[Federal Register Volume 61, Number 47 (Friday, March 8, 1996)]
[Proposed Rules]
[Pages 9383-9399]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-5397]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 63
[AP-FRL-5437-6]
RIN 2060-AE04
National Emission Standards for Hazardous Air Pollutants for
Source Category: Pulp and Paper Production
AGENCY: Environmental Protection Agency (EPA).
ACTION: Announcement of availability of supplemental information,
proposed rule, and opening of the public comment period for these
actions.
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SUMMARY: This action presents an assessment of supplemental information
on 1993 proposed National Emission Standards for Hazardous Air
Pollutants (NESHAP) for the Pulp and Paper Production Source Category
and announces proposed additional sources in that source category not
covered by the 1993 proposed standards. These additional sources
include mechanical mills, secondary fiber mills, nonwood fiber mills,
and paper machines. This action also announces availability of data for
public review that is in addition to data previously announced in a
February 22, 1995 Notice of Data Availability (60 FR 9813). In
addition, this action announces the availability and requests comments
on new emission factors developed using that data.
This action sets forth the most significant changes EPA is
considering, but is not inclusive of all changes likely
[[Page 9384]]
to be made on the 1993 proposed NESHAP. EPA is still considering other
comments submitted on the 1993 proposed NESHAP and will combine them
along with comments and data received on this action to form the basis
for the promulgation of a final NESHAP later this year. Proposed NESHAP
for the chemical recovery area combustion sources at mills are not
contained in this action, but will follow in a separate action later
this year.
DATES: Comments are requested only on information presented in this
action. Comments must be received on or before April 8, 1996, unless a
public hearing is requested by March 18, 1996. If a hearing is
requested, written comments must be received by April 22, 1996.
ADDRESSES: Comments related to the chemical wood pulping mills (kraft,
sulfite, soda, and semi-chemical) should be submitted (in duplicate, if
possible) to: Air Docket Section (6102), Attn: Docket No. A-92-40, U.S.
EPA, 401 M Street, SW, Washington, DC 20460, and Ms. Penny Lassiter,
address shown in FOR FURTHER INFORMATION CONTACT Section. Comments
related to mechanical mills, secondary fiber mills, nonwood mills, and
paper machines should be submitted (in duplicate, if possible) to Air
Docket Section (6102), Attn: Docket No. A-95-31 (MACT III), U.S. EPA,
401 M Street, SW, Washington, DC 20460 and Ms. Elaine Manning, address
shown in FOR FURTHER INFORMATION CONTACT Section.
FOR FURTHER INFORMATION CONTACT: For additional information or
regulations applicable to chemical wood pulping mills, contact Ms.
Penny Lassiter or Mr. Stephen Shedd, Office of Air Quality, Planning,
and Standards (MD-13), U.S. EPA, Research Triangle Park, North Carolina
27711: telephone Ms. Lassiter at (919) 541-5396 or Mr. Shedd at (919)
541-5397. For further information on the regulatory development for
mechanical mills, secondary fiber mills, nonwood mills, and paper
machines, contact Ms. Elaine Manning at the address in Research
Triangle Park listed above, telephone (919) 541-5499, facsimile for the
address in Research Triangle Park listed above is (919) 541-3470.
SUPPLEMENTARY INFORMATION: Public Hearing. Anyone requesting a public
hearing must contact EPA no later than March 18, 1996. If a hearing is
held, it will take place on March 25, 1996, beginning at 9 a.m. at the
EPA Administration Bldg., Main Auditorium, 79 T.W. Alexander Drive,
(near intersection of NC54), Research Triangle Park, NC. Persons
interested in attending the hearing or wishing to present oral
testimony should notify Ms. Jolynn Collins, U.S. EPA, Research Triangle
Park, North Carolina 27711, telephone (919) 541-5671.
Docket. Air Docket No. A-92-40, contains supporting information
used in developing the proposed standards and this action for the
chemical wood pulping mills. All docket cites in this action are from
Air Docket No. A-92-40, unless specified differently. Air Docket No. A-
95-31 contains information that supports the proposed standards for the
rule development for the mechanical mills, secondary fiber mills,
nonwood mills and paper machines. These air dockets are located at the
U.S. Environmental Protection Agency, 401 M Street, SW, Washington, DC
20460 in room M-1500, Waterside Mall (ground floor). All comments
received during the public comment period on the 1993 proposed NESHAP
are contained in the Pulp and Paper Water Docket located in the
basement of Waterside Mall, room L102. These dockets may be inspected
from 8:30 a.m. to 12 p.m. and 1:00 p.m. to 3:00 p.m., Monday through
Friday. A reasonable fee may be charged for copying.
Documents. An electronic version of this action as well as ``Review
Draft: Chemical Pulping Emission Factor Development Document,''
``Presumptive MACT for Non-Chemical and Other Pulp and Paper (MACT III)
Mills,'' and previous Federal Register notices pertinent to the pulp
and paper NESHAP are available for download from EPA's Technology
Transfer Network (TTN), which is a network of electronic bulletin
boards developed and operated by EPA's Office of Air Quality Planning
and Standards. The TTN provides information and technology exchange in
various areas of air pollution control. The service is free, except for
the cost of a phone call. Dial (919) 541-5742 for data transfer of up
to 14,400 bits per second. The TTN is also available on the Internet
(access: TELENET ttnbbs.rtpnc.epa.gov). For more information on the
operation of the TTN, contact the systems operator at (919) 541-5384.
The information in this action is organized as follows:
I. Background
A. History
B. Summary of Action
C. New Data
D. Public Participation
II. Source Category and Pollutants for Control
III. Emission Factors
IV. Definition of Source
V. Subcategorization
VI. Level of Standards
A. Kraft
B. Sulfite
C. Semi-Chemical
D. Soda
E. Bleaching
VII. Compliance Extension for Kraft Mills
VIII. Emission Averaging
IX. Relationship with Other Rules
A. New Source Review/Prevention of Significant Deterioration
Applicability
B. Boiler/Industrial Furnace/Resource Conservation and Recovery
Act Applicability
C. Kraft New Source Performance Standards
X. Standard for Nonchemical Pulp Mills
A. Presumptive MACT Process
B. Summary of the Presumptive MACT for MACT II Sources
C. Area/Major Source Discussion
D. Proposed MACT III
E. Request for Information
I. Background
A. History
The Clean Air Act (the Act) requires EPA to develop NESHAP for the
pulp and paper source category by November 1997. Under section 112 (d)
of the Act, the goal of NESHAP is to require the implementation of
maximum achievable control technology (MACT) to reduce emissions and,
therefore, reduce the public health hazard of pollutants emitted from
stationary sources.
On December 17, 1993 (58 FR 66078), EPA published proposed NESHAP
and effluent guidelines for the pulp and paper industry. These
integrated regulations are referred to as the cluster rule. The purpose
of this action is to announce the availability of additional data and
to reopen the public comment period only for items identified in this
action. EPA's Office of Water (OW) plans to issue a Federal Register
notice similar to this action for the effluent guidelines portion of
the cluster rule. Publication of OW's action is anticipated to be in
approximately four weeks.
The 1993 proposed air standards would regulate all HAP's emitted
from new and existing pulp and paper mills that chemically pulp wood
fiber using kraft, sulfite, soda, or semi-chemical methods (MACT I).
These proposed MACT I standards address air emission points in the
pulping and bleaching processes and in the associated process
wastewater collection and treatment systems. Information was not
available at that time to evaluate controls on other emission points
within the source category. The standards for the pulp and paper source
category, therefore, are being developed in phases. Standards for
combustion sources (MACT II) are under development and will be proposed
later this year. Proposed standards for the remaining sources
[[Page 9385]]
(MACT III) are addressed in Section X of this notice. The MACT III
standards apply to the following operations located at all mills:
mechanical pulping (e.g., groundwood, thermomechanical, pressurized);
pulping of secondary fibers (deinked and nondeinked) by nonchemical
means; nonwood pulping; and paper machine additives. Coating and
converting operations will be addressed later under a separate source
category.
Available data shows that pulp and paper facilities emit
significant quantities of HAP's that would be controlled by the
proposed standards. Some of these pollutants are considered to be
carcinogenic, and all can cause toxic health effects following
exposure, including nausea, headaches, respiratory distress, and
possible reproductive effects. Most of the organic HAP's emitted from
this industry also are classified as volatile organic compounds (VOC)
which participate in photochemical reactions in the atmosphere to
produce ozone, a contributor to photochemical smog. The proposed
emission controls for HAP's will reduce VOC emissions as well. The
proposed HAP control technologies will similarly reduce emissions of
total reduced sulfur (TRS) compounds that are of concern because they
produce some odor and they include some HAP.
The public comment period on the proposed NESHAP ended on April 18,
1994; however, EPA recognized in the preamble to the proposed rule that
various industry groups were collecting air emissions data that would
not be available until after the comment period and further stated that
EPA would still consider those data before the promulgation of the
NESHAP. Some of the data were received and were noticed in a February
22, 1995 Notice of Data Availability (60 FR 9813).
This action announces the availability of new data and solicits
comments on the use of the data for emission factor development and on
changes to the proposed rule. These data and analyses are included in
Air Docket A-92-40. This action does not reopen the public comment
period for all issues related to the proposed rule. Comments should
address only those technical and regulatory changes specifically
mentioned in this action.
On September 29, 1995, a Presumptive MACT report was issued for the
MACT III source category. A brief description of the Presumptive MACT
process and the outcome of the process is provided in Section X.
Comments are also solicited on the MACT III tentative conclusions. EPA
currently plans to take final action on the MACT III NESHAP for the
sources discussed in this action at the same time as the MACT I final
action. EPA also plans to propose NESHAP for recovery area combustion
sources (MACT II) at the same time.
B. Summary of Action
As noted earlier, EPA has proposed NESHAP for mills that chemically
pulp wood fiber. EPA is considering revisions to this proposed NESHAP
based on comments from the public as well as test data that has been
given to EPA since proposal. The changes to the proposed rule under
consideration include: revisions to emission factors; broadening of the
source definition; development of subcategories for pulping; revisions
to MACT requirements and how they are applied; and revisions to MACT
compliance schedule for certain kraft mill emission points. This action
also identifies how EPA currently plans to address concerns raised by
commentors regarding interaction between the NESHAP, currently under
development and other rules, such as Resource Conservation and Recovery
Act/Boiler Industrial Furnace (RCRA/BIF) and Prevention of Significant
Deterioration/New Source Review (PSD/NSR). EPA is also soliciting
comments on the industry's alternative compliance concept that includes
some degree of emissions averaging. A brief overview of these changes
is described below. The data and information to support these changes
under consideration can be found in the Air Docket No. A-92-40.
Additionally, EPA is announcing a proposed decision for standards for
other mills and paper machines.
The emission factors were evaluated using additional emission test
data submitted by the industry. Also, the approach to emission factor
development has changed since proposal as more information has become
available. The new approach involves developing emission factors for
functional mill systems, as opposed to the individual emission points
used at proposal. This emission factor evaluation is contained in a
development document and is being announced in this notice for public
review and comment.
At proposal, EPA chose a single source definition to include
pulping processes, bleaching processes, and pulping and bleaching
wastewater streams at a pulp and paper mill. EPA currently intends to
expand this definition to include paper machines and the causticizing
area due to the interrelated nature of these processes with the pulping
and bleaching areas.
At this time, EPA plans to subcategorize the pulping and associated
wastewater components to develop different MACT requirements. This
subcategorization is necessary to reflect important differences between
the different pulping process emissions, emission controls, and control
cost. The pulping (and associated wastewater) subcategories being
considered are kraft, sulfite, soda, and semi-chemical.
At proposal, all vents and pulping wastewater streams in pulping
and bleaching areas were subject as a group to the MACT requirements
with the exception of certain small vents and wastewater streams
defined by numerical cutoffs. For existing source MACT applicable to
the pulping component at kraft mills, EPA is considering specifically
defining the following systems as requiring enclosure and venting to a
control device: the low volume-high concentration (LVHC) vent system
(i.e., the digester, turpentine recovery, and evaporator systems); weak
black liquor storage tanks; the pre-washer knotting and screening
system; the brownstock washing system; and the oxygen delignification
system. Enclosure and vent control requirements would not change from
proposal. Only these enumerated systems would be subject to the rule.
EPA currently intends to define new source MACT for the pulping
area at kraft mills to be the same as existing source MACT with the
addition of control of post-washer deckers and screens. EPA currently
intends to define new and existing source MACT for kraft mill
wastewater to be collection and treatment of certain named pulping
condensate streams instead of all pulping wastewater above 500 parts
per million by weight (ppmw). EPA is considering changing the proposed
treatment requirements for steam strippers at kraft mills to allow
compliance with one of the following: (1) Removal of 92 percent of the
HAP or methanol content, (2) removal of 9.2 pounds of methanol per air-
dried ton of pulp (lb/ADTP), or (3) treat to a steam stripper outlet
HAP concentration below 330 ppmw measured as methanol. For unbleached
kraft mills, the following treatment requirements would be applicable:
(1) Removal of 92 percent of the HAP or methanol content; (2) removal
of 5.9 lb/ADTP of methanol; or (3) treatment to a steam stripper outlet
HAP concentration below 210 ppmw measured as methanol. As at proposal,
methanol is being used here as a surrogate for tracking total HAP
reduced. Mills still have the option of achieving these removals with
an
[[Page 9386]]
alternative control device, recycling to a controlled system, or
hardpiping these condensate streams directly to the biological
wastewater treatment plant instead of steam stripping.
EPA is considering extending the compliance time for controlling
brownstock washers and oxygen delignification units for kraft pulping
mills by an additional 5 years. The additional period would be provided
to allow industry sufficient time to plan, coordinate, and implement
the best combination of control technologies that facilitate pollution
prevention and emphasize the multimedia nature of pollution control.
EPA is considering the following standards for the newly-created
sulfite, semi-chemical, and soda mill subcategories. Based on an
analysis of current controls, EPA is considering requiring certain
sulfite mill vents in the pulping component at existing sources (i.e.,
digester, evaporator, and red stock washers) to be vented to recovery
systems to reduce HAP emissions. Affected vents at new sources include
the same vents as at existing sources, with the addition of knotter and
screening systems, and weak and strong liquor and acid condensate
storage tank vents. Air emissions from these selected vents and
connected recovery systems would be limited to certain mass emission
rates or percent reductions across the complete connected system. This
systems approach would allow many mills to use the various
configurations of current recovery systems to meet either of these
limits. Compliance would be demonstrated by an initial performance test
to confirm compliance with one of the mass limits, followed by
monitoring of control and process equipment operating parameters to
demonstrate long-term compliance. EPA has determined from an evaluation
of the current mill emission data that the following emission values
represent the best performing existing and new mills: (1) Mass emission
rates of 0.65 and 1.10 lb methanol/ODTP, or (2) a mass HAP or methanol
emission reduction of 92 and 87 percent, for calcium-based and ammonium
and magnesium-based mills, respectively. The new and existing MACT for
pulping wastewater streams at sulfite mills would be no additional
control.
EPA currently plans to define existing source MACT for semi-
chemical mills and soda mills to be enclosure and venting of LVHC vents
to a control device. Enclosure and control device requirements would be
the same as at proposal. New source MACT for semi-chemical and soda
mills would be the same as existing source MACT plus the control of the
washer system vents. The new and existing MACT for pulping wastewater
streams at semi-chemical and soda mills is no additional control.
For bleaching processes at all mills, EPA is still considering
requiring all vents from the bleaching stages which utilize chlorine
and/or chlorine dioxide to control emissions of chlorinated HAP's by 99
percent from the tower, seal tank, and washer vents as in the proposed
NESHAP. A new limit of 10 parts per million by volume (ppmv) of
chlorinated HAP from the outlet of the scrubber is also now being
considered as an alternative to the 99 percent removal limit. A mill
would still be allowed to measure the chlorinated HAP's as chlorine.
Additionally paper-grade bleaching processes would be required to
control chloroform air emissions by complying with the Best Available
Technology (BAT) economically achievable currently under development by
EPA's OW. EPA is still re-considering the level of control for
chloroform from bleach plants at dissolving-grade mills. MACT for new
sources would be the same as MACT for existing sources. The proposed
requirements for controlling methanol and other organic HAP emissions
for bleaching stages will likely no longer be considered. As at
proposal, MACT for bleaching wastewater would be no additional control.
EPA has responded to requests for guidance on the interaction and
applicability of the proposed air regulation with RCRA/BIF and NSR/PSD.
With regard to the possible interaction of the regulation with RCRA/BIF
that could result from the combustion of concentrated condensates
derived from steam stripper overhead vents, EPA has initially
determined that regulation of combustion of these condensates under
RCRA is unnecessary because the MACT controls would be protective. With
regard to the possible interaction of the regulation with NSR/PSD that
could come as a result of secondary emissions from combustion control
devices used to comply with this NESHAP, EPA is considering
recommending to State permitting agencies that mills complying with the
cluster rule be granted the ``pollution control project'' (PCP)
exclusion and be allowed to conduct minor NSR only.
These are the most significant changes to the 1993 proposal that
EPA may implement in the final NESHAP, but they do not include all
changes likely to be made. More detailed information on changes
discussed in this action and supporting documentation can be found in
later sections.
In this action, EPA is also announcing a proposed decision for
standards for mechanical mills, secondary fiber mills, nonwood mills,
and additives and solvents applied to paper machines (MACT III). The
proposal is based on Presumptive MACT that was issued in September
1995.
C. New Data
In the February 22, 1995 Notice of Data Availability (60 FR 9813),
EPA announced data that had been received through February 16, 1995.
These data included three separate multi-volume test reports, several
test report and testing program summaries, and a draft condensate
study. This action announces the availability of new data and solicits
comments on the use of the data for emission factor development and on
changes to the proposed rule.
Data added to Air Docket A-92-40 since the 1993 proposal are
located in Section IV of this docket. Major groups of data of
particular note (but not inclusive of all data in Section IV under
consideration by EPA) are as follows: (1) Items IV-A-4, IV-D1-30, IV-
D1-32, IV-D1-36, IV-J-17, and IV-J-28, supplemental information and
corrections to the data noticed at 60 FR 9813; (2) IV-D1-84 and IV-J-
31, compilation of emissions data noticed at 60 FR 9813; (3) items IV-
D1-27, IV-D1-46, IV-D1-66, IV-D1-75, and IV-D1-79, wastewater system
components, emissions, methanol biodegradability in wastewater
treatment systems, and soluble biological oxygen demand (BOD) as a
parameter to track methanol biodegradability; (4) IV-D1-72, IV-D1-76,
IV-D1-77, IV-D1-80, IV-D1-81, IV-D1-86, IV-D1-89, IV-D1-90, IV-D1-92,
IV-E-64, and IV-E-68, control of air emissions at semi-chemical pulp
mills; (5) IV-D1-87, IV-D1-88, IV-D-93, IV-D1-94, IV-E-31b, IV-E-60,
IV-E-66, and IV-E-67, control of air emissions at sulfite pulp mills;
(6) IV-D1-43, IV-D1-58, IV-D1-62, IV-E-15, IV-E-25, IV-E-28, IV-E-38,
IV-E-45, and IV-J-9, control design and costs; (7) IV-J-29 and IV-J-32,
characterization of pulping condensates; (8) IV-D1-59 and IV-D1-95,
industry's Clean Water Alternative (see Section VIII of this notice);
(9) IV-D1-83, knotter emissions data; and (10) IV-D1-51, IV-D1-56, and
IV-E-63, characterization and control of concentrated steam stripper
condensates.
EPA also requests comments on EPA studies and memoranda completed
since the 1993 proposal and contained in the docket (docket categories
IV-A EPA Studies or Contractor Reports and IV-B EPA Factual Memoranda).
These EPA studies and memoranda include
[[Page 9387]]
the emission factor development document and provide support material
for the Level of the Standards Section VI in this notice.
D. Public Participation
A public comment period was open from December 17, 1993 to April
18, 1994 and a public hearing was held on February 10, 1994 to receive
comments on the 1993 proposal. Comments and data received at the
hearing and during the comment period are included in the docket (see
SUPPLEMENTARY INFORMATION Section). EPA has also held numerous meetings
on the 1993 proposed integrated rules and the Presumptive MACT with
many of the stakeholders from the pulp and paper industry, including a
trade association (American Forest and Paper Association - AF&PA),
numerous individual companies, consultants and vendors, environmental
groups, labor unions, and other interested parties. Materials have been
added to the docket to document these meetings and to make available
for public review new information received at those meetings.
II. Source Category and Pollutants for Control
EPA proposed in 1993 to regulate total HAP emissions from mills
that chemically pulp wood fiber using kraft, sulfite, soda, and semi-
chemical methods. At that time, EPA did not propose to regulate the HAP
emissions from other types of mills. EPA is now inclined to include
into this standard additional types of mills in the pulp and paper
industry as well as the paper machines at all the mills (MACT III).
These new mills include mechanical mills, secondary fiber mills, and
nonwood mills. EPA's current position on these mills and on paper
machines is described in Section X.
The 1993 proposed NESHAP regulates total HAP emissions from
pulping, bleaching, and process wastewater at facilities covered by the
proposal, as opposed to individual HAP's. The proposed standards allow
the use of methanol (or methanol and chlorine from bleaching emissions)
as surrogate compounds because EPA initially concluded that use of
surrogates is technically viable and is a less costly way to track HAP
emission reductions.
For pulping processes and wastewater, EPA's position on pollutants
to be covered has not changed since proposal, and EPA is still inclined
to regulate total HAP emissions, allowing the use of methanol as a
surrogate measurement parameter. At proposal, EPA determined that the
bleach plant emissions were comprised of various chlorinated and
nonchlorinated HAP's. Therefore, a total HAP standard was proposed.
Data at proposal indicated that methanol and chlorine could be used as
surrogates for the nonchlorinated and chlorinated portions of total
HAP, respectively. As a result of comments and data received since
proposal, EPA now knows that only chlorinated HAP's, primarily
chlorine, chloroform, and hydrochloric acid, are being controlled by
the MACT control technologies for bleach plant emissions. Therefore,
EPA currently plans to regulate only the emissions of chlorinated HAP's
from bleaching processes. A more detailed discussion on this topic is
presented in Section VI.
III. Emission Factors
Based on comments and data received, EPA has re-evaluated the
emission factor development approach used to characterize emission
sources and developed new emission factors. EPA developed emission
factors at proposal based on all available data. These data included a
field test program of air and liquid samples from four kraft mills and
one sulfite mill (EPA 5-mill study) and some limited additional
industry data that was used to supplement EPA 5-mill study (see the
Pulp, Paper, and Paperboard Industry Background Information for
Promulgated Standards, Volume 2). Industry representatives commented
that these data were insufficient to accurately characterize emissions
and have since supplied EPA with additional test data from kraft,
sulfite, semi-chemical, and soda mills. EPA analyzed and incorporated
these data into the existing database.
At proposal, EPA developed emission factors for each type of
individual emission point typically found at the mills. Based on the
additional test data, EPA is considering changing that approach. The
new approach involves developing emission factors based on mill systems
rather than on individual emission points. The mill systems are defined
in Section VI, Level of Standards.
EPA now considers this mill system approach the best approach for
several reasons. First, this approach provides a more objective
comparison of the mills. Mills often utilize different configurations
of equipment within a system, making point by point comparisons
misleading. Averaging such pieces of equipment together can provide an
inaccurate estimate of the total system. For example, comparing one
mill's oxygen delignification system as a whole to another mill's
system was more meaningful than establishing separate emission factors
for each piece in the system (e.g., blow tanks, washer units,
interstage storage chests, and filtrate tanks); not all mills have the
same types of equipment in their oxygen delignification system, and
some mills label their oxygen delignification equipment differently.
Next, one mill may have a single screen and another mill may have
multiple screens, but both mills have one screening system with
emissions that can be compared. The mill system approach makes these
kinds of comparisons between mills possible.
Finally, the mill system approach lessens the problems associated
with the nomenclature assigned to each of the components. Variability
exists between the names that different mills assign to similar pieces
of equipment in the same locations. By combining individual emission
points into complete systems, the problem was lessened.
The results and the grouping procedures and approach followed for
each mill system at the various mill types are detailed in the ``Review
Draft: Chemical Pulping Emission Factor Development Document.'' The
report is available in the docket and may be downloaded from the TTN
(see SUPPLEMENTARY INFORMATION Section). This report also discusses the
specific issues and all assumptions that were made in the emission
factor development, including the specific data points tested by
industry that were included in each mill system. EPA is specifically
asking for comments on the results and the approach used in developing
the emission factors before issuing the final report.
IV. Definition of Source
In the December 17, 1993 proposal, three definitions of ``source''
were proposed and considered by EPA. The one chosen by EPA at the time
of proposal was a single source to include the pulping processes, the
bleaching processes, and the pulping and bleaching process wastewater
streams at a pulp and paper mill. EPA is still inclined to use the
single source definition. EPA considers the broad source definition to
be the best interpretation for the pulp and paper industry. This broad
source definition would alleviate concerns that a small change to an
existing mill that creates a small increase in emissions would trigger
new source requirements in the NESHAP. The single source definition is
also the most appropriate interpretation for the industry due to the
interrelated nature of equipment in pulp and paper mills. For example,
wastewater recycling from process to process is an
[[Page 9388]]
integral part of a mill in order to reduce fresh water intake.
Emissions from a piece of process equipment are a function of
pollutants released during the processing of the pulp as well as
pollutants volatilized from water recycled to the process equipment.
EPA is inclined to include paper machines and causticizing
equipment in the source definition above. The term paper machine being
used here does not include paper machine additives and solvents, and
their associated air emissions being addressed in the proposed MACT III
standards set forth in Section X of this notice. Paper machine
emissions discussed here for inclusion in the above source definition
are from the HAP's remaining on the pulp from the pulping and bleaching
process and released when processed through the paper machine. EPA
would include paper machines and causticizing equipment since the
emissions from these sources are, like the emission points discussed
above, interrelated with other process emissions. For example, water is
often reused or recycled from pulping processes to the causticizing
processes, and HAP's in the pulp and water slurry from the pulping and
bleaching processes are carried over into the paper machine where they
are emitted. While the causticizing area and the paper machines were
not defined as part of the source at proposal, they were still being
controlled through the wastewater MACT requirements. Treatment of
condensate streams to remove HAP's prior to recycling them would result
in reduced emissions from the equipment to which they are recycled and
from subsequent pieces of equipment due to reductions in HAP carried
over with the pulp and process waters. EPA recognizes the wastewater
contribution to emissions from these processes and as such currently
intends to include these processes in the source definition. A mill
could then take credit for emission reductions from these processes if
it chose to implement the Clean Water Alternative. The Clean Water
Alternative is discussed further in Section VIII (Emissions Averaging).
EPA considered regulating emissions from woodpiles, but did not
find evidence to suggest that woodpiles are sources of HAP emissions.
Therefore, they are excluded from the definition of source.
V. Subcategorization
In the proposed rule, EPA solicited comment on the need for
subcategories. Many commentors responded to this solicitation with
information on why certain mills should be treated differently than
kraft mills. Separate subcategories for kraft, sulfite, soda, and semi-
chemical pulping processes were suggested. Issues raised by commentors
in support of subcategories included the difference in process
emissions and emission control technologies for sulfite, soda, and
semi-chemical mills. Others indicated that the lack of air and
wastewater emissions data on these types of mills prevented a balanced
assessment of the need for subcategories.
Based on comments received, review of the industry data submitted
after proposal, and meetings with industry groups, EPA solicits comment
on establishing four separate subcategories for the pulping processes
at mills based on the type of pulping process (kraft, sulfite, semi-
chemical, and soda) used.
As a result of the differences in digestion methods, the mills
produce different emissions that have resulted in different degrees of
control at baseline and different applicable control technologies. At
proposal, EPA understood that the four types of mills differ in the way
they digest wood to make pulp, but did not have the data to determine
the extent to which these differences influence potential emission
control strategies. Information received after proposal indicated the
significant extent of these differences.
Kraft mills generate significant quantities of TRS compounds.
Emissions of TRS compounds are regulated under the New Source
Performance Standards for Kraft Mills (kraft NSPS). The vent streams
subject to control also contain HAP's. Therefore, a number of kraft
mills already have a control system in place for the LVHC vent streams.
Also, most kraft mills contain the means of combusting other HAP
containing streams, such as high volume-low concentration (HVLC) vent
streams.
While the HAP-containing vents at kraft mills are laden with TRS
compounds, the HAP containing vents at sulfite mills contain sulfur
dioxide (SO2). Sulfite mills collect the emissions from these
vents to recover the SO2, which is necessary to the production of
the cooking liquor. The collection and burning of these vent streams,
as is typically done at kraft mills, would not be practical. Therefore,
a MACT standard with a different technology basis is needed for these
mills, and a separate subcategory warranted.
Emissions data indicate that soda and semi-chemical mills have HAP
emissions in the same range as for kraft mills, although semi-chemical
mill emissions tend to be at the lower end of the kraft range. However,
these mills do not generate significant quantities of TRS compounds.
Therefore, these mills lack the LVHC equipment already installed at
kraft mills, as well as lacking the benefit of controlled odor from
these vent streams. The digestion process in semi-chemical pulping
differs from soda pulping resulting in different emission points and
characteristics. However, EPA intends to set MACT for the semi-chemical
and soda mills as control of the LVHC vent streams. The MACT
requirements are discussed in Section VI (Level of Standards).
Where two or more subcategories are located at the same mill site
and share a piece of equipment, that piece of equipment would be
considered a part of the subcategory with the more stringent MACT
requirements for that piece of equipment. For example, the foul
condensates from an evaporation set processing both kraft weak black
liquor and spent liquor from a semi-chemical process would have to
comply with the kraft subcategory requirements for foul condensate.
This more stringent requirement is appropriate because there is no
viable way to isolate the emissions for each pulping source to
determine compliance separately.
VI. Level of Standards
Changes from the 1993 proposal now being considered by EPA on the
level of the standard (emission limits and points to be controlled) are
presented in this section. At proposal, sulfite, semi-chemical, and
soda mills were not differentiated from kraft pulping mills and
therefore were subject to the same control requirements as kraft mills.
As discussed earlier, EPA is considering subcategorizing kraft,
sulfite, semi-chemical, and soda pulping and associated wastewater
components for the purpose of setting MACT standards. While EPA does
not currently contemplate subcategorizing among bleaching processes,
EPA may distinguish between papergrade and dissolving grade bleaching
processes for purposes of setting chloroform MACT requirements for
bleach plants. The rationale for this distinction is set forth later in
this section.
EPA is also considering naming specific vents and streams subject
to the standard instead of determining affected emission points and
wastewater streams based on broad groups of equipment with exclusions
for small streams currently not being controlled, as was done at
proposal. This change in approach will more accurately specify the
units that should be controlled.
Requirements for enclosures, closed-vent systems, and control
devices for
[[Page 9389]]
those closed vent systems in the pulping process, as set forth in the
proposed NESHAP, would be the same for the pieces of equipment being
named in this action for kraft, semi-chemical, and soda mills. Public
comments received on these 1993 proposed NESHAP requirements are under
review. EPA will consider these comments prior to promulgation of this
rule and will assess whether changes are warranted; however, such
potential changes are not discussed in this notice. Those same
requirements for enclosures and closed-vent systems, as set forth in
the proposed NESHAP, would also apply to the pieces of equipment being
named in this action for sulfite mills; however, EPA is considering
changing the control device requirements for those closed vent systems
at sulfite mills. Requirements for control of emissions from kraft
pulping wastewater prior to treatment, as set forth in the 1993
proposal, would still apply to the kraft pulping condensate streams
being named in this action; however, EPA is considering changing the
treatment limits for these pulping condensates. No control requirements
are now being considered for non-kraft wastewater streams. Requirements
for enclosures, closed-vent systems, and control devices for those
closed vent systems in the bleaching process, as set forth in the 1993
proposed NESHAP, would be the same for the stages using chlorinated
bleaching agents; however, EPA is considering adding some requirements
for the control of chloroform emissions and is considering adding
additional ways to meet the treatment requirements on the closed vent
systems from the chlorinated bleaching stages. Additionally, EPA is
considering dropping the requirement for control of non-chlorinated
HAP's (methanol, etc.) in the bleaching area.
A. Kraft
This section describes the changes to the level of the standard for
kraft mills from the 1993 proposal. These changes include naming the
streams to be controlled; changing and adding additional performance
levels for steam strippers; and re-evaluating controls for pre-washer
knotter and screen systems, and weak black liquor storage tanks.
The proposed standards required owners or operators of new or
existing sources to enclose and vent all pulping component emission
points into a closed vent system routed to a control device. Deckers
and screens at existing mills and small vents or enclosed process
equipment below certain specified volumetric flow rates, mass flow
rates, and mass loadings were not subject to control. Similarly,
pulping wastewater streams with concentrations below 500 ppmw of HAP's
or flow rates below 1.0 liter per minute (lpm) did not require control.
At proposal, EPA had limited data to characterize some of the
smaller emission points and condensate streams within the pulping
component. However, based upon experience and engineering assumptions,
these small vents and condensate streams were assumed to be
uncontrolled at the floor and not reasonable to control beyond the
floor. Therefore, EPA proposed these low volumetric flow rates and
condensate HAP concentrations to differentiate between points currently
being controlled and those that are not controlled. EPA solicited
comments on whether this was a viable approach for identifying emission
points and condensate streams that should be controlled under the MACT
standard.
Based on comments and data received, EPA re-evaluated the method
for establishing control applicability for pulping process equipment
and associated wastewater streams. Using this new information, EPA is
now tentatively intending to establish control applicability for kraft
pulping process equipment systems and associated wastewater streams by
specifically defining the equipment systems and associated wastewater
streams subject to the MACT standard (i.e., only the equipment systems
and wastewater streams specifically enumerated would be subject to the
standard). EPA believes this change will result in the same level of
control at the MACT floor for both wastewater and process equipment
contemplated in the proposal, yet will reduce or eliminate the cost of
testing that would have been required by the 1993 proposal to determine
applicability. The requirements for enclosures, closed vent systems,
and control devices set forth in the 1993 proposal would still apply.
The named pulping process systems that EPA is considering for
control are: the LVHC vent system, pre-washer knotter and screening
system, the brownstock washing system, weak black liquor storage tanks,
and the oxygen delignification system. The following new definitions
are now under consideration:
1. The LVHC vent system includes batch the digester blow heat
recovery vents, batch digester relief steam condenser vents, continuous
digester relief steam vents, turpentine condenser(s) vents, continuous
digest blow tank vent, evaporator vacuum system vents, liquor
concentrator vacuum system vents, pre-evaporator vacuum system vents,
steam stripper feed tank vents, and steam stripper off gas vents.
2. The brownstock washing system includes rotary vacuum drum
washers, pressure washers, diffusion washers, horizontal belt washers,
all filtrate tanks, and intermediate stock chests. The washing system
does not include deckers, screens, stock chests or pulp storage tanks
following the last stage of brownstock washing.
3. The oxygen delignification system includes the blow tank, the
post oxygen washers, filtrate tanks, and any interstage pulp storage
tanks.
4. The pre-washing screening system includes knotters, knotter
drain tanks, screens, and reject tanks prior to brownstock washing.
At proposal, EPA concluded that a sufficient number of weak black
liquor storage tanks are controlled in the industry to constitute a
floor-level of control. However, several commentors stated that weak
black liquor storage tanks could not feasibly be controlled by simply
venting the tanks to a header system and combustion device (the basis
for the 1993 proposal). The commentors stated that a more complex
system involving sweeping air across the tank would be necessary due to
the potential for an older tank to collapse if a vacuum were pulled on
the tank. A sweep air system would generate a larger volumetric flow
rate from these tanks and thus increase the size of the header and the
combustion capacity required of the control device. An alternative
would be to replace the older tanks with newer tanks which could
withstand the vacuum.
Based on the data available regarding current control technology
levels in the industry and the range of emission potential for these
tanks, EPA believes the 1993 proposed MACT requirements for these tanks
should be retained. However, industry has raised concerns that the
information submitted in the NCASI voluntary survey prior to proposal
is providing a misleading picture of current industry control
practices. The industry has also indicated that the emissions data from
the NCASI test program for these tanks is suspect. The industry is
collecting additional information on current operation, age, emissions,
and control practices for these tanks to supplement information already
provided to EPA.
EPA is considering whether distinguishing between types of weak
black liquor storage tanks is appropriate. Specifically, EPA is
considering the appropriateness of a distinction in age since newer
tanks may be structurally able to withstand a vacuum. EPA is
[[Page 9390]]
interested in any data on the age of the controlled tanks and the types
of controls in use. EPA is also interested in comments on whether age
is an appropriate parameter to consider for determining control
applicability.
Questions remain as to what level of control represents the MACT
floor for these different types of tanks. EPA will continue to discuss
these issues with industry and consider all available information to
resolve the MACT floor questions prior to promulgation.
Several commentors also stated that pre-washer knotter and
screening systems should not be controlled. Based on the data available
regarding current control technology levels in the industry and the
range of emission potential for these systems, EPA believes the control
of pre-washer knotter and screening systems represents a floor-level of
control. However, industry has raised concerns about the information
submitted in the NCASI voluntary survey prior to proposal because the
survey respondents were not clear as to their meaning when they
reported knotter systems as controlled, not controlled, or not vented.
The survey responses also did not indicate if the screening systems
were located before or after washing. Therefore, as with black liquor
tanks, questions remain concerning what level of control represents the
MACT floor for these equipment systems. Industry is collecting
additional information concerning the current operation, emissions,
equipment, and control levels in these systems to supplement the
information already provided. EPA is interested in any additional data
or information concerning the type of and control of emission points in
the knotter and screening systems, both pre and post-washer. EPA will
re-evaluate the MACT floor level of control for these sources prior to
promulgation.
At proposal, EPA characterized pulping wastewater and condensate
streams to be controlled as those with HAP concentrations above 500
ppmw. However, commentors said that the 500 ppmw level was an
inappropriate determinant for wastewater streams controlled at the MACT
floor and provided data to name each stream to be treated. Based on
review of these stream definitions and data submitted by the industry
to characterize these streams, EPA is inclined to agree that the 500
ppmv is inappropriate level and that naming the streams better
identifies the streams to be controlled at the MACT floor. EPA now
considers the subject wastewater streams to be foul condensates and is
inclined to adopt the following definitions of foul condensates and
ancillary equipment:
1. Foul condensates--any liquid streams originating from the
following process areas or equipment: batch digester relief and blow
gas system condensates; batch digester blow heat recovery system
condensates; continuous digester system flash steam condensates;
continuous digester chip steaming vessel condensates; turpentine
decanter underflow; non-condensible gas (NCG) system condensates; NCG
system low point drains; and condensates from the weak liquor feed
stage(s) in the evaporator system. Where vapors or gases from the
digester, turpentine recovery, NCG, and/or evaporator systems are
segregated into low-HAP and high-HAP concentration fractions through
multistage, differential, or selective condensation, only the high-HAP
fraction stream is considered foul condensate. If condensate
segregation is not performed on the process areas or equipment
identified above, the entire volume of condensate generated, produced,
or associated with the process area or equipment shall be considered
foul condensate.
2. Evaporator system--any and all equipment associated with
increasing the solids content of spent cooking liquor including, but
not limited to, pre-evaporators, evaporators (direct and indirect
contact), and concentrators.
3. Condensate segregation--the practice of generating, producing,
or isolating a high-HAP concentration-low flow rate condensate stream
from process vent vapors or gases in order to maximize the HAP mass and
minimize the condensate volume sent to subsequent treatment.
4. Segregated condensate stream (high-HAP fraction)--any condensate
stream that contains at least 65 percent by weight of the total HAP
mass (measured as methanol) that is present in the vapor stream prior
to condensation or isolation.
EPA is requesting comment on this named stream approach and on
whether the definitions shown above and on the pulping process
equipment systems discussed earlier, accurately represent the sources
of emissions to be controlled at the MACT floor and clearly define them
for purposes of compliance determinations.
EPA also re-evaluated control requirements for steam stripping--the
technology on which MACT for these wastewater streams is based. The
proposed standards required that the pulping wastewater streams subject
to control must meet one of the following: Recycle to a controlled
piece of process equipment, reduce the HAP concentration to below 500
ppmw, reduce total HAP or methanol by 90 percent, use the proposed
design steam stripper, or hardpipe the stream to biological treatment.
New performance data on all the currently operated steam strippers were
submitted after proposal (Pulp and Paper Water Docket item 20,027
attachment 3). The new data indicates that the best performing steam
strippers representing the floor level of control achieve a combination
of high percent methanol removal, high methanol mass removal, and low
outlet methanol concentration. Because methanol is a good indicator of
total HAP removal for pulping processes and associated wastewater, any
one of these parameters demonstrates that total HAP are being removed
from the condensate streams and therefore are not emitted to the
atmosphere. Based on that data, EPA now considers that mass removal and
outlet concentration are valid parameters to set control limits in
addition to percent removal as at proposal. The rule would allow mills
to: (1) Choose any wastewater treatment device as long as the device
achieves one of the three parameters and as long as the wastewater is
conveyed to the treatment device in an enclosed conveyance system; or
(2) recycle the wastewater streams to a piece of equipment meeting the
control requirements presented below.
EPA has evaluated the data in the NCASI condensate study (docket
item IV-J-32) and agrees with industry that bleached kraft mills
generate more HAP in pulping wastewaters than unbleached kraft mills
primarily because bleached kraft mills tend to digest the pulp longer.
While unbleached kraft mills can achieve the same percent methanol
removed as bleached kraft mills, unbleached kraft mills cannot attain
the same mass removed or outlet concentration as bleached mills.
Therefore, EPA currently intends to distinguish between bleached and
unbleached mills for the purpose of setting MACT level of control for
pulping wastewater.
The new industry data on steam stripping technologies indicates
that the MACT floor level of control for pulping wastewater at both
bleached and unbleached kraft mills is treating the foul condensate
wastewater streams to remove 92 percent of the HAP content (measured as
methanol). The data indicates that steam strippers achieving the 92
percent control also achieve an equivalent outlet concentration of less
than 330 and 210 ppmw measured as methanol, or remove 9.2 and 5.9
pounds of methanol/ADTP across the treatment
[[Page 9391]]
device, respectively for bleached and unbleached wastewater streams.
Mills would be allowed to use one of three equivalent limits to show
compliance.
EPA still intends to keep the provisions for recycling to enclosed
equipment and hardpiping foul condensates to a mill's biological
wastewater treatment plant. EPA is considering soluble BOD as a
compliance parameter alternative for biological treatment compliance
(docket items IV-D1-27, IV-D1-75, IV-D1-79, and IV-E-44). EPA is
interested in any comments concerning this compliance approach. EPA is
also re-considering the need for a design steam stripper.
New source MACT requirements have not changed since proposal. MACT
for new sources is based on the best level of control achieved from
similar sources. In other words, this technology was selected because
it is used by the best controlled similar source, as required by
section 112 (d) (3). The best controlled similar sources have the same
level of control as existing sources. In addition, the best controlled
source also controls deckers and post washer screen systems by not
venting or enclosing and routing vents to a control device.
B. Sulfite
The level of control for the sulfite industry in the December 17,
1993 proposal was the same as for all mill types (see previous
discussion on kraft mills). This section explains the level of the
standard under consideration for the projected sulfite subcategory. In
summary, EPA has reviewed what sources are being controlled, the
performance of the control technologies, and options for implementation
and setting emission standards for the sulfite industry.
EPA has reviewed public comments and industry data to evaluate the
emission sources controlled at the best performing mills for HAP
reductions. Pulping area sources controlled at the best performing
existing mills are the digesters, evaporators, and red stock washer
system vents (later referred to as the ``selected vents''). These
sources are the same vents as proposed except that knotters or deckers
which follow washers in the sulfite mills are now excluded from control
for existing sources because they are not part of the MACT floor.
Additionally, control of pulping wastewater with steam strippers has
been dropped from consideration since sulfite mills do not employ
stream strippers.
Many public comments stated that the control technology basis of
the standard for sulfite mills should not be combustion as proposed,
since very few mills combust emissions from the selected vents. The
data clearly indicate which emission sources are being collected and
vented to reduce or capture and recover SO2 emissions, which in
turn reduces HAP emissions by some degree. Sulfite mills use a
combination of the acid plant and separate scrubbing systems (e.g.,
nuisance scrubbers) to control and capture SO2 emissions. EPA and
industry have been meeting, collecting, and analyzing data to determine
the degree of HAP emission reduction achieved in these control devices
or systems designed to collect SO2 emissions. Recently, NCASI
provided a summary of the available industry emissions data and
American Forest and Paper Association (AF&PA) made recommendations to
EPA on the MACT standards for sulfite mills (docket items IV-D1-87, IV-
D1-88, and IV-D1-94). In summary, AF&PA recommended that certain named
air emission sources be vented to existing SO2 recovery systems
and that ammonium- and magnesium-based sulfite mills could not recycle
condensates with annual average methanol concentrations exceeding 500
ppmw to pulping and chemical recovery equipment unless the equipment
was being vented to an SO2 recovery device or unless the total
emissions from the all pulping and chemical recovery equipment do not
exceed 2.5 pounds methanol per ton of oven-dried pulp (lb/ODTP).
EPA has used the concept of naming both the sources to be
controlled and the control device on all the other pulping
subcategories. However, for those other subcategories, the named
controls are well understood and emission reduction performance was
well documented. Named control devices for the other subcategories were
specified to meet either a known percent reduction standard, equipment
design standard (e.g., 98 percent control or operate at 1600 degrees
Fahrenheit and 0.75 second residence time for incinerators), or the
named control device is known to operate in a manner to destroy the
emissions to a certain level (i.e., venting to lime kilns or recovery
boilers reduces emissions by at least 98 percent due to very high
operating temperatures). However, for SO2 recovery devices or
systems at sulfite mills there are many combinations of systems used
with various desired SO2 capture efficiencies. Some of these
systems have been shown to be better than others in reducing HAP
emissions. Therefore, simply naming existing SO2 control systems
as the HAP control device does not set a known HAP level of performance
for sulfite mills. EPA must evaluate and set the HAP emission limits
achieved by the best performing existing sources (in this case, the
best performing five mills since there are less than 30 sources
(section 112(d)(3))).
For this evaluation, EPA considered various types of performance
measurement standards for the sulfite industry. Options include
equipment and work practice standards, percent reduction standards,
and/or emission limit (concentration or mass) standards for each or a
combination of streams. As discussed earlier an equipment and work
practice standard is not appropriate. Also, EPA considers that using a
standard that combines emission streams instead of setting individual
stream limits provides the best fit, least expensive, and most flexible
standard since existing mills already use various combinations of
SO2 control technologies for different and varying types of
emission streams. Thus, a mill could use any combination of controls
plus add-on controls or process changes that best fit the existing
facility to get the same emission reduction. EPA evaluated percent
reduction and emission limit standards and found that limits could be
set, based on the best available information. The discussion on how
those limits were determined is found later in this section.
Based on EPA's review of the quantity and quality of data and the
variability in the industry, EPA does not intend to set these limits as
continuous emission limits. Rather, EPA intends that several initial
performance tests be performed using the average of three one-hour
tests when the mill is operating under normal operating conditions to
determine if the control system meets the emission standard. During the
performance test, process and control equipment parameters will be
required to be monitored and matched with the emission limits to
determine the operating and monitoring conditions to be monitored for
long-term compliance with the standard. EPA has used this approach on
other standards to provide flexibility in process operation while
assuring compliance.
Under this program, the owner or operator of the source will
recommend and demonstrate to the permitting authority the appropriate
equipment parameters to be monitored, and the allowable range for those
parameters to demonstrate compliance with the emission standard. This
recommendation would include the data collected during the performance
test supplemented by engineering
[[Page 9392]]
assessments and equipment manufacturer's recommendations. The source
would not be out of compliance with the standard when the source
operates outside those operating conditions if the source reports
(prior to any EPA compliance or enforcement action) and documents that
the episode is during a start-up, shut down, or malfunction as defined
in section 63.2 of the General Provisions. And, the source must
demonstrate that conditions have changed and a retest of the initial
performance test shows compliance with the emission standard.
EPA is considering establishing two emission limit strategies to
demonstrate compliance: mass balance and percent reduction of the
selected vents. Since only methanol data was available for determining
either standard, methanol would be used in this case as a surrogate for
total or individual HAP emission standards. From the recent NCASI
summary of sulfite data, it is clear that calcium-based sulfite mills
have lower emissions because they do not have the extensive recovery
system that ammonium and magnesium-based mills require. Therefore,
emission standards for calcium-based mills will be considered
separately from ammonium and magnesium-based mills.
Section 112 of the Act requires EPA to establish limits based on at
least the average of the five best controlled mills when there are less
than 30 mills. The data set available to EPA to set a mass limit and
percent reduction limit is limited; however the available data
indicates that the average of the three existing calcium-based mills
emit a total of 0.02 lb methanol/ODTP from vents where the selected
sulfite vent emissions are collected and processed. The data set
indicates that the average emissions from the top five ammonium-based
and magnesium-based mills are a total of 0.45 lb methanol/ODTP from the
vents where the selected sulfite vents are collected and processed.
Additionally, the total of the selected vent emissions does not account
for the total air emissions from these systems since scrubbers are used
in the SO2 recovery systems. The scrubbers transfer some of the
HAP from the vents to wastewater that is subsequently sewered. Air
emissions from the sewered recovery system wastewater occur in the
mill's open wastewater collection and processing equipment due to
volatilization. These air emissions from wastewater can be calculated
using EPA's WATER8 Emission Model available on the TTN (under Chief
BBS, Emission Estimation Software, file: water8.zip).
EPA reviewed all the sulfite wastewater data available and the
amount volatilized from an average wastewater system (calculated to be
6 percent lost for methanol using WATER8) and estimates that an average
sulfite mill emits 0.63 lb methanol/ODTP. Estimates from industry
provided earlier in the year also indicated similar results. Industry
has agreed to provide details on sulfite mill wastewater collection and
treatment systems to better estimate the emissions from those systems
since wastewater emissions may be a significant portion of the total
HAP mass emission rate. The total average mass emissions from the
selected sulfite mill vent control systems at the best performing mills
(including vents and wastewater air emissions) are estimated to be 0.65
and 1.10 lb methanol/ODTP for calcium-based and ammonium and magnesium-
based mills, respectively. Using the appropriate value, a mill could
then achieve the emissions reduction under this total mass emission
standard across the selected vents, and the connected recovery system
vent and wastewater emissions.
As noted earlier, industry recommended a much higher vent mass
emission limit of 2.5 lb methanol/ODTP in the industry's sulfite mill
recommendation on limits for recycling wastewater. Industry
representatives stated that the 2.5 lb methanol/ODTP estimate was
derived from the same data set and they derived a similar estimate as
the 0.45 lb methanol/ODTP value discussed above. However, the industry
representatives increased the value (from 0.45 to 2.5) to take into
account variability of testing procedures, mill operating conditions,
and the types of products produced. Industry is currently documenting
their variability calculations and rationale and providing it to EPA
and the rulemaking docket. EPA currently believes that the approach
discussed earlier for implementing these emission limits will
adequately account for variability. However, EPA will consider the
industry rationale and data.
EPA does not have data to support or deny the industry's 500 ppmw
recommendation. Industry is recommending condensate streams exceeding
500 ppmw of methanol should not be allowed to be used/recycled in the
pulping or chemical recovery area to process equipment vented directly
to the atmosphere unless it meets 2.5 lb methanol/ODTP. EPA requests
data and comments on this approach.
The second emission limit approach under consideration for sulfite
mills is setting a mass reduction of HAP emissions from the applicable
emission points. Industry tested two SO2 nuisance scrubbers and
found that while one reduced vent emissions of methanol by 95 percent
and emissions of total HAP by 94 percent, the other SO2 scrubber
increased HAP emissions. Since nuisance scrubbers are only one part of
the recovery system for most mills, the scrubber efficiency alone does
not represent what the total system is controlling. A second approach
was developed that used the mass emission limit derived above and data
on the amount of methanol generated. An industry engineering estimate
indicates that between 15 and 20 lb methanol/ODTP generated in the
sulfite process. Of the amount generated, as much as 8 lbs methanol/
ODTP may be emitted from the selected vents as shown in the recent
NCASI summary of sulfite data. Comparing this amount to the mass
emission rates (0.65 and 1.1 lbs methanol/ODTP) discussed above at the
best performing mills, 92 and 87 percent of the methanol is removed
across the total selected sulfite mill vent control system for calcium-
based and ammonium and magnesium-based mills, respectively. In
conclusion, mills would have to meet either the mass emission or the
mass percent reduction standard across their control system to be in
compliance.
Industry has indicated concern over the numerical mass limits and
percent reductions discussed in this notice because they are based on a
limited data set and because HAP reductions resulting from control
devices installed originally for SO2 control is not well
understood. EPA will review and consider additional data being
collected by this industry and other public commentors to set a HAP
level of performance for sulfite mills prior to promulgation and will
adjust these numerical values as necessary. EPA solicits comments on
the two emission limit strategies for sulfite mills discussed above and
solicits comments on the appropriate numerical values for these
strategies.
New source MACT is based on the best level of control achieved at
baseline. The data shows the best controlled sulfite mills control the
same emission sources as the requirements for existing sources and also
control weak or spent liquor tanks, strong liquor storage tanks, and
acid condensate storage tanks. The best sulfite mills also have non-
venting knotter and screening systems. Therefore, new source MACT is
the same as existing source MACT, as well as, the control of the
aforementioned storage tanks and the
[[Page 9393]]
installation of non-venting knotter and screening systems. EPA
currently plans to require new sources to meet the same mass emission
limit or percent reduction as discussed for existing sources.
C. Semi-chemical
The proposed standards did not differentiate between pulping types;
therefore, the owners or operators of new or existing semi-chemical
mill sources were required to comply with the same standards as kraft
pulping. EPA is considering changing the MACT requirements for semi-
chemical mills to be the control of LVHC vents only (as defined in
section VI.A). Data show that the MACT floor level of control at semi-
chemical mills is collecting LVHC vent emissions and reducing emissions
to the same level as previously proposed in 1993 and discussed earlier
in this notice for kraft mills.
EPA considered whether it would be appropriate to go beyond the
MACT floor at semi-chemical mills to control some of the additional
larger emitting process systems, such as pulp washer systems, that
would be controlled at kraft mills. However, data indicates that
emissions from semi-chemical mills are generally much less than at
kraft mills. Therefore, considering the smaller emission reduction and
the costs to control units beyond the floor, EPA is inclined to set
MACT for semi-chemical mills at the floor (controlling LVHC vent
emissions).
In evaluating the information and through discussions with
representatives from semi-chemical mills, EPA is aware that the best
controlled mills collecting and controlling LVHC vents tend to be
collocated with kraft mills. EPA considered whether a distinction
between collocated and stand-alone semi-chemical mills should be made
for the purpose of setting MACT requirements. EPA determined that there
is no difference in the nature of the vents being collected, and the
level of control is technically feasible and can be achieved at a
reasonable cost; therefore, there is no need to distinguish between
these types of mills. EPA estimates that the control of the LVHC vents
at a typical semi-chemical mill will reduce emissions by 160 Mg of HAP
per year and 1,700 Mg of VOC per year; the cost-effectiveness for a
typical stand-alone semi-chemical mill will range from $1,000 to
$3,000/Mg of HAP. Industry cost estimates fall within that range
(docket item IV-D1-62, IV-D1-86, IV-D1-89, IV-D1-90, and IV-D1-92).
Semi-chemical mill representatives also believe the control of LVHC
vents is a reasonable level of control for stand-alone mills as well
(docket item IV-D1-72 and IV-E-68). Therefore, EPA now considers the
control of the LVHC vents at both types of mills to be MACT and a
distinction is not warranted.
The MACT level of control for HAP emissions from semi-chemical mill
wastewater is no control. EPA is not aware of any semi-chemical mills
treating process wastewaters with steam strippers as is found in the
kraft industry. Since semi-chemical mills generate less HAP than the
kraft process, and therefore, lower HAP-containing streams, EPA does
not consider going beyond the floor to control semi-chemical wastewater
streams to be appropriate.
New source MACT is based on the best level of control at similar
sources. Data indicate the best controlled semi-chemical mills combust
the same LVHC emissions plus the pulp washing system emissions. EPA
anticipates the trend in industry will be to install washer systems
with lower flow rates. This in turn allows for less expensive control
systems. The costs are also reduced at new sources since the controls
can be considered and planned into new equipment installation as
opposed to retrofitted.
Therefore, new source MACT would be the same as existing source
MACT plus the control of the pulp washing systems. EPA has not had a
recent opportunity to discuss this contemplated new source control
level with the affected mills and public and solicits comments and data
on the appropriate levels of control for new sources at these mills.
D. Soda
As discussed previously in section V, subcategorization, EPA
currently plans to establish separate MACT standards for soda mills.
Based on information and data obtained since proposal, EPA now
considers the control of LVHC vents (as defined in section VI. A) at
these mills to be MACT.
Data available to EPA indicate that soda mills do not currently
control any of the equipment that is subject to the MACT requirements
for kraft mills. However, EPA has determined that the emissions from
soda mills are similar to kraft mills and the control costs are similar
to stand-alone semi-chemical mills. Therefore, EPA considers going
beyond the floor to control LVHC vent emissions at soda mills to be an
appropriate level of control for MACT for these mills, taking into
consideration the costs of achieving the controls as well as the other
factors enumerated in section 112(d)(2). EPA estimates that control of
the soda mill LVHC system vents, at a typical mill, will reduce
emissions by 130 Mg of HAP per year and 1,500 Mg of VOC per year.
Data show that no soda mills currently practice steam stripping to
control HAP's in wastewater. EPA initially does not believe the costs
of control of these streams to be warranted, within the meaning of
section 112(d)(2). Therefore, the MACT for the control of HAP in
wastewater would be no control.
The new source requirements are based on the best level of control
at similar sources. Data show that no soda mills are currently
practicing any level of HAP control. However, the control of washing
systems is demonstrated at similar sources (i.e., semi-chemical and
kraft washing systems). Therefore, as discussed in section VI.C for
semi-chemical mills, EPA now considers the control of washing systems
for new sources to be part of MACT. Therefore, new source MACT for soda
mills would be the same as new source MACT for semi-chemical mills
(LVHC and washing system controls). EPA has not had a recent
opportunity to discuss these contemplated new and existing source
control levels with the affected mills and public, and solicits
comments and data on the appropriate levels of control at these mills.
E. Bleaching
EPA is considering changing the proposed MACT requirements for
bleach plants. EPA is also considering making a distinction between
requirements for papergrade versus dissolving grade mills. Changes to
the proposed MACT standard would include only requiring controls for
chlorinated HAP's. The control requirements to achieve chloroform
reductions would be based on a combination of compliance with the
future BAT requirements imposed under the Clean Water Act (only for
papergrade bleach mills) and the enclosure of all bleaching equipment
and routing the vents to a scrubber for all bleach stages where
chlorinated bleaching agents are introduced to control the other
chlorinated HAP's (at all bleach mills). As at proposal, a mill would
be allowed to use chlorine as a surrogate for compliance with these
other chlorinated HAP's around the scrubber. Control of non-chlorinated
HAP's (with methanol as a surrogate), as required at proposal, would be
dropped because data indicate that the best controlled mills do not, in
fact, achieve control of these pollutants. The rationale for these
changes under consideration is set forth below.
[[Page 9394]]
The proposed standards require owners or operators of new or
existing sources to enclose and vent all bleaching component emission
points into a closed vent system routed to a control device. The
proposed MACT was based on caustic scrubbing as the control device.
Vents or enclosed process equipment with volumetric flow rates or total
HAP concentration below certain specified limits were not subject to
control. EPA requested comment on whether MACT should also include
process changes and if a separate MACT standard for chloroform is
appropriate. Based on data received, EPA now considers the chlorinated
HAP limit to be based on the emissions reduction achieved using a
combination of scrubbing and process modifications. Therefore, EPA is
considering setting a MACT standard for both chloroform and other
chlorinated HAP's (chlorine as a surrogate).
Industry provided data for existing bleach plant emission estimates
and scrubber efficiencies. The data clearly indicates that mills
practice significant control of chlorine and chlorine dioxide through
the use of caustic scrubbing (docket item II-I-24). However, existing
bleach plant scrubbers are operated with high recirculation rates which
result in no removal for methanol and other organic HAP compounds
(docket item IV-D1-34). The data also shows reduced chloroform and
other chlorinated HAP emissions with process changes (docket item II-I-
10); however, the data indicate that there are no significant increases
in non-chlorinated HAP emissions. Therefore, EPA currently plans to
drop the total HAP percent reduction limit for methanol and other
nonclorinated organic HAP's.
As discussed earlier, EPA is evaluating two types of bleaching
processes; the distinction is necessary for the purpose of setting
standards for chloroform. These two types of processes are papergrade
bleaching and dissolving grade bleaching, to be defined the effluent
guidelines portion of the cluster rule. The average emission limitation
of the best controlled papergrade bleaching processes result from
control of chloroform and the other chlorinated HAP emissions through a
combination of caustic scrubbing, high levels of chorine dioxide
substitution, and eliminating the use of hypochlorite. The average
emission limitation of the best controlled dissolving grade bleaching
processes also control emissions of the other chlorinated HAP through
caustic scrubbing but tend to use hypochlorite and lower levels of
chlorine dioxide substitution. Therefore at this time, EPA has been
unable to identify the appropriate process modifications for which to
base the chloroform emission control level.
EPA's Office of Water (OW) is currently planning to revise its
technology basis for limits based on results of ongoing studies by
dissolving mills of alternative process technologies different from
those which served as the proposed effluent guidelines. Significant
objectives of these studies include the extent to which hypochlorite
use can be reduced and chlorine dioxide substitution increased in order
to reduce generation and release of chlorinated organic pollutants,
such as chloroform, while maintaining dissolving pulp properties
acceptable to end users of these pulps. When data for these studies
become available, EPA will revise its proposed effluent limitations and
BAT technology option as appropriate, and evaluate data to set
chloroform MACT standards for dissolving grade mills. EPA is interested
in any data concerning chloroform emissions from dissolving grade
bleaching processes and requests comment on an appropriate chloroform
MACT for new or existing dissolving-grade bleach plants.
As proposed, emissions of the other chlorinated HAP (or chlorine as
a surrogate) are to be reduced by 99 percent. EPA is considering also
allowing mills to meet an outlet concentration below 10 parts per
million by volume (ppmv) of HAP from the scrubber exhaust as an
alternative to the 99 percent reduction standard. Commentors asked for
an alternative level to the 99 percent reduction standard because high
substitution rates reduce the bleach vent emissions to the extent that
99 percent reduction across the scrubber is not attainable. Based on
the review of data, the 10 ppmv standard is considered equivalent to
the outlet of scrubbers achieving 99 percent removal (docket item II-I-
24). EPA also is considering whether a mass limit on the scrubber
exhaust would be an appropriate equivalent alternative, and solicits
comment and data on the need and appropriate level for a mass limit.
For papergrade bleaching processes, compliance with OW's BAT option
for papergrade bleaching (anticipated to be based on at least 100
percent chlorine dioxide substitution and no hypochlorite use) is at
least as stringent as the MACT floor (high chlorine dioxide
substitution). Therefore, EPA plans to specify papergrade BAT as
compliance for chloroform at paper grade bleach plants. EPA requests
comments on whether an alternative equivalent numerical limit for
chloroform is needed for papergrade bleaching processes.
EPA's intent for bleaching wastewater is unchanged from proposal
(i.e., no control). New source MACT for bleach plants would be the same
as existing source MACT for both papergrade and dissolving grade bleach
plants. The installation and operation of the totally chlorine free
(TCF) bleaching process meets all the bleaching process MACT standards
for papergrade bleaching and would constitute compliance.
VII. Compliance Extension for Kraft Mills
EPA is committed to the goals of the cluster rule, and believes
that the cluster rule will ultimately result in lower overall
compliance costs, while still providing environmental and human health
protection. However, EPA recognizes the unique compliance and timing
issues that the cluster rule may create. EPA has identified one
situation that may warrant additional compliance time to fully realize
the goals of this rule. EPA is inclined to agree with industry
representatives who have stated that additional time is warranted for
brownstock washers and oxygen delignification units at kraft mills. EPA
believes the additional time would ensure that the maximum degree of
overall multi-media pollution reduction is achieved, without requiring
unnecessary compliance costs.
Many kraft mills are currently considering the addition of oxygen
delignification (OD) to their pulping process lines by the year 2000.
The addition of OD has been shown to have significant environmental
benefit. An OD unit reduces the need for chlorinated chemical
application in the bleaching process, which results in reduced loadings
of chlorinated pollutants to the air and into the bleach plant
effluent. Less water is required in the bleaching process which, in
turn, brings a mill closer to the ``closed mill'' design, with zero
water discharge. EPA is strongly committed to pollution prevention
efforts such as these. There is also a cost savings for the industry by
using OD in the form of reduced chemical usage and less net energy
usage.
To gain the maximum benefit from adding OD units, the brownstock
washers typically need to be redesigned to improve pulp washing. The
trend in the industry is toward newer washing technologies that are
more efficient, require smaller space in the mill, are less polluting
and easier to control. EPA encourages the use of these pollution
prevention technologies, but recognizes the evaluation and
implementation of
[[Page 9395]]
these technologies would add time and expense to the compliance
activities for these sources.
EPA is particularly concerned that if mills had to control vents on
brownstock washers within the 3-year compliance period, time
constraints would dictate that they retrofit their current washers with
a vent gas collection system. Once such a collection system is
installed, mills would likely postpone installation of OD or choose not
to install it at all; as discussed earlier, installation of OD
generally requires brownstock washer upgrades. The upgraded washers
plus the new OD system would require a differently designed gas
collection system. Once mills commit capital to retrofit their current
equipment, they would be very unlikely to entertain technologies such
as OD that would require tearing out and rebuilding or replacing the
gas collection system within a few years. (In such a case, there is a
serious question whether imposition of a standard that results in
foregoing substantial cross-media environmental benefits could be MACT.
Portland Cement Association v. Ruckelshaus, 486 F.2d 375, 385-86 at
n.42 (DC Cir. 1973); Essex Chemical Corp. v Ruckelshaus, 486 F.2d 427,
439 (DC Cir. 1973), EPA must consider non-air environmental impacts in
determining what constitutes a ``best'' technology.)
EPA considers the installation of improved washers and OD to be an
important step toward totally chlorine free bleaching. Total chlorine
free bleaching, while still evolving, provides significant benefits
such as elimination of chlorinated pollutants to the environment and
allows bleach plant effluents to be recycled to the mill. These
benefits result in a large reduction in mill water intake and moves a
mill further toward the closed mill concept.
This additional design and mill modification can be a lengthy
process. EPA wants to allow sufficient time for each mill to fully
consider all pollution control options. EPA also recognizes that the
pulp and paper industry will be implementing both water and air rules
essentially at the same time; many of the changes a mill will need to
implement to comply with the water requirements must be considered
before control of air emissions from the washer and OD systems can be
enacted. Given the engineering requirements, capital expenditures,
permitting requirements, and the time necessary to implement the water
standards, EPA questions whether it is even possible to install
controls for air emissions from OD and washers currently in place
within 3 years.
Much of the discussion in this section is centered around OD. It
must be pointed out that while OD may not be included in the control
basis for BAT at kraft mills, EPA is considering taking a number of
steps, this compliance extension being one, to encourage mills to adopt
the technology. EPA's Office of Water, in a separate Federal Register
notice to follow shortly, will address the process technologies that
are likely to be considered as the underlying basis for BAT effluent
limitations. EPA also will present a plan for incentives being
considered for mills that have installed or will install technologies
that achieve more stringent removal of pollutants from wastewater than
is likely to be required based on BAT.
EPA is thus considering providing an additional 5 years beyond the
3-year compliance time for the remaining units for a total compliance
time of 8 years from the date of promulgation. EPA believes this would
allow sufficient time for a complete evaluation of all pollution
control options. Some limited information on the status of their
compliance activities for these sources would likely be required in
their annual compliance report.
EPA is, of course, aware that section 112 (i) (3) (A) states that
compliance with a MACT standard shall be no later than 3 years from the
standard's effective date. EPA notes, however, that there are special
circumstances present in this instance. First, as described above, a
three year compliance period raises the likelihood of mills which might
otherwise choose to install OD foregoing water quality and pollution
prevention benefits if they are forced to retain their existing
brownstock washing system in order to justify the capital cost of vent
controls on that system. Second, as a legal matter, EPA could develop a
rule with the same contemplated compliance date (i.e. of 2004) by
simply rescheduling this part of the pulp and paper air rule into the
so-called 10-year bin under section 112 (e) (1) (E), and rescheduling a
10-year rule. (Section 112 (c) (1) contemplates revisions in EPA's
initial schedule, and EPA has been held to have continuing discretion
to reschedule under a similar scheduling scheme in the Resource
Conservation and Recovery Act. Chemical Waste Management v. EPA, 869 F.
2d 1526 at n. 2 (D.C. Cir. 1989).) Because of the benefits of the
cluster rulemaking process, which allows EPA to develop and affected
companies and members of the public to gauge the multi-media effect of
contemplated rules at one time, EPA prefers to promulgate the standards
at the same (or close to the same) time. EPA does not believe the
cluster process needs to be abandoned to provide a compliance date it
could achieve by other means.
Much of the rationale for the compliance extension is to encourage
kraft mills to install superior water pollution-control technology, yet
the extended compliance time line contemplated in this notice would be
available to all kraft mills, whether or not they choose to adopt that
superior technology. EPA solicits comments on whether such a compliance
extension should only be available to mills that commit to install
technologies that achieve more stringent removal of pollutants from
wastewater than is likely to be required based on BAT.
VIII. Emissions Averaging
The proposed regulations did not contain provisions for emissions
averaging; however EPA requested comments on the subject. EPA is
interested in emissions averaging because it is equally protective,
adds flexibility, and can also reduce the costs of compliance and
testing. At proposal, EPA did not include an emissions averaging
approach because of data limitations and concerns over how to implement
an averaging approach due to concerns about process variability.
Several commentors indicated support for emissions averaging on the
basis of providing compliance flexibility for the industry, but stated
that an individual approach to emissions averaging, such as
contemplated at proposal, would be too burdensome and inappropriate for
this industry. Conversely, some commentors indicated that emissions
averaging would be difficult to enforce.
After proposal, the industry submitted a concept for compliance
with the proposed NESHAP regulations that is an alternative type of
emissions averaging that is unique and potentially more appropriate for
this industry. While the proposed NESHAP regulations focus primarily on
combustion of specific process vents, the industry provided preliminary
information detailing an alternative compliance plan designed to reduce
the amount of HAP's present in pulping condensate streams that are
recycled to other process areas in the mill (docket item IV-D1-95).
Recent industry data has indicated that a significant portion of
emissions from process areas such as brownstock washing and
causticizing area could be attributed to volatilization of compounds
present in the recycled condensates. Reducing the pollutant
concentration in the recycled condensates would, in turn, lower the
amount of pollutants volatilized from process areas that receive
recycled
[[Page 9396]]
condensates and reduce emissions from bleach plants and paper machines
associated with HAP carry over from pulp washing processes.
The industry's compliance alternative, referred to as the ``Clean
Water Alternative,'' consists of routing pulping area condensates to a
biological reactor to remove the HAP's. The effluent from the reactor
could then be used in other process areas in the mill (e.g., brownstock
washing, causticizing area, etc.). The emission reduction achieved by
the alternative would be associated with using condensates with lowered
HAP concentrations throughout the mill.
The industry believes that significantly reducing the HAP
concentration in recycle process waters using the biological reactor
would achieve greater HAP emissions reduction across the whole source
than the proposed NESHAP. EPA is currently evaluating whether the
industry's clean water alternative would achieve or exceed the HAP
emissions reduction achievable using the control techniques on which
the proposed regulations are based. In addition, EPA will be evaluating
secondary impacts associated with using the clean water alternative.
Conceptually, the industry's proposal would reduce emissions from
process units that receive recycled condensates. Biodegradation of HAP
compounds has been widely documented; however, this approach to
emissions reduction has not been demonstrated in the pulp and paper
industry.
While the industry's clean water alternative is innovative,
additional information must be provided in order to make this proposal
a viable compliance option. Industry supplied additional data to
improve the emission factors (docket item IV-D1-59), but the data was
not sufficient to address EPA's concerns about process variability. The
types of information EPA is interested in obtaining to address these
concerns are: (1) Detailed information, such as: emission calculations;
assumptions used; references; typical process/condensate flow diagrams
(if needed); data supporting relationship between stream concentration
and air emissions; any other data/information necessary to support an
independent evaluation of the industry's claims of performance; (2)
strategies for demonstrating compliance with the NESHAP regulations,
such as the specific reactor performance parameters to be monitored
(e.g., inlet and outlet HAP concentration, hot water tank outlet HAP
concentration, temperature of recycled water; identification of process
equipment receiving treated condensates); and (3) methods for enforcing
compliance with the NESHAP regulations using the industry's
alternative, such as sufficient recordkeeping and reporting
requirements associated with reactor operation.
IX. Relationship to Other Rules
A. New Source Review/Prevention of Significant Deterioration
Applicability
To comply with the MACT portion of the pulp and paper cluster rule
under development, mills will route vent gases from specified pulping
emission points to a combustion control device for destruction. Mills
may use steam strippers to reduce emissions from pulping wastewater.
The incineration of sulfur-laden gases from pulping vents and/or steam
stripper overheads has the potential to generate sulfur dioxide
(SO2). To a lesser degree, the use of supplemental fuels to
support vent gas combustion and the generation of additional steam for
steam strippers may increase emissions of SO2, nitrogen oxides,
particulate matter (PM and PM10), and carbon monoxide.1 For
these reasons, commentors have indicated that compliance with the
proposed cluster rule could trigger major NSR or PSD review.
\1\ Commentors raised similar concerns with respect to the
technologies that would be installed to meet the proposed effluent
limitations in the cluster rule. These issues will be addressed in
the forthcoming water notice.
---------------------------------------------------------------------------
Industry and some States have commented extensively on the
potential problems resulting from the interaction of the cluster rule
under development and NSR. They have indicated that in developing the
rule, EPA did not take into account the impacts that would be incurred
in triggering NSR. Commentors indicated that PSD or NSR review
processes would: (1) Cost the pulp and paper industry significantly
more for permitting and implementation of NSR and PSD requirements than
predicted by EPA; (2) impose a large permitting review burden on State
air quality offices; and (3) present difficulties for mills to meet the
proposed NESHAP compliance schedule of three years due to the time
required to obtain a pre-construction permit. Commentors indicated that
compliance with the proposed rule would make permitting extremely
complex, pointing out that in some cases, sources would be required by
one set of regulations to install emissions controls and constrained
from beginning construction on those controls in the absence of a
permit by another set of regulations. The commentors also suggested
that EPA provide an exemption from major source NSR and PSD review,
preferably using the pollution control project exclusion.2
\2\ A similar issue was resolved in the 1992 WEPCO rulemaking,
where EPA amended its PSD and nonattainment NSR regulations as they
pertain to electric utilities, by adding certain pollution control
projects to the list of activities excluded from the definition of
physical or operational changes, subject to certain safeguards.
Pollution control projects were defined as ``any activity or project
undertaken [at an existing electric utility steam generating unit]
for purposes of reducing emissions from such a unit.''
In a July 1, 1994 guidance memorandum issued by EPA (available
on the TTN Bulletin Board), EPA extended a limited pollution control
project exclusion for source categories other than electric
utilities. The guidance indicated that unless information regarding
a specific case indicates otherwise, add-on controls and fuel
switches to less polluting fuels can be presumed, by their nature,
to be environmentally beneficial.
---------------------------------------------------------------------------
Based on evaluation of pollutant reductions, environmental, and
energy impacts, EPA considers projects implemented to comply with the
MACT portion of the cluster rule to be environmentally beneficial. EPA
therefore considers these projects to be pollution control projects
under current policy guidance issued in an EPA memorandum dated July 1,
1994. As discussed in the guidance, the exclusion does not affect any
minor NSR permitting requirements in a State implementation plan, which
also facilitates the safeguards outlined in the policy guidance.
Further, EPA expects that projects undertaken to meet the MACT portion
of the cluster rule will also qualify as PCP's under forthcoming NSR
reform regulations.
EPA solicits public comment on its determination that control
device projects installed to comply with the MACT portion of the
cluster rule are environmentally beneficial and eligible for exemption
from major NSR as PCP's under current policy guidance. EPA also
solicits public comments on providing a specific exclusion in the major
NSR rules for these types of controls installed to comply with the MACT
portion of the cluster rule.
B. Boiler/Industrial Furnace/Resource Conservation and Recovery Act
Applicability
The proposed pulp and paper NESHAP requires the use of steam
stripping to remove HAP's, primarily methanol, from wastewater. After
removal, the NESHAP would require the HAP-laden vent gases from the
steam stripper to be sent to a combustion device for destruction.
Several commentors indicated that sending the steam stripper overheads
to a combustion device was not the most efficient and cost effective
way to destroy vent gases due to the high
[[Page 9397]]
moisture content and variable heat value of these vent gases. The
commentors recommended sending the stripper vent gases to a
rectification column followed by condensation to obtain a concentrated
condensate (primarily methanol). The concentrated condensate could then
be burned in an on-site combustion device as fuel.
This approach to condense and burn the concentrated condensate
takes advantage of the condensate's energy value and should assure
substantial destruction of HAP's due to the MACT standard. However, as
explained below, under current rules, condensing the steam stripper
vent gases could result in RCRA regulation of the condensate, including
regulation of the combustion unit.
As proposed, the combustion of steam stripper vent gas does not
trigger the BIF regulations because the methanol-laden vent gas is not
a RCRA hazardous waste--it is not listed as a hazardous waste, nor does
it exhibit a hazardous waste characteristic. However, if the methanol
from the steam stripper overheads is condensed before burning, the
flash point of the liquid drops to below 140 degrees Fahrenheit, and
the liquid may therefore be identified as hazardous waste because it
exhibits the ignitability characteristic (set out in 40 CFR
Sec. 261.21). To avoid the imposition of RCRA BIF regulations,
commentors recommended incorporating a ``clean fuels'' exemption into
the pulp and paper NESHAP so that the condensate can be burned for
energy recovery without the combustion unit also being subject to the
RCRA rules.
The ``clean fuels'' exemption is a recommendation from EPA's Solid
Waste Task Force (SWTF) to allow recovery of energy from ``clean''
waste-derived fuels such as ethanol, methanol, and hexane. The
recommendation is contained in ``Re-engineering RCRA for Recycling''
(EPA 530-R-94-016, November 1994). The ``clean fuels'' exemption was
developed by the SWTF to promote burning for energy recovery hazardous
waste fuels that are considered hazardous only because they exhibit the
ignitability characteristic (i.e., have a flash point below 140 degrees
Fahrenheit).
The industry submitted information detailing the composition of
condensates derived from steam stripper overhead gases (docket items
IV-D1-51 and IV-D1-56). However, the determination if the condensates
meet the requirements for the clean fuels exemption has not yet been
conducted by EPA's Office of Solid Waste. Indeed, the soon-to-be
proposed standard for hazardous waste combustion units proposes
exclusions based on a comparable fuel test (rather than a risk-based
test of how ``clean'' the fuel is) involving a comparison with fossil
fuels.
EPA does not believe as an initial matter that RCRA regulation of
combustion of the condensate is needed. Although the clean fuel and
comparable fuel approaches are too nascent for immediate national
application, it still appears that this condensate could be combusted
pursuant to the MACT standard without presenting risks warranting
immediate RCRA control. The condensate does not appear to contain metal
or chlorinated organic HAP's; a volatile HAP (methyl ethyl ketone at
1638 milligrams per liter (mg/l)) and a volatile compound (acetone at
2364 mg/l) were the maximum concentrations detected, and they would be
substantially destroyed under the MACT standard. In addition, EPA
believes that allowing the burning of this condensate does not produce
any additional HAP's due to the high temperatures and residence times
found in pulp and paper combustion devices that would be used to comply
with the proposed MACT standard. Moreover, burning condensate will not
increase the potential environmental risk over the burning of the steam
stripper vent gases prior to condensation. Additionally, the use of the
condensate as a fuel could reduce or eliminate the need for
supplemental firing of fossil fuels in such combustion devices, thereby
decreasing the emission of criteria pollutants (NOX, PM, SO2,
CO). Consequently, EPA believes that regulation under RCRA is not
necessary since the practice would not increase environmental risk,
reduces secondary impacts, and would provide a cost savings. Further
considerations of risk can appropriately be handled as part of the
section 112(f) residual risk determination. For these reasons, EPA is
proposing to exempt specific sources at kraft mills that burn
condensates derived from steam stripper overheads from the BIF
requirements of RCRA.
This decision is consistent with RCRA section 1006, which requires
EPA to ``integrate all provisions of [RCRA] for purposes of
administration and enforcement and * * * avoid duplication, to the
extent practicable, with the appropriate provisions of the Clean Air
Act * * *.'' EPA believes that the imposition of RCRA regulations in
this instance could result in the types of unnecessary duplication that
section 1006 is intended to prevent. EPA now considers that steam
stripping with rectification followed by combustion of the concentrated
condensate is MACT considering energy, economics, and air environmental
impacts. Additional regulation under RCRA is redundant and not likely
to result in any additional emission or risk reduction. Any further
concerns on this issue would more properly be addressed through the
section 112(f) residual risk process which requires EPA to assess the
risk to public health remaining after implementation of the NESHAP
under section 112(d). See generally 60 FR 32587, 32593 (June 23, 1995),
and 59 FR 29570, 29776 (June 9, 1994) where EPA similarly found that
RCRA regulation of secondary lead smelter emissions was unnecessary, at
least until completion of the residual risk process.
EPA believes the potential cost savings produced by allowing the
burning of condensed steam stripper vent gases would be significant.
Industry estimates that annual cost savings would be approximately
$850,000 per mill, or $100 million for the entire kraft industry. Cost
savings would come primarily through the reduction in fossil fuel
purchases.
C. Kraft New Source Performance Standards
EPA is considering whether the New Source Performance Standards
(NSPS) for kraft mills and the proposed pulp and paper NESHAP standards
may have some overlapping or redundant requirements. Possible areas of
overlap in the two regulations are affected sources or emission points,
monitoring, recordkeeping, and reporting requirements. EPA solicits
comments on the potential overlap of the kraft NSPS and the proposed
NESHAP standards.
The kraft NSPS established emission limits for PM and total reduced
sulfur TRS compounds for the following new or modified emission sources
located at kraft mills: recovery furnaces, digesters, multiple effect
evaporators, lime kilns, brownstock washers, black liquor oxidation
systems, condensate stripper systems, and smelt dissolving tanks. The
pulp and paper NESHAP will establish national limits for total HAP
emissions from the following sources at all types of new or existing
chemical pulping mills: digester, evaporator, turpentine recovery,
brown stock washer, and condensate stripper systems. Total reduced
sulfur and HAP compounds are found in the process vents affected by
both the NSPS and NESHAP regulations.
The kraft NSPS requires monitoring of the following parameters:
opacity from the recovery furnace, TRS emissions from affected points,
incinerator temperature, and process variables for any scrubber used
for controlling
[[Page 9398]]
emissions from a lime kiln or smelt dissolving tank. The NESHAP
requires monitoring of the following parameters or pieces of equipment:
closed vent system, combustion device temperature, scrubber, steam
stripper, biological treatment, and the wastewater collection system.
While the NSPS requires monitoring of TRS emissions for the most part,
the NESHAP focuses on monitoring the performance of specific pieces of
equipment.
Recordkeeping duties specified in the NSPS include logging of daily
opacity and TRS emissions data. For the specified collection or control
devices used to comply with the NESHAP, the monitoring parameters
identified in the rule must be recorded in a manner consistent with the
General Provisions. EPA solicits data and comments on whether these
different approaches create unnecessarily redundant or overburdensome
monitoring or recording requirements.
The NSPS requires semi-annual reporting detailing the periods of
excess emissions. Quarterly reports regarding excess emissions and
continuous monitoring system performance are currently required by the
proposed NESHAP. The NESHAP reporting frequencies are currently under
review and will be revised to be no more stringent than the
requirements specified in the General Provisions. Additionally, the
NESHAP requires exceedance reports for startups, shutdowns, or
malfunctions that are inconsistent with the source's specified
operating procedures. One option under consideration by EPA is to allow
the facility to comply with the NESHAP in lieu of complying with the
NSPS for certain pieces of process equipment. EPA solicits data and
comments on the extent to which these reporting requirements could or
should be combined or reduced.
X. Standards for Mechanical Mills, Secondary Fiber Mills, Nonwood Mills
and Paper Machines
A. Presumptive MACT Process
As previously mentioned in the Background Section, a Presumptive
MACT was issued for the MACT III (i.e. mechanical wood pulping mills,
secondary fiber deinking and nondeinking mills, nonwood pulping mills,
and paper machines) source category in September of 1995. Presumptive
MACT is an estimate of MACT based on an assessment of readily available
information and through consultation with experts in State and local
agencies, EPA, environmental groups, and the regulated industry. A
primary purpose for Presumptive MACT is to assist State and local
agencies, industry, and the public in Section 112(g) case-by-case MACT
determinations and with the Section 112(j) hammer provision standards.
The process is useful to enhance planning in the standards development
process. Through the Presumptive MACT process issues can be identified
and resolved early in the standards development process; the
``stakeholders'' can be identified; and the best method to develop MACT
can be determined (e.g., traditional regulatory development, Adopt-A-
MACT, Share-A-MACT, or proposing the Presumptive MACT as MACT).
B. Summary of the Presumptive MACT for MACT III Sources
For the MACT III source category, EPA contacted representatives of
major industry, State, and environmental groups and held discussions
with a team of State and industry representatives. The team evaluated
the information that was available and established the Presumptive
MACT. The pulp and paper Presumptive MACT is available on the Office of
Air Quality Planning and Standards Technology Transfer Network (TTN)
under the Clean Air Act Amendments, Title III Policy and Guidance
Bulletin Board. The Presumptive MACT document is also available in the
docket (see SUPPLEMENTARY INFORMATION section).
Limited information on the source category was identified during
the Presumptive MACT process. The available information identified four
potential sources for HAP emissions: pulping, wastewater from the
pulping process, bleaching, and paper making. Of these, chlorine
bleaching would be a likely source of HAP emissions, assuming
operations in use are similar to those used by bleach plants at
chemical wood pulping mills. Paper machines were also considered an
emission source because of the use of paper additives and solvents.
Nonwood pulping processes and the associated wastewater are potential
sources of HAP emissions based on similarities between these and
chemical wood pulping operations; however, the magnitude of the
emissions could not be determined for these or the other potential
sources from the available information. Information indicated secondary
fiber deinking and nondeinking mills are not a significant source of
HAP emissions (Docket A-95-31 item II-B-1).
Information on current control practices suggests the mills have no
add-on controls in place for HAP emissions except on chlorine
bleaching. There are, however, a number of control options that can be
considered. Besides the add-on controls at bleach plants (scrubbers
that remove chlorine and hydrogen chloride) chlorine-free bleaching may
be in use at some mills. Methanol emissions from paper machines
resulting from recycled water from the pulping process are to be
addressed by the chemical wood pulping standards (see section IV
Definition of Source); however, emissions from paper machines that
result from the use of paper additives and solvents were addressed by
the Presumptive MACT. The Presumptive MACT suggested these emissions
may be reduced through substituting additives and solvent for nonHAP or
lower-HAP alternatives. MACT III for pulping operations, low volume-
high concentration gas streams may be routed to a combustion device (as
would be required in the MACT I discussed earlier in this notice).
Lastly, high concentration wastewater streams may be treated through
biological treatment or by steam stripping of the HAP and controlling
emissions from the steam stripper.
One of the conclusions of the Presumptive MACT was to proceed with
MACT standard development through the traditional rulemaking process.
EPA has since reconsidered this position, given the findings during the
Presumptive MACT process and EPA's current budget limitations. EPA has
now decided to propose the Presumptive MACT as MACT.
C. Area/Major Source Discussion
No information was identified during the Presumptive MACT process
to suggest area sources associated with the MACT III source category
warrant listing as a category of area sources, pursuant to Section
112(c)(3) of the Act. Consequently, only major sources were evaluated
for this category. EPA also has no evidence that any facilities that
are solely nonwood mills are major emission sources in and of
themselves. Major sources are sources within a contiguous area that
emit or have a potential to emit, 10 tpy or more of any HAP or 25 tpy
or more of any combination of HAP. Industry has published information
in an NCASI Technical Bulletin, Number 677 (Docket A-95-31 item II-D-
13), on two emission points at a thermomechanical pulping mill. The two
emission points were the refiner condenser vent and the chip steaming
condenser vent. Total HAP emissions estimated from the two points
tested at this mill were approximately 8 tons per year. It is not
[[Page 9399]]
known if remaining emission points not tested at this mill emit enough
additional HAP to be a major source, or if a larger thermomechanical
mill would be a major source. NCASI also published a Technical
Bulletin, Number 649 (Docket A-95-31 item II-D-12) on emissions from
operations that bleach and brighten secondary fibers. This bulletin was
based on sampling conducted in 1991 and 1992. Due to an increase in the
demand for secondary fiber, these mills have increased in size since
the 1991/1992 sampling program. Therefore, large stand alone secondary
fiber mills may exist that have HAP emissions large enough to be major
sources. Where these MACT III mills are collocated at kraft, sulfite,
semi-chemical, and soda mills that are major sources, they will be
subject to MACT standards; however, the only emission sources that
would be affected by the MACT III proposed standard are the MACT III
bleach plants and possibly the paper machines (for emissions resulting
from solvent or additive use). EPA knows of no additional bleach plants
that would be subject to MACT standards because of their collocation at
a MACT I mill that is a major source. Paper machines will only be
affected if EPA decides to establish additive and/or solvent
substitution as MACT.
D. Proposed MACT III
The information gathered during the Presumptive MACT process
indicates that there are no air pollution control devices in place on
MACT III sources except for chlorine bleaching processes. Based on this
finding, the floor for these sources is no control. Further, available
information indicates any add-on controls would not be cost effective
for these sources. Therefore, EPA has decided not to require controls
beyond the floor. The MACT proposed here for the MACT III sources is no
add-on controls for pulping and the associated wastewater, paper
machines, and nonchlorine bleaching.
Bleach plants at MACT III sources collocated with MACT I sources
are presently regulated under the MACT I standard (see Section VI.E,
Level of Standards). Based on information provided by industry, EPA
believes traditional bleach plants using chlorinated bleaching agents,
such as those found at Kraft mills, that are located at stand-alone
MACT III mills are presently controlled with scrubbers that remove
chlorine and hydrogen chloride for process or worker safety reasons.
EPA is not aware of any better control that could be used. Therefore,
control of air emissions from these bleach plants is already in place
and the proposed MACT for bleach plants at stand-alone MACT III
facilities is no additional control.
EPA is proposing no MACT standard for chemical additives and
solvents at paper machines at this time. EPA continues to investigate
the use of HAP chemicals in papermaking, the magnitude of HAP
emissions, and the viability of chemical substitution that would reduce
HAP emissions. An example of chemical substitution is substitution of
HAP-containing additives and solvents with lower HAP or non-HAP organic
compounds. If information becomes available regarding the floor or
cost-effective HAP controls beyond the floor, EPA will propose a MACT
standard for additive and solvent usage on paper machines in the
future.
E. Request for Information
Additional information is being collected by industry groups, which
began a testing program in September 1995. This program is designed to
evaluate emissions from mechanical pulping processes, secondary fibers
pulping processes, and paper machines. Industry plans to have the
report on this sampling program available in January of 1997. EPA has
also requested any available information on HAP emissions from nonwood
mills from States with these mills; however, limited data are expected
to be available. EPA is requesting any information on uncontrolled
bleaching using chlorinated bleaching agents at stand-alone MACT III
sources. To supplement the information collected during the Presumptive
MACT and the more recent industry and EPA efforts, EPA is requesting
data and comments on its proposal for the MACT III source category.
List of Subjects in 40 CFR Part 63
Air pollution control, Hazardous air pollutants, Pulp and paper
mills.
Dated: March 1, 1996.
Richard S. Wilson,
Assistant Administrator for Air and Radiation.
[FR Doc. 96-5397 Filed 3-7-96; 8:45 am]
BILLING CODE 6560-50-P
