equipment
types should be regulated and is not designed to alter the stringency
of the HON.
2. Storage Vessels
a. Time allowance for planned routine maintenance of control
devices. In the final rule, the EPA has increased the allowance for
sources to complete planned routine maintenance of a control device
from 72 hours per year to 240 hours per year.
Several commenters asserted that the proposed 72 hours per year for
routine maintenance of a control device would be insufficient for
reasons including: (1) Routine maintenance of a flare may require up to
7 to 10 days per year; (2) rebricking a thermal oxidizer requires at
least 7 days; (3) some States have included in incinerator air permits
an allowance of 10 days per year for routine maintenance; and (4) in
general, repair of boilers and water scrubbers requires more than 72
hours per year for routine maintenance. Several commenters requested
that the rule allow for longer routine maintenance periods by: (1)
Increasing the time allowance; (2) allowing extensions from the
permitting authority; or (3) requiring that storage vessels not be
filled during any routine maintenance that exceeds the 72-hour
allowance.
The EPA concluded that the 72-hour allowance for routine
maintenance is inadequate. After reevaluating the available
information, the EPA determined that increasing the time allowance to
240 hours (i.e., 10 days) would be the most reasonable approach to
address the need for more time to complete routine maintenance and to
be consistent with State air permitting activities. The EPA did not
choose either of the other two approaches suggested by the commenters
because of the additional burden associated with them. Specifically,
requiring that storage vessels not be filled during any routine
maintenance exceeding 72 hours would require the addition of equipment
to monitor liquid level for enforcement purposes. Further, allowing for
extensions for routine maintenance beyond the 72 hours would require
added reporting burden for both sources and permitting authorities.
While the EPA is allowing sources to utilize the full 240 hours to
perform routine maintenance on each control device, the EPA does not
expect that sources will utilize all 240 hours for all control devices,
because many types of control devices do not require 240 hours of
maintenance time per year. The EPA has included provisions in the
regulation that make sources accountable for their utilization of this
allowance. Sources are required to periodically (i.e., every six
months) report the routine maintenance performed and the amount of time
used to complete that routine maintenance. In addition, sources must
indicate the routine maintenance they expect to perform during the
following six months.
b. AP-42 Equations for emissions averaging with storage vessels.
For the final rule, the EPA will include the September 1985 version of
the AP-42 equations; however, the EPA will allow sources to utilize
either the September 1985 version or the October 1992 version (i.e.,
referenced as American Petroleum Institute Publication 2518, second
edition, October 1991) of the AP-42 equations for estimating breathing
losses from fixed roof storage vessels, for the purposes of emissions
averaging. Whichever set of equations a source selects, the source must
utilize the same set of equations for calculating breathing losses of
fixed roof storage vessels for estimating both credits and debits.
Two commenters recommended that the EPA update the storage vessel
emissions equations in the emissions averaging section of the final
rule in order to reflect the latest changes in the EPA document
``Compilation of Air Pollutant Emission Factors (AP-42)'' included in
chapter 12 of supplement E, entitled ``Storage of Organic Liquids.''
The EPA agrees that sources should be given the option to use the
latest AP-42 equations for estimating breathing loss emissions from
fixed roof storage vessels. However, the EPA will not require that
sources use these latest equations because it could be more burdensome
for some sources. The EPA determined that the October 1992 equations
are more site-specific and will require that sources make more
measurements of tank parameters because the EPA cannot provide default
values for some of the variables in the equations. Although the EPA
will allow sources to choose either the 1985 or the 1992 version of the
equations for estimating breathing losses from fixed roof storage
vessels, the source must use the same set of equations for estimating
both credits and debits from storage vessels for the purposes of
emissions averaging.
3. Transfer Operations
a. Determination of applicability and group status. For the final
rule, the EPA has clarified many of the applicability and group
determination provisions regarding transfer operations in the proposed
HON. The intent of these provisions has not changed.
Many commenters expressed confusion regarding whether the transfer
provisions refer to arms or transfer racks being loaded. Several
commenters requested that the EPA clarify that the HON is only
applicable to transfers of materials from SOCMI processes and not all
materials transferred at any given rack or arm.
The intent of the language in proposed Sec. 63.100(b)(5) of subpart
F and in the final Sec. 63.100(i) of subpart F is to assign loading
racks, loading arms, or loading hoses to a chemical manufacturing
process unit. If the chemical manufacturing process unit is subject to
the HON, then the loading rack, arm, or hose is also subject to the
HON.
Once it is determined that a rack, arm, or hose is subject to the
HON, group status must be determined. Group status is determined for a
transfer rack. A transfer rack is defined as the collection of all arms
or hoses that are assigned to a chemical manufacturing process unit
that is subject to the HON. For example, if a facility has a rack that
consists of eight arms and six of these arms are assigned to chemical
manufacturing process units subject to the HON and the other two load
petroleum refinery products not subject to HON, then the ``transfer
rack,'' as defined for the HON, is made up of the six arms that are
assigned to the chemical manufacturing process unit subject to the HON.
Group status must be determined based on the vapor pressures and
throughputs of the HAP's loaded at the arms that are subject to the
HON. In cases where a rack or arm(s) has been assigned to a chemical
manufacturing process unit subject to the HON, the rack or collection
of arms must be controlled during transfers of all HAP's regardless of
whether those HAP's were associated with SOCMI chemical manufacturing
process units.
The EPA determined that assigning equipment to be subject to the
HON would be easier from an enforcement and control perspective, as
opposed to assigning transfer operations. Also, by assigning equipment,
applicability will be more obvious when other rules are promulgated
affecting transfer operations under other source categories.
One commenter suggested that the organic HAP partial pressure
considering all the materials loaded at a specific loading arm or rack
should be used to determine applicability instead of the rack-weighted
vapor pressure.
The EPA agrees with the commenter's suggestion. The final transfer
provisions have been revised to replace the definition of rack-weighted
average vapor pressure with a definition for rack-weighted average
partial pressure.
b. Testing and Monitoring. The following changes have been made to
the testing and monitoring provisions for transfer operations:
(1) 15-minute monitoring of operating parameters is required
regardless of loading cycle time;
(2) The requirement for a performance test has been replaced with
design analysis for racks that load less than 11.8 million liters/yr;
and
(3) Performance test requirements have been clarified for
facilities using common control devices for both process vent and
transfer emissions or for emissions from multiple arms loading
simultaneously.
Several commenters contended that 5-minute monitoring and
recordkeeping requirements for loading cycles less than 3 hours were
overly burdensome and would serve no purpose. The commenters suggested
that the 15-minute monitoring and recordkeeping requirements of loading
cycles be made standard for all cycles in the final rule.
The EPA agrees with the commenters that 5-minute monitoring
intervals are not necessary. The EPA considers 15-minute monitoring to
provide sufficient statistical confidence in the performance of a
control device. Fifteen-minute monitoring intervals will also
adequately identify performance that is outside of the approved
operating parameter ranges.
Two commenters contended that it was unduly burdensome to require a
performance test duration of three loading cycles for infrequent
loading operations. Both commenters suggested that the EPA allow owners
or operators to conduct performance testing over only one loading cycle
for infrequent loading operations. One commenter expressed concerns
regarding simultaneous loadings and suggested that the EPA provide
performance test provisions for control devices shared between racks or
other emission points.
The EPA agrees with the commenters' assertion that the proposed
provisions for performance tests for infrequent loading operations were
burdensome. The EPA determined that for owners and operators loading
less than 11.8 million liters/year (3.12 million gal/yr) at a single
transfer rack, requiring a performance test on three loading cycles
could extend the completion of the performance test to 2 weeks or
longer. The EPA's intent in requiring testing during three different
loading cycles was to acquire sufficient data to ensure that a control
device was operating properly. The EPA has determined that a test of
one loading cycle would not provide sufficient data on the performance
of the control device; thus, requiring one loading cycle to be tested
would not be meaningful. Therefore, in the final rule a design
evaluation is allowed instead of a test for those racks with infrequent
loading (i.e., less than 11.8 million liters/year of materials loaded).
Although the proposed rule did not preclude shared control devices,
it was not clear how an owner or operator would demonstrate compliance.
Provisions have been added to the rule to clarify that in the case of a
control device being shared with process vents, the performance test
required under the process vent provisions is adequate for the transfer
provisions. For control devices shared among transfer racks or arms,
and where materials are simultaneously loaded, the performance test
requirements have been revised to be similar to the process vent
provisions: three one-hour performance test runs. Simultaneous loading
occurs when the beginning and ending times of loading cycles coincide
and overlap such that there is no interruption in vapor flow to the
control device; as one loading cycle is completed, another one begins
or has already begun.
4. Wastewater
a. Design steam stripper specifications. For the final rule, the
EPA has revised several of the specifications for the design steam
stripper. The following changes are incorporated into the final rule:
(1) The design steam stripper must have ten actual trays;
(2) The minimum wastewater feed temperature to the design steam
stripper must be 95 deg.C;
(3) The requirement to use a water-cooled condenser has been
deleted;
(4) The steam-to-feed ratio for the design steam stripper is 0.04
kilogram of steam for every one kilogram of wastewater;
(5) The steam heat value must be at least 2,765 kJ/kg (equivalent
to 690 kPa); and
(6) The maximum liquid tray loading is 67,000 l/hr-m2.
(i) Actual number of trays. Several commenters requested
clarification regarding the EPA's intent to specify theoretical or
actual trays. Based on additional analyses after the proposed rule was
published, the EPA has determined that a steam stripper that is
operated using 10 actual trays will achieve the required HAP target
removal efficiencies. These analyses are summarized in the promulgation
BID volume 2D and details of the analysis are in docket A-90-23.
(ii) Minimum wastewater feed temperature. The proposed rule
specified 35 deg.C as the feed temperature of wastewater to the steam
stripper. However, in the design analysis for the wastewater provisions
in both the proposed and final HON, the EPA has assumed that the feed
stream is heated to 95 deg.C before it enters the design steam
stripper. The feed stream is pre-heated to 95 deg.C by using a heat
exchanger to recover heat from the treated wastewater. The temperature
of 35 deg.C, which was inadvertently designated as the feed
temperature in the proposed rule, refers to the temperature of the
wastewater before it is pre-heated by the heat exchanger and sent to
the design steam stripper. The EPA has corrected this error and
included 95 deg.C in the final rule as the minimum wastewater feed
temperature to the steam stripper after the wastewater has been pre-
heated.
(iii) Condenser. The proposed rule required that a water-cooled
condenser with a maximum primary condenser outlet vapor temperature of
50 deg.C be used in conjunction with the design steam stripper.
Several commenters questioned why the EPA required the use of a water-
cooled condenser as part of the design steam stripper specifications.
The commenters suggested that the requirements for treatment devices in
section 63.138(h) were sufficient to control HAP emissions from
treatment devices. While the EPA agrees to eliminate the condenser from
the design steam stripper, it is clarified that a primary condenser, if
used, does not count toward the 95-percent control requirement because
this control requirement applies to non-condensibles.
(iv) Steam-to-feed ratio. Although no specific comments were
received on this issue, the EPA updated this number as part of the
analysis to revise the design steam stripper. The proposed rule
required a steam-to-feed ratio of 0.096 kilograms of steam for every
one kilogram of wastewater. The revised steam-to-feed ratio of 0.04
kilograms of steam for every one kilogram of wastewater optimizes the
efficiency of the design steam stripper to remove HAP's from
wastewater. The steam heat value specified for the design steam
stripper is 2765 kJ/kg, which is based on saturated steam at 690 kPa.
This parameter is specified in the design because use of a lower
quality steam would reduce the fraction of HAP's removed from the
wastewater treated by the design steam stripper.
(v) Maximum liquid tray loading. The maximum liquid tray loading in
the proposed rule was 39,900 l/hr-m 2. Because the liquid tray
loading is dependent on several other steam stripper parameters,
including the steam-to-feed ratio, the EPA has revised this input
parameter for the design steam stripper as a result of the revised
design analysis. The design analysis indicates that the revised maximum
liquid tray loading is 67,000 l/hr-m2.
(vi) Materials of construction. Although the rule does not specify
a particular type of steel that the SOCMI must use to construct the
design steam stripper, the cost estimates for the final rule include
the cost of stainless steel construction. The cost estimate for the
steam stripper in the proposed rule was based on carbon steel
construction. Numerous comments on this issue requested that the EPA
reevaluate the cost of constructing a design steam stripper based on
the use of stainless steel for construction. Commenters in favor of
stainless steel construction stated that stainless steel was stronger,
more durable, and more reliable than carbon steel. Also, stainless
steel is the minimum grade of building material that would be used by
the industry because of corrosion problems associated with carbon
steel. The EPA received no comments in favor of carbon steel
construction. The EPA has revised the cost estimate for the design
steam stripper using stainless steel and has determined that the design
steam stripper remains a cost-effective option for treating wastewater.
b. Fraction removed (Fr). In the final rule, the EPA has revised
the required Fr values (i.e., strippabilities) and assigned an Fr for
each of the individual compounds regulated by the wastewater provisions
(i.e., compounds listed on table 9). Several commenters requested that
the EPA:
(1) Re-evaluate the Fr estimates in the proposed rule using actual
Henry's law constants at 100 deg.C; and
(2) Assign a better estimate of individual compound-specific Fr
values rather than use the strippability groups.
In response to comments, the EPA conducted a literature search to
determine peer-reviewed Henry's law constants at 25 and 100 deg.C, and
selected the best estimates available for each compound. The revised
Henry's law constants at 100 deg.C were used to estimate Fr values for
each of the 76 compounds in the wastewater provisions of the final
rule. The report documenting the development of the constants is titled
``Henry's Law Constants for the 83 HAP's Regulated in the Proposed HON
Wastewater Provisions,'' and is provided in Docket A-90-23. In the
proposed rule, each of the compounds listed on table 9 was assigned to
one of these strippability groups. The strippability groups represented
a range of actual strippabilities with a single target removal
efficiency (i.e., strippability). The EPA agreed with commenters that
assigning HAP's to a specific strippability group could preclude
compliance with the standard for some compounds. Therefore, the EPA
generated compound-specific Fr values based on the revised Henry's law
constants for each of the compounds listed in table 9 of subpart G.
Additionally, the EPA has revised the proposed compliance option that
required compounds listed on table 9 of subpart G to meet the target
removal efficiencies that were associated with the strippability
groups. The compliance option in the final rule requires that the owner
or operator treat compounds to meet their individual Fr's, which are
assigned in table 9 of subpart G.
c. Emission estimates--(i) Wastewater models. For the final rule,
the EPA has revised the emission models for lift stations, junction
boxes, open sumps, trapped drains, and weirs using a study provided by
one commenter, in which the emissions of organic HAP's were measured.
The EPA reviewed the information and determined that the report and
source data were appropriate to use to improve the emission models. The
air emission model for weirs was modified to account for gas-phase
resistance. These revised models also incorporate an approach for
modeling site-specific configurations of lift stations, junction boxes,
sumps, drains, and weirs that are currently used by the SOCMI. The
models used to calculate the Fe's are described in ``Estimation of Air
Emission Factors from Airflow in Wastewater Collection Systems,''
November 30, 1993.
(ii) Collection and treatment scenarios. The EPA also revised the
SOCMI source wastewater collection and treatment scenarios based on
information provided by one commenter, EPA staff observations, and
State and EPA environmental regulatory enforcement representatives from
Texas, Louisiana, and New Jersey. Several commenters stated that
baseline emission estimates should be revised based on emission data
and SOCMI source scenarios that were submitted to the EPA during the
public comment period. The EPA considered and incorporated, where
appropriate, data that were submitted by commenters.
(iii) Fraction emitted (Fe) values. The revised Fe's in the final
rule are based on two different wastewater collection and treatment
system scenarios with three different levels of control, and with each
control level weighted based on the expected level of occurrence. The
three control levels and the corresponding fraction of occurrence are:
(1) Uncontrolled = 0.50; (2) medium degree of control = 0.40; and (3)
higher degree of control = 0.10. Values for Fe for individual compounds
were calculated for each of the two scenarios and the control
distributions summarized above. The resulting two control weighted
average Fe's for each individual compound (one for each scenario) were
averaged together, resulting in the final Fe values. This procedure is
described in detail in the memorandum, ``Estimation of Air Emissions
from Model Wastewater Collection and Treatment Plants Systems,''
February 2, 1994.
The EPA used revised scenarios and emission models in conjunction
with the revised Henry's law constants to revise the Fe values for each
compound listed on table 9. The EPA used the revised Fe values to
calculate the baseline emission estimates for the final rule and to re-
evaluate which organic HAP's should be subject to the wastewater
provisions of the HON. Based on the revised Fe's, the EPA has deleted
seven compounds from the final rule. Each of these compounds is
unlikely to be emitted in significant quantities from the collection
system (due to the low Fe value) and will be readily biodegraded upon
reaching the biological treatment unit.
Several commenters stated that some of the HAP's regulated by the
proposed HON are non-volatile or semi-volatile, are not likely to be
emitted from wastewater, and should be deleted. Based on the revised Fe
values, the EPA has removed the following seven compounds from the
wastewater provisions of the final rule: Aniline (62533); 2-
chloroacetophenone (532274); o-cresol (95487); 3,3-dimethylbenzidine
(119937); diethylene glycol diethyl ether (112367); diethylene glycol
dimethyl ether (111966); and ethylene glycol monoethyl ether acetate
(111159). An increase in baseline emission estimates for wastewater of
9 percent resulted from the emission estimate revisions. The primary
reasons for the change were:
(1) Revised Henry's law constants;
(2) Revised wastewater emission models for lift stations, junction
boxes, open sumps, and open drains; and
(3) Revised scenarios and Fe values.
d. Wastewater tanks. In the final rule, the EPA requires any owner
or operator of a SOCMI source who is subject to the wastewater tank
provisions in Sec. 63.133 of subpart G to calculate the vapor pressure
and the capacity of the tank in order to determine the applicable
compliance options. The proposed rule did not require the owner or
operator to determine the vapor pressure or the tank capacity, but
rather required the same compliance options for wastewater tanks
regardless of size and vapor pressure.
Several commenters requested the following changes to the proposed
wastewater tank provisions including:
(1) That wastewater tanks be managed in accordance with the
proposed storage vessel provisions;
(2) That wastewater tank requirements be based on the partial
pressure of the liquid in the tank;
(3) That wastewater tank requirements be based on the capacity of
the tank; and
(4) That wastewater tanks operated under negative pressure be
exempt from using Method 21 for leak detection.
In response to comments, the EPA has incorporated several changes
to the wastewater tank provisions. The EPA continues to require
emission controls on all wastewater tanks that manage Group 1
wastewater streams or residuals generated from Group 1 wastewater
streams. However, the EPA has included capacity and maximum partial
vapor pressure thresholds that are consistent with those of the storage
vessel provisions. The EPA also is allowing the owner or operator to
demonstrate compliance with the wastewater tank provisions by
installing only a fixed roof if the tank meets any of the following
criteria: (1) Is less than 75 m\3\; (2) is greater than or equal to 75
m\3\ and less than 151 m\3\ and has a maximum true vapor pressure less
than 13 kPa; or (3) is greater than or equal to 151 m\3\ and has a
maximum true vapor pressure less than 5.2 kPa. The EPA has determined
that a fixed roof is sufficient to suppress emissions from any
wastewater tank that meets the preceding criteria. In addition, the EPA
has dropped the requirement for annual Method 21 inspections on
wastewater tanks. In the final rule, Method 21 inspections are required
initially and annual visual inspections are required. Furthermore, the
EPA has added a provision to the final rule which states that any
wastewater tank operated and maintained under negative pressure is not
required to comply with the requirements for leak detection by Method
21 of 40 CFR part 60, appendix A because it cannot emit.
e. Containers. In the final rule, the EPA has included a de minimis
capacity of 0.1 m\3\ (i.e., approximately 26.4 gal) in the definition
of container, below which the container is not subject to the HON. For
the purpose of monitoring and submerged filling, the EPA distinguishes
between containers that are less than or equal to 0.42 m\3\ (i.e.,
approximately 110 gal) and those that exceed 0.42 m\3\. Furthermore,
the EPA has changed the requirements for a submerged fill pipe. In the
final rule, a submerged fill pipe outlet shall extend to no more than 6
inches or within two fill pipe diameters of the bottom of the container
while the container is being filled. Submerged filling is not required
for containers with capacities less than or equal to 0.42 cubic meters.
The proposed rule did not distinguish between container capacities.
All containers regardless of size were required to meet the same
requirements. The EPA received comments in favor of changing the
monitoring requirements and establishing a de minimis container size.
Specifically, commenters asserted that the HON should not apply to
either very small containers which include lab sample bottles or
containers with small capacities such as 30 gallons or 55 gallons.
Commenters also claimed that the requirement to use Method 21 for
containers, particularly those that are on site for a short time, would
be burdensome.
In response to comments, the EPA has established a de minimis
capacity of 0.1 m\3\, which exempts lab bottles and other very small
containers from the HON. The EPA has also provided an additional
compliance option for leak detection monitoring for containers with
capacities less than or equal to 0.42 m\3\. If a container has a
capacity less than or equal to 0.42 m\3\, the owner or operator may
either: (1) Use Method 21 initially to demonstrate that the container
is not leaking; or (2) document that the container meets DOT
specifications and testing requirements in 49 CFR part 178. The EPA has
determined that if an owner or operator is in compliance with the DOT
specifications and testing requirements in 49 CFR part 178, no
additional requirements are necessary to ensure that the containers do
not leak. The owner or operator must maintain records documenting the
Method 21 test for non-DOT containers. For DOT-approved containers, the
owner or operator does not need to keep a record because compliance may
be determined by a visual inspection.
The EPA also has reduced the monitoring burden for larger
containers with a capacity greater than 0.42 m\3\. Whereas the proposed
rule specified the use of Method 21 initially and annually, the final
rule requires the use of Method 21 initially and allows annual visual
inspections thereafter.
f. Method 304 and method 305. No major changes have been made to
Method 304. However, the EPA has included both Method 304A and 304B in
the final rule. Commenters requested that Method 304 allow more
flexibility in choice of laboratory equipment, clarifier design, and
some operating parameters. The EPA agreed with the commenters and has
added options to increase the flexibility of the method, such as
allowing air cylinders in addition to oxygen cylinders to aerate the
microbial population. The additional flexibility added to the method
does not reduce the accuracy or precision of the method results and
could in some cases improve the results by better representing the
actual biological treatment process. Changes made to the final Methods
304A and 304B are in section 4.0 of BID volume 2E.
Several commenters misunderstood the requirements of Method 305.
The EPA discusses clarifications to the method in volume 2B of the BID.
One commenter questioned why the EPA developed Method 305 when other
methods, such as the 600 series for water and wastewater, were
available. Another commenter was concerned whether the test method
results are realistic.
To determine the significance of HAP emissions from wastewater, it
is more important to know how likely a HAP is to leave the wastewater
and go into the atmosphere than to know the actual concentration of the
HAP in the wastewater. The EPA developed Method 305 to provide a
relative measure of the emission potential of wastewater. Other methods
measure the actual concentration of pollutants; no other methods define
the relative measure of emission potential. Although the results of
Method 305 do not necessarily represent the actual pollutant
concentration in wastewater, the test method results are realistic--the
results measure the relative emission potential. The parameters of the
test method were chosen to define emission potential based on
mathematical modeling of actual data collected from various sources
throughout the country. In addition, the regulation requires that
concentration be reported in terms of Method 305 results; it does not
require the owner or operator to use Method 305. The owner or operator
may use any method that has been validated by section 5.1 or 5.3 of
Method 301 and converted to Method 305 results using the appropriate
Fm factor.
g. Water seal controls. The EPA revised the requirements for water
seals. In Sec. 63.137(e) of the final wastewater provisions if a water
seal is used on a drain hub receiving a Group 1 wastewater stream, the
owner or operator shall either extend the drain pipe discharging the
wastewater below the liquid surface in the water seal, or install a
flexible cap (or other enclosure which restricts wind motion) that
encloses the space between the drain discharging the wastewater to the
drain hub receiving the wastewater.
VI. Summary of Significant Comments and Changes To Proposed Subpart
H
Approximately 60 letters commenting on proposed subpart H were
received; most of these letters contained multiple comments. The EPA's
responses to these comments can be found in the BID referenced in the
ADDRESSES listing in this preamble. The most significant comments and
responses for the equipment leak standard (subpart H) are summarized in
this section of the preamble.
A. Applicability
1. SOCMI Processes
Many commenters requested that EPA make the list of SOCMI processes
in subpart H consistent with the list in subpart F and that the EPA
correct errors in nomenclature and CAS numbers provided. Some of these
commenters also recommended consolidation of all the applicability
provisions for SOCMI processes in subpart F. As discussed in section
V.A.1 of this preamble, the lists of SOCMI processes have been
consolidated into a single list in subpart F and errors in CAS numbers
have been corrected. The revised subpart F presents all the criteria
for determining applicability of the HON for SOCMI processes. The EPA
believes this revised organization will be easier and more efficient to
use.
2. The Seven Non-SOCMI Processes
At proposal, the provisions of subpart H applied to both SOCMI
processes and to equipment handling specific chemicals for seven listed
non-SOCMI processes. Subparts F and H in the proposed rule presented
the applicability provisions for both SOCMI and non-SOCMI processes. In
the final rule, the applicability provisions for the non-SOCMI
processes are presented in a separate subpart, subpart I, from the
SOCMI applicability provisions which are specified in subpart F.
Subpart I identifies the specific non-SOCMI processes that are subject
to the provisions of subpart H. In addition, subpart I presents
definitions and general information on compliance, reporting, and
recordkeeping.
a. Separate from SOCMI category. A number of commenters thought
that the non-SOCMI processes subject to subpart H should be regulated
separately from the SOCMI processes. These commenters thought that
combining the non-SOCMI processes in a standard for SOCMI processes
could result in piecemeal regulation, overlapping section 112(d)
regulations, and confusion for regulatory agencies. A few of these
commenters also argued that regulation of the non-SOCMI processes
should be deferred until the rest of the section 112(d) emission
standard is issued for each specific non-SOCMI process.
The EPA agrees with the commenters' suggestions for reorganization
of the regulatory provisions into separate subparts. The applicability
provisions for the non-SOCMI processes have been placed in subpart I.
Subpart I refers to subpart H for the substantive requirements. As
discussed in section VI.A.2.b through e of this preamble and in the
BID, subpart I contains revised definitions for some of the non-SOCMI
processes. The definitions were revised to specifically identify the
intended processes and to directly correspond to the categories listed
in the source category list (57 FR 31576). The EPA expects that these
changes will minimize the possibility for confusion and development of
overlapping regulations. The EPA does not agree with the suggestion to
defer the applicability of the equipment leak standard to the non-SOCMI
processes until requirements for the other emission points are issued.
This change suggested by the commenters is not consistent with the
spirit of the negotiated agreement.
b. Chlorine production. Under the negotiated agreement, chlorine
production processes that used carbon tetrachloride as a diluent for
nitrogen trichloride or as scrubbing liquid to recover chlorine from
the liquefaction of tail gas would implement the equipment leak
provisions for equipment in 5 percent, or greater, carbon tetrachloride
service. At the Fourth Meeting of the Parties to the Montreal Protocol
in November 1992, the United States Government and the Other Parties
agreed to accelerate the phase-out schedule for carbon tetrachloride by
requiring a reduction from 1989 levels of 85 percent in 1995 and a
complete phase-out by January 1, 1996. Because of this development,
chlorine producers will cease use of carbon tetrachloride by January 1,
1996. Therefore, several commenters questioned the value of continued
application of subpart H to chlorine production processes.
The EPA agrees that the reasons for application of the negotiated
equipment leak rule to chlorine production processes have significantly
diminished and will disappear entirely in the next 2 years. Therefore,
to avoid essentially duplicative regulation of the same operations,
chlorine production has been removed from the list of seven additional
processes subject to subpart H.
c. Pesticide production. One commenter argued that the proposed
definition of ``pesticide production'' defines a source category that
is broader than any category in the agricultural chemical production
industry grouping identified in the List of Source Categories (57 FR
31576), or in the proposed Schedule for Promulgation of Emission
Standards (57 FR 44147). The commenter noted that only the production
of Captafol, Captan, Chlorothalonil, Dacthal(tm), and Tordon(tm) were
listed in 57 FR 31576 or 57 FR 44147 as being specifically regulated by
the HON equipment leak standard. The commenter argued that if EPA wants
to update the source category list, EPA must comply with statutory
requirements to include only categories of major sources and area
sources where a finding of adverse health effects has been made. The
commenter recommended that the definition of pesticide production in
subpart H be modified to regulate equipment leaks only from the
production of Captafol, Captan, Chlorothalonil, DacthalTM, and
TordonTM.
The definition for pesticide production in proposed subpart H was
developed in the regulatory negotiation before creation of the source
category list. The source category list and schedule (57 FR 31576 and
57 FR 44147) identifies the pesticide production processes that EPA had
information on at the time of the negotiations on the equipment leak
standard. Therefore, subpart H is being applied only to the five
production processes identified in the source category list (production
of Captafol, Captan, Chlorothalonil, DacthalTM, and
TordonTM). As EPA obtains information on other pesticide
processes, these processes will be added to the source category list in
the future and standards will be developed.
d. Chlorinated hydrocarbon use. Numerous inquiries have been
received from members of the public questioning whether, through the
``chlorinated hydrocarbon use category'' in subpart H, the EPA intended
subpart H to apply to all operations that use chlorinated organic
solvents. A few written comments were also received requesting
clarification that this definition applied to production operations
only.
The term ``chlorinated hydrocarbon use'' was a label created in the
regulatory negotiation to refer to a number of specific miscellaneous
chemical manufacturing processes that used chlorinated solvents as a
solvent or processing aid. Examples of the specific processes included
under this term are production of polycarbonate and production of
polysulfide rubber. The provisions of subpart H were intended to apply
only to the specific types of processes listed in the definition and
not to all use of chlorinated organic solvents. Because of the
confusion created by the label applied to these processes, the final
rule does not use the term chlorinated hydrocarbon use. Instead,
subpart I specifically identifies the processes subject to subpart H.
e. Miscellaneous butadiene use. Comments were received requesting
that the definition of this term clarify that these are processes
producing chemicals or chemical products.
The EPA agrees that ``miscellaneous butadiene use'' refers to a
number of miscellaneous chemical manufacturing processes that use
butadiene to produce other chemicals or chemical products. To eliminate
the possibility of confusion regarding the applicability, subpart I
lists the specific processes subject to H and the term ``miscellaneous
butadiene use'' is not used in the final rule.
B. Compliance Schedule
1. Consistency with Subpart G
Unlike most standards, compliance with the provisions of subpart H
is phased in by type of chemical manufacturing process. The proposed
subpart H divided the regulated processes into five distinct groups to
which the provisions would apply beginning 6 months after publication
of the final rule in the Federal Register. Thereafter, the rule would
apply to another group of processes every 3 months. The final rule for
subpart H uses the same approach. In the proposed and final provisions
in subpart G, sources are required to comply by 3 years from date of
publication of the final rule in the Federal Register.
Many commenters requested a compliance schedule for subpart H
similar to the 3-year schedule provided under subpart G. Several
commenters argued that the 6-to-18-month compliance period in proposed
subpart H did not take into consideration the implementation problems
that could arise during installation of required equipment. A few
commenters thought that proposed subpart H did not permit applications
for compliance extensions.
The EPA does not agree with the commenters that sources should be
allowed up to 3 years to comply with the provisions in subpart H.
Subpart H consists of a combination of work practice requirements for
many equipment components and equipment standards for compressors,
sampling systems, open ended lines or valves, and pressure relief
valves. Unlike the requirements in subpart G, the equipment required by
subpart H should not involve long periods of time for design,
construction, and installation. The commenters did not provide any
information that would justify establishing a source-category-wide
compliance schedule for subpart H similar to that provided for subpart
G. The EPA recognizes that there may be circumstances present in
individual facilities where an extension is appropriate for compliance
with certain requirements in subpart H. In such cases, the owner or
operator may request an extension of compliance through the provisions
of 40 CFR 63.6(i)(4). Section 63.182(a)(6) has been added to subpart H
to clarify that extensions of compliance may be requested if additional
time is necessary for installation of equipment required by subpart H.
2. Phase-In of Valve Provisions
The proposed standard for valves was structured to be implemented
in three phases, with lower leak definitions in each phase. In the
first and second phases of the proposed standard, monitoring was to be
conducted quarterly. In the third phase of the proposed standard, the
monitoring frequency would be determined by the percent leaking valves,
with the best performers having an annual monitoring requirement. The
final standard retains the phased-in implementation of the proposed
standard and the proposed monitoring frequencies.
Many commenters requested that the rule be modified to allow
facilities to begin Phase III of the valve provisions on the
applicability date. Some of these commenters thought facilities that
qualify for reduced monitoring frequency should be allowed to do so at
the earliest possible date. Other commenters thought the rule should
allow the owner or operator to elect the monitoring frequency based on
the source's current status since records may not have been retained.
The commenters submitted that disallowing early adoption of Phase III
would penalize facilities that have implemented the proposed rule
before required or that have established low leak rates through
existing programs.
The EPA agrees that the final rule should allow owners or operators
the flexibility to initiate Phase III at any time, and it was intended
that this option would be available. Subpart H has been revised to
clarify this point. This clarification does not, however, allow an
owner or operator to elect to use reduced monitoring frequencies
without Method 21 data to document achievement of lower leak rates for
the required periods.
C. Selection of Requirements
1. Closed Vent Systems and Control Devices
At proposal, both subparts G and H contained requirements for
monitoring inspections of closed vent systems. In the final rule, the
inconsistencies between the proposed provisions in subparts G and H
have been eliminated and the two sets of provisions have been
coordinated. The final subparts G and H each include provisions for
closed vent systems.
Several commenters recommended that all provisions for closed vent
systems be consolidated in subpart H and all inconsistencies
eliminated. These commenters speculated that different provisions for
closed vent systems serving different operations would increase
confusion, recordkeeping costs, and potential for recordkeeping
violations. Some of these commenters questioned the basis for treating
valves, connectors, and compressors in closed vent systems separately
from the same equipment in the process. The commenters noted that the
equipment is either in low pressure or vacuum service and the annual
inspection requirements are of no environmental benefit.
The EPA evaluated the commenters' suggestions and agrees that it
would be appropriate to have a consistent set of provisions for closed
vent systems in the rule. A uniform set of provisions for closed vent
systems will benefit both State and Federal enforcement programs and
industry by both reducing review time and complexity of record systems.
Because subpart G also included requirements for inspections of
equipment other than closed vent systems, the closed vent system
provisions in subpart G were not consolidated into subpart H.
The EPA also reevaluated the provisions requiring annual Method 21
monitoring of closed vent systems. Closed vent systems in chemical
plants and refineries are constructed of piping and connections and are
operated at low pressures or under vacuum. An assessment of recent data
and experience from implementation of existing standards under 40 CFR
part 60 and part 61 showed that only rarely are leaking connectors and
other equipment identified through the annual Method 21 inspections of
closed-vent systems. As discussed in the preamble to the proposed rule
(57 FR 62666 and 57 FR 62676), connectors have very low leak
frequencies and once leak-tight they remain leak-tight. Consequently,
the final rule only requires an initial Method 21 demonstration that
all connections and other equipment in closed vent systems are operated
with instrument readings less than 500 ppm and annual inspections for
indications of leaks (visual, olfactory, or audible). The EPA believes
that this requirement along with the requirement for flow indicators or
car seals on by-pass lines that could divert emissions from the control
device to the atmosphere will ensure emissions are controlled as
required.
The EPA would like to clarify that the provisions for inspections
of closed vent systems do not apply if the closed vent system is
operated in vacuum service. The closed vent systems provisions in
section 63.148 of subpart G and section 63.172 of subpart H have been
revised to clarify that these provisions do not apply if the system is
operated under vacuum.
2. Inaccessible Connectors
Proposed subpart H excluded connectors that ``were unable to be
reached from a 7.6-meter (25-foot) portable scaffold on the ground, and
were greater than 2 meters above a support surface'' from the
monitoring provisions. In the final rule, EPA has revised this
definition to reflect concerns with safety of monitoring connectors
accessible only via portable scaffolds and to clarify the original
intent.
Several commenters requested that the definition of inaccessible
connectors be revised to be any that are greater than 2 meters above a
support surface and, thus, the same as the difficult-to-monitor valve
definition. The commenters objected that portable scaffolds presented
safety and practical concerns due to limitations on access due to
equipment spacing, explosion hazards, and risks of damaging electrical
cables and piping.
During the Committee discussions in negotiation of these
provisions, the portable scaffolding envisioned was a wheeled scissor-
lift platform that would sit on the ground below the monitoring or
repair location. Portable scaffolding was not envisioned as including
field-erected scaffolding or movement over grassed or unstable stone
covered areas below pipelines because of concerns these operations
would endanger the monitoring personnel's lives. Because the proposed
rule's language was not clear on this point, the EPA agrees that
clarification of the term ``portable scaffold'' is warranted. A
definition has been added to the final rule. The EPA believes that
clarifications in subpart F to the definition of production process
should also address commenters' concerns regarding monitoring
connectors in interunit pipelines.
3. Response Factor Adjustments
The proposed standard required correction of the Method 21
instrument readings if the response factor for the process fluid was 3
or greater, and documentation of the response factor for every process
stream subject to the standard. The proposed standard also specified
the use of methane as the sole reference gas for the response factors.
The final standard retains the use of methane as the sole basis for
response factors, but revises the requirements for response factor
adjustment to ensure the instrument meets specifications of Method 21.
The final standard, thus, does not require process stream response
factor adjustments.
Several commenters objected to the proposed requirement to
determine response factors for process streams arguing that most
factors are less than 3, the difference in number of leaks detected
will be small, and the program complication will be immense. Another
issue with the proposed requirement was that the equation for
calculating response factors of mixtures was applicable only to gas
mixtures. For mixtures of liquids, the equation would have to be
adjusted by the vapor pressure of each component. A number of
commenters were also concerned that the stipulation of methane as the
sole reference gas would preclude the use of some monitoring
instruments.
As discussed in the proposed notice (57 FR 62682), the Committee
decided to limit the acceptable range of response factors to ensure
that the effect of the standard could not be significantly altered by
the monitoring instrument used or by the composition of streams
monitored. At the time of the negotiations, few response factors at 500
ppm were available and it was believed that most SOCMI processes would
have no more than four to five compounds present in any given stream.
Based on these assumptions, the Committee thought that the requirement
to correct any response factors greater than 3 would not impose
unproductive costs or be especially burdensome.
The EPA reevaluated this proposed requirement in light of the
public comments and the experience gained by chemical plants that have
implemented the negotiated rule. Experience with the correction for
response factors has shown the proposed provisions to be significantly
more burdensome than originally anticipated. Specifically, several
facilities have reported that instead of quantifying 4 to 5 compounds
in some streams, they are quantifying 50 to 100 compounds. In some
cases, owners or operators have elected to correct all instrument
readings by the highest response factor for any compound in the process
rather than undertake the effort associated with the stream specific
corrections.
The EPA also reviewed the reasons the Committee originally
considered requiring adjustment of screening values by response
factors. The response factor adjustment originated in Committee
discussions on studies to improve the emission estimates. (Response
factors are used to correct instrument readings to indicate actual
concentrations for developing emission estimates.) The appropriateness
of adjusting screening values in the leak detection and repair
provisions was not considered. These adjustments will not change the
emission reductions achieved from implementing the standard. Therefore,
EPA believes that eliminating this provision does not change the effect
of the standard and preserves the Committee's intent of minimizing
unproductive effort.
The final standard requires the owner or operator to use a
monitoring instrument that meets the specifications of Method 21 of
appendix A of 40 CFR part 60. The proposed provisions in
Sec. 63.180(b)(6) have been removed from the standard. It has been
clarified that the leak definitions are expressed in terms of total
VOC, and not speciated concentration readings.
A number of commenters also objected to the specification of
methane as the calibration gas for the Method 21 monitoring. These
commenters were concerned that this specification precluded the use of
photoionization detectors and recommended the rule allow use of
calibration gas best suited to the detector.
The provisions in Sec. 63.180(b)(4) designate methane as the
calibration gas to identify methane as the sole reference gas for
calculation of response factors. If an instrument has a poor response
or no response to methane, a calibration gas other than methane may be
used. In cases where the instrument's response factor is greater than
10, the instrument readings must be converted to a methane basis as
described in section 3.2 of Method 21. Section 63.180(b)(4) has been
clarified on this point.
D. Recordkeeping and Reporting
1. Consistency With Subpart G and General Provisions Reporting
Requirements
Proposed subpart H required owners or operators of sources to
submit an initial report and semiannual reports thereafter. The initial
reports were to be submitted within 90 days of the applicability date
for each group of chemical production processes. In the final rule, the
system of reports in subpart H has been revised to be compatible with
the five-report system of subpart G, and the relationship of the
general provisions to subpart H has been clarified.
Several commenters suggested that subpart H use a system of reports
similar to that specified in subpart G and that the final standard
should provide a means to coordinate reporting for processes in
different applicability groups. The commenters urged EPA to make these
changes to facilitate management and enforcement of the provisions. A
few commenters questioned the need for semiannual reporting when 70 to
95 percent of the components at a facility would be monitored on an
annual basis. Additionally, the need for certain reports was questioned
by several commenters.
The EPA agrees that, to the extent possible, reporting requirements
for subpart H should be consistent with those of subpart G. A
consistent system will, as noted by the commenters, make management of
the program easier for the permit authority as well as the source. As
proposed, an owner or operator of a source with processes in each of
the five applicability groups could be required to submit as many as
eight reports each year. Therefore, to streamline reporting
requirements and minimize potential confusion, the following changes
have been made to the proposed requirements:
(1) Submit the compliance notification report no later than 90 days
after the applicability date for the group of chemical processes and
the periodic reports every 6 months thereafter;
(2) Allow the source to adjust the reporting schedule to combine
the periodic reports for subpart H with those for subpart G once the
source comes into compliance with the provisions in subpart G; and
(3) Consolidation of several special reports into the periodic
report.
The final standard does not allow annual reporting as requested by
several commenters. Although many components may be monitored on an
annual basis, the monitoring frequency for pumps and agitators is
monthly and annual reporting would not be consistent with the reporting
system in subpart G. The operating permit provisions of the Act,
section 504(a), also requires reporting to be at least semiannual.
Additionally, unless all units at a source are on the same monitoring
schedule, the source would have to submit multiple annual reports. The
EPA believes that consolidating the reporting into semiannual reports
for G and H is more efficient for both industry and enforcement
agencies.
2. Burden of Recordkeeping and Reporting Requirements
The vast majority of the comments received on proposed subpart H
concerned the burden of the recordkeeping and reporting requirements.
Some commenters argued that the proposed subpart H would require from
1.5 to 2.5 person-years effort for the initial report and from 1 to 1.5
person-years effort for subsequent reports. These commenters thought
that the proposed requirements were not necessary to ensure
enforceability of or compliance with the provisions. Many comments were
received regarding documentation of equipment not subject to the
provisions, compatibility with computerized systems, and duplicative
records and reports. The detailed summary of these comments and EPA's
response is provided in chapter 5 of promulgation BID volume 2A.
In light of these comments, EPA reevaluated the proposed
requirements to ensure that only those records and reports essential
for enforcement of the standard are required. This review showed that
some of the commenters' concerns arose from a lack of clarity in the
proposed standard regarding actual records required for some of the
provisions and other concerns arose from overlapping or duplicative
requirements. It was also determined that some provisions should be
redrafted to be compatible with computerized data management systems
and the revised provisions would still provide the information
necessary to demonstrate compliance. Examples of such changes include:
allowing a source to maintain on file a written procedure outlining the
conditions for delay of repair and requiring certain records only for
nonautomated systems. The EPA also reviewed the proposed standard to
identify implied recordkeeping requirements and to specify all the
required records in Sec. 63.181.
VII. Administrative Requirements
A. Docket
The docket is an organized and complete file of all the information
considered by the EPA in the development of this rulemaking. The docket
is a dynamic file, since material is added throughout the rulemaking
development. The docketing system is intended to allow the public to
readily identify and locate documents so that they can effectively
participate in the rulemaking process. Along with the statement of
basis and purpose of the proposed and promulgated standards and the
EPA's responses to significant comments, the contents of the docket,
except for interagency review materials, will serve as the record in
case of judicial review [section 307(d)(7)(A)].
B. Executive Order 12866
This regulation has been reviewed in accordance with Executive
Order 12866. Under the terms of the Order, the Administrator has
assessed the potential costs and benefits of this regulatory action.
The methods for and results of these cost and benefit analyses are
described in the HON's Regulatory Impact Analysis (RIA). The RIA was
included in the HON docket at proposal, and thus it was made available
for public comment.
Executive Order 12866 also requires that the record for
``significant'' rules include an assessment of the potentially
effective and reasonably feasible alternatives to the planned action.
The potentially effective and reasonably feasible alternatives to the
control requirements in the HON were also analyzed as part of the rule
development process. The methods for and results of these analyses are
described in the HON's Background Information Document (BID). The BID
was included in the HON docket at proposal, and thus it was also
available for public comment. In addition, many of the alternative
requirements considered by the Administrator were described in the
preamble for the HON proposal.
The potential costs associated with alternatives selected by the
Administrator for this rule are primarily the result of statutory
requirements. All elements of the cost that are not directly
attributable to statutory requirements were deemed appropriate because
the Administrator determined that they were necessary for administering
this program effectively and efficiently. In assessing the potential
costs and benefits--both quantitative and qualitative--of this rule,
the Administrator has determined that the benefits justify the costs.
Burdens specifically associated with information collection
requirements are identified and explained in the next section of this
preamble under the heading Paperwork Reduction Act of 1980.
The Administrator has also determined that this regulatory action
does not unduly interfere with State, local and tribal governments in
the exercise of their governmental functions.
C. Paperwork Reduction Act
The information collection requirements in this rule have been
submitted for approval to the OMB under the Paperwork Reduction Act, 44
U.S.C. 3501 et seq. An Information Collection Request document has been
prepared by the EPA (ICR No. 1414.02), and a copy may be obtained from
Sandy Farmer, Information Policy Branch, EPA, 401 M Street, SW. (2136),
Washington, DC 20460, or by calling (202) 260-2740. These requirements
are not effective until OMB approves them and a technical amendment to
that effect is published in the Federal Register.
This collection of information has an estimated reporting burden
averaging 1,400 hours per response, and an estimated annual
recordkeeping burden averaging 5,400 hours per respondent. These
estimates include time for reviewing instructions, searching existing
data sources, gathering and maintaining the data needed, and completing
and reviewing the collection of information.
Send comments regarding the burden estimate or any other aspect of
this collection of information, including suggestions for reducing this
burden, to Chief, Information Policy Branch, EPA, 401 M Street, SW.,
(Mail code 2136); Washington, DC 20460; and to the Office of
Information and Regulatory Affairs, Office of Management and Budget,
Washington, DC 20503, marked ``Attention: Desk Officer for EPA.''
D. Regulatory Flexibility Act
The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires EPA
to consider potential impacts of proposed regulations on small
``entities.'' If a preliminary analysis indicates that a proposed
regulation would have a significant economic impact on 20 percent or
more of small entities, then a regulatory flexibility analysis must be
prepared.
Regulatory impacts are considered significant if any of the
following criteria are met:
(1) Compliance increases annual production costs by more than 5
percent, assuming costs are passed on to consumers;
(2) Compliance costs as a percentage of sales for small entities
are at least 10 percent more than compliance costs as a percentage of
sales for large entities;
(3) Capital costs of compliance represent a ``significant'' portion
of capital available to small entities, considering internal cash flow
plus external financial capabilities; or
(4) Regulatory requirements are likely to result in closures of
small entities.
Firms in the chemical industry are classified as small by the Small
Business Administration (SBA) if employment is less than 500 to less
than 1,000 employees depending on the particular Standard Industrial
Classification (SIC) of the firm. The firms classified as small by this
definition are only small in a relative way because an average firm
with 500 employees in the SOCMI industry has an average sales of over
$180 million.
Of the 66 firms analyzed in the economic impact analysis, only 10
have fewer than 1,000 employees. Since these 10 are only 15 percent of
the firms analyzed, they do not constitute a substantial number
(usually 20 percent).
The economic analysis also projected generally small impacts (87
percent of the analyzed sample are projected to have output changes of
less than 2 percent). Therefore, the standard is not expected to have a
significant economic impact on a substantial number of small firms.
Pursuant to the provisions of 5 U.S.C. 605(b), I hereby certify
that this rule will not have a significant economic impact on a
substantial number of small business entities.
E. Review
This regulation will be reviewed 9 years from the date of
promulgation. This review will include an assessment of such factors as
evaluation of the residual health risks, any overlap with other
programs, the existence of alternative methods, enforceability,
improvements in emission control technology and health data, and the
recordkeeping and reporting requirements.
Table 1.--National Primary Air Pollution Impacts in the Fifth Yeara
----------------------------------------------------------------------------------------------------------------
Baseline emissions (Mg/ Emission reductions
yr) ---------------------------------------
Emission points -------------------------- (Mg/yr) Percent
---------------------------------------
HAP VOCb HAP VOCb HAP VOCb
----------------------------------------------------------------------------------------------------------------
Equipment leaks............................... 62,000 79,000 54,000 69,000 87 87
Process vents................................. 310,000 600,000 300,000 500,000 97 83
Storage vesselsc.............................. 14,000 14,000 7,300 7,300 52 52
Wastewater collection and treatment operations 130,000 490,000 100,000 370,000 77 76
Transfer loading operations................... 900 900 500 500 56 56
-----------------------------------------------------------------
Totalc.................................... 520,000 1,200,000 460,000 950,000 88 79
----------------------------------------------------------------------------------------------------------------
aThese numbers represent estimated values for the fifth year. Existing emission points contribute 84 percent of
the total emission reduction. Emission points associated with chemical manufacturing process equipment built
in the first 5 years of the standard contribute 16 percent of the total emission reduction.
bThe VOC estimates consist of the sum of the HAP estimates and the non-HAP VOC estimates.
cAs discussed in section III.B.3 of the preamble, the EPA has deferred the final decision regarding control of
medium-sized storage vessels at existing sources. Therefore, the emission reductions for storage vessels shown
above, and consequently for the total, may be slightly overstated.
Table 2.--National CO and NOx Emissions Impacts in the Fifth Year
------------------------------------------------------------------------
Increase in CO Increase in
Emission points emissionsa (Mg/ NOx emissionsa
yr) (Mg/yr)
------------------------------------------------------------------------
Equipment leaks......................... 0 0
Process ventsb.......................... 1,600 16,000
Storage vessels......................... 0 0
Wastewater collection and treatment
operationsc............................ 100 800
Transfer loading operationsb............ d d
-------------------------------
Total............................... 1,700 17,000
------------------------------------------------------------------------
aEmissions of these criteria pollutants are caused by operation of
control devices.
bEmissions result from the combustion of natural gas along with the
organic HAP emission streams in incinerators and flares.
cEmissions result from the combustion of various fossil fuels to
generate steam for use in a steam stripper.
dEmissions are less than 5 Mg/yr.
Table 3.--National Energy Impacts In The Fifth Year
--------------------------------------------------------------------------------------------------------------------------------------------------------
Increase in electricity Increase in Natural gas Increase in steam Totald
consumptiona consumptionb consumptionb,c -------------------------
Emission points ------------------------------------------------------------------------------
106 kw-hr/ 103 BOE/yr TJ
yr 103 BOE/yr 109 Btu/yr 103 BOE/yr 109 Btu/yr 103 BOE/yr
--------------------------------------------------------------------------------------------------------------------------------------------------------
Equipment leaks................................. 0 0 0 0 0 0 0 0
Process vents................................... 260 430 6,900 1,100 0 0 1,500 9,600
Storage vesselse................................ 16 26 0 0 0 0 26 170
Wastewater collection and treatment............. 13 21 3 0.5 3,000 500 520 3,300
Transfer loading operations..................... f 0 45 7 0 0 7 45
-------------------------------------------------------------------------------------------------------
Totale...................................... 290 480 6,900 1,100 3,000 500 2,100 13,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
aConversion to BOE assumed a power plant heat rate of 10,000 Btu/kw-hr, heating value for oil of 144,400 Btu/gal, and 42 gal/bbl.
bConversion to BOE assumed a heating value for oil of 144,400 Btu/gal and 42 gal/bbl.
cSteam use is calculated by multiplying the total volume of wastewater (lpm) from new and existing sources by the steam to feed ratio in the steam
stripper (0.04) and assuming the steam stripper operates 351 days per year. It is assumed that the latent heat of the steam is 1131 Btu/lb and the
boiler has an efficiency of 80 percent (Memorandum from Kristine Pelt, Radian Corporation, to Mary Tom Kissell, EPA/SDB, ``Secondary Environmental
Impact Factors used in the Framework for Steam Stirpping Wastewater.'' February 1, 1994.)
dDue to rounding, column totals may be slightly different.
eAs discussed in section III.B.3 of this preamble, the EPA has deferred the final decision regarding control of medium-sized storage vessels at existing
sources. Therefore, the energy impacts for storage vessels, and consequently for the total, may be slightly overstated.
fElectricity usage is less than 1 * 10\6\ kw-hr/yr.
Table 4.--National Control Cost Impacts In The Fifth Year
----------------------------------------------------------------------------------------------------------------
Total Average HAP Average VOC
capital Total annual cost cost
Emission points costs (106 costs (106 $/ effectivenessa effectivenessa
$) yr) ($/Mg HAP) ($/Mg VOC)
----------------------------------------------------------------------------------------------------------------
Equipment leaks...................................... 120 (0.26) (5) (4)
Process vents........................................ 100 86 290 170
Storage vesselsb..................................... 77 20 2,800 2,800
Wastewater collection and treatment operations....... 140 50 490 130
Transfer loading operations.......................... 12 5 10,000 10,000
----------------------------------------------------------
Totalb, c........................................ 450 160 350 170
----------------------------------------------------------------------------------------------------------------
aAverage cost-effectiveness values are determined by dividing total annual costs by total annual emissions
reduction.
bAs discussed in section III.B.3 of the preamble, the EPA has deferred the final decision regarding control of
medium-sized storage vessels at existing sources. Therefore, the cost impacts associated with storage vessels,
and consequently the total, may be slightly overstated.
cExcept for the Total Capital Costs column, the total figures do not include an element for equipment leaks
because the analysis of equipment leak requirements indicated a cost savings.
Table 5.--Summary of Characteristics of Emission Points Subject to
Proposed Subpart G
------------------------------------------------------------------------
Emission point For existing sources For new sources
------------------------------------------------------------------------
Process vents.......... Vent streams from Vent streams from
continuous (non-batch) continuous (non-
process that:. batch) process that:
(1) contain 50 ppmw HAP's and eq>50 ppmw HAP's and
(2) have a flowrate 0.005 scmm and 0.005 scmm
and
(3) have a cost (3) have a cost
effectiveness $2,000/Mg eq>$11,000/Mg.
Storage tanksa......... Storage vessels having: Storage vessels
(1) a capacity 75 m\3\ and <151 (1)="" a="" capacity="">38 m\3\ and <151 pressure="">13.1 kilopascal; or pressure 13.1 kilopascal;
eq>151 m\3\ with a or
vapor pressure 5.2 kilopascal eq>151 m\3\ with a
vapor pressure 0.7
kilopascal.
Transfer operations.... Transfer racks that Same as existing
load 0.65 source.
million liters of HAP-
containing liquids
with a vapor pressure
10.3
kilopascal.
Wastewater treatment Wastewater streams Wastewater streams
operationsb. that: that:
(1) contain a total (1) have a flowrate
VOHAP concentration of 10 lpm and
table 9 HAP's of 10,000 ppmw; or concentration of
(2) have a flowrate 10 lpm and thn-eq>1,000 ppmw; or
contain a total VOHAP (2) have a flowrate
concentration of table 0.02 lpm
9 HAP's of 1,000 ppmw concentration of any
table 8 HAP 10 ppmw.
------------------------------------------------------------------------
aAs discussed in section III.B.3 of the preamble, the EPA has deferred
the final decision regarding control of medium-sized storage vessels
(i.e., 76 m\3\ and <151 m\3\).="" the="" applicability="" criteria="" specified="" in="" this="" table="" represent="" option="" 1="" in="" table="" 6.="">bWastewater treatment operations are exempt if the total source mass HAP
flow rate from all of these streams, determined prior to exposure to
the atmosphere and prior to treatment, is less than 1 metric ton per
year.
Table 6.--Control Alternatives for Existing Sources Subject to Subpart Ga
----------------------------------------------------------------------------------------------------------------
Emission Percent
Kind of emission point Control reduction emission Cost $1,000/ Avg. $/Mg Inc. $/Mg
option Mg/yr reduction yr
----------------------------------------------------------------------------------------------------------------
Process ventsb.................... 1 235,000 93 55,000 234 ...........
2 236,000 93 58,000 245 1,800
3 238,000 94 62,000 260 2,500
4 239,000 94 66,000 276 3,900
5 241,000 95 97,000 404 23,000
Wastewaterc....................... 0 0 0 0 0 ...........
1 68,400 79 29,200 430 430
2 69,100 80 32,100 470 4,300
3 69,600 81 39,100 560 13,000
4 73,100 85 123,000 1,700 24,000
Transferd......................... 1 360 65 3,100 8,700 ...........
2 420 77 6,500 15,000 54,000
Storage: Smalle................... 1 0 0 0 0 ...........
2 380 95 22,000 58,000 58,000
Storage: Mediumf,g................ 1 370 72 2,400 6,600 ...........
2 450 88 6,400 14,200 48,000
Storage: Largeh................... 1 2,000 19 5,300 2,600 ...........
2 5,100 48 10,300 2,000 1,600
3 8,900 84 25,300 2,800 3,900
4 9,000 84 27,100 3,000 122,000
Totali: Floorg................ ........... 238,000 68 66,000 280 ...........
Selected optiong............ ........... 312,000 89 107,000 340 550
Total controlg.............. ........... 324,000 92 282,000 870 14,600
----------------------------------------------------------------------------------------------------------------
aThe impacts in this table are based on well-characterized chemical manufacturing processes and were estimated
using the model emission point approach described in Section V of the proposal (57 FR 62621-62622).
bProcess vent options are:
1TRE = $1,500/Mg
2TRE = $2,000/Mg
3TRE = $3,000/Mg
4TRE = $5,000/Mg
5Control of all process vents.
cWastewater options are:
110 lpm and 1,000 ppm
25 lpm and 800 ppm
31 lpm and 500 ppm
4Control of all wastewater streams.
dTransfer options are:
10.65 million liter and 10.3 kilopascal
2Control of all transfer racks.
eSmall denotes storage vessels with capacity greater than or equal to 38 m3 (10,000 gal), but less than 75 m3
(20,000 gal). Option 1 is no control; and option 2 is control of all storage vessels.
fMedium denotes storage vessels with capacity greater than or equal to 75 m3 (20,000 gal), but less than 151 m3
(40,000 gal). Option 1 is 1.9 psia; and option 2 is control of all storage vessels.
gAs discussed in section III.B.3 of the preamble, the EPA has deferred the final decision regarding control of
medium-sized storage vessels at existing sources. Therefore, figures for emission reduction and cost may be
slightly overstated for storage vessels, and consequently for the totals.
hLarge denotes storage vessels with capacity greater than or equal to 151 m3 (40,000 gal). Option 1 is 1.9 psia;
option 2 is 0.75 psia; and option 3 is control of all storage vessels.
iThese totals do not include control impacts for equipment leaks. The floor is represented by the first option
for each emission point, except storage.
Table 7.--Control Alternatives for New Sources Subject to Subpart Ga,b
----------------------------------------------------------------------------------------------------------------
Emission Percent
Kind of emission point Control reduction emission Cost $1,000/ Avg. $/Mg Inc. $/Mg
option Mg/yr reduction yr
----------------------------------------------------------------------------------------------------------------
Process Ventsc.................... 1 46,000 95 14,000 300 ...........
2 46,000 95 18,000 400 47,000
Wastewaterd....................... 1 10,300 63 10,000 975 ...........
2 13,500 82 12,800 948 860
3 13,900 85 23,500 1,690 28,000
Transfere......................... 1 68 65 590 8,700 ...........
2 80 77 1,200 15,000 54,000
Storage........................... 1 64 86 1,800 28,400 ...........
Smallf............................ 2 71 95 4,100 58,100 336,000
Storage........................... 1 70 72 450 6,400 ...........
Mediumg........................... 2 86 88 1,200 13,800 47,000
Storage........................... 1 970 48 1,600 1,600 ...........
Largeh............................ 2 1,700 84 2,900 1,700 1,900
3 1,700 84 3,200 1,900 89,000
Totali: floor................. ........... 57,500 86 28,400 490 ...........
Selected option............. ........... 61,400 92 32,500 530 1,100
Total control............... ........... 61,800 92 51,200 830 46,800
----------------------------------------------------------------------------------------------------------------
aThe impacts in this table are based on well-characterized chemical manufacturing processes and were estimated
using the model emission point approach described in Section V of the proposal (57 FR 62621--62622).
bEstimated control impacts for fifth year after promulgation of the HON based on an assumed industry growth of
3.5 percent each year.
cProcess vents options are:
1TRE = $11,000/Mg
2control of all process vents
dWastewater options are:
110 ppmw
20.02 lpm and 10 ppmw
3control of all wastewater streams
eNew and existing transfer options are the same.
fSmall denotes storage vessels with capacity greater than or equal to 38 m\3\ (10,000 gal), but less than 75
m\3\ (20,000 gal). Option 1 is 1.9 psia; and option 2 is control of all storage vessels.
gMedium denotes storage vessels with capacity greater than or equal to 75 m\3\ (20,000 gal), but less than 151
m\3\ (40,000 gal). Option 1 is 1.9 psia; and option 2 is control of all storage vessels.
hLarge denotes storage vessels with capacity greater than or equal to 151 m\3\ (40,000 gal). Option 1 is 0.75
psia; option 2 is 0.10 psia; and option 2 is control of all storage vessels.
iThese totals do not include control impacts for equipment leaks. The floor is represented by option 1 for each
emission point.
List of Subjects in 40 CFR Part 63
Environmental protection, Air pollution control, Hazardous
substances, Incorporation by reference, Reporting and recordkeeping
requirements.
Dated: February 28, 1994.
Carol M. Browner,
The Administrator.
For the reasons set out in the preamble, title 40, chapter I, part
63 of the Code of Federal Regulations is amended as follows:
PART 63--NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS
FOR SOURCE CATEGORIES
1. The authority citation for part 63 continues to read as follows:
Authority: Sections 101, 112, 114, 116, and 301 of the Clean Air
Act (42 U.S.C. 7401, et seq., as amended by Pub. L. 101-549, 104
Stat. 2399).
2. Section 63.14 is amended by adding paragraphs (b)(3) and (c) to
read as follows:
Sec. 63.14 Incorporation by reference.
* * * * *
(b) * * *
(3) ASTM D2879-83, Standard Test Method for Vapor Pressure--
Temperature Relationship and Initial Decomposition Temperature of
Liquids by Isoteniscope, IBR approved for Sec. 63.111 of subpart G of
this part.
(c) The materials listed below are available for purchase from the
American Petroleum Institute (API), 1220 L Street, NW., Washington, DC
20005.
(1) API Publication 2517, Evaporative Loss from External Floating-
Roof Tanks, Third Edition, February 1989, IBR approved for Sec. 63.111
of subpart G of this part.
(2) API Publication 2518, Evaporative Loss from Fixed-roof Tanks,
Second Edition, October 1991, IBR approved for Sec. 63.150(g)(3)(i)(C)
of subpart G of this part.
3. Part 63 is amended by adding subparts F, G, H, and I, and adding
and reserving subparts J and K to read as follows:
Subpart F--National Emission Standards for Organic Hazardous Air
Pollutants From the Synthetic Organic Chemical Manufacturing Industry
Secs.
63.100 Applicability and designation of source.
63.101 Definitions.
63.102 General standards.
63.103 General compliance, reporting, and recordkeeping provisions.
63.104 Heat exchange system requirements.
63.105 Maintenance wastewater requirements.
63.106 Delegation of authority.
Table 1 to Subpart F--Synthetic Organic Chemical Manufacturing Industry
Chemicals
Table 2 to Subpart F--Organic Hazardous Air Pollutants
Table 3 to Subpart F--General Provisions Applicable to Supbarts F, G,
and H
Subpart G--National Emission Standards for Organic Hazardous Air
Pollutants From Synthetic Organic Chemical Manufacturing Industry
Process Vents, Storage Vessels, Transfer Operations, and Wastewater
Secs.
63.110 Applicability.
63.111 Definitions.
63.112 Emission standard.
63.113 Process vent provisions--reference control technology.
63.114 Process vent provisions--monitoring requirements.
63.115 Process vent provisions--methods and procedures for process
vent group determination.
63.116 Process vent provisions--performance test methods and
procedures to determine compliance.
63.117 Process vent provisions--reporting and recordkeeping
requirements for group and TRE determinations and performance tests.
63.118 Process vent provisions--periodic reporting and
recordkeeping requirements.
63.119 Storage vessel provisions--reference control technology.
63.120 Storage vessel provisions--procedures to determine
compliance.
63.121 Storage vessel provisions--alternative means of emission
limitation.
63.122 Storage vessel provisions--reporting.
63.123 Storage vessel provisions--recordkeeping.
63.124 [Reserved]
63.125 [Reserved]
63.126 Transfer operations provisions--reference control
technology.
63.127 Transfer operations provisions--monitoring requirements.
63.128 Transfer operations provisions--test methods and procedures.
63.129 Transfer operations provisions--reporting and recordkeeping
for performance tests and notification of compliance status.
63.130 Transfer operations provisions--periodic reporting and
recordkeeping.
63.131 Process wastewater provisions--flow diagrams and tables.
63.132 Process wastewater provisions--general.
63.133 Process wastewater provisions--wastewater tanks.
63.134 Process wastewater provisions--surface impoundments.
63.135 Process wastewater provisions--containers.
63.136 Process wastewater provisions--individual drain systems.
63.137 Process wastewater provisions--oil-water separators.
63.138 Process wastewater provisions--treatment processes.
63.139 Process wastewater provisions--control devices.
63.140 Process wastewater provisions--delay of repair.
63.141 [Reserved]
63.142 [Reserved]
63.143 Process wastewater provisions--inspections and monitoring of
operations.
63.144 Process wastewater provisions--test methods and procedures
for applicability and Group 1/Group 2 determination.
63.145 Process wastewater provisions--test methods and procedures
to determine compliance.
63.146 Process wastewater provisions--reporting.
63.147 Process wastewater provisions--recordkeeping.
63.148 Leak inspection provisions.
63.149 [Reserved]
63.150 Emissions averaging provisions.
63.151 Initial notification and implementation plan.
63.152 General reporting and continuous records.
Appendix to Subpart G--Tables and Figures
Subpart H--National Emission Standards for Organic Hazardous Air
Pollutants for Equipment Leaks
Secs.
63.160 Applicability and designation of source.
63.161 Definitions.
63.162 Standards: General.
63.163 Standards: Pumps in light liquid service.
63.164 Standards: Compressors.
63.165 Standards: Pressure relief devices in gas/vapor service.
63.166 Standards: Sampling connection systems.
63.167 Standards: Open-ended valves or lines.
63.168 Standards: Valves in gas/vapor service and in light liquid
service.
63.169 Standards: Pumps, valves, connectors, and agitators in heavy
liquid service; instrumentation systems; and pressure relief devices
in liquid service.
63.170 Standards: Surge control vessels and bottoms receivers.
63.171 Standards: Delay of repair.
63.172 Standards: Closed-vent systems and control devices.
63.173 Standards: Agitators in gas/vapor service and in light
liquid service.
63.174 Standards: Connectors in gas/vapor service and in light
liquid service.
63.175 Quality improvement program for valves.
63.176 Quality improvement program for pumps.
63.177 Alternative means of emission limitation: General.
63.178 Alternative means of emission limitation: Batch processes.
63.179 Alternative means of emission limitation: Enclosed-vented
process units.
63.180 Test methods and procedures.
63.181 Recordkeeping requirements.
63.182 Reporting requirements.
Table 1 to Subpart H--Batch Processes
Subpart I--National Emission Standards for Organic Hazardous Air
Pollutants for Certain Processes Subject to the Negotiated Regulation
for Equipment Leaks
63.190 Applicability and designation of source.
63.191 Definitions.
63.192 Standard.
63.193 Delegation of authority.
Subpart J--[Reserved]
Subpart K--[Reserved]
Subpart F--National Emission Standards for Organic Hazardous Air
Pollutants from the Synthetic Organic Chemical Manufacturing
Industry.
Sec. 63.100 Applicability and designation of source.
(a) This subpart provides applicability provisions, definitions,
and other general provisions that are applicable to subparts G and H of
this part.
(b) Except as provided in paragraph (c) of this section, the
provisions of subparts F, G, and H of this part apply to chemical
manufacturing process units that meet all the criteria specified in
paragraphs (b)(1), (b)(2), and (b)(3) of this section:
(1) Manufacture as a primary product one or more of the chemicals
listed in table 1 of this subpart;
(2) Use as a reactant or manufacture as a product, by-product, or
co-product, one or more of the organic hazardous air pollutants listed
in table 2 of this subpart; and
(3) Are located at a plant site that is a major source as defined
in section 112(a) of the Act.
(c) The owner or operator of a chemical manufacturing process unit
that meets the criteria specified in paragraphs (b)(1) and (b)(3) of
this section but does not use as a reactant or manufacture as a
product, by-product, or co-product any organic hazardous air pollutant
listed in table 2 of this subpart shall comply only with the
requirements of Sec. 63.103(e) of this subpart. To comply with this
subpart, such chemical manufacturing process units shall not be
required to comply with the provisions of subpart A of this part.
(d) The primary product of a chemical manufacturing process unit
shall be determined according to the procedures specified in paragraphs
(d)(1), (d)(2), and (d)(3) of this section.
(1) If a chemical manufacturing process unit produces more than one
intended chemical product, the product with the greatest annual design
capacity on a mass basis determines the primary product of the process.
(2) If a chemical manufacturing process unit has two or more
products that have the same maximum annual design capacity on a mass
basis and if one of those chemicals is listed in table 1 of this
subpart, then the listed chemical is considered the primary product and
the chemical manufacturing process unit is subject to this subpart. If
more than one of the products is listed in table 1 of this subpart,
then the owner or operator may designate as the primary product any of
the listed chemicals and the chemical manufacturing process unit is
subject to this subpart.
(3) For chemical manufacturing process units that are designed and
operated as flexible operation units, the primary product shall be
determined for existing sources based on the expected utilization for
the five years following April 22, 1994 and for new sources based on
the expected utilization for the first five years after initial start-
up.
(i) If the predominant use of the flexible operation unit, as
described in paragraphs (d)(3)(i)(A) and (d)(3)(i)(B) of this section,
is to produce one or more chemicals listed in table 1 of this subpart,
then the flexible operation unit shall be subject to the provisions of
subparts F, G, and H of this part.
(A) If the flexible operation unit produces one product for the
greatest annual operating time, then that product shall represent the
primary product of the flexible operation unit.
(B) If the flexible operation unit produces multiple chemicals
equally based on operating time, then the product with the greatest
annual production on a mass basis shall represent the primary product
of the flexible operation unit.
(ii) The determination of applicability of this subpart to chemical
manufacturing process units that are designed and operated as flexible
operation units shall be reported in the Implementation Plan required
by Sec. 63.151 (c), (d), and (e) of subpart G of this part or as part
of an operating permit application.
(e) The source to which this subpart applies is the collection of
the process vents; storage vessels; transfer racks; wastewater and the
associated treatment residuals; and pumps, compressors, agitators,
pressure relief devices, sampling connection systems, open-ended valves
or lines, valves, connectors, instrumentation systems, surge control
vessels, and bottoms receivers that are associated with the chemical
manufacturing process units that meet the criteria specified in
paragraphs (b)(1) through (b)(3) of this section.
(1) Subparts F and G of this part apply to emissions from process
vents, storage vessels, transfer racks, and wastewater streams and
associated treatment residuals within a source that is subject to this
subpart.
(2) Subparts F and H of this part apply to emissions from pumps,
compressors, agitators, pressure relief devices, sampling connection
systems, open-ended valves or lines, valves, connectors,
instrumentation systems, surge control vessels, and bottoms receivers,
within a source that is subject to this subpart.
(f) The source does not include the emission points listed in
paragraphs (f)(1) through (f)(9) of this section. This subpart does not
require emission points that are not included in the source to comply
with the provisions of subpart A of this part.
(1) Vents from chemical manufacturing process units that are
designed and operated as batch operations;
(2) Stormwater from segregated sewers;
(3) Water from fire-fighting and deluge systems in segregated
sewers;
(4) Spills;
(5) Water from safety showers;
(6) Vessels storing organic liquids that contain organic hazardous
air pollutants only as impurities;
(7) Loading racks, loading arms, or loading hoses that only
transfer liquids containing organic hazardous air pollutants as
impurities;
(8) Loading racks, loading arms, or loading hoses that vapor
balance during all loading operations; and
(9) Equipment that is intended to operate in organic hazardous air
pollutant service, as defined in Sec. 63.161 of subpart H of this part,
for less than 300 hours during the calendar year.
(g) The owner or operator shall follow the procedures specified in
paragraphs (g)(1) and (g)(2) of this section to determine whether a
storage vessel is part of the source to which this subpart applies.
(1) Where a storage vessel is used exclusively by a chemical
manufacturing process unit, the storage vessel shall be considered part
of that chemical manufacturing process unit.
(i) If the chemical manufacturing process unit is subject to this
subpart according to the criteria specified in paragraph (b) of this
section, then the storage vessel is part of the source to which this
subpart applies.
(ii) If the chemical manufacturing process unit is not subject to
this subpart according to the criteria specified in paragraph (b) of
this section, then the storage vessel is not part of the source to
which this subpart applies.
(2) If a storage vessel is not dedicated to a single chemical
manufacturing process unit, then the applicability of subparts F and G
of this part shall be determined according to the provisions in
paragraphs (g)(2)(i) through (g)(2)(iv) of this section.
(i) If a storage vessel is shared among chemical manufacturing
process units and one of the process units has the predominant use, as
determined by paragraph (g)(2)(i)(A) and (g)(2)(i)(B) of this section,
then the storage vessel is part of that chemical manufacturing process
unit.
(A) If the greatest input into the storage vessel is from a
chemical manufacturing process unit that is located on the same plant
site, then that chemical manufacturing process unit has the predominant
use.
(B) If the greatest input into the storage vessel is provided from
a chemical manufacturing process unit that is not located on the same
plant site, then the predominant use is the chemical manufacturing
process unit on the same plant site that receives the greatest amount
of material from the storage vessel.
(ii) If a storage vessel is shared among chemical manufacturing
process units so that there is no single predominant use, and at least
one of those chemical manufacturing process units is subject to this
subpart, the storage vessel shall be considered to be part of the
chemical manufacturing process unit that is subject to this subpart. If
more than one chemical manufacturing process unit is subject to this
subpart, the owner or operator may assign the storage vessel to any of
the chemical manufacturing process units subject to this subpart.
(iii) If the predominant use of a storage vessel varies from year
to year, then the applicability of this subpart shall be determined
based on the utilization that occurred during the year preceding April
22, 1994. This determination shall be reported in the Implementation
Plan required by Sec. 63.151(c), (d), and (e) of subpart G of this part
or as part of an operating permit application.
(iv) If there is a change in the material stored in the storage
vessel, the owner or operator shall reevaluate the applicability of
this subpart to the vessel.
(h) The owner or operator shall follow the procedures specified in
paragraphs (h)(1) and (h)(2) of this section to determine whether the
arms and hoses in a loading rack are part of the source to which this
subpart applies.
(1) Where a loading rack is used exclusively by a chemical
manufacturing process unit, the loading rack shall be considered part
of that specific chemical manufacturing process unit.
(i) If the chemical manufacturing process unit is subject to this
subpart according to the criteria specified in paragraph (b) of this
section and the loading rack does not meet the criteria specified in
paragraphs (f)(7) and (f)(8) of this section, then the loading rack is
considered a transfer rack (as defined in Sec. 63.101 of this subpart)
and is part of the source to which this subpart applies.
(ii) If the chemical manufacturing process unit is not subject to
this subpart according to the criteria specified in paragraph (b) of
this section, then the loading rack is not considered a transfer rack
(as defined in Sec. 63.101 of this subpart) and is not a part of the
source to which this subpart applies.
(2) If a loading rack is shared among chemical manufacturing
process units, then the applicability of subparts F and G of this part
shall be determined at each loading arm or loading hose according to
the provisions in paragraphs (h)(2)(i) through (h)(2)(v) of this
section.
(i) Each loading arm or loading hose that is dedicated to the
transfer of liquid organic hazardous air pollutants listed in table 2
of this subpart from a chemical manufacturing process unit to which
this subpart applies is part of that chemical manufacturing process
unit and is part of the source to which this subpart applies unless the
loading arm or loading hose meets the criteria specified in paragraph
(f)(7) or (f)(8) of this section.
(ii) If a loading arm or loading hose is shared among chemical
manufacturing process units, and one of the chemical manufacturing
process units provides the greatest amount of the material that is
loaded by the loading arm or loading hose, then the loading arm or
loading hose is part of that chemical manufacturing process unit.
(A) If the chemical manufacturing process unit is subject to this
subpart according to the criteria specified in paragraph (b) of this
section, then the loading arm or loading hose is part of the source to
which this subpart applies unless the loading arm or loading hose meets
the criteria specified in paragraph (f)(7) or (f)(8) of this section.
(B) If the chemical manufacturing process unit is not subject to
this subpart according to the criteria specified in paragraph (b) of
this section, then the loading arm or loading hose is not part of the
source to which this subpart applies.
(iii) If a loading arm or loading hose is shared among chemical
manufacturing process units so that there is no single predominant use
as described in paragraph (h)(2)(ii) of this section and at least one
of those chemical manufacturing process units is subject to this
subpart, then the loading arm or hose is part of the chemical
manufacturing process unit that is subject to this subpart. If more
than one of the chemical manufacturing process units is subject to this
subpart, the owner or operator may assign the loading arm or loading
hose to any of the chemical manufacturing process units subject to this
subpart.
(iv) If the predominant use of a loading arm or loading hose varies
from year to year, then the applicability of this subpart shall be
determined based on the utilization that occurred during the year
preceding April 22, 1994. This determination shall be reported in the
Implementation Plan required by Sec. 63.151 (c), (d), and (e) of
subpart G or as part of an operating permit application.
(v) If there is a change in the material loaded at the loading arm
or loading hose, the owner or operator shall reevaluate the
applicability of this subpart to the loading arm or loading hose.
(i) Except as provided in paragraph (i)(6) of this section, the
owner or operator shall follow the procedures specified in paragraphs
(i)(1) through (i)(5) of this section to determine whether the vent(s)
from a distillation unit is part of the source to which this subpart
applies.
(1) If the greatest input to the distillation unit is from a
chemical manufacturing process unit located on the same plant site,
then the distillation unit shall be assigned to that chemical
manufacturing process unit.
(2) If the greatest input to the distillation unit is provided from
a chemical manufacturing process unit that is not located on the same
plant site, then the distillation unit shall be assigned to the
chemical manufacturing process unit located at the same plant site that
receives the greatest amount of material from the distillation unit.
(3) If a distillation unit is shared among chemical manufacturing
process units so that there is no single predominant use, as described
in paragraphs (i)(1) and (i)(2) of this section, and at least one of
those chemical manufacturing process units is subject to this subpart,
the distillation unit shall be assigned to the chemical manufacturing
process unit that is subject to this subpart. If more than one chemical
manufacturing process unit is subject to this subpart, the owner or
operator may assign the distillation unit to any of the chemical
manufacturing process units subject to this rule.
(4) If the chemical manufacturing process unit to which the
distillation unit is assigned is subject to this subpart and the vent
stream contains greater than 0.005 weight percent total organic
hazardous air pollutants, then the vent(s) from the distillation unit
is considered a process vent (as defined in Sec. 63.101 of this
subpart) and is part of the source to which this subpart applies.
(5) If the predominant use of a distillation unit varies from year
to year, then the applicability of this subpart shall be determined
based on the utilization that occurred during the year preceding April
22, 1994. This determination shall be included in the Implementation
Plan required by Sec. 63.151 (c), (d), and (e) of subpart G of this
part or as part of an operating permit application.
(6) If the distillation unit is part of one of the chemical
manufacturing process units listed in paragraphs (i)(6)(i) through
(i)(6)(iii) of this section and the vent stream contains greater than
0.005 weight percent total organic hazardous air pollutants, then the
vents from the distillation unit are considered process vents (as
defined in Sec. 63.101 of this subpart) and are part of the source to
which this subpart applies.
(i) The Aromex unit that produces benzene, toluene, and xylene;
(ii) The unit that produces hexane; or
(iii) The unit that produces cyclohexane.
(j) The provisions of subparts F, G, and H of this part do not
apply to the processes specified in paragraphs (j)(1) through (j)(6) of
this section. Subparts F, G, and H do not require processes specified
in paragraphs (j)(1) through (j)(6) to comply with the provisions of
subpart A of this part.
(1) Research and development facilities, regardless of whether the
facilities are located at the same plant site as a chemical
manufacturing process unit that is subject to the provisions of
subparts F, G, or H of this part.
(2) Petroleum refining process units, regardless of whether the
units supply feedstocks that include chemicals listed in table 1 of
this subpart to chemical manufacturing process units that are subject
to the provisions of subparts F, G, or H of this part.
(3) Ethylene process units, regardless of whether the units supply
feedstocks that include chemicals listed in table 1 of this subpart to
chemical manufacturing process units that are subject to the provisions
of subparts F, G, or H of this part.
(4) Equipment that is located within a chemical manufacturing
process unit that is subject to this subpart but does not contain
organic hazardous air pollutants.
(5) Chemical manufacturing process units that are located in coke
by-product recovery plants.
(6) Solvent reclamation, recovery, or recycling operations at
hazardous waste TSDF facilities requiring a permit under 40 CFR part
270 that are separate entities and not part of a SOCMI chemical
manufacturing process unit.
(k) Except as provided in paragraphs (l) and (m) of this section,
sources subject to subparts F, G, or H of this part are required to
achieve compliance on or before the dates specified in paragraphs
(k)(1), (k)(2), and (k)(3) of this section.
(1) New sources that commence construction or reconstruction after
December 31, 1992 shall be in compliance with subparts F, G, and H of
this part upon initial start-up or April 22, 1994, whichever is later,
as provided in Sec. 63.6(b) of subpart A of this part.
(2) Existing sources shall be in compliance with subparts F and G
of this part no later than 3 years after April 22, 1994, as provided in
Sec. 63.6(c) of subpart A of this part, unless an extension has been
granted by the Administrator as provided in Sec. 63.151(a)(6) of
subpart G of this part or granted by the operating permit authority as
provided in Sec. 63.6(i) of subpart A of this part.
(3) Existing sources shall be in compliance with subpart H of this
part no later than the dates specified in paragraphs (k)(3)(i) through
(k)(3)(v) of this section. The group designation for each process unit
is indicated in table 1 of this subpart.
(i) Group I: October 24, 1994.
(ii) Group II: January 23, 1995.
(iii) Group III: April 24, 1995.
(iv) Group IV: July 24, 1995.
(v) Group V: October 23, 1995.
(l)(1) If an additional chemical manufacturing process unit meeting
the criteria specified in paragraph (b) of this section is added to a
plant site that is a major source as defined in section 112(a) of the
Act, the addition shall be subject to the requirements for a new source
in subparts F, G, and H of this part if:
(i) It is an addition that meets the definition of construction in
Sec. 63.2 of subpart A of this part;
(ii) Such construction commenced after December 31, 1992; and
(iii) The addition has the potential to emit 10 tons per year or
more of any HAP or 25 tons per year or more of any combination of
HAP's, unless the Administrator establishes a lesser quantity.
(2) If any change is made to a chemical manufacturing process unit
subject to this subpart, the change shall be subject to the
requirements of a new source in subparts F, G, and H of this part if:
(i) It is a change that meets the definition of reconstruction in
Sec. 63.2 of subpart A of this part; and
(ii) Such reconstruction commenced after December 31, 1992.
(3) If an additional chemical manufacturing process unit is added
to a plant site or a change is made to a chemical manufacturing process
unit and the addition or change is determined to be subject to the new
source requirements according to paragraph (l)(1) or (l)(2) of this
section:
(i) The new or reconstructed source shall be in compliance with the
new source requirements of subparts F, G, and H of this part upon
initial start-up of the new or reconstructed source or by April 22,
1994, whichever is later; and
(ii) The owner or operator of the new or reconstructed source shall
comply with the reporting and recordkeeping requirements in subparts F,
G, and H of this part that are applicable to new sources. The
applicable reports include, but are not limited to:
(A) The application for approval of construction or reconstruction
which shall be submitted by the date specified in Sec. 63.151(b)(2)(ii)
of subpart G of this part, or an Initial Notification as specified in
Sec. 63.151(b)(2)(iii) of subpart G of this part;
(B) The Implementation Plan and Implementation Plan Updates
required by Sec. 63.151(c) and (j) of subpart G of this part, unless
the information has been submitted in an operating permit application
or amendment;
(C) The Notification of Compliance Status as required by
Sec. 63.152(b) of subpart G of this part for the new or reconstructed
source;
(D) Periodic Reports and Other Reports as required by
Sec. 63.152(c) and (d) of subpart G of this part;
(E) Reports required by Sec. 63.182 of subpart H of this part; and
(F) Reports and notifications required by sections of subpart A of
this part that are applicable to subparts F, G, and H of this part, as
identified in table 3 of this subpart.
(4) If an additional chemical manufacturing process unit is added
to a plant site or if an emission point is added to an existing
chemical manufacturing process unit or if another deliberate
operational process change creating an additional Group 1 emission
point(s) is made to an existing chemical manufacturing process unit,
and if the addition or change is not subject to the new source
requirements as determined according to paragraph (l)(1) or (l)(2) of
this section, the requirements in paragraphs (l)(4)(i) through
(l)(4)(iii) of this section shall apply. Examples of process changes
include, but are not limited to, changes in production capacity,
feedstock type, or catalyst type, or whenever there is replacement,
removal, or addition of recovery equipment. For purposes of this
paragraph and paragraph (m) of this section, process changes do not
include: Process upsets, unintentional temporary process changes, and
changes that are within the equipment configuration and operating
conditions documented in the Notification of Compliance Status required
by Sec. 63.152(b) of subpart G of this part.
(i) The added emission point(s) and any emission point(s) within
the added or changed chemical manufacturing process unit are subject to
the requirements of subparts F, G, and H of this part for an existing
source;
(ii) The added emission point(s) and any emission point(s) within
the added or changed chemical manufacturing process unit shall be in
compliance with subparts F, G, and H of this part by the dates
specified in paragraph (l)(4)(ii) (A) or (B) of this section, as
applicable.
(A) If a chemical manufacturing process unit is added to a plant
site or an emission point(s) is added to an existing chemical
manufacturing process unit, the added emission point(s) shall be in
compliance upon initial start-up of the added chemical manufacturing
process unit or emission point(s) or by 3 years after April 22, 1994,
whichever is later.
(B) If a deliberate operational process change to an existing
chemical manufacturing process unit causes a Group 2 emission point to
become a Group 1 emission point, the owner or operator shall be in
compliance upon initial start-up or by 3 years after April 22, 1994
unless the owner or operator demonstrates to the Administrator that
achieving compliance will take longer than making the change. If this
demonstration is made to the Administrator's satisfaction, the owner or
operator shall follow the procedures in paragraphs (m)(1) through
(m)(3) of this section to establish a compliance date.
(iii) The owner or operator of a chemical manufacturing process
unit or emission point that is added to a plant site and is subject to
the requirements for existing sources shall comply with the reporting
and recordkeeping requirements of subparts F, G, and H of this part
that are applicable to existing sources, including, but not limited to,
the reports listed in paragraphs (l)(4)(iii) (A) through (E) of this
section. A change to an existing chemical manufacturing process unit
shall be subject to the reporting requirements for existing sources
including, but not limited to, the reports listed in paragraphs
(l)(4)(iii) (A) through (E) of this section if the change meets the
criteria specified in Sec. 63.118 (g), (h), (i), or (j) of subpart G of
this part for process vents or the criteria in Sec. 63.151 (i) or (j)
of subpart G of this part for Implementation Plan Updates. The
applicable reports include, but are not limited to:
(A) The Implementation Plan Updates specified in Sec. 63.151 (i)
and (j) of subpart G of this part, unless the information has been
submitted in an operating permit application or amendment;
(B) The Notification of Compliance Status as required by
Sec. 63.152(b) of subpart G of this part for the emission points that
were added or changed;
(C) Periodic Reports and other reports as required by Sec. 63.152
(c) and (d) of subpart G of this part;
(D) Reports required by Sec. 63.182 of subpart H of this part; and
(E) Reports and notifications required by sections of subpart A of
this part that are applicable to subparts F, G, and H of this part, as
identified in table 3 of this subpart.
(m) If a change that does not meet the criteria in paragraph (l)(4)
of this section is made to a chemical manufacturing process unit
subject to subparts F and G of this part, and the change causes a Group
2 emission point to become a Group 1 emission point (as defined in
Sec. 63.111 of subpart G of this part), then the owner or operator
shall comply with the requirements of subpart G of this part for the
Group 1 emission point as expeditiously as practicable, but in no event
later than 3 years after the emission point becomes Group 1.
(1) The owner or operator shall submit to the Administrator for
approval a compliance schedule, along with a justification for the
schedule.
(2) The compliance schedule shall be submitted with the
Implementation Plan update required in Sec. 63.151(i)(2) of subpart G
of this part for emission points included in an emissions average or
Sec. 63.151(j)(1) of subpart G of this part for emission points not in
an emissions average, unless the compliance schedule has been submitted
in an operating permit application or amendment.
(3) The Administrator shall approve the compliance schedule or
request changes within 120 calendar days of receipt of the compliance
schedule and justification.
Sec. 63.101 Definitions.
(a) The following terms as used in subparts F, G, and H of this
part shall have the meaning given them in subpart A of this part: Act,
actual emissions, Administrator, affected source, approved permit
program, commenced, compliance date, construction, continuous
monitoring system, continuous parameter monitoring system, effective
date, emission standard, emissions averaging, EPA, equivalent emission
limitation, existing source, Federally enforceable, fixed capital cost,
hazardous air pollutant, lesser quantity, major source, malfunction,
new source, owner or operator, performance evaluation, performance
test, permit program, permitting authority, reconstruction, relevant
standard, responsible official, run, standard conditions, State, and
stationary source.
(b) All other terms used in this subpart and subparts G and H of
this part shall have the meaning given them in the Act and in this
section. If the same term is defined in subpart A of this part and in
this section, it shall have the meaning given in this section for
purposes of subparts F, G, and H of this part.
Air oxidation reactor means a device or vessel in which air, or a
combination of air and oxygen, is used as an oxygen source in
combination with one or more organic reactants to produce one or more
organic compounds. Air oxidation reactor includes the product separator
and any associated vacuum pump or steam jet.
Batch operation means a noncontinuous operation in which a discrete
quantity or batch of feed is charged into a chemical manufacturing
process unit and distilled or reacted at one time. Batch operation
includes noncontinuous operations in which the equipment is fed
intermittently or discontinuously. Addition of raw material and
withdrawal of product do not occur simultaneously in a batch operation.
After each batch operation, the equipment is generally emptied before a
fresh batch is started.
Bottoms receiver means a tank that collects distillation bottoms
before the stream is sent for storage or for further downstream
processing.
By-product means a chemical that is produced coincidentally during
the production of another chemical.
Chemical manufacturing process unit means the equipment assembled
and connected by pipes or ducts to process raw materials and to
manufacture an intended product. For the purpose of this subpart,
chemical manufacturing process unit includes air oxidation reactors and
their associated product separators and recovery devices; reactors and
their associated product separators and recovery devices; distillation
units and their associated distillate receivers and recovery devices;
associated unit operations (as defined in this section); and any feed,
intermediate and product storage vessels, product transfer racks, and
connected ducts and piping. A chemical manufacturing process unit
includes pumps, compressors, agitators, pressure relief devices,
sampling connection systems, open-ended valves or lines, valves,
connectors, instrumentation systems, and control devices or systems. A
chemical manufacturing process unit is identified by its primary
product.
Control device means any equipment used for recovering or oxidizing
organic hazardous air pollutant vapors. Such equipment includes, but is
not limited to, absorbers, carbon adsorbers, condensers, incinerators,
flares, boilers, and process heaters. For process vents (as defined in
this section), recovery devices are not considered control devices.
Co-product means a chemical that is produced during the production
of another chemical.
Distillate receiver means overhead receivers, overhead
accumulators, reflux drums, and condenser(s) including ejector-
condenser(s) associated with a distillation unit.
Distillation unit means a device or vessel in which one or more
feed streams are separated into two or more exit streams, each exit
stream having component concentrations different from those in the feed
stream(s). The separation is achieved by the redistribution of the
components between the liquid and the vapor phases by vaporization and
condensation as they approach equilibrium within the distillation unit.
Distillation unit includes the distillate receiver, reboiler, and any
associated vacuum pump or steam jet.
Emission point means an individual process vent, storage vessel,
transfer rack, wastewater stream, or equipment leak.
Equipment leak means emissions of organic hazardous air pollutants
from a pump, compressor, agitator, pressure relief device, sampling
connection system, open-ended valve or line, valve, surge control
vessel, bottoms receiver, or instrumentation system in organic
hazardous air pollutant service as defined in Sec. 63.161 of subpart H
of this part.
Ethylene process or ethylene process unit means a chemical
manufacturing process unit in which ethylene and/or propylene are
produced by separation from petroleum refining process streams or by
subjecting hydrocarbons to high temperatures in the presence of steam.
The ethylene process unit includes the separation of ethylene and/or
propylene from associated streams such as a C4 product, pyrolysis
gasoline, and pyrolysis fuel oil. The ethylene process does not include
the manufacture of SOCMI chemicals such as the production of butadiene
from the C4 stream and aromatics from pyrolysis gasoline.
Flexible operation unit means a chemical manufacturing process unit
that manufactures different chemical products periodically by
alternating raw materials or operating conditions. These units are also
referred to as campaign plants or blocked operations.
Heat exchange system means any cooling tower system or once-through
cooling water system (e.g., river or pond water). A heat exchange
system can include more than one heat exchanger and can include an
entire recirculating or once-through cooling system.
Impurity means a substance that is produced coincidentally with the
primary product, or is present in a raw material. An impurity does not
serve a useful purpose in the production or use of the primary product
and is not isolated.
Initial start-up means the first time a new or reconstructed source
begins production, or, for equipment added or changed as described in
Sec. 63.100 (l) or (m) of this subpart, the first time the equipment is
put into operation. Initial start-up does not include operation solely
for testing equipment. For purposes of subpart G of this part, initial
start-up does not include subsequent start-ups (as defined in this
section) of chemical manufacturing process units following malfunctions
or shutdowns or following changes in product for flexible operation
units or following recharging of equipment in batch operation. For
purposes of subpart H of this part, initial start-up does not include
subsequent start-ups (as defined in Sec. 63.161 of subpart H of this
part) of process units (as defined in Sec. 63.161 of subpart H of this
part) following malfunctions or process unit shutdowns.
Loading rack means a single system used to fill tank trucks and
railcars at a single geographic site. Loading equipment and operations
that are physically separate (i.e, do not share common piping, valves,
and other equipment) are considered to be separate loading racks.
Maintenance wastewater means wastewater generated by the draining
of process fluid from components in the chemical manufacturing process
unit into an individual drain system prior to or during maintenance
activities. Maintenance wastewater can be generated during planned and
unplanned shutdowns and during periods not associated with a shutdown.
Examples of activities that can generate maintenance wastewaters
include descaling of heat exchanger tubing bundles, cleaning of
distillation column traps, draining of low legs and high point bleeds,
draining of pumps into an individual drain system, and draining of
portions of the chemical manufacturing process unit for repair.
Operating permit means a permit required by 40 CFR part 70 or 71.
Organic hazardous air pollutant or organic HAP means one of the
chemicals listed in table 2 of this subpart.
Petroleum refining process, also referred to as a petroleum
refining process unit, means a process that for the purpose of
producing transportation fuels (such as gasoline and diesel fuels),
heating fuels (such as fuel gas, distillate, and residual fuel oils),
or lubricants separates petroleum or separates, cracks, or reforms
unfinished derivatives. Examples of such units include, but are not
limited to, alkylation units, catalytic hydrotreating, catalytic
hydrorefining, catalytic hydrocracking, catalytic reforming, catalytic
cracking, crude distillation, and thermal processes.
Plant site means all contiguous or adjoining property that is under
common control, including properties that are separated only by a road
or other public right-of-way. Common control includes properties that
are owned, leased, or operated by the same entity, parent entity,
subsidiary, or any combination thereof.
Process vent means a gas stream containing greater than 0.005
weight percent total organic hazardous air pollutants that is
continuously discharged during operation of the unit from an air
oxidation reactor, other reactor, or distillation unit (as defined in
this section) within a chemical manufacturing process unit that meets
all applicability criteria specified in Sec. 63.100(b)(1) through
(b)(3) of this subpart. Process vents include vents from distillate
receivers, product separators, and ejector-condensers. Process vents
include gas streams that are either discharged directly to the
atmosphere or are discharged to the atmosphere after diversion through
a product recovery device. Process vents exclude relief valve
discharges and leaks from equipment regulated under subpart H of this
part.
Process wastewater means wastewater which, during manufacturing or
processing, comes into direct contact with or results from the
production or use of any raw material, intermediate product, finished
product, by-product, or waste product. Examples are product tank
drawdown or feed tank drawdown; water formed during a chemical reaction
or used as a reactant; water used to wash impurities from organic
products or reactants; water used to cool or quench organic vapor
streams through direct contact; and condensed steam from jet ejector
systems pulling vacuum on vessels containing organics.
Product means a compound or chemical which is manufactured as the
intended product of the chemical manufacturing process unit. By-
products, isolated intermediates, impurities, wastes, and trace
contaminants are not considered products.
Product separator means phase separators, flash drums, knock-out
drums, decanters, degassers, and condenser(s) including ejector-
condenser(s) associated with a reactor or an air oxidation reactor.
Reactor means a device or vessel in which one or more chemicals or
reactants, other than air, are combined or decomposed in such a way
that their molecular structures are altered and one or more new organic
compounds are formed. Reactor includes the product separator and any
associated vacuum pump or steam jet.
Recovery device means an individual unit of equipment capable of
and used for the purpose of recovering chemicals for use, reuse, or
sale. Recovery devices include, but are not limited to, absorbers,
carbon adsorbers, and condensers.
Research and development facility means laboratory and pilot plant
operations whose primary purpose is to conduct research and development
into new processes and products, where the operations are under the
close supervision of technically trained personnel, and is not engaged
in the manufacture of products for commercial sale, except in a de
minimis manner.
Shutdown means the cessation of operation of a chemical
manufacturing process unit or a reactor, air oxidation reactor,
distillation unit, or the emptying and degassing of a storage vessel
for purposes including, but not limited to, periodic maintenance,
replacement of equipment, or repair. Shutdown does not include the
routine rinsing or washing of equipment in batch operation between
batches.
Source means the collection of emission points to which this
subpart applies as determined by the criteria in Sec. 63.100 of this
subpart. For purposes of subparts F, G, and H of this part, the term
affected source as used in subpart A of this part has the same meaning
as the term source defined here.
Start-up means the setting into operation of a chemical
manufacturing process unit for the purpose of production. Start-up does
not include operation solely for testing equipment. Start-up does not
include the recharging of equipment in batch operation. Start-up does
not include changes in product for flexible operation units.
Start-up, shutdown, and malfunction plan means the plan required
under Sec. 63.6(e)(3) of subpart A of this part. This plan details the
procedures for operation and maintenance of the source during periods
of start-up, shutdown, and malfunction.
Storage vessel means a tank or other vessel that is used to store
organic liquids that contain one or more of the organic HAP's listed in
table 2 of this subpart and that has been assigned, according to the
procedures in Sec. 63.100(g) of this subpart, to a chemical
manufacturing process unit that is subject to this subpart. Storage
vessel does not include:
(1) Vessels permanently attached to motor vehicles such as trucks,
railcars, barges, or ships;
(2) Pressure vessels designed to operate in excess of 204.9
kilopascals and without emissions to the atmosphere;
(3) Vessels with capacities smaller than 38 cubic meters;
(4) Vessels storing organic liquids that contain organic hazardous
air pollutants only as impurities;
(5) Bottoms receiver tanks;
(6) Surge control vessels; or
(7) Wastewater storage tanks. Wastewater storage tanks are covered
under the wastewater provisions.
Surge control vessel means feed drums, recycle drums, and
intermediate vessels. Surge control vessels serve several purposes
including equalization of load, mixing, recycle, and emergency supply.
Transfer operation means the loading, into a tank truck or railcar,
of organic liquids that contain one or more of the organic hazardous
air pollutants listed in table 2 of this subpart from a transfer rack
(as defined in this section). Transfer operations do not include
loading at an operating pressure greater than 204.9 kilopascals.
Transfer rack means the collection of loading arms and loading
hoses, at a single loading rack, that are assigned to a chemical
manufacturing process unit subject to this subpart according to the
procedures specified in Sec. 63.100(h) of this subpart and are used to
fill tank trucks and railcars with organic liquids that contain one or
more of the organic hazardous air pollutants listed in table 2 of this
subpart. Transfer rack includes the associated pumps, meters, shutoff
valves, relief valves, and other piping and valves. Transfer rack does
not include:
(1) Racks, arms, or hoses that only transfer liquids containing
organic hazardous air pollutants as impurities;
(2) Racks, arms, or hoses that vapor balance during all loading
operations; or
(3) Racks transferring organic liquids that contain organic
hazardous air pollutants only as impurities.
Unit operation means one or more pieces of process equipment used
to make a single change to the physical or chemical characteristics of
one or more process streams. Unit operations include, but are not
limited to, reactors, distillation columns, extraction columns,
absorbers, decanters, dryers, condensers, and filtration equipment.
Vapor balancing system means a piping system that is designed to
collect organic HAP vapors displaced from tank trucks or railcars
during loading; and to route the collected organic HAP vapors to the
storage vessel from which the liquid being loaded originated, or to
compress collected organic HAP vapors and commingle with the raw feed
of a chemical manufacturing process unit.
Wastewater means organic hazardous air pollutant-containing water,
raw material, intermediate, product, by- product, co-product, or waste
material that exits equipment in a chemical manufacturing process unit
that meets all of the criteria specified in Sec. 63.100(b)(1) through
(b)(3) of this subpart; and either:
(1) Contains a total volatile organic hazardous air pollutant
concentration of at least 5 parts per million by weight and has a flow
rate of 0.02 liter per minute or greater; or
(2) Contains a total volatile organic hazardous air pollutant
concentration of at least 10,000 parts per million by weight at any
flow rate.
Wastewater includes process wastewater and maintenance wastewater.
Sec. 63.102 General standards.
(a) Owners and operators of sources subject to this subpart shall
comply with the requirements of subparts G and H of this part.
(1) The provisions set forth in subparts F and G of this part shall
apply at all times except during periods of start-up, malfunction, and
shutdown (as defined in Sec. 63.101 of this subpart). However, if a
start-up, shutdown, or malfunction of one portion of a chemical
manufacturing process unit does not affect the ability of a particular
emission point to comply with the specific provisions to which it is
subject, then that emission point shall still be required to comply
with the applicable provisions of subparts F and G during the start-up,
shutdown, or malfunction. For example, if there is an overpressure in
the reactor area, a storage vessel in the chemical manufacturing
process unit would still be required to be controlled in accordance
with Sec. 63.119 of subpart G of this part. Similarly, the degassing of
a storage vessel would not affect the ability of a process vent to meet
the requirements of Sec. 63.113 of subpart G of this part.
(2) The provisions set forth in subpart H of this part shall apply
at all times except during periods of start-up, malfunction, and
process unit shutdown (as defined in Sec. 63.161 of subpart H of this
part).
(b) If, in the judgment of the Administrator, an alternative means
of emission limitation will achieve a reduction in organic HAP
emissions at least equivalent to the reduction in organic HAP emissions
from that source achieved under any design, equipment, work practice,
or operational standards in subpart G or H of this part, the
Administrator will publish in the Federal Register a notice permitting
the use of the alternative means for purposes of compliance with that
requirement.
(1) The notice may condition the permission on requirements related
to the operation and maintenance of the alternative means.
(2) Any notice under paragraph (b) of this section shall be
published only after public notice and an opportunity for a hearing.
(3) Any person seeking permission to use an alternative means of
compliance under this section shall collect, verify, and submit to the
Administrator information showing that the alternative means achieves
equivalent emission reductions.
(c) Each owner or operator of a source subject to this subpart
shall obtain a permit under 40 CFR part 70 or part 71 from the
appropriate permitting authority.
(1) If EPA has approved a State operating permit program under 40
CFR part 71, the permit shall be obtained from the State authority. If
the State operating permit program has not been approved, the source
shall apply to the EPA regional office pursuant to 40 CFR part 70.
(2) If an operating permit application has not been submitted by
the dates specified in Sec. 63.151(c) of subpart G of this part, the
owner or operator shall submit an Implementation Plan as specified in
Sec. 63.151 (c), (d), and (e) of subpart G of this part.
(d) The requirements in subparts F, G, and H of this part are
Federally enforceable under section 112 of the Act on and after the
dates specified in Sec. 63.100(k) of this subpart.
Sec. 63.103 General compliance, reporting, and recordkeeping
provisions.
(a) Table 3 of this subpart specifies the provisions of subpart A
that apply and those that do not apply to owners and operators of
sources subject to subparts F, G, and H of this part.
(b) Initial performance tests and initial compliance determinations
shall be required only as specified in subparts G and H of this part.
(1) Performance tests and compliance determinations shall be
conducted according to the schedule and procedures in Sec. 63.7(a) of
subpart A of this part and the applicable sections of subparts G and H
of this part.
(2) The owner or operator shall notify the Administrator of the
intention to conduct a performance test at least 30 calendar days
before the performance test is scheduled to allow the Administrator the
opportunity to have an observer present during the test.
(3) Performance tests shall be conducted according to the
provisions of Sec. 63.7(e) of subpart A of this part, except that
performance tests shall be conducted at maximum representative
operating conditions for the process. During the performance test, an
owner or operator may operate the control or recovery device at maximum
or minimum representative operating conditions for monitored control or
recovery device parameters, whichever results in lower emission
reduction.
(4) Data shall be reduced in accordance with the EPA-approved
methods specified in the applicable subpart or, if other test methods
are used, the data and methods shall be validated according to the
protocol in Method 301 of appendix A of this part.
(5) Performance tests may be waived with approval of the
Administrator as specified in Sec. 63.7(h)(2) of subpart A of this
part. Owners or operators of sources subject to subparts F, G, and H of
this part who apply for a waiver of a performance test shall submit the
application by the dates specified in paragraph (b)(5)(i) of this
section rather than the dates specified in Sec. 63.7(h)(3) of subpart A
of this part.
(i) If a request is made for an extension of compliance under
Sec. 63.151(a)(6) of subpart G or Sec. 63.6(i) of subpart A of this
part, the application for a waiver of an initial performance test shall
accompany the information required for the request for an extension of
compliance. If no extension of compliance is requested, the application
for a waiver of an initial performance test shall be submitted no later
than 90 calendar days before the Notification of Compliance Status
required in Sec. 63.152(b) of subpart G of this part is due to be
submitted.
(ii) Any application for a waiver of a performance test shall
include information justifying the owner or operator's request for a
waiver, such as the technical or economic infeasibility, or the
impracticality, of the source performing the required test.
(c) Each owner or operator of a source subject to subparts F, G,
and H of this part shall keep copies of all applicable reports and
records required by subparts F, G, and H of this part for at least 5
years; except that, if subparts G or H require records to be maintained
for a time period different than 5 years, those records shall be
maintained for the time specified in subpart G or H of this part.
(1) All applicable records shall be maintained in such a manner
that they can be readily accessed. The most recent 2 years of records
shall be retained on site at the source or shall be accessible from a
central location by computer. The remaining 3 years of records may be
retained offsite. Records may be maintained in hard copy or computer-
readable form including, but not limited to, on paper, microfilm,
computer, floppy disk, magnetic tape, or microfiche.
(2) The owner or operator subject to subparts F, G, and H of this
part shall keep the records specified in this paragraph, as well as
records specified in subparts G and H.
(i) Records of the occurrence and duration of each start-up,
shutdown, and malfunction of operation of a chemical manufacturing
process unit subject to subparts F, G, or H of this part.
(ii) Records of the occurrence and duration of each malfunction of
air pollution control equipment or continuous monitoring systems used
to comply with subpart F, G, or H of this part.
(iii) For each start-up, shutdown, and malfunction, records that
the procedures specified in the source's start-up, shutdown, and
malfunction plan were followed, and documentation of actions taken that
are not consistent with the plan. For example, if a start-up, shutdown,
and malfunction plan includes procedures for routing a control device
to a backup control device (e.g., the incinerator for a halogenated
stream could be routed to a flare during periods when the primary
control device is out of service), records must be kept of whether the
plan was followed.
(iv) For continuous monitoring systems used to comply with subpart
G, records documenting the completion of calibration checks and
maintenance of continuous monitoring systems that are specified in the
manufacturer's instructions.
(3) Records of start-up, shutdown and malfunction and continuous
monitoring system calibration and maintenance are not required if they
pertain solely to Group 2 emission points, as defined in Sec. 63.111 of
subpart G of this part, that are not included in an emissions average.
(d) All reports required under subparts F, G, and H of this part
shall be sent to the Administrator at the addresses listed in
Sec. 63.13 of subpart A of this part, except that requests for
permission to use an alternative means of compliance as provided for in
Sec. 63.102(b) of this subpart and application for approval of a
nominal efficiency as provided for in Sec. 63.150 (i)(1) through (i)(6)
of subpart G of this part shall be submitted to the Director of the EPA
Office of Air Quality Planning and Standards rather than to the
Administrator or delegated authority.
(1) Wherever subpart A specifies ``postmark'' dates, submittals may
be sent by methods other than the U.S. Mail (e.g., by fax or courier).
(i) Submittals sent by U.S. Mail shall be postmarked on or before
the specified date.
(ii) Submittals sent by other methods shall be received by the
Administrator on or before the specified date.
(2) If acceptable to both the Administrator and the owner or
operator of a source, reports may be submitted on electronic media.
(e) Information, data, and analyses used to determine that a
chemical manufacturing process unit does not use as a reactant or
manufacture as a product any organic hazardous air pollutant shall be
recorded. Examples of information that could document this include, but
are not limited to, records of chemicals purchased for the process,
analyses of process stream composition, engineering calculations, or
process knowledge.
Sec. 63.104 Heat exchange system requirements.
(a) Owners and operators of sources subject to subpart G of this
part shall comply with the requirements specified in paragraphs (b) and
(c) of this section.
(b) For each heat exchange system that cools process equipment or a
process fluid and that is part of a chemical manufacturing process unit
that is subject to the provisions of this subpart, the owner or
operator shall comply with the requirements of paragraphs (b)(1)
through (b)(4) of this section, except as provided in paragraph (c) of
this section.
(1) The cooling water shall be monitored monthly for the first 6
months and quarterly thereafter to detect leaks.
(i) The cooling water shall be monitored for total HAP, total VOC,
or speciated HAP's.
(A) For recirculating heat exchange systems (cooling tower
systems), speciated HAP's or total HAP's includes all HAP's listed in
table 2 of this subpart, except for benzotrichloride (98077),
bis(chloromethyl)ether (542881), maleic anhydride (108316), and methyl
isocyanate (624839).
(B) For once-through heat exchange systems, speciated HAP's or
total HAP's includes all HAP's listed in table 9 of subpart G of this
part.
(C) If monitoring for speciated HAP's, only HAP's that are present
in the process fluid in concentrations greater than 5 percent by weight
are required to be measured in the cooling water.
(ii) The concentration in the cooling water shall be determined
using any EPA-approved method listed in 40 CFR part 136 as long as the
method is sensitive to concentrations as low as 1 ppm and the same
method is used for both entrance and exit samples. Alternative methods
may be used upon approval by the Administrator.
(iii) The samples shall be taken at the entrance and exit of each
heat exchange system.
(A) For recirculating heat exchange systems, the entrance and exit
are the points at which the cooling water enters the cooling tower
after cooling the process fluid and exits the cooling tower prior to
cooling the process fluid.
(B) For once-through heat exchange systems, the entrance and exit
are the points where the cooling water enters and exits the plant site.
(iv) A minimum of three sets of samples shall be taken of the
cooling water at the entrance and exit of the system, for a total of
six samples. The average inlet and outlet concentrations shall then be
calculated.
(v) A leak is detected if a statistically significant difference in
concentration of at least 1 part per million at the 95 percent
confidence level is observed.
(2) If a leak is detected, the owner or operator shall comply with
the requirements in paragraphs (b)(2)(i) and (b)(2)(ii) of this
section, except as provided in paragraph (b)(3) of this section.
(i) The leak shall be repaired as soon as practicable but not later
than 45 calendar days after the owner or operator receives results of
monitoring tests that indicate that a leak is present. Repair of a leak
can include such activities as repairing a leaking heat exchanger or
rerouting the waste from a steam jet ejector.
(ii) Once the leak has been repaired, the owner or operator must
test the heat exchange system using the procedures described in
paragraph (b)(1) of this section to ensure that the leak has been
repaired.
(3) Delay of repair of heat exchange systems for which leaks have
been detected is allowed if either of the conditions in paragraph
(b)(3)(i) or (b)(3)(ii) of this section are met.
(i) If the owner or operator can demonstrate that a shutdown would
cause greater emissions than the emissions from the leaking heat
exchange system until the next planned shutdown, a shutdown is not
required. Repair of this equipment shall occur before the end of the
next shutdown.
(ii) If the equipment is isolated from the process and does not
remain in HAP service.
(4) If an owner or operator invokes the delay of repair provisions
for a heat exchange system, the following information shall be
submitted in the next semi-annual Periodic Report required by
Sec. 63.152(c) of subpart G of this part. If the leak remains
unrepaired, the information shall also be submitted in each subsequent
periodic report, until repair of the leak is reported.
(i) The owner or operator shall report the presence of the leak and
the date that the leak was detected.
(ii) The owner or operator shall report whether or not the leak has
been repaired.
(iii) The owner or operator shall report the reason(s) for delay of
repair. If delay of repair is invoked due to the reasons described in
paragraph (b)(3)(i) of this section, documentation of emissions
estimates must also be submitted.
(iv) If the leak remains unrepaired, the owner or operator shall
report the expected date of repair.
(v) If the leak is repaired, the owner or operator shall report the
date of successful repair of the leak.
(c) An owner or operator is not required to meet the requirements
in paragraphs (b)(1) and (b)(2) of this section if either of the
conditions in paragraph (c)(1) or (c)(2) of this section are met.
(1) The heat exchange system is operated with the minimum pressure
on the cooling water side at least 35 kilopascals greater than the
maximum pressure on the process side.
(2) The once-through heat exchange system currently has an NPDES
permit with an allowable discharge limit of less than 1 ppm.
Sec. 63.105 Maintenance wastewater requirements.
(a) Each owner or operator of a source subject to this subpart
shall comply with the requirements of paragraphs (b) through (e) of
this section for maintenance wastewaters containing those organic HAP's
listed in table 2 of this subpart.
(b) The owner or operator shall prepare a description of
maintenance procedures for management of wastewaters generated from the
emptying and purging of equipment in the process during temporary
shutdowns for inspections, maintenance, and repair (i.e., a
maintenance-turnaround) and during periods which are not shutdowns
(i.e., routine maintenance). The descriptions shall:
(1) Specify the process equipment or maintenance tasks that are
anticipated to create wastewater during maintenance activities.
(2) Specify the procedures that will be followed to properly manage
the wastewater and control organic HAP emissions to the atmosphere; and
(3) Specify the procedures to be followed when clearing materials
from process equipment.
(c) The owner or operator shall modify and update the information
required by paragraph (b) of this section as needed following each
maintenance procedure based on the actions taken and the wastewaters
generated in the preceding maintenance procedure.
(d) The owner or operator shall implement the procedures described
in paragraphs (b) and (c) of this section as part of the start-up,
shutdown, and malfunction plan required under Sec. 63.6(e)(3) of
subpart A of this part.
(e) The owner or operator shall maintain a record of the
information required by paragraphs (b) and (c) of this section as part
of the start-up, shutdown, and malfunction plan required under
Sec. 63.6(e)(3) of subpart A of this part.
Sec. 63.106 Delegation of authority.
(a) In delegating implementation and enforcement authority to a
State under section 112(d) of the Act, the authorities contained in
paragraph (b) of this section shall be retained by the Administrator
and not transferred to a State.
(b) Authorities which will not be delegated to States:
Sec. 63.102(b) of this subpart, Sec. 63.150(i)(1) through (i)(4) of
subpart G of this part, and Sec. 63.177 of subpart H of this part.
Table 1 to Subpart F--Synthetic Organic Chemical Manufacturing Industry
Chemicals
------------------------------------------------------------------------
Chemical namea CAS No.b Group
------------------------------------------------------------------------
Acenaphthene....................................... 83329 V
Acetal............................................. 105577 V
Acetaldehyde....................................... 75070 II
Acetaldol.......................................... 107891 II
Acetamide.......................................... 60355 II
Acetanilide........................................ 103844 II
Acetic acid........................................ 64197 II
Acetic anhydride................................... 108247 II
Acetoacetanilide................................... 102012 III
Acetone............................................ 67641 I
Acetone cyanohydrin................................ 75865 V
Acetonitrile....................................... 75058 I
Acetophenone....................................... 98862 I
Acrolein........................................... 107028 IV
Acrylamide......................................... 79061 I
Acrylic acid....................................... 79107 IV
Acrylonitrile...................................... 107131 I
Adiponitrile....................................... 111693 I
Alizarin........................................... 72480 V
Alkyl anthraquinones............................... 008 V
Allyl alcohol...................................... 107186 I
Allyl chloride..................................... 107051 IV
Allyl cyanide...................................... 109751 IV
Aminophenol sulfonic acid.......................... 0010 V
Aminophenol (p-)................................... 123308 I
Aniline............................................ 62533 I
Aniline hydrochloride.............................. 142041 III
Anisidine (o-)..................................... 90040 II
Anthracene......................................... 120127 V
Anthraquinone...................................... 84651 III
Azobenzene......................................... 103333 I
Benzaldehyde....................................... 100527 III
Benzene............................................ 71432 I
Benzenedisulfonic acid............................. 98486 I
Benzenesulfonic acid............................... 98113 I
Benzil............................................. 134816 III
Benzilic acid...................................... 76937 III
Benzoic acid....................................... 65850 III
Benzoin............................................ 119539 III
Benzonitrile....................................... 100470 III
Benzophenone....................................... 119619 I
Benzotrichloride................................... 98077 III
Benzoyl chloride................................... 98884 III
Benzyl acetate..................................... 140114 III
Benzyl alcohol..................................... 100516 III
Benzyl benzoate.................................... 120514 III
Benzyl chloride.................................... 100447 III
Benzyl dichloride.................................. 98873 III
Biphenyl........................................... 92524 I
Bisphenol A........................................ 80057 III
Bis(Chloromethyl) Ether............................ 542881 I
Bromobenzene....................................... 108861 I
Bromoform.......................................... 75252 V
Bromonaphthalene................................... 27497514 IV
Butadiene (1,3-)................................... 106990 II
Butanediol (1,4-).................................. 110634 I
Butyl acrylate (n-)................................ 141322 V
Butylene glycol (1,3-)............................. 107880 II
Butyrolacetone..................................... 96480 I
Caprolactam........................................ 105602 II
Carbaryl........................................... 63252 V
Carbazole.......................................... 86748 V
Carbon disulfide................................... 75150 IV
Carbon tetrabromide................................ 558134 II
Carbon tetrachloride............................... 56235 I
Carbon tetrafluoride............................... 75730 II
Chloral............................................ 75876 II
Chloroacetic acid.................................. 79118 II
Chloroacetophenone (2-)............................ 532274 I
Chloroaniline (p-)................................. 106478 II
Chlorobenzene...................................... 108907 I
2-Chloro-1,3-butadiene (Chloroprene)............... 126998 II
Chlorodifluoroethane............................... 25497294 V
Chlorodifluoromethane.............................. 75456 I
Chloroform......................................... 67663 I
Chloronaphthalene.................................. 25586430 IV
Chloronitrobenzene 121733 I
(m-).
Chloronitrobenzene 88733 I
(o-).
Chloronitrobenzene 100005 I
(p-).
Chlorophenol (m-).................................. 108430 II
Chlorophenol (o-).................................. 95578 II
Chlorophenol (p-).................................. 106489 II
Chlorotoluene (m-)................................. 108418 III
Chlorotoluene (o-)................................. 95498 III
Chlorotoluene (p-)................................. 106434 III
Chlorotrifluoromethane............................. 75729 II
Chrysene........................................... 218019 V
Cresol and cresylic acid (m-)...................... 108394 III
Cresol and cresylic acid (o-)...................... 95487 III
Cresol and cresylic acid (p-)...................... 106445 III
Cresols and cresylic acids (mixed)................. 1319773 III
Cumene............................................. 98828 I
Cumene hydroperoxide............................... 80159 I
Cyanoacetic acid................................... 372098 II
Cyclohexane........................................ 110827 I
Cyclohexanol....................................... 108930 I
Cyclohexanone...................................... 108941 I
Cyclohexylamine.................................... 108918 III
Cyclooctadienes.................................... 29965977 II
Decahydronaphthalene............................... 91178 IV
Diacetoxy-2-Butene (1,4-).......................... 0012 V
Diaminophenol hydrochloride........................ 137097 V
Dibromomethane..................................... 74953 V
Dichloroaniline (mixed isomers).................... 27134276 I
Dichlorobenzene (p-)............................... 106467 I
Dichlorobenzene (m-)............................... 541731 I
Dichlorobenzene (o-)............................... 95501 I
Dichlorobenzidine 91941 I
(3,3'-).
Dichlorodifluoromethane............................ 75718 I
Dichloroethane (1,2-) (Ethylenedichloride) (EDC)... 107062 I
Dichloroethyl ether (bis(2-chloroethyl)ether)...... 111444 I
Dichloroethylene (1,2-)............................ 540590 II
Dichlorophenol (2,4-).............................. 120832 III
Dichloropropene (1,3-)............................. 542756 II
Dichlorotetrafluoro- 1320372 V
ethane.
Dichloro-1-butene (3,4-)........................... 760236 II
Dichloro-2-butene (1,4-)........................... 764410 V
Diethanolamine (2,2'-Iminodiethanol)............... 111422 I
Diethyl sulfate.................................... 64675 II
Diethylamine....................................... 109897 IV
Diethylaniline (2,6-).............................. 579668 V
Diethylene glycol.................................. 111466 I
Diethylene glycol dibutyl ether.................... 112732 I
Diethylene glycol diethyl ether.................... 112367 I
Diethylene glycol dimethyl ether................... 111966 I
Diethylene glycol monobutyl ether acetate.......... 124174 I
Diethylene glycol monobutyl ether.................. 112345 I
Diethylene glycol monoethyl ether acetate.......... 112152 I
Diethylene glycol monoethyl ether.................. 111900 I
Diethylene glycol monohexyl ether.................. 112594 V
Diethylene glycol monomethyl ether acetate......... 629389 V
Diethylene glycol monomethyl ether................. 111773 I
Dihydroxybenzoic acid (Resorcylic acid)............ 27138574 V
Dimethylbenzidine 119937 II
(3,3'-).
Dimethyl ether..................................... 115106 IV
Dimethylformamide (N,N-)........................... 68122 II
Dimethylhydrazine 57147 II
(1,1-).
Dimethyl sulfate................................... 77781 I
Dimethyl terephthalate............................. 120616 II
Dimethylamine...................................... 124403 IV
Dimethylaminoethanol (2-).......................... 108010 I
Dimethylaniline (N,N).............................. 121697 III
Dinitrobenzenes (NOS)c............................. 25154545 I
Dinitrophenol (2,4-)............................... 51285 III
Dinitrotoluene (2,4-).............................. 121142 III
Dioxane (1,4-) (1,4-Diethyleneoxide)............... 1239 11I
Dioxolane (1,3-)................................... 646060 I
Diphenyl methane................................... 101815 I
Diphenyl oxide..................................... 101848 I
Diphenyl thiourea.................................. 102089 III
Diphenylamine...................................... 122394 III
Dipropylene glycol................................. 110985 I
Di-o-tolyguanidine................................. 97392 III
Dodecandedioic acid................................ 693232 I
Dodecyl benzene (branched)......................... 123013 V
Dodecyl phenol (branched).......................... 121158585 V
Dodecylaniline..................................... 28675174 V
Dodecylbenzene (n-)................................ 121013 I
Dodecylphenol...................................... 27193868 III
Epichlorohydrin (1-chloro-2,3-epoxypropane)........ 106898 I
Ethanolamine....................................... 141435 I
Ethyl acrylate..................................... 140885 II
Ethylbenzene....................................... 100414 I
Ethyl chloride (Chloroethane)...................... 75003 IV
Ethyl chloroacetate................................ 105395 II
Ethylamine......................................... 75047 V
Ethylaniline (N-).................................. 103695 III
Ethylaniline (o-).................................. 578541 III
Ethylcellulose..................................... 9004573 V
Ethylcyanoacetate.................................. 105566 V
Ethylene carbonate................................. 96491 I
Ethylene dibromide (Dibromoethane)................. 106934 I
Ethylene glycol.................................... 107211 I
Ethylene glycol diacetate.......................... 111557 I
Ethylene glycol dibutyl ether...................... 112481 V
Ethylene glycol diethyl ether 629141 I
(1,2-diethoxyethane).
Ethylene glycol 110714 I
dimethyl ether
Ethylene glycol monoacetate........................ 542596 V
Ethylene glycol monobutyl ether 112072 I
acetate.
Ethylene glycol monobutyl ether.................... 111762 I
Ethylene glycol monoethyl ether 111159 I
acetate.
Ethylene glycol monoethyl ether.................... 110805 I
Ethylene glycol monohexyl ether.................... 112254 V
Ethylene glycol monomethyl ether acetate........... 110496 I
Ethylene glycol monomethyl ether................... 109864 I
Ethylene glycol monooctyl ether.................... 002 V
Ethylene glycol monophenyl ether................... 122996 I
Ethylene glycol monopropyl ether................... 2807309 I
Ethylene oxide..................................... 75218 I
Ethylenediamine.................................... 107153 II
Ethylenediamine tetraacetic acid................... 60004 V
Ethylenimine (Aziridine)........................... 151564 II
Ethylhexyl acrylate (2-isomer)..................... 103117 II
Fluoranthene....................................... 206440 V
Formaldehyde....................................... 50000 I
Formamide.......................................... 75127 II
Formic acid........................................ 64186 II
Fumaric acid....................................... 110178 I
Glutaraldehyde..................................... 111308 IV
Glyceraldehyde..................................... 367475 V
Glycerol........................................... 56815 II
Glycerol tri- (polyoxypro- pylene)ether............ 25791962 II
Glycine............................................ 56406 II
Glyoxal............................................ 107222 II
Hexachlorobenzene.................................. 118741 II
Hexachlorobutadiene................................ 87683 II
Hexachloroethane................................... 67721 II
Hexadiene (1,4-)................................... 592450 II
Hexamethylene- 100970 I
tetramine.
Hexane............................................. 110543 V
Hexanetriol (1,2,6-)............................... 106694 IV
Hydroquinone....................................... 123319 I
Hydroxyadipaldehyde................................ 141311 V
Isobutyl acrylate.................................. 106638 V
Isobutylene........................................ 115117 V
Isophorone......................................... 78591 IV
Isophorone nitrile................................. 0017 V
Isophthalic acid................................... 121915 III
Isopropylphenol.................................... 25168063 III
Linear alkylbenzene................................ ____d I
Maleic anhydride................................... 108316 I
Maleic hydrazide................................... 123331 I
Malic acid......................................... 6915157 I
Metanilic acid..................................... 121471 I
Methacrylic acid................................... 79414 V
Methanol........................................... 67561 IV
Methionine......................................... 63683 I
Methyl acetate..................................... 79209 IV
Methyl acrylate.................................... 96333 V
Methyl bromide (Bromomethane)...................... 74839 IV
Methyl chloride (Chloromethane).................... 74873 IV
Methyl ethyl ketone (2-butanone)................... 78933 V
Methyl formate..................................... 107313 II
Methyl hydrazine................................... 60344 IV
Methyl isobutyl carbinol........................... 108112 IV
Methyl isobutyl ketone (Hexone).................... 108101 IV
Methyl isocyanate.................................. 624839 IV
Methyl mercaptan................................... 74931 IV
Methyl methacrylate................................ 80626 IV
Methyl phenyl carbinol............................. 98851 II
Methyl tert-butyl ether............................ 1634044 V
Methylamine........................................ 74895 IV
Methylaniline (N-)................................. 100618 III
Methylcyclohexane.................................. 108872 III
Methylcyclohexanol................................. 25639423 V
Methylcyclohexanone................................ 1331222 III
Methylene chloride (Dichloromethane)............... 75092 I
Methylene dianiline (4,4'-isomer).................. 101779 I
Methylene diphenyl diisocyanate (4,4'-) (MDI)...... 101688 III
Methylionones (a-)................................. 79696 V
Methylpentynol..................................... 77758 V
Methylstyrene (a-)................................. 98839 I
Naphthalene........................................ 91203 IV
Naphthalene sulfonic acid (a-)..................... 85472 IV
Naphthalene sulfonic acid (b-)..................... 120183 IV
Naphthol (a-)...................................... 90153 IV
Naphthol (b-)...................................... 135193 IV
Naphtholsulfonic acid (1-)......................... 567180 V
Naphthylamine sulfonic acid (1,4-)................. 84866 V
Naphthylamine sulfonic acid (2,1-)................. 81163 V
Naphthylamine (1-)................................. 134327 V
Naphthylamine (2-)................................. 91598 V
Nitroaniline (m-).................................. 99092 II
Nitroaniline (o-).................................. 88744 I
Nitroanisole (o-).................................. 91236 III
Nitroanisole (p-).................................. 100174 III
Nitrobenzene....................................... 98953 I
Nitronaphthalene (1-).............................. 86577 IV
Nitrophenol (p-)................................... 100027 III
Nitrophenol (o-)................................... 88755 III
Nitropropane (2-).................................. 79469 II
Nitrotoluene (all isomers)......................... 1321126 III
Nitrotoluene (o-).................................. 88722 III
Nitrotoluene (m-).................................. 99081 III
Nitrotoluene (p-).................................. 99990 III
Nitroxylene........................................ 25168041 V
Nonylbenzene (branched)............................ 1081772 V
Nonylphenol........................................ 25154523 V
Octene-1........................................... 111660 I
Octylphenol........................................ 27193288 III
Paraformaldehyde................................... 30525894 I
Paraldehyde........................................ 123637 II
Pentachlorophenol.................................. 87865 III
Pentaerythritol.................................... 115775 I
Peracetic acid..................................... 79210 II
Perchloromethyl mercaptan.......................... 594423 IV
Phenanthrene....................................... 85018 V
Phenetidine (p-)................................... 156434 III
Phenol............................................. 108952 III
Phenolphthalein.................................... 77098 III
Phenolsulfonic acids (all isomers)................. 1333397 III
Phenyl anthranilic acid (all isomers).............. 91407 III
Phenylenediamine (p-).............................. 106503 I
Phloroglucinol..................................... 108736 III
Phosgene........................................... 75445 IV
Phthalic acid...................................... 88993 III
Phthalic anhydride................................. 85449 III
Phthalimide........................................ 85416 III
Phthalonitrile..................................... 91156 III
Picoline (b-)...................................... 108996 II
Piperazine......................................... 110850 I
Polyethylene glycol................................ 25322683 V
Polypropylene glycol............................... 25322694 V
Propiolactone (beta-).............................. 57578 I
Propionaldehyde.................................... 123386 IV
Propionic acid..................................... 79094 I
Propylene carbonate................................ 108327 V
Propylene dichloride (1,2-dichloropropane)......... 78875 IV
Propylene glycol................................... 57556 I
Propylene glycol monomethyl ether.................. 107982 I
Propylene oxide.................................... 75569 I
Pyrene............................................. 129000 V
Pyridine........................................... 110861 II
p-tert-Butyl toluene............................... 98511 III
Quinone............................................ 106514 III
Resorcinol......................................... 108463 I
Salicylic acid..................................... 69727 III
Sodium methoxide................................... 124414 IV
Sodium phenate..................................... 139026 III
Stilbene........................................... 588590 III
Styrene............................................ 100425 I
Succinic acid...................................... 110156 I
Succinonitrile..................................... 110612 I
Sulfanilic acid.................................... 121573 III
Sulfolane.......................................... 126330 II
Tartaric acid...................................... 526830 I
Terephthalic acid.................................. 100210 II
Tetrabromophthalic anhydride....................... 632791 III
Tetrachlorobenzene (1,2,4,5-)...................... 95943 I
Tetrachloroethane (1,1,2,2-)....................... 79345 II
Tetrachloroethylene (Perchloroethylene)............ 127184 I
Tetrachlorophthalic- 117088 III
anhydride.
Tetraethyl lead.................................... 78002 IV
Tetraethylene glycol............................... 112607 I
Tetraethylene- 112572 V
pentamine.
Tetrahydrofuran.................................... 109999 I
Tetrahydronapthalene............................... 119642 IV
Tetrahydrophthalic anhydride....................... 85438 II
Tetramethylene- 110601 II
diamine.
Tetramethylethylenediamine......................... 110189 V
Tetramethyllead.................................... 75741 V
Thiocarbanilide.................................... 102089 V
Toluene............................................ 108883 I
Toluene 2,4 diamine................................ 95807 II
Toluene 2,4 diisocyanate........................... 584849 II
Toluene diisocyanates (mixture).................... 26471625 II
Toluene sulfonic acids............................. 104154 III
Toluenesulfonyl chloride........................... 98599 III
Toluidine (o-)..................................... 95534 II
Trichloroaniline- 634935 III
(2,4,6-).
Trichlorobenzene (1,2,3-).......................... 87616 V
Trichlorobenzene (1,2,4-).......................... 120821 I
Trichloroethane 71556 II
(1,1,1-)
Trichloroethane (1,1,2-) (Vinyl trichloride)....... 79005 II
Trichloroethylene.................................. 79016 I
Trichlorofluoromethane............................. 75694 I
Trichlorophenol 95954 I
(2,4,5-).
(1,1,2-) Trichloro 76131 I
(1,2,2-) trifluoroethane.
Triethanolamine.................................... 102716 I
Triethylamine...................................... 121448 IV
Triethylene glycol................................. 112276 I
Triethylene glycol 112492 I
dimethyl ether.
Triethylene glycol monoethyl ether................. 112505 V
Triethylene glycol monomethyl ether................ 112356 I
Trimethylamine..................................... 75503 IV
Trimethylcyclohexanol.............................. 933482 IV
Trimethylcyclo- 2408379 IV
hexanone.
Trimethylcyclo- 34216347 V
hexylamine.
Trimethylolpropane................................. 77996 I
Trimethylpentane (2,2,4-).......................... 540841 V
Tripropylene glycol................................ 24800440 V
Vinyl acetate...................................... 108054 II
Vinyl chloride (Chloroethylene).................... 75014 I
Vinyl toluene...................................... 25013154 III
Vinylcyclohexene (4-).............................. 100403 II
Vinylidene chloride 75354 II
(1,1-dichloroethylene).
Vinyl(N-)-pyrrolidone(2-).......................... 88120 V
Xanthates.......................................... 140896 V
Xylene sulfonic acid............................... 25321419 III
Xylenes (NOS)c..................................... 1330207 I
Xylene (m-)........................................ 108383 I
Xylene (o-)........................................ 95476 I
Xylene (p-)........................................ 106423 I
Xylenols (Mixed)................................... 1300716 V
Xylidene........................................... 1300738 III
------------------------------------------------------------------------
aIsomer means all structural arrangements for the same number of atoms
of each element and does not mean salts, esters, or derivatives.
bCAS Number = Chemical Abstract Service number.
cNOS = not otherwise specified.
dNo CAS number assigned.
Table 2. to Subpart F--Organic Hazardous Air Pollutants
------------------------------------------------------------------------
Chemical name a,b CAS No.c
------------------------------------------------------------------------
Acetaldehyde................................................ 75070
Acetamide................................................... 60355
Acetonitrile................................................ 75058
Acetophenone................................................ 98862
Acrolein.................................................... 107028
Acrylamide.................................................. 79061
Acrylic acid................................................ 79107
Acrylonitrile............................................... 107131
Allyl chloride.............................................. 107051
Aniline..................................................... 62533
Anisidine (o-).............................................. 90040
Benzene..................................................... 71432
Benzotrichloride............................................ 98077
Benzyl chloride............................................. 100447
Biphenyl.................................................... 92524
Bis(chloromethyl)ether...................................... 542881
Bromoform................................................... 75252
Butadiene (1,3-)............................................ 106990
Caprolactam................................................. 105602
Carbon disulfide............................................ 75150
Carbon tetrachloride........................................ 56235
Chloroacetic acid........................................... 79118
Chloroacetophenone (2-)..................................... 532274
Chlorobenzene............................................... 108907
2-Chloro-1,3-butadiene (Chloroprene)........................ 126998
Chloroform.................................................. 67663
Cresols and cresylic acids (mixed).......................... 1319773
Cresol and cresylic acid (o-)............................... 95487
Cresol and cresylic acid (m-)............................... 108394
Cresol and cresylic acid (p-)............................... 106445
Cumene...................................................... 98828
Dichlorobenzene (p-)........................................ 106467
Dichlorobenzidine (3,3'-)................................... 91941
Dichloroethane (1,2-) (Ethylene dichloride) (EDC)........... 107062
Dichloroethylether 111444
(Bis(2-chloroethyl)
ether).
Dichloropropene (1,3-)...................................... 542756
Diethanolamine (2,2'- 111422
Iminodiethanol).
Dimethylaniline (N,N-)...................................... 121697
Diethyl sulfate............................................. 64675
Dimethylbenzidine (3,3'-)................................... 119937
Dimethylformamide (N,N-).................................... 68122
Dimethylhydrazine (1,1-).................................... 57147
Dimethyl phthalate.......................................... 131113
Dimethyl sulfate............................................ 77781
Dinitrophenol (2,4-)........................................ 51285
Dinitrotoluene (2,4-)....................................... 121142
Dioxane (1,4-)(1,4- 123911
Diethyleneoxide).
1,2-Diphenylhydrazine....................................... 122667
Epichlorohydrin (1-Chloro-2,3-epoxypropane)................. 106898
Ethyl acrylate.............................................. 140885
Ethylbenzene................................................ 100414
Ethyl chloride (Chloroethane)............................... 75003
Ethylene dibromide 106934
(Dibromoethane).
Ethylene glycol............................................. 107211
Ethylene oxide.............................................. 75218
Ethylidene dichloride 75343
(1,1-Dichloroethane).
Formaldehyde................................................ 50000
Glycol ethersd
Hexachlorobenzene........................................... 118741
Hexachlorobutadiene......................................... 87683
Hexachloroethane............................................ 67721
Hexane...................................................... 100543
Hydroquinone................................................ 123319
Isophorone.................................................. 78591
Maleic anhydride............................................ 108316
Methanol.................................................... 67561
Methyl bromide (Bromomethane)............................... 74839
Methyl chloride (Chloromethane)............................. 74873
Methyl ethyl ketone 78933
(2-Butanone).
Methyl hydrazine............................................ 60344
Methyl isobutyl ketone (Hexone)............................. 108101
Methyl isocyanate........................................... 624839
Methyl methacrylate......................................... 80626
Methyl tert-butyl ether..................................... 1634044
Methylene chloride (Dichloromethane)........................ 75092
Methylene diphenyl diisocyanate (4,4'-) (MDI)............... 101688
Methylenedianiline (4,4'-).................................. 101779
Naphthalene................................................. 91203
Nitrobenzene................................................ 98953
Nitrophenol (p-)............................................ 100027
Nitropropane (2-)........................................... 79469
Phenol...................................................... 108952
Phenylenediamine (p-)....................................... 106503
Phosgene.................................................... 75445
Phthalic anhydride.......................................... 85449
Polycyclic organic mattere
Propiolactone (beta-)....................................... 57578
Propionaldehyde............................................. 123386
Propylene dichloride 78875
(1,2-Dichloropropane).
Propylene oxide............................................. 75569
Quinone..................................................... 106514
Styrene..................................................... 100425
Tetrachloroethane (1,1,2,2-)................................ 79345
Tetrachloroethylene (Perchloroethylene)..................... 127184
Toluene..................................................... 108883
Toluene diamine (2,4-)...................................... 95807
Toluene diisocyanate (2,4-)................................. 584849
Toluidine (o-).............................................. 95534
Trichlorobenzene (1,2,4-)................................... 120821
Trichloroethane (1,1,1-) (Methyl chloroform)................ 71556
Trichloroethane (1,1,2-) (Vinyl trichloride)................ 79005
Trichloroethylene........................................... 79016
Trichlorophenol (2,4,5-).................................... 95954
Triethylamine............................................... 121448
Trimethylpentane (2,2,4-)................................... 540841
Vinyl acetate............................................... 108054
Vinyl chloride (chloroethylene)............................. 75014
Vinylidene chloride 75354
(1,1-Dichloroethylene).
Xylenes (NOS)............................................... 1330207
Xylene (m-)................................................. 108383
Xylene (o-)................................................. 95476
Xylene (p-)................................................. 106423
------------------------------------------------------------------------
aFor all listings above containing the word ``Compounds'' and for glycol
ethers, the following applies: Unless otherwise specified, these
listings are defined as including any unique chemical substance that
contains the named chemical (i.e., antimony, arsenic) as part of that
chemical's infrastructure.
bIsomer means all structural arrangements for the same number of atoms
of each element and does not mean salts, esters, or derivatives.
cCAS Number=Chemical Abstract Service number.
dIncludes mono- and di- ethers of ethylene glycol, diethylene glycol,
and triethylene glycol R-(OCH2CH2)n-OR' where:
n=1, 2, or 3;
R=alkyl or aryl groups; and
R'=R, H, or groups which, when removed, yield glycol ethers with the
structure: R-(OCH2CH2)n-OH
Polymers are excluded from the glycol category.
eincludes organic compounds with more than one benzene ring, and which
have a boiling point greater than or equal to 100 deg.C.
Table 3 to Subpart F--General Provisions Applicability to subparts F, G, and Ha
----------------------------------------------------------------------------------------------------------------
Applies to
Reference Subparts F, G, Comment
and H
----------------------------------------------------------------------------------------------------------------
63.1(a)(1)........................................ Yes............. Overlap clarified in Sec. 63.101, Sec.
63.111, Sec. 63.161.
63.1(a)(2)........................................ Yes.
63.1(a)(3)........................................ Yes............. Sec. 63.110 and Sec. 63.160(b) of subparts
G and H identify which standards are
overridden.
63.1(a)(4)........................................ No.............. Subpart F specifies applicability of each
paragraph in subpart A to subparts F, G,
and H.
63.1(a)(5)-(a)(9)................................. No.
63.1(a)(10)....................................... No.............. Subparts F, G, and H specify calendar or
operating day.
63.1(a)(11)....................................... No.............. Subpart F Sec. 63.103(d) specifies
acceptable methods for submitting
reportsa.
63.1(a)(12)-(a)(14)............................... Yes.
63.1(b)(1)........................................ No.............. Subpart F specifies applicability.
63.1(b)(2)........................................ Yes.
63.1(b)(3)........................................ No.
63.1(c)(1)........................................ No.............. Subpart F specifies applicability.
63.1(c)(2)........................................ No.............. Area sources are not subject to subparts
F, G, and H.
63.1(c)(3)........................................ No.
63.1(c)(4)........................................ Yes.
63.1(c)(5)........................................ No.............. Subparts G and H specify applicable
notification requirements.
63.1(d)........................................... No.
63.1(e)........................................... No.............. Subparts F, G, and H established before
permit program.
63.2.............................................. Yes............. Subpart F Sec. 63.103 specifies those
subpart A definitions that apply to the
HON. Subpart F definition of ``source''
is equivalent to subpart A definition of
``affected source''.
63.3.............................................. No.............. Units of measure are spelled out in
subparts F, G, and H.
63.4(a)(1)-(a)(3)................................. Yes.
63.4(a)(4)........................................ No.
63.4(a)(5)........................................ Yes.
63.4(b)........................................... Yes.
63.4(c)........................................... Yes.
63.5(a)(1)........................................ Yes............. Except replace term ``source'' and
``stationary source'' in Sec. 63.5(a)(1)
of subpart A with ``affected source''.
63.5(a)(2)........................................ Yes.
63.5(b)(1)........................................ Yes.
63.5(b)(2)........................................ No.
63.5(b)(3)........................................ Yes.
63.5(b)(4)........................................ Yes............. Except the cross reference to Sec. 63.9(b)
is changed to Sec. 63.9(b) (4) and (5).
Subpart F overrides Sec. 63.9 (b)(2) and
(b)(3).
63.5(b)(5)........................................ Yes.
63.5(b)(6)........................................ Yes.
63.5(c)........................................... No.
63.5(d)(1)(i)..................................... No.............. Subpart G Sec. 63.151(b) (2)(ii) and
(2)(iii) specify the applicability and
timing of this submittal for sources
subject to subpart G.
63.5(d)(1)(ii).................................... Yes............. Except that for affected sources subject
to subpart G instead of the information
in Sec. 63.5(d)(1)(ii)(H), submit the
implementation plan information specified
in Sec. 63.151(e).
63.5(d)(1)(iii)................................... No. Subpart G requires submittal of the
notification of compliance status in Sec.
63.152(b).
63.5(d)(2)........................................ No.
63.5(d)(3)........................................ Yes............. Except Sec. 63.5(d)(3)(ii) does not apply
to subpart G.
63.5(d)(4)........................................ Yes.
63.5(e)........................................... Yes.
63.5(f)(1)........................................ Yes.
63.5(f)(2)........................................ Yes.
63.5(f)(3)........................................ Yes............. Except the cross-reference to Sec.
63.5(d)(1) is changed to Sec.
63.151(b)(ii) of subpart G, and the cross-
reference to (b)(2) does not apply.
63.5(f)(4)........................................ Yes.
63.6(a)........................................... Yes.
63.6(b)(1)........................................ No.............. Subparts F and H specify compliance dates
for sources subject to subparts F, G, and
H.
63.6(b)(2)........................................ No.
63.6(b)(3)........................................ Yes.
63.6(b)(4)........................................ No.............. May apply when standards are proposed
under section 112(f) of the Act.
63.6(b)(5)........................................ No.............. Subparts G and H include notification
requirements.
63.6(b)(6)........................................ No.
63.6(b)(7)........................................ No.
63.6(c)(1)........................................ No.............. Subpart F specifies the compliance date.
63.6(c)(2)........................................ No.
63.6(c)(3)........................................ No.
63.6(c)(4)........................................ No.
63.6(c)(5)........................................ Yes.
63.6(d)........................................... No.
63.6(e)........................................... Yes............. Does not apply to Group 2 emission points
unless they are included in an emissions
averageb.
63.6(f)(1)........................................ No.............. Sec. 63.102(a) of subpart F specifies when
the standards apply.
63.6(f)(2)(i)..................................... Yes.
63.6(f)(2)(ii).................................... Yes............. Sec. 63.151(c)(2) of subpart G specifies
the use of monitoring data in determining
compliance with subpart G.
63.6(f)(2)(iii) (A), (B), and (C)................. Yes.
63.6(f)(2)(iii)(D)................................ No.
63.6(f)(2)(iv).................................... Yes.
63.6(f)(2)(v)..................................... Yes.
63.6(f)(3)........................................ Yes.
63.6(g)........................................... No.............. Procedures specified in Sec. 63.102(b) of
subpart F.
63.6(h)........................................... No.
63.6(i)(1)........................................ Yes.
63.6(i)(2)........................................ Yes.
63.6(i)(3)........................................ No.............. Sec. 63.151(a)(6) of subpart G specifies
procedures.
63.6(i)(4)(i)(A).................................. Yes.
63.6(i)(4)(i)(B).................................. No.............. Dates are specified in Sec. 63.151(a)(6)
of subpart G.
63.6(i)(4)(ii).................................... No.
63.6(i)(5)-(14)................................... Yes.
63.6(i)(15)....................................... No.
63.6(i)(16)....................................... Yes.
63.6(j)........................................... Yes.
63.7(a)(1)........................................ No.............. Subparts F, G, and H specify required
testing and compliance demonstration
procedures.
63.7(a)(2)........................................ No.............. Test results must be submitted in the
notification of compliance status due 150
days after compliance date, as specified
in Sec. 63.152(b) of subparts G and H.
63.7(a)(3)........................................ Yes.
63.7(b)........................................... No.
63.7(c)........................................... No.
63.7(d)........................................... Yes.
63.7(e)(1)........................................ Yes.
63.7(e)(2)........................................ Yes.
63.7(e)(3)........................................ No.............. Subparts F, G, and H specify test methods
and procedures.
63.7(e)(4)........................................ Yes.
63.7(f)........................................... No.............. Subparts F, G, and H specify applicable
methods and provide alternatives.
63.7(g)........................................... No.............. Performance test reporting specified in
Sec. 63.152(b) of subparts G and H.
63.7(h)(1)........................................ Yes.
63.7(h)(2)........................................ Yes.
63.7(h)(3)........................................ No.............. Sec. 63.103(b)(5) of subpart F specifies
provisions for requests to waive
performance tests.
63.7(h)(4)........................................ No.
63.7(h)(5)........................................ Yes.
63.8(a)(1)........................................ Yes.
63.8(a)(2)........................................ No.
63.8(a)(3)........................................ No.
63.8(a)(4)........................................ Yes.
63.8(b)(1)........................................ Yes.
63.8(b)(2)........................................ No.............. Subparts G and H specify locations to
conduct monitoring.
63.8(b)(3)........................................ Yes.
63.8(c)(1)(i)..................................... Yes.
63.8(c)(1)(ii).................................... No.............. Addressed by periodic reports in Sec.
63.152(c) of subpart G.
63.8(c)(1)(iii)................................... Yes.
63.8(c)(2)........................................ Yes.
63.8(c)(3)........................................ Yes.
63.8(c)(4)........................................ No.............. HON specifies monitoring frequency in Sec.
63.111 and Sec. 63.152(f) of subpart G.
63.8(c)(5)-(c)(8)................................. No.
63.8(d)........................................... No.
63.8(e)........................................... No.
63.8(f)(1)-(f)(3)................................. Yes.
63.8(f)(4)(i)..................................... No.............. Timeframe for submitting request specified
in Sec. 63.152(g)(1) of subpart G.
63.8(f)(4)(ii).................................... Yes.
63.8(f)(4)(iii)................................... No.
63.8(f)(5)(i)..................................... Yes.
63.8(f)(5)(ii).................................... No.
63.8(f)(5)(iii)................................... Yes.
63.8(f)(6)........................................ No.............. Subparts G and H do not require CEM's.
63.8(g)........................................... No.............. Data reduction procedures specified in
Sec. 63.152(f) of subpart G.
63.9(a)........................................... Yes.
63.9(b)(1)(i)..................................... No.............. Specified in Sec. 63.151(b)(2)(ii) of
subpart G.
63.9(b)(1)(ii).................................... No.
63.9(b)(2)........................................ No.............. Initial notification provisions are
specified in Sec. 63.151(b) of subpart G.
63.9(b)(3)........................................ No.
63.9(b)(4)........................................ Yes............. Except that the notification in Sec.
63.9(b)(4)(i) shall be submitted at the
time specified in Sec. 63.151(b)(2)(ii)
of subpart G.
63.9(b)(5)........................................ Yes............. Except that the notification in Sec.
63.9(b)(5) shall be submitted at the time
specified in Sec. 63.151(b)(2)(ii) of
subpart G.
63.9(c)........................................... Yes.
63.9(d)........................................... Yes.
63.9(e)........................................... No.
63.9(f)........................................... No.
63.9(g)........................................... No.
63.9(h)........................................... No.............. Sec. 63.152(b) of subpart G specifies
notification of compliance status
requirements.
63.9(i)........................................... Yes.
63.9(j)........................................... No.
63.10(a).......................................... Yes.
63.10(b)(1)....................................... No.............. Sec. 63.103(c) of subpart F specifies
record retention requirements.
63.10(b)(2)....................................... No.............. Sec. 63.103(c) of subpart F specifies
required records.
63.10(b)(3)....................................... No.
63.10(c).......................................... No.
63.10(d)(1)....................................... No.
63.10(d)(2)....................................... No.............. Sec. 63.152(b) of subpart F specifies
performance test reporting.
63.10(d)(3)....................................... No.
63.10(d)(4)....................................... Yes.............
63.10(d)(5)(i).................................... Yes............. Except that reports required by Sec.
63.10(d)(5)(i) shall be submitted at the
time specified in Sec. 63.152(c) of
subpart G..
63.10(d)(5)(ii)................................... Yes.
63.10(e).......................................... No.
63.10(f).......................................... Yes.
63.11-63.15....................................... Yes.
----------------------------------------------------------------------------------------------------------------
aWherever subpart A specifies ``postmark'' dates, submittals may be sent by methods other than the U.S. Mail
(e.g., by fax or courier). Submittals shall be sent by the specified dates, but a postmark is not necessarily
required.
bThe plan, and any records or reports of start-up, shutdown, and malfunction do not apply to Group 2 emission
points unless they are included in an emissions average.
Subpart G--National Emission Standards for Organic Hazardous Air
Pollutants From the Synthetic Organic Chemical Manufacturing
Industry for Process Vents, Storage Vessels, Transfer Operations,
and Wastewater
Sec. 63.110 Applicability.
(a) This subpart applies to all process vents, storage vessels,
transfer racks, and wastewater streams within a source subject to
subpart F of this part.
(b) Overlap with other regulations for storage vessels.
(1) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, a Group 1 or Group 2 storage vessel that is also
subject to the provisions of 40 CFR part 60 subpart Kb is required to
comply only with the provisions of this subpart.
(2) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, a Group 1 storage vessel that is also subject to the
provisions of 40 CFR part 61 subpart Y is required to comply only with
the provisions of this subpart.
(3) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, a Group 2 storage vessel that is also subject to the
provisions of 40 CFR part 61 subpart Y is required to comply only with
the provisions of 40 CFR part 61 subpart Y. The recordkeeping and
reporting requirements of 40 CFR part 61 subpart Y will be accepted as
compliance with the recordkeeping and reporting requirements of this
subpart.
(c) Overlap with other regulations for transfer racks.
(1) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, a Group 1 transfer rack that is also subject to the
provisions of 40 CFR part 61 subpart BB is required to comply only with
the provisions of this subpart.
(2) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, a Group 2 transfer rack that is also subject to the
provisions of 40 CFR part 61 subpart BB is required to comply with the
provisions of either paragraph (c)(2)(i) or (c)(2)(ii) of this subpart.
(i) If the transfer rack is subject to the control requirements
specified in Sec. 61.302 of 40 CFR part 61 subpart BB, then the
transfer rack is required to comply with the control requirements of
Sec. 61.302 of 40 CFR part 61 subpart BB. The owner or operator may
elect to comply with either the associated testing, monitoring,
reporting, and recordkeeping requirements of 40 CFR part 61 subpart BB
or with the testing, monitoring, recordkeeping, and reporting
requirements specified in this subpart for Group 1 transfer racks. The
owner or operator shall indicate this decision in either the
Notification of Compliance Status specified in Sec. 63.152(b) of this
subpart or in an operating permit application or amendment.
(ii) If the transfer rack is subject only to reporting and
recordkeeping requirements under 40 CFR part 61 subpart BB, then the
transfer rack is required to comply only with the reporting and
recordkeeping requirements specified in this subpart for Group 2
transfer racks and is exempt from the reporting and recordkeeping
requirements in 40 CFR part 61 subpart BB.
(d) Overlap with other regulations for process vents.
(1) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, a Group 1 process vent that is also subject to the
provisions of 40 CFR part 60 subpart III is required to comply only
with the provisions of this subpart.
(2) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, the owner or operator of a Group 2 process vent that is
also subject to the provisions of 40 CFR part 60 subpart III shall
determine requirements according to paragraphs (d)(2)(i) and (d)(2)(ii)
of this section.
(i) If the Group 2 process vent has a TRE value less than 1 as
determined by the procedures in 40 CFR part 60 subpart III, the process
vent is required to comply with the provisions in paragraphs
(d)(2)(i)(A) through (d)(2)(i)(C) of this section.
(A) The provisions in both this subpart and in 40 CFR part 60
subpart III for applicability determination and the associated
recordkeeping and reporting;
(B) The provisions in both this subpart and in 40 CFR part 60
subpart III for process changes and recalculation of the TRE index
value and the associated recordkeeping and reporting; and
(C) The control requirements in Sec. 60.612 of 40 CFR part 60
subpart III. The owner or operator may elect to comply with either the
associated testing, monitoring, reporting, and recordkeeping
requirements of 40 CFR part 60 subpart III or with the testing,
monitoring, reporting, and recordkeeping requirements specified in this
subpart for Group 1 process vents. The owner or operator shall indicate
this decision in either the Notification of Compliance Status specified
in Sec. 63.152(b) of this subpart or in an operating permit application
or amendment.
(ii) If the Group 2 process vent has a TRE value greater than or
equal to 1 as determined by the procedures in 40 CFR part 60 subpart
III, the process vent is required to comply only with the provisions
specified in paragraphs (d)(2)(ii)(A) through (d)(2)(ii)(D) of this
section.
(A) The provisions in both this subpart and in 40 CFR part 60
subpart III for applicability determination and the associated
recordkeeping and reporting;
(B) The provisions in both this subpart and in 40 CFR part 60
subpart III for process changes and recalculation of the TRE index
value and the associated recordkeeping and reporting;
(C) If the provisions of both this subpart and 40 CFR part 60
subpart III require continuous monitoring of recovery device operating
parameters, the process vent is required to comply only with the
provisions that are specified in this subpart for continuous monitoring
of recovery device operating parameters and the associated testing,
reporting, and recordkeeping.
(D) If only the provisions of 40 CFR part 60 subpart III require
continuous monitoring of recovery device operating parameters, the
process vent is required to comply only with the provisions that are
specified in 40 CFR part 60 subpart III for continuous monitoring of
recovery device operating parameters and the associated testing,
reporting, and recordkeeping.
(3) After the compliance dates specified in 63.100 of subpart F of
this part, if an owner or operator of a process vent subject to this
subpart that is also subject to the provisions of 40 CFR part 60
subpart III elects to control the process vent to the levels required
in Sec. 63.113 (a)(1) or (a)(2) of this subpart without calculating the
TRE index value for the vent according to the procedures specified in
Sec. 63.115(d) of this subpart then the owner or operator shall comply
with the testing, monitoring, reporting, and recordkeeping provisions
of this subpart and shall be exempt from the testing, monitoring,
reporting, and recordkeeping provisions of 40 CFR part 60 subpart III.
(4) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, a Group 1 process vent that is also subject to the
provisions of 40 CFR part 60 subpart NNN is required to comply only
with the provisions of this subpart.
(5) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, the owner or operator of a Group 2 process vent that is
also subject to the provisions of 40 CFR part 60 subpart NNN shall
determine requirements according to paragraphs (d)(5)(i) and (d)(5)(ii)
of this section.
(i) If the Group 2 process vent has a TRE value less than 1 as
determined by the procedures in 40 CFR part 60 subpart NNN, the process
vent is required to comply with the provisions in paragraphs
(d)(5)(i)(A) through (d)(5)(i)(C) of this section.
(A) The provisions in both this subpart and in 40 CFR part 60
subpart NNN for applicability determination and the associated
recordkeeping and reporting;
(B) The provisions in both this subpart and in 40 CFR part 60
subpart NNN for process changes and recalculation of the TRE index
value and the associated recordkeeping and reporting; and
(C) The control requirements in Sec. 60.662 of 40 CFR part 60
subpart NNN. The owner or operator may elect to comply with either the
associated testing, monitoring, reporting, and recordkeeping
requirements of 40 CFR part 60 subpart NNN or with the testing,
monitoring, reporting, and recordkeeping requirements specified in this
subpart for Group 1 process vents. The owner or operator shall indicate
this decision in either the Notification of Compliance Status specified
in Sec. 63.152(b) of this subpart or in an operating permit application
or amendment.
(ii) If the Group 2 process vent has a TRE value greater than or
equal to 1 as determined by the procedures in 40 CFR part 60 subpart
NNN, the process vent is required to comply only with the provisions
specified in paragraphs (d)(5)(ii)(A) through (d)(5)(ii)(D) of this
section.
(A) The provisions in both this subpart and in 40 CFR part 60
subpart NNN for applicability determination and the associated
recordkeeping and reporting;
(B) The provisions in both this subpart and in 40 CFR part 60
subpart NNN for process changes and recalculation of the TRE index
value and the associated recordkeeping and reporting;
(C) If the provisions of both this subpart and 40 CFR part 60
subpart NNN require continuous monitoring of recovery device operating
parameters, the process vent is required to comply only with the
provisions that are specified in this subpart for continuous monitoring
of recovery device operating parameters and the associated testing,
reporting, and recordkeeping.
(D) If only the provisions of 40 CFR part 60 subpart NNN require
continuous monitoring of recovery device operating parameters, the
process vent is required to comply only with the provisions that are
specified in 40 CFR part 60 subpart NNN for continuous monitoring of
recovery device operating parameters and the associated testing,
reporting, and recordkeeping.
(6) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, if an owner or operator of a process vent subject to
this subpart that is also subject to the provisions of 40 CFR part 60
subpart NNN elects to control the process vent to the levels required
in Sec. 63.113(a)(1) or (a)(2) of this subpart without calculating the
TRE index value for the vent according to the procedures specified in
Sec. 63.115(d) of this subpart then the owner or operator shall comply
with the testing, monitoring, reporting, and recordkeeping provisions
of this subpart and shall be exempt from the testing, monitoring,
reporting, and recordkeeping provisions of 40 CFR part 60 subpart NNN.
(7) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, a Group 1 process vent that is also subject to the
provisions of 40 CFR part 60 subpart RRR is required to comply only
with the provisions of this subpart.
(8) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, the owner or operator of a Group 2 process vent that is
also subject to the provisions of 40 CFR part 60 subpart RRR shall
determine requirements according to paragraphs (d)(8)(i) and (d)(8)(ii)
of this section.
(i) If the Group 2 process vent has a TRE value less than 1 as
determined by the procedures in 40 CFR part 60 subpart RRR, the process
vent is required to comply with the provisions in paragraphs
(d)(8)(i)(A) through (d)(8)(i)(C) of this section.
(A) The provisions in both this subpart and in 40 CFR part 60
subpart RRR for applicability determination and the associated
recordkeeping and reporting;
(B) The provisions in both this subpart and in 40 CFR part 60
subpart RRR for process changes and recalculation of the TRE index
value and the associated recordkeeping and reporting; and
(C) The control requirements in Sec. 60.702 of 40 CFR part 60
subpart RRR. The owner or operator may elect to comply with either the
associated testing, monitoring, reporting, and recordkeeping
requirements of 40 CFR part 60 subpart RRR or with the testing,
monitoring, reporting, and recordkeeping requirements specified in this
subpart for Group 1 process vents. The owner or operator shall indicate
this decision in either the Notification of Compliance Status specified
in Sec. 63.152(b) of this subpart or in an operating permit application
or amendment.
(ii) If the Group 2 process vent has a TRE value greater than or
equal to 1 as determined by the procedures in 40 CFR part 60 subpart
RRR, the process vent is required to comply only with the provisions
specified in paragraphs (d)(8)(ii)(A) through (d)(8)(ii)(D) of this
section.
(A) The provisions in both this subpart and in 40 CFR part 60
subpart RRR for applicability determination and the associated
recordkeeping and reporting;
(B) The provisions in both this subpart and in 40 CFR part 60
subpart RRR for process changes and recalculation of the TRE index
value and the associated recordkeeping and reporting;
(C) If the provisions of both this subpart and 40 CFR part 60
subpart RRR require continuous monitoring of recovery device operating
parameters, the process vent is required to comply only with the
provisions that are specified in this subpart for continuous monitoring
of recovery device operating parameters and the associated testing,
reporting, and recordkeeping.
(D) If only the provisions of 40 CFR part 60 subpart RRR require
continuous monitoring of recovery device operating parameters, the
process vent is required to comply only with the provisions that are
specified in 40 CFR part 60 subpart RRR for continuous monitoring of
recovery device operating parameters and the associated testing,
reporting, and recordkeeping.
(9) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, if an owner or operator of a process vent subject to
this subpart that is also subject to the provisions of 40 CFR part 60
subpart RRR elects to control the process vent to the levels required
in Sec. 63.113(a)(1) or (a)(2) of this subpart without calculating the
TRE index value for the vent according to the procedures specified in
Sec. 63.115(d) of this subpart then the owner or operator shall comply
with the testing, monitoring, reporting, and recordkeeping provisions
of this subpart and shall be exempt from the testing, monitoring,
reporting, and recordkeeping provisions of 40 CFR part 60 subpart RRR.
(e) Overlap with other regulations for wastewater.
(1) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, a Group 1 or Group 2 wastewater stream that is also
subject to the provisions of 40 CFR part 61 subpart FF is required to
comply with the provisions of both this subpart and 40 CFR part 61
subpart FF.
(2) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, the owner or operator of any Group 1 or Group 2
wastewater stream that is also subject to provisions in 40 CFR parts
260 through 272 shall comply with the requirements of either paragraph
(e)(2)(i) or (e)(2)(ii) of this section.
(i) For each Group 1 or Group 2 wastewater stream, the owner or
operator shall comply with the more stringent control requirements
(e.g., waste management units, numerical treatment standards, etc.) and
the more stringent testing, monitoring, recordkeeping, and reporting
requirements that overlap between the provisions of this subpart and
the provisions of 40 CFR parts 260 through 272. The owner or operator
shall keep a record of the information used to determine which
requirements were the most stringent and shall submit this information
if requested by the Administrator; or
(ii) The owner or operator shall submit as part of the
Implementation Plan required by Sec. 63.151(c) of this subpart or as
part of an operating permit application a request for a case-by-case
determination of requirements. The request shall include the
information specified in paragraphs (e)(2)(ii)(A) and (e)(2)(ii)(B) of
this section.
(A) Identification of the wastewater streams that are subject to
this subpart and to provisions in 40 CFR parts 260 through 272,
determination of the Group 1/Group 2 status of those streams,
determination of whether or not those streams are listed or exhibit a
characteristic as specified in 40 CFR part 261, and determination of
whether the waste management unit is subject to permitting under 40 CFR
part 270.
(B) Identification of the specific control requirements (e.g.,
waste management units, numerical treatment standards, etc.) and
testing, monitoring, recordkeeping, and reporting requirements that
overlap between the provisions of this subpart and the provisions of 40
CFR parts 260 through 272.
(f) Overlap with the Vinyl Chloride NESHAP.
(1) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, the owner or operator of any Group 1 process vent that
is also subject to the provisions of 40 CFR part 61 subpart F shall
comply only with the provisions of this subpart.
(2) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, the owner or operator of any Group 2 process vent that
is also subject to the provisions of 40 CFR part 61 subpart F shall
comply with the provisions specified in either paragraph (f)(2)(i) or
(f)(2)(ii) of this subpart.
(i) If the process vent is already controlled by a combustion
device meeting the requirements of 40 CFR part 61 subpart F, then the
owner or operator shall comply with either the associated testing,
monitoring, reporting, and recordkeeping provisions for Group 1 process
vents in this subpart or the testing, monitoring, reporting, and
recordkeeping provisions of 40 CFR part 61 subpart F. The owner or
operator shall indicate this decision in either the Notification of
Compliance Status specified in Sec. 63.152(b) of this subpart or in an
operating permit application or amendment.
(ii) If the process vent is not already controlled by a combustion
device, then the owner or operator shall comply with the provisions of
both this subpart and 40 CFR part 61 subpart F.
(3) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, if an owner or operator of a process vent subject to
this subpart that is also subject to the provisions of 40 CFR part 61
subpart F elects to control the process vent to the levels required in
Sec. 63.113(a)(1) or (a)(2) of this subpart without calculating the TRE
index value for the vent according to the procedures specified in
Sec. 63.115(d) of this subpart then the owner or operator shall comply
with the testing, monitoring, reporting, and recordkeeping provisions
of this subpart and shall be exempt from the testing, monitoring,
reporting, and recordkeeping provisions of 40 CFR part 61 subpart F.
(4) After the compliance dates specified in Sec. 63.100 of subpart
F of this part, the owner or operator of a Group 1 or Group 2
wastewater stream that is also subject to the provisions of 40 CFR part
61 subpart F shall comply with the provisions of either paragraph
(f)(4)(i) or (f)(4)(ii) of this section.
(i) The owner or operator shall comply with the provisions of both
this subpart and 40 CFR part 61 subpart F or
(ii) The owner or operator may submit, as part of the
Implementation Plan required by Sec. 63.151(c) of this subpart or as
part of an operating permit application, information demonstrating how
compliance with 40 CFR part 61 subpart F will also ensure compliance
with this subpart. The information shall include a description of the
testing, monitoring, reporting, and recordkeeping that will be
performed.
Sec. 63.111 Definitions.
All terms used in this subpart shall have the meaning given them in
the Act, in subpart F of this part, and in this section, as follows.
Air oxidation reactor means a device or vessel in which air, or a
combination of air and oxygen, is used as an oxygen source in
combination with one or more organic reactants to produce one or more
organic compounds. Air oxidation reactor includes the product separator
and any associated vacuum pump or steam jet.
Automated monitoring and recording system means any means of
measuring values of monitored parameters and creating a hard copy or
computer record of the measured values that does not require manual
reading of monitoring instruments and manual transcription of data
values. Automated monitoring and recording systems include, but are not
limited to, computerized systems and strip charts.
Average concentration, as used in the wastewater provisions, means
the flow-weighted annual average concentration, as determined according
to the procedures specified in Sec. 63.144(b) of this subpart.
Average flow rate, as used in the wastewater provisions, means the
annual average flow rate, as determined according to the procedures
specified in Sec. 63.144(e) of this subpart.
Batch operation means a noncontinuous operation in which a discrete
quantity or batch of feed is charged into a chemical manufacturing
process unit and distilled or reacted at one time. Batch operation
includes noncontinuous operations in which the equipment is fed
intermittently or discontinuously. Addition of raw material and
withdrawal of product do not occur simultaneously in a batch operation.
After each batch operation, the equipment is generally emptied before a
fresh batch is started.
Boiler means any enclosed combustion device that extracts useful
energy in the form of steam and is not an incinerator.
By compound means by individual stream components, not carbon
equivalents.
Car-seal means a seal that is placed on a device that is used to
change the position of a valve (e.g., from opened to closed) in such a
way that the position of the valve cannot be changed without breaking
the seal.
Closed-vent system means a system that is not open to the
atmosphere and is composed of piping, ductwork, connections, and, if
necessary, flow inducing devices that transport gas or vapor from an
emission point to a control device or back into the process.
Combustion device means an individual unit of equipment, such as a
flare, incinerator, process heater, or boiler, used for the combustion
of organic hazardous air pollutant vapors.
Container, as used in the wastewater provisions, means any portable
waste management unit that has a capacity greater than or equal to 0.1
m3 in which a material is stored, transported, treated, or
otherwise handled. Examples of containers are drums, barrels, tank
trucks, barges, dumpsters, tank cars, dump trucks, and ships.
Continuous record means documentation, either in hard copy or
computer readable form, of data values measured at least once every 15
minutes and recorded at the frequency specified in Sec. 63.152(f) of
this subpart.
Continuous recorder means a data recording device that either
records an instantaneous data value at least once every 15 minutes or
records 15-minute or more frequent block average values.
Continuous seal means a seal that forms a continuous closure that
completely covers the space between the wall of the storage vessel and
the edge of the floating roof. A continuous seal may be a vapor-
mounted, liquid-mounted, or metallic shoe seal.
Continuous vapor processing system means a vapor processing system
that treats total organic compound vapors collected from tank trucks or
railcars on a demand basis without intermediate accumulation in a vapor
holder.
Control device means any equipment used for recovering or oxidizing
organic hazardous air pollutant vapors. Such equipment includes, but is
not limited to, absorbers, carbon adsorbers, condensers, incinerators,
flares, boilers, and process heaters. For process vents, recovery
devices are not considered control devices and for a steam stripper, a
primary condenser is not considered a control device.
Cover, as used in the wastewater provisions, means a device or
system which is placed on or over a waste management unit containing
wastewater or residuals so that the entire surface area is enclosed and
sealed to minimize air emissions. A cover may have openings necessary
for operation, inspection, and maintenance of the waste management unit
such as access hatches, sampling ports, and gauge wells provided that
each opening is closed and sealed when not in use. Examples of covers
include a fixed roof installed on a wastewater tank, a lid installed on
a container, and an air-supported enclosure installed over a waste
management unit.
Distillate receiver means overhead receivers, overhead
accumulators, reflux drums, and condenser(s) including ejector-
condenser(s) associated with a distillation unit.
Distillation unit means a device or vessel in which one or more
feed streams are separated into two or more exit streams, each exit
stream having component concentrations different from those in the feed
stream(s). The separation is achieved by the redistribution of the
components between the liquid and the vapor phases by vaporization and
condensation as they approach equilibrium within the distillation unit.
Distillation unit includes the distillate receiver, reboiler, and any
associated vacuum pump or steam jet.
Duct work means a conveyance system that does not meet the
definition of hard-piping.
External floating roof means a pontoon-type or double-deck-type
cover that rests on the liquid surface in a storage vessel or waste
management unit with no fixed roof.
Fill or filling means the introduction of organic hazardous air
pollutant into a storage vessel or the introduction of a wastewater
stream or residual into a waste management unit, but not necessarily to
complete capacity.
First attempt at repair means to take action for the purpose of
stopping or reducing leakage of organic material to the atmosphere.
Fixed roof means a cover that is mounted on a waste management unit
or storage vessel in a stationary manner and that does not move with
fluctuations in liquid level.
Flame zone means the portion of the combustion chamber in a boiler
occupied by the flame envelope.
Floating roof means a cover consisting of a double deck, pontoon
single deck, internal floating cover or covered floating roof, which
rests upon and is supported by the liquid being contained, and is
equipped with a closure seal or seals to close the space between the
roof edge and waste management unit or storage vessel wall.
Flow indicator means a device which indicates whether gas flow is
present in a line.
Group 1 process vent means a process vent for which the flow rate
is greater than or equal to 0.005 standard cubic meter per minute, the
total organic HAP concentration is greater than or equal to 50 parts
per million by volume, and the total resource effectiveness index
value, calculated according to Sec. 63.115 of this subpart, is less
than or equal to 1.0.
Group 2 process vent means a process vent for which the flow rate
is less than 0.005 standard cubic meter per minute, the total organic
HAP concentration is less than 50 parts per million by volume or the
total resource effectiveness index value, calculated according to
Sec. 63.115 of this subpart, is greater than 1.0.
Group 1 storage vessel means a storage vessel that meets the
criteria for design storage capacity and stored-liquid maximum true
vapor pressure specified in table 5 of this subpart for storage vessels
at existing sources, and in table 6 of this subpart for storage vessels
at new sources.
Group 2 storage vessel means a storage vessel that does not meet
the definition of a Group 1 storage vessel.
Group 1 transfer rack means a transfer rack that annually loads
greater than or equal to 0.65 million liter of liquid products that
contain organic hazardous air pollutants with a rack weighted average
vapor pressure greater than or equal to 10.3 kilopascals.
Group 2 transfer rack means a transfer rack that does not meet the
definition of Group 1 transfer rack.
Group 1 wastewater stream means a process wastewater stream from a
process unit at an existing or new source with a total volatile organic
hazardous air pollutant average concentration greater than or equal to
10,000 parts per million by weight of compounds listed in table 9 of
this subpart at any flowrate; or a process wastewater stream from a
process unit at an existing or new source that has an average flow rate
greater than or equal to 10 liters per minute and a total volatile
organic hazardous air pollutant average concentration greater than or
equal to 1,000 parts per million by weight. A process wastewater stream
from a process unit at a new source that has an average flow rate
greater than or equal to 0.02 liter per minute and an average
concentration of 10 parts per million by weight or greater of any one
of the compounds listed in table 8 of this subpart is also considered a
Group 1 wastewater stream. Average flow rate and total volatile organic
hazardous air pollutant average concentration are determined for the
point of generation of each process wastewater stream.
Group 2 wastewater stream means any process wastewater stream that
does not meet the definition of a Group 1 wastewater stream.
Halogenated vent stream or halogenated stream means a vent stream
from a process vent or transfer operation determined to have a mass
emission rate of halogen atoms contained in organic compounds of 0.45
kilograms per hour or greater determined by the procedures presented in
Sec. 63.115(d)(2)(v) of this subpart.
Halogens and hydrogen halides means hydrogen chloride (HCl),
chlorine (Cl2), hydrogen bromide (HBr), bromine (Br2), and
hydrogen fluoride (HF).
Hard-piping means tubing that is manufactured and properly
installed using good engineering judgement and standards, such as ANSI
B31-3.
Incinerator means an enclosed combustion device that is used for
destroying organic compounds. Auxiliary fuel may be used to heat waste
gas to combustion temperatures. Any energy recovery section present is
not physically formed into one manufactured or assembled unit with the
combustion section; rather, the energy recovery section is a separate
section following the combustion section and the two are joined by
ducts or connections carrying flue gas. The above energy recovery
section limitation does not apply to an energy recovery section used
solely to permit the incoming vent stream or combustion air.
Individual drain system means the system used to convey wastewater
streams from a process unit, product storage tank, feed storage tank,
or waste management unit to a waste management unit. The term includes
all process drains and junction boxes, together with their associated
sewer lines and other junction boxes, manholes, sumps, and lift
stations, down to the receiving waste management unit. A segregated
stormwater sewer system, which is a drain and collection system
designed and operated for the sole purpose of collecting rainfall-
runoff at a facility, and which is segregated from all other individual
drain systems, is excluded from this definition.
Intermittent vapor processing system means a vapor processing
system that employs an intermediate vapor holder to accumulate total
organic compound vapors collected from tank trucks or railcars, and
treats the accumulated vapors only during automatically controlled
cycles.
Internal floating roof means a cover that rests or floats on the
liquid surface (but not necessarily in complete contact with it) inside
a storage vessel or waste management unit that has a permanently
affixed roof.
Junction box means a manhole or access point to a wastewater sewer
system line or a lift station.
Liquid-mounted seal means a foam- or liquid-filled seal mounted in
contact with the liquid between the wall of the storage vessel or waste
management unit and the floating roof. The seal is mounted continuously
around the circumference of the vessel or unit.
Loading cycle means the time period from the beginning of filling a
tank truck or railcar until flow to the control device ceases, as
measured by the flow indicator.
Loading rack means a single system used to fill tank trucks and
railcars at a single geographic site. Loading equipment and operations
that are physically separate (i.e., do not share common piping, valves,
and other equipment) are considered to be separate loading racks.
Mass flow rate, as used in the wastewater provisions, means the
mass of a constituent in a wastewater stream, determined by multiplying
the average concentration of that constituent in the wastewater stream
by the annual volumetric flow rate and density of the wastewater
stream.
Maximum true vapor pressure means the equilibrium partial pressure
exerted by the total organic HAP's in the stored or transferred liquid
at the temperature equal to the highest calendar-month average of the
liquid storage or transfer temperature for liquids stored or
transferred above or below the ambient temperature or at the local
maximum monthly average temperature as reported by the National Weather
Service for liquids stored or transferred at the ambient temperature,
as determined:
(1) In accordance with methods described in American Petroleum
Institute Publication 2517, Evaporative Loss From External Floating-
Roof Tanks (incorporated by reference as specified in Sec. 63.14 of
subpart A of this part); or
(2) As obtained from standard reference texts; or
(3) As determined by the American Society for Testing and Materials
Method D2879-83 (incorporated by reference as specified in Sec. 63.14
of subpart A of this part); or
(4) Any other method approved by the Administrator.
Metallic shoe seal or mechanical shoe seal means a metal sheet that
is held vertically against the wall of the storage vessel by springs,
weighted levers, or other mechanisms and is connected to the floating
roof by braces or other means. A flexible coated fabric (envelope)
spans the annular space between the metal sheet and the floating roof.
Non-automated monitoring and recording system means manual reading
of values measured by monitoring instruments and manual transcription
of those values to create a record. Non-automated systems do not
include strip charts.
Oil-water separator or organic-water separator means a waste
management unit, generally a tank used to separate oil or organics from
water. An oil-water or organic-water separator consists of not only the
separation unit but also the forebay and other separator basins,
skimmers, weirs, grit chambers, sludge hoppers, and bar screens that
are located directly after the individual drain system and prior to
additional treatment units such as an air flotation unit, clarifier, or
biological treatment unit. Examples of an oil-water or organic-water
separator include, but are not limited to, an American Petroleum
Institute separator, parallel-plate interceptor, and corrugated-plate
interceptor with the associated ancillary equipment.
Operating permit means a permit required by 40 CFR part 70 or part
71.
Organic hazardous air pollutant or organic HAP means any of the
chemicals listed in table 2 of subpart F of this part.
Organic monitoring device means a unit of equipment used to
indicate the concentration level of organic compounds exiting a
recovery device based on a detection principle such as infra-red,
photoionization, or thermal conductivity.
Point of generation means the location where process wastewater
exits the process unit equipment.
[Note: The regulation allows determination of the
characteristics of a wastewater stream (1) at the point of
generation or (2) downstream of the point of generation if
corrections are made for changes in flow rate and VOHAP
concentration. Such changes include losses by air emissions;
reduction of VOHAP concentration or changes in flow rate by mixing
with other water or wastewater streams; and reduction in flow rate
or VOHAP concentration by treating or otherwise handling the
wastewater stream to remove or destroy HAP's.]
Primary fuel means the fuel that provides the principal heat input
to the device. To be considered primary, the fuel must be able to
sustain operation without the addition of other fuels.
Process heater means a device that transfers heat liberated by
burning fuel directly to process streams or to heat transfer liquids
other than water.
Process unit has the same meaning as chemical manufacturing process
unit as defined in Sec. 63.101 of subpart F of this part and means the
equipment assembled and connected by pipes or ducts to process raw
materials and to manufacture an intended product. For the purpose of
this subpart, process unit or chemical manufacturing process unit
includes air oxidation reactors and their associated product separators
and recovery devices; reactors and their associated product separators
and recovery devices; distillation units and their associated
distillate receivers and recovery devices; associated unit operations
(as defined in this section); and any feed, intermediate and product
storage vessels, product transfer racks, and connected ducts and
piping. A chemical manufacturing process unit includes pumps,
compressors, agitators, pressure relief devices, sampling connection
systems, open-ended valves or lines, valves, connectors,
instrumentation systems, and control devices or systems. A chemical
manufacturing process unit is identified by its primary product.
Process wastewater stream means a stream that contains process
wastewater as defined in Sec. 63.101 of subpart F of this part.
Product separator means phase separators, flash drums, knock-out
drums, decanters, degassers, and condenser(s) including ejector-
condenser(s) associated with a reactor or an air oxidation reactor.
Product tank, as used in the wastewater provisions, means a
stationary unit that is designed to contain an accumulation of
materials that are fed to or produced by a process unit, and is
constructed primarily of non-earthen materials (e.g., wood, concrete,
steel, plastic) which provide structural support. This term has the
same meaning as a product storage vessel.
Product tank drawdown means any material or mixture of materials
discharged from a product tank for the purpose of removing water or
other contaminants from the product tank.
Rack-weighted average partial pressure means the throughput
weighted average of the average maximum true vapor pressure of liquids
containing organic HAP's transferred at a transfer rack. The rack-
weighted average partial pressure shall be calculated using the
equation below:
TR22AP94.200
where:
P=Rack-weighted average partial pressure, kilopascals.
Pi=Individual HAP maximum true vapor pressure, kilopascals.
Gi=Yearly volume of individual organic HAP transferred at the
rack, liters.
Reactor means a device or vessel in which one or more chemicals or
reactants, other than air, are combined or decomposed in such a way
that their molecular structures are altered and one or more new organic
compounds are formed. Reactor includes the product separator and any
associated vacuum pump or steam jet.
Recovery device means an individual unit of equipment capable of
and used for the purpose of recovering chemicals for use, reuse, or
sale. Recovery devices include, but are not limited to, absorbers,
carbon adsorbers, and condensers.
Relief valve means a valve used only to release an unplanned,
nonroutine discharge. A relief valve discharge can result from an
operator error, a malfunction such as a power failure or equipment
failure, or other unexpected cause that requires immediate venting of
gas from process equipment in order to avoid safety hazards or
equipment damage.
Reference control technology for process vents means a combustion
device used to reduce organic HAP emissions by 98 percent, or to an
outlet concentration of 20 parts per million by volume.
Reference control technology for storage vessels means an internal
floating roof meeting the specifications of Sec. 63.119(b) of this
subpart, an external floating roof meeting the specifications of
Sec. 63.119(c) of this subpart, an external floating roof converted to
an internal floating roof meeting the specifications of Sec. 63.119(d)
of this subpart, or a closed-vent system to a control device achieving
95-percent reduction in organic HAP emissions. For purposes of
emissions averaging, these four technologies are considered equivalent.
Reference control technology for transfer racks means a combustion
device or recovery device used to reduce organic HAP emissions by 98
percent, or to an outlet concentration of 20 parts per million by
volume; or a vapor balancing system.
Reference control technology for wastewater means the use of: (1)
Controls specified in Sec. 63.133 through Sec. 63.137;
(2) A steam stripper meeting the specifications of Sec. 63.138(g)
of this subpart or any of the other alternative control measures
specified in Sec. 63.138 (b), (c), (d), and (e) of this subpart; and
(3) A control device to reduce by 95 percent (or to an outlet
concentration of 20 parts per million by volume for combustion devices)
the organic HAP emissions in the vapor streams vented from wastewater
tanks, oil-water separators, containers, surface impoundments,
individual drain systems, and treatment processes (including the design
steam stripper) managing wastewater.
Residual means any HAP-containing water or organic that is removed
from a wastewater stream by a waste management unit or treatment
process that does not destroy organics (nondestructive unit). Examples
of residuals from nondestructive wastewater management units are: The
organic layer and bottom residue removed by a decanter or organic-water
separator and the overheads from a steam stripper or air stripper.
Examples of materials which are not residuals are: Silt; mud; leaves;
bottoms from a steam stripper or air stripper; and sludges, ash, or
other materials removed from wastewater being treated by destructive
devices such as biological treatment units and incinerators.
Secondary fuel means a fuel fired through a burner other than the
primary fuel burner that provides supplementary heat in addition to the
heat provided by the primary fuel.
Sewer line means a lateral, trunk line, branch line, or other
conduit including, but not limited to, grates, trenches, etc., used to
convey wastewater streams or residuals to a downstream waste management
unit.
Simultaneous loading means, for a shared control device, loading of
organic HAP materials from more than one transfer arm at the same time
such that the beginning and ending times of loading cycles coincide or
overlap and there is no interruption in vapor flow to the shared
control device.
Single-seal system means a floating roof having one continuous seal
that completely covers the space between the wall of the storage vessel
and the edge of the floating roof. This seal may be a vapor-mounted,
liquid-mounted, or metallic shoe seal.
Specific gravity monitoring device means a unit of equipment used
to monitor specific gravity and having an accuracy of 0.02
specific gravity units.
Steam jet ejector means a steam nozzle which discharges a high-
velocity jet across a suction chamber that is connected to the
equipment to be evacuated.
Surface impoundment means a waste management unit which is a
natural topographic depression, manmade excavation, or diked area
formed primarily of earthen materials (although it may be lined with
manmade materials), which is designed to hold an accumulation of liquid
wastes or waste containing free liquids. A surface impoundment is used
for the purpose of treating, storing, or disposing of wastewater or
residuals, and is not an injection well. Examples of surface
impoundments are equalization, settling, and aeration pits, ponds, and
lagoons.
Temperature monitoring device means a unit of equipment used to
monitor temperature and having an accuracy of 1 percent of
the temperature being monitored expressed in degrees Celsius or
0.5 degrees Celsius ( deg.C), whichever is greater.
The 33/50 program means a voluntary pollution prevention initiative
established and administered by the EPA to encourage emissions
reductions of 17 chemicals emitted in large volumes by industrial
facilities. The EPA Document Number 741-K-92-001 provides more
information about the 33/50 program.
Total organic compounds or TOC, as used in the process vents
provisions, means those compounds measured according to the procedures
of Method 18 of 40 CFR part 60, appendix A.
Total volatile organic hazardous air pollutant concentration means
the sum of the concentrations of all individually-speciated organic
HAP's, as measured by Method 305 in appendix A of this part.
Total resource effectiveness index value or TRE index value means a
measure of the supplemental total resource requirement per unit
reduction of organic HAP associated with a process vent stream, based
on vent stream flow rate, emission rate of organic HAP, net heating
value, and corrosion properties (whether or not the vent stream
contains halogenated compounds), as quantified by the equations given
under Sec. 63.115 of this subpart.
Treatment process means a specific technique that removes or
destroys the organics in a wastewater or residual stream such as a
steam stripping unit, thin-film evaporation unit, waste incinerator,
biological treatment unit, or any other process applied to wastewater
streams or residuals to comply with Sec. 63.138 of this subpart. Most
treatment processes are conducted in tanks. Treatment processes are a
subset of waste management units.
Vapor collection system, as used in the transfer provisions, means
the equipment used to collect and transport organic HAP vapors
displaced during the loading of tank trucks or railcars. This does not
include the vapor collection system that is part of any tank truck or
railcar vapor collection manifold system.
Vapor-mounted seal means a continuous seal that completely covers
the annular space between the wall of the storage vessel or waste
management unit and the edge of the floating roof and is mounted such
that there is a vapor space between the stored liquid and the bottom of
the seal.
Vent stream, as used in the process vent provisions, means a
process vent as defined in Sec. 63.101 of subpart F of this part.
Volatile organic concentration or VO concentration refers to the
concentration of organic compounds (including both HAP and non-HAP
organic compounds) in a wastewater stream that is measured by Method
25D, as found in 40 CFR part 60, appendix A.
Volatile organic hazardous air pollutant concentration or VOHAP
concentration means the concentration of an individually-speciated
organic HAP in a wastewater stream or a residual that is measured by
Method 305 in appendix A of this part.
Waste management unit means any component, piece of equipment,
structure, or transport mechanism used in conveying, storing, treating,
or disposing of wastewater streams or residuals. Examples of waste
management units include wastewater tanks, air flotation units, surface
impoundments, containers, oil-water or organic-water separators,
individual drain systems, biological treatment units, waste
incinerators, and organic removal devices such as decanters, steam and
air stripper units, and thin-film evaporation units.
Wastewater stream means a stream that contains only wastewater as
defined in Sec. 63.101 of subpart F of this part.
Wastewater tank means a stationary waste management unit that is
designed to contain an accumulation of wastewater or residuals and is
constructed primarily of non-earthen materials (e.g., wood, concrete,
steel, plastic) which provide structural support. Wastewater tanks used
for flow equalization are included in this definition.
Water seal controls means a seal pot, p-leg trap, or other type of
trap filled with water (e.g, flooded sewers that maintain water levels
adequate to prevent air flow through the system) that creates a water
barrier between the sewer line and the atmosphere. The water level of
the seal must be maintained in the vertical leg of a drain in order to
be considered a water seal.
Sec. 63.112 Emission standard.
(a) The owner or operator of an existing source subject to the
requirements of this subpart shall control emissions of organic HAP's
to the level represented by the following equation:
EA = 0.02EPV1 + EPV2 +
0.05ES1 + ES2 + 0.02ETR1 +
ETR2 + EWW1C + EWW2
where:
EA = Emission rate, megagrams per year, allowed for the source.
0.02EPV1 = Sum of the residual emissions, megagrams per
year, from all Group 1 process vents, as defined in Sec. 63.111 of this
subpart.
EPV2 = Sum of the emissions, megagrams per year, from all
Group 2 process vents as defined in Sec. 63.111 of this subpart.
0.05ES1 = Sum of the residual emissions, megagrams per
year, from all Group 1 storage vessels, as defined in Sec. 63.111 of
this subpart.
ES2 = Sum of the emissions, megagrams per year, from all
Group 2 storage vessels, as defined in Sec. 63.111 of this subpart.
0.02ETR1 = Sum of the residual emissions, megagrams per
year, from all Group 1 transfer racks, as defined in Sec. 63.111 of
this subpart.
ETR2 = Sum of the emissions, megagrams per year, from all
Group 2 transfer racks, as defined in Sec. 63.111 of this subpart.
EWW1C = Sum of the residual emissions from all Group 1
wastewater streams, as defined in Sec. 63.111 of this subpart. This
term is calculated for each Group 1 stream according to the equation
for EWW1C in Sec. 63.150(g)(5)(i) of this subpart.
EWW2 = Sum of emissions from all Group 2 wastewater
streams, as defined in Sec. 63.111 of this subpart.
The emissions level represented by this equation is dependent on the
collection of emission points in the source. The level is not fixed and
can change as the emissions from each emission point change or as the
number of emission points in the source changes.
(b) The owner or operator of a new source subject to the
requirements of this subpart shall control emissions of organic HAP's
to the level represented by the equation in paragraph (a) of this
section.
(c) The owner or operator of an existing source shall demonstrate
compliance with the emission standard in paragraph (a) of this section
by following the procedures specified in paragraph (e) of this section
for all emission points, or by following the emissions averaging
compliance approach specified in paragraph (f) of this section for some
emission points and the procedures specified in paragraph (e) of this
section for all other emission points within the source.
(d) The owner or operator of a new source shall demonstrate
compliance with the emission standard in paragraph (b) of this section
only by following the procedures in paragraph (e) of this section. The
owner or operator of a new source may not use the emissions averaging
compliance approach.
(e) The owner or operator of an existing or new source may comply
with the process vent provisions in Secs. 63.113 through 63.118 of this
subpart, the storage vessel provisions in Secs. 63.119 through 63.123
of this subpart, the transfer operation provisions in Secs. 63.126
through 63.130 of this subpart, the wastewater provisions in
Secs. 63.131 through 63.147 of this subpart, and the leak inspection
provisions in Sec. 63.148 of this subpart.
(1) The owner or operator using this compliance approach shall also
comply with the requirements of Sec. 63.151 and Sec. 63.152 of this
subpart, as applicable.
(2) The owner or operator using this compliance approach is not
required to calculate the annual emission rate specified in paragraph
(a) of this section.
(f) The owner or operator of an existing source may elect to
control some of the emission points within the source to different
levels than specified under Secs. 63.113 through 63.148 of this subpart
by using an emissions averaging compliance approach as long as the
overall emissions for the source do not exceed the emission level
specified in paragraph (a) of this section. The owner or operator using
emissions averaging must meet the requirements in paragraphs (f)(1) and
(f)(2) of this section.
(1) Calculate emission debits and credits for those emission points
involved in the emissions average as specified in Sec. 63.150 of this
subpart; and
(2) Comply with the requirements of Sec. 63.151 and Sec. 63.152 of
this subpart, as applicable.
(g) A State may restrict the owner or operator of an existing
source to using only the procedures in paragraph (e) of this section to
comply with the emission standard in paragraph (a) of this section.
Sec. 63.113 Process vent provisions--reference control technology.
(a) The owner or operator of a Group 1 process vent as defined in
subpart F of this part and in this subpart shall comply with the
requirements of paragraph (a)(1), (a)(2), or (a)(3) of this section.
(1) Reduce emissions of organic HAP using a flare.
(i) The flare shall comply with the requirements of Sec. 63.11(b)
of subpart A of this part.
(ii) Halogenated vent streams, as defined in Sec. 63.111 of this
subpart, shall not be vented to a flare.
(2) Reduce emissions of total organic HAP by 98 weight-percent or
to a concentration of 20 parts per million by volume, on a dry basis,
corrected to 3 percent oxygen, whichever is less stringent. Compliance
can be determined by measuring either organic HAP or TOC using the
procedures in Sec. 63.116 of this subpart.
(3) Achieve and maintain a TRE index value greater than 1.0 at the
outlet of the final recovery device, or prior to release of the vent
stream to the atmosphere if no recovery device is present. In this
case, the vent shall comply with the provisions for a Group 2 process
vent specified in either paragraph (d) or (e) of this section,
whichever is applicable.
(b) If a boiler or process heater is used to comply with the
percent reduction requirement or concentration limit specified in
paragraph (a)(2) of this section, then the vent stream shall be
introduced into the flame zone of such a device.
(c) Halogenated Group 1 process vent streams that are combusted
shall be controlled according to paragraph (c)(1) or (c)(2) of this
section.
(1) If a combustion device is used to comply with paragraph (a)(2)
of this section for a halogenated vent stream, then the vent stream
shall be ducted from the combustion device to an additional control
device, including but not limited to a scrubber, before it is
discharged to the atmosphere.
(i) Except as provided in paragraph (c)(1)(ii) of this section, the
additional control device shall reduce overall emissions of hydrogen
halides and halogens, as defined in Sec. 63.111 of this subpart, by 99
percent or shall reduce the outlet mass of total hydrogen halides and
halogens to less than 0.45 kilogram per hour, whichever is less
stringent.
(ii) If a scrubber or other halogen control device was installed
prior to December 31, 1992, the control device shall reduce overall
emissions of hydrogen halides and halogens, as defined in Sec. 63.111
of this subpart, by 95 percent or shall reduce the outlet mass of total
hydrogen halides and halogens to less than 0.45 kilograms per hour,
whichever is less stringent.
(2) A control device, such as a scrubber, or other technique may be
used to reduce the vent stream halogen atom mass emission rate to less
than 0.45 kilogram per hour prior to any combustion control device, and
thus make the vent stream nonhalogenated; the vent stream must comply
with the requirements of paragraph (a)(1) or (a)(2) of this section.
(d) The owner or operator of a Group 2 process vent having a flow
rate greater than or equal to 0.005 standard cubic meter per minute, a
HAP concentration greater than or equal to 50 parts per million by
volume, and a TRE index value greater than 1.0 but less than or equal
to 4.0 shall maintain a TRE index value greater than 1.0 and shall
comply with the monitoring of recovery device parameters in
Sec. 63.114(b) or (c) of this subpart, the TRE index calculations of
Sec. 63.115 of this subpart, and the applicable reporting and
recordkeeping provisions of Secs. 63.117 and 63.118 of this subpart.
Such owner or operator is not subject to any other provisions of
Secs. 63.114 through 63.118 of this subpart.
(e) The owner or operator of a Group 2 process vent with a TRE
index greater than 4.0 shall maintain a TRE index value greater than
4.0, comply with the provisions for calculation of TRE index in
Sec. 63.115 of this subpart and the reporting and recordkeeping
provisions in Sec. 63.117(b) of this subpart, Sec. 63.118(c) of this
subpart, and Sec. 63.118(h) of this subpart, and is not subject to
monitoring or any other provisions of Secs. 63.114 through 63.118 of
this subpart.
(f) The owner or operator of a Group 2 process vent with a flow
rate less than 0.005 standard cubic meter per minute shall maintain a
flow rate less than 0.005 standard cubic meter per minute; comply with
the Group determination procedures in Sec. 63.115 (a), (b), and (e) of
this subpart; and the reporting and recordkeeping requirements in
Sec. 63.117(c) of this subpart, Sec. 63.118(d) of this subpart, and
Sec. 63.118(i) of this subpart; and is not subject to monitoring or any
other provisions of Secs. 63.114 through 63.118 of this subpart.
(g) The owner or operator of a Group 2 process vent with a
concentration less than 50 parts per million by volume shall maintain a
concentration less than 50 parts per million by volume; comply with the
Group determination procedures in Sec. 63.115 (a), (c), and (e) of this
subpart; the reporting and recordkeeping requirements in Sec. 63.117(d)
of this subpart, Sec. 63.118(e) of this subpart, and Sec. 63.118(j) of
this subpart; and is not subject to monitoring or any other provisions
of Secs. 63.114 through 63.118 of this subpart.
(h) The owner or operator of a process vent complying with
paragraph (a)(1) or (a)(2) of this section is not required to perform
the group determination described in Sec. 63.115 of this subpart.
Sec. 63.114 Process vent provisions--monitoring requirements.
(a) Each owner or operator of a process vent that uses a combustion
device to comply with the requirements in Sec. 63.113 (a)(1) or (a)(2)
of this subpart shall install monitoring equipment specified in
paragraph (a)(1), (a)(2), (a)(3), or (a)(4) of this section, depending
on the type of combustion device used. All monitoring equipment shall
be installed, calibrated, maintained, and operated according to
manufacturers specifications.
(1) Where an incinerator is used, a temperature monitoring device
equipped with a continuous recorder is required.
(i) Where an incinerator other than a catalytic incinerator is
used, a temperature monitoring device shall be installed in the firebox
or in the ductwork immediately downstream of the firebox in a position
before any substantial heat exchange occurs.
(ii) Where a catalytic incinerator is used, temperature monitoring
devices shall be installed in the gas stream immediately before and
after the catalyst bed.
(2) Where a flare is used, the following monitoring equipment is
required: A device (including but not limited to a thermocouple, ultra-
violet beam sensor, or infrared sensor) capable of continuously
detecting the presence of a pilot flame.
(3) Where a boiler or process heater of less than 44 megawatts
design heat input capacity is used, the following monitoring equipment
is required: A temperature monitoring device in the firebox equipped
with a continuous recorder. Any boiler or process heater in which all
vent streams are introduced with primary fuel or are used as the
primary fuel is exempt from this requirement.
(4) Where a scrubber is used with an incinerator, boiler, or
process heater in the case of halogenated vent streams, the following
monitoring equipment is required for the scrubber.
(i) A pH monitoring device equipped with a continuous recorder
shall be installed to monitor the pH of the scrubber effluent.
(ii) Flow meters equipped with continuous recorders shall be
located at the scrubber influent for liquid flow and the scrubber inlet
for gas stream flow.
(b) Each owner or operator of a process vent with a TRE index value
greater than 1.0 as specified under Sec. 63.113(a)(3) or Sec. 63.113(d)
of this subpart, that uses one or more product recovery devices shall
install either an organic monitoring device equipped with a continuous
recorder or the monitoring equipment specified in paragraph (b)(1),
(b)(2), or (b)(3) of this section, depending on the type of recovery
device used. All monitoring equipment shall be installed, calibrated,
and maintained according to the manufacturers specifications.
Monitoring is not required for process vents with TRE index values
greater than 4.0 as specified in Sec. 63.113(e) of this subpart.
(1) Where an absorber is the final recovery device in the recovery
system, a scrubbing liquid temperature monitoring device and a specific
gravity monitoring device, each equipped with a continuous recorder
shall be used;
(2) Where a condenser is the final recovery device in the recovery
system, a condenser exit (product side) temperature monitoring device
equipped with a continuous recorder shall be used;
(3) Where a carbon adsorber is the final recovery device in the
recovery system, an integrating regeneration stream flow monitoring
device having an accuracy of 10 percent, capable of
recording the total regeneration stream mass flow for each regeneration
cycle; and a carbon bed temperature monitoring device, capable of
recording the carbon bed temperature after each regeneration and within
15 minutes of completing any cooling cycle shall be used.
(c) An owner or operator of a process vent may request approval to
monitor parameters other than those listed in paragraph (a) or (b) of
this section. The request shall be submitted according to the
procedures specified in Sec. 63.151(f) or Sec. 63.152(e) of this
subpart. Approval shall be requested if the owner or operator:
(1) Uses a control device other than an incinerator, boiler,
process heater, or flare; or
(2) Maintains a TRE greater than 1.0 but less than or equal to 4.0
without a recovery device or with a recovery device other than the
recovery devices listed in paragraphs (a) and (b) of this section; or
(3) Uses one of the control or recovery devices listed in
paragraphs (a) and (b) of this section, but seeks to monitor a
parameter other than those specified in paragraphs (a) and (b) of this
section.
(d) The owner or operator of a process vent using a vent system
that contains bypass lines that could divert a vent stream away from
the control device used to comply with Sec. 63.113 (a)(1) or (a)(2) of
this subpart shall comply with paragraph (d)(1) or (d)(2) of this
section. Equipment such as low leg drains, high point bleeds, analyzer
vents, open-ended valves or lines, and pressure relief valves needed
for safety purposes are not subject to this paragraph.
(1) Install, calibrate, maintain, and operate a flow indicator that
determines whether vent stream flow is present at least once every 15
minutes. Records shall be generated as specified in Sec. 63.118(a)(3)
of this subpart. The flow indicator shall be installed at the entrance
to any bypass line that could divert the vent stream away from the
control device to the atmosphere; or
(2) Secure the bypass line valve in the closed position with a car-
seal or a lock-and-key type configuration. A visual inspection of the
seal or closure mechanism shall be performed at least once every month
to ensure that the valve is maintained in the closed position and the
vent stream is not diverted through the bypass line.
(e) The owner or operator shall establish a range that indicates
proper operation of the control or recovery device for each parameter
monitored under paragraphs (a), (b), and (c) of this section. In order
to establish the range, the information required in Sec. 63.152(b) of
this subpart shall be submitted in the Notification of Compliance
Status or the operating permit application or amendment.
Sec. 63.115 Process vent provisions--methods and procedures for
process vent group determination.
(a) For purposes of determining process vent stream flow rate,
total organic HAP or TOC concentration or TRE index value, as specified
under paragraph (b), (c), or (d) of this section, the sampling site
shall be after the last product recovery device (if any recovery
devices are present) but prior to the inlet of any control device that
is present, prior to any dilution of the process vent stream, and prior
to release to the atmosphere.
(1) Method 1 or 1A of 40 CFR part 60, appendix A, as appropriate,
shall be used for selection of the sampling site.
(2) No traverse site selection method is needed for vents smaller
than 0.10 meter in diameter.
(b) To demonstrate that a process vent stream flow rate is less
than 0.005 standard cubic meter per minute in accordance with the Group
2 process vent definition of this subpart, the owner or operator shall
measure flow rate by the following procedures:
(1) The sampling site shall be selected as specified in paragraph
(a) of this section.
(2) The gas volumetric flow rate shall be determined using Method
2, 2A, 2C, or 2D of 40 CFR part 60, appendix A, as appropriate.
(c) Each owner or operator seeking to demonstrate that a process
vent stream has an organic HAP concentration below 50 parts per million
by volume in accordance with the Group 2 process vent definition of
this subpart shall measure either total organic HAP or TOC
concentration using the following procedures:
(1) The sampling site shall be selected as specified in paragraph
(a) of this section.
(2) Method 18 or Method 25A of 40 CFR part 60, appendix A shall be
used to measure concentration; alternatively, any other method or data
that has been validated according to the protocol in Method 301 of
appendix A of this part may be used.
(3) Where Method 18 of 40 CFR part 60, appendix A is used, the
following procedures shall be used to calculate parts per million by
volume concentration:
(i) The minimum sampling time for each run shall be 1 hour in which
either an integrated sample or four grab samples shall be taken. If
grab sampling is used, then the samples shall be taken at approximately
equal intervals in time, such as 15 minute intervals during the run.
(ii) The concentration of either TOC (minus methane and ethane) or
organic HAP shall be calculated according to paragraph (c)(3)(ii)(A) or
(c)(3)(ii)(B) of this section as applicable.
(A) The TOC concentration (CTOC) is the sum of the
concentrations of the individual components and shall be computed for
each run using the following equation:
TR22AP94.201
where:
CTOC=Concentration of TOC (minus methane and ethane), dry basis,
parts per million by volume.
Cji=Concentration of sample component j of the sample i, dry
basis, parts per million by volume.
n=Number of components in the sample.
x=Number of samples in the sample run.
(B) The total organic HAP concentration (CHAP) shall be
computed according to the equation in paragraph (c)(3)(ii)(A) of this
section except that only the organic HAP species shall be summed. The
list of organic HAP's is provided in table 2 of subpart F of this part.
(4) Where Method 25A of 40 CFR part 60, appendix A is used, the
following procedures shall be used to calculate parts per million by
volume TOC concentration:
(i) Method 25A of 40 CFR part 60, appendix A shall be used only if
a single organic HAP compound is greater than 50 percent of total
organic HAP, by volume, in the process vent stream.
(ii) The process vent stream composition may be determined by
either process knowledge, test data collected using an appropriate EPA
method or a method or data validated according to the protocol in
Method 301 of appendix A of this part. Examples of information that
could constitute process knowledge include calculations based on
material balances, process stoichiometry, or previous test results
provided the results are still relevant to the current process vent
stream conditions.
(iii) The organic HAP used as the calibration gas for Method 25A of
40 CFR part 60, appendix A shall be the single organic HAP compound
present at greater than 50 percent of the total organic HAP by volume.
(iv) The span value for Method 25A of 40 CFR part 60, appendix A
shall be 50 parts per million by volume.
(v) Use of Method 25A of 40 CFR part 60, appendix A is acceptable
if the response from the high-level calibration gas is at least 20
times the standard deviation of the response from the zero calibration
gas when the instrument is zeroed on the most sensitive scale.
(vi) The owner or operator shall demonstrate that the concentration
of TOC including methane and ethane measured by Method 25A of 40 CFR
part 60, appendix A is below 25 parts per million by volume to be
considered a Group 2 vent with an organic HAP concentration below 50
parts per million by volume and to qualify for the low concentration
exclusion in Sec. 63.113(g) of this subpart.
(d) To determine the TRE index value, the owner or operator shall
conduct a TRE determination and calculate the TRE index value according
to the procedures in paragraph (d)(1) or (d)(2) of this section and the
TRE equation in paragraph (d)(3) of this section.
(1) Engineering assessment may be used to determine process vent
stream flow rate, net heating value, TOC emission rate, and total
organic HAP emission rate for the representative operating condition
expected to yield the lowest TRE index value.
(i) If the TRE value calculated using such engineering assessment
and the TRE equation in paragraph (d)(3) of this section is greater
than 4.0, then the owner or operator is not required to perform the
measurements specified in paragraph (d)(2) of this section.
(ii) If the TRE value calculated using such engineering assessment
and the TRE equation in paragraph (d)(3) of this section is less than
or equal to 4.0, then the owner or operator is required to perform the
measurements specified in paragraph (d)(2) of this section for group
determination or consider the process vent a Group 1 vent and comply
with the emission reduction specified in Sec. 63.113(a) of this
subpart.
(iii) Engineering assessment includes, but is not limited to, the
following:
(A) Previous test results provided the tests are representative of
current operating practices at the process unit.
(B) Bench-scale or pilot-scale test data representative of the
process under representative operating conditions.
(C) Maximum flow rate, TOC emission rate, organic HAP emission
rate, or net heating value limit specified or implied within a permit
limit applicable to the process vent.
(D) Design analysis based on accepted chemical engineering
principles, measurable process parameters, or physical or chemical laws
or properties. Examples of analytical methods include, but are not
limited to:
(1) Use of material balances based on process stoichiometry to
estimate maximum organic HAP concentrations,
(2) Estimation of maximum flow rate based on physical equipment
design such as pump or blower capacities,
(3) Estimation of TOC or organic HAP concentrations based on
saturation conditions,
(4) Estimation of maximum expected net heating value based on the
stream concentration of each organic compound or, alternatively, as if
all TOC in the stream were the compound with the highest heating value.
(E) All data, assumptions, and procedures used in the engineering
assessment shall be documented.
(2) Except as provided in paragraph (d)(1) of this section, process
vent stream flow rate, net heating value, TOC emission rate, and total
organic HAP emission rate shall be measured and calculated according to
the procedures in paragraphs (d)(2)(i) through (d)(2)(v) of this
section and used as input to the TRE index value calculation in
paragraph (d)(3) of this section.
(i) The vent stream volumetric flow rate (Qs), in standard
cubic meters per minute at 20 deg.C, shall be determined using Method
2, 2A, 2C, or 2D of 40 CFR part 60, appendix A, as appropriate. If the
vent stream tested passes through a final steam jet ejector and is not
condensed, the stream volumetric flow shall be corrected to 2.3 percent
moisture.
(ii) The molar composition of the process vent stream, which is
used to calculate net heating value, shall be determined using the
following methods:
(A) Method 18 of 40 CFR part 60, appendix A to measure the
concentration of each organic compound.
(B) American Society for Testing and Materials D1946-77 to measure
the concentration of carbon monoxide and hydrogen.
(C) Method 4 of 40 CFR part 60, appendix A to measure the moisture
content of the stack gas.
(iii) The net heating value of the vent stream shall be calculated
using the following equation:
TR22AP94.202
where:
HT=Net heating value of the sample, megaJoule per standard cubic
meter, where the net enthalpy per mole of vent stream is based on
combustion at 25 deg.C and 760 millimeters of mercury, but the
standard temperature for determining the volume corresponding to one
mole is 20 deg.C, as in the definition of Qs (vent stream flow
rate).
Kl=Constant, 1.740 x 10-7 (parts per million)-1 (gram-
mole per standard cubic meter) (megaJoule per kilocalorie), where
standard temperature for (gram-mole per standard cubic meter) is 20
deg.C.
Bws=Water vapor content of the vent stream, proportion by volume;
except that if the vent stream passes through a final steam jet and is
not condensed, it shall be assumed that Bws=0.023 in order to
correct to 2.3 percent moisture.
Cj=Concentration on a dry basis of compound j in parts per
million, as measured for all organic compounds by Method 18 of 40 CFR
part 60, appendix A and measured for hydrogen and carbon monoxide by
American Society for Testing and Materials D1946-77 as indicated in
paragraph (d)(2)(ii) of this section.
Hj=Net heat of combustion of compound j, kilocalorie per gram-
mole, based on combustion at 25 deg.C and 760 millimeters mercury. The
heats of combustion of vent stream components shall be determined using
American Society for Testing and Materials D2382-76 if published values
are not available or cannot be calculated.
(iv) The emission rate of TOC (minus methane and ethane)
(ETOC) and the emission rate of total organic HAP (EHAP) in
the vent stream shall both be calculated using the following equation:
TR22AP94.203
where:
E=Emission rate of TOC (minus methane and ethane) or emission rate of
total organic HAP in the sample, kilograms per hour.
K