[Federal Register Volume 59, Number 160 (Friday, August 19, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-20441]
[[Page Unknown]]
[Federal Register: August 19, 1994]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 63
[AD-FRL-5054-2]
National Emission Standards for Hazardous Air Pollutants for
Source Category: Gasoline Distribution (Stage I)
AGENCY: Environmental Protection Agency (EPA).
ACTION: Announcement of the availability of supplemental information,
and reopening of public comment period on the supplemental information.
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SUMMARY: On February 8, 1994 (59 FR 5868), the EPA proposed standards
(the proposal or proposed standards) to limit emissions of hazardous
air pollutants (HAP's) from existing and new bulk gasoline terminals
and pipeline breakout stations under section 112 of the Clean Air Act
as amended in 1990 (Act). The public comment period on the proposed
rule ended April 11, 1994. This action announces the availability of
supplemental information and the reopening of the comment period for
comment on only the supplemental information. This supplemental
information was provided during the comment period on the proposal and
pertains to the level of control and test procedures for tank truck
leakage. The EPA plans to consider comments received on this action,
along with the comments received on the proposal, and take final action
on the rule on November 23, 1994 as required under consent decree. Due
to this short schedule, only a 30-day comment period is being provided
and no public hearing will be held.
DATES: Comments must be received on or before September 19, 1994.
ADDRESSES: Comments. Comments should be submitted (in duplicate, if
possible) to: Air Docket Section (6102), ATTN: Docket No. A-92-38, Room
M1500, U.S. Environmental Protection Agency, 401 M Street, SW.,
Washington, DC 20460, and Mr. Stephen Shedd, address shown in FOR
FURTHER INFORMATION CONTACT section of this notice.
Docket. Docket No. A-92-38, containing supporting information used
in developing the proposed standards, public comments received on the
proposal, and the test procedures and methods discussed in today's
notice, is available for public inspection and copying between 8:30
a.m. and 3:30 p.m., Monday through Friday, at the EPA's Air Docket
Section, Waterside Mall, Room 1500, 1st Floor, 401 M Street, SW,
Washington, DC 20460. A reasonable fee may be charged for copying.
FOR FURTHER INFORMATION CONTACT: For information concerning today's
notice, contact Mr. Stephen Shedd at (919) 541-5397, Chemicals and
Petroleum Branch, Emission Standards Division (MD-13), U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711.
SUPPLEMENTARY INFORMATION: On February 8, 1994 (59 FR 5868), the EPA
proposed standards to limit emissions of hazardous air pollutants
(HAP's) from existing and new bulk gasoline terminals and pipeline
breakout stations under section 112 of the Act. Two comment letters
presented information on California standards for tank truck leaks at
existing facilities that are more stringent than those standards
proposed by the EPA. The EPA proposed that tank trucks and railcars
annually pass a pressure and vacuum test before loading gasoline at
existing and new major source facilities. The California standards have
a more stringent requirement for the annual test, an additional annual
test for internal vapor valves, and a year-round leak rate requirement
and test procedures. Additionally, the EPA proposed for new facilities
the use of a loading rack vacuum assist system, in addition to the
proposed annual pressure and vacuum test, to further control leakage
from tank trucks and railcars. The EPA did not analyze nor fully
discuss these California standards during development of the proposal
or at proposal. The purpose of this notice is to announce and discuss
the consideration of these additional standards. Below is a discussion
of the California standard for tank truck leakage and the EPA's
consideration of that information. As noted in the ADDRESSES section of
today's notice, the docket (Docket No. A-92-38) contains the California
test procedures and methods discussed below.
The California Air Resources Board (ARB) and the California air
pollution control districts have been implementing tank truck leakage
standards since the late 1970's. Currently all tank trucks transporting
gasoline in California, including tank trucks from neighboring States
that operate in California, must meet the California standards. In
summary they include three major standards, an annual certification and
a year-round standard for the tank and its vapor piping and hoses and a
year-round pressure standard for the tank truck's internal vapor valve.
The annual certification standards include initially pressurizing and
later evacuating the tank and associated vapor piping and hoses, to 18
inches of water and to 6 inches of water, respectively. In 5 minutes
the allowable pressure change can be no more than the values shown in
Table 1. The EPA's Control Techniques Guideline (CTG) document and New
Source Performance Standards (NSPS) (40 CFR part 60, subpart XX)
contain annual pressure and vacuum test levels of initial pressures and
test duration which are the same as California's. However, a less
stringent pressure change of 3 inches of water column is allowed for
all tank trucks under the NSPS, CTG, and proposal.
Table 1. Allowable Tank Pressure Change
------------------------------------------------------------------------
Allowable pressure change
per tank or compartment
tested (inches of water,
gauge, per 5 minutes)
Tank or compartment capacity (gallons) --------------------------
Year-round
Annual (not to be
certification exceeded
anytime)
------------------------------------------------------------------------
2,500 & Up................................... 1 2.5
2,499-1,500.................................. 1.5 3.0
1,499-1,000.................................. 2.0 3.5
999-less..................................... 2.5 4.0
------------------------------------------------------------------------
Table 1 presents a year-round allowable pressure change standard
that is 1.5 inches of water column higher than annual certification
allowable pressure change. This year-round standard is periodically
demonstrated by a combustible gas detector method or the annual
certification test procedure (using the allowable year-round pressure
change value) by owners and operators and used by the California ARB
and districts for audits and compliance, respectively. Combustible gas
detectors are easy to use and transport and can be used in the field
while trucks are loading gasoline. The annual certification pressure/
vacuum test procedure requires the tank to be taken out of gasoline
service and requires more test equipment than the combustible gas
detector method. Therefore, the combustible gas detector method
provides an easy-to-use field compliance procedure. Tank trucks with a
leak found above 100 percent of the lower explosive limit (LEL) on a
combustible gas detector are required to be taken out of service until
they pass the allowable year-round pressure change using the annual
certification test method. If the truck fails both tests, the truck
owner is fined and the tank is not allowed to return to service until
it meets the annual certification standard. Those tanks found to have
leaks above 100 percent of the LEL and found to meet the year-round
allowable pressure change with the annual certification test procedure
are not penalized if maintenance is not performed before the pressure
test. A similar combustible gas detector procedure was presented in the
EPA's CTG, but is not contained in the NSPS or this proposed NESHAP.
However, some other States and oil companies are using this detector
procedure as a compliance method, in addition to the annual pressure
and vacuum tests. The Bay Area Air Quality Management District (BAAQMD)
developed a field pressure test procedure that measures the pressure
change without taking the tank out of service. Nitrogen gas is used to
pressurize the tank's vapor head space. This field pressure test method
was determined by the California ARB in 1986 to be equivalent to the
combustible gas detector method. Since 1986, the BAAQMD has implemented
a comprehensive outreach program with the field pressure test.
Operators are instructed in the field test procedure, and participate
in an ongoing inspection and maintenance program. Participation is
voluntary, and the incentive is to reduce the penalties for violations
by having documentation showing a history of regular tests and
maintenance on the tank truck.
The third California standard for tank trucks is the annually
tested certification pressure test on the tank truck's internal vapor
valve. This valve provides a seal between the truck's tank and its
vapor piping and connected hose. For this test, the tank and associated
vapor piping and hose are pressurized to 18 inches of water column, and
the valve is then closed. Then, while leaving the tank under pressure,
the pressure in the tank truck's vapor collection piping and vapor hose
is released to atmospheric pressure and then capped. After 5 minutes, a
pressure increase of no more than 5 inches of water column is allowed
to occur downstream of the valve in the tank truck's vapor piping and
hose. Any pressure increase indicates that the valve is leaking. This
leakage would eventually be released to the atmosphere when the vapor
hose and piping are not connected to a vapor collection system. This
standard for internal vapor valves is not contained in the CTG, the
NSPS, or the proposed standard.
The California ARB is currently revising its tank truck standards
to change the level of the annual test and is updating its test
procedures and methods. The BAAQMD tested 200 tank trucks and found
that 86 percent of the trucks could pass a 0.25-inch standard and 91
percent could pass a 0.5-inch standard. The California ARB proposed
that the allowable annual certification's allowable pressure change be
reduced by 50 percent (1-inch drop is proposed to be reduced to a 0.5-
inch, etc.). Besides general updating and clarifications of the test
procedures and methods, the California ARB is adding the field pressure
test used by BAAQMD in the ARB certification procedures.
Under section 112 of the Act, the minimum baseline (floor) at which
standards may be set, for existing sources, is the ``average emission
limitation achieved by the best performing 12 percent of the existing
sources''(section 112(d)(3) of the Act). The existing California
standards are used statewide and on tank trucks from surrounding areas.
California is estimated to account for nearly 12 percent of the
national gasoline consumption. Since trucks in California and
surrounding areas transport about 12 percent of the national gasoline,
it is logical to assume that this represents about 12 percent of the
affected gasoline tank truck population. The EPA looks at emission
limitations achieved by each of the best performing 12 percent of
existing sources, and average those limitations (59 FR 29196).
``Average'' is interpreted to mean a measure of central tendency such
as the arithmetic mean or median. In the case of the California
standards, nearly or about 12 percent of tank trucks at least meet or
exceed the California standards, therefore these standards are at least
the arithmetic average, and certainly the 94 percentile or median.
Additionally, the existing California standards achieve the lowest
emission limitation (in this case by achieving the lowest leakage
rates) and are the best performing of existing sources. Thus, the EPA
now considers the existing California standards as the existing source
floor since they represent the average emission limitation achieved by
the best performing 12 percent of the existing sources.
The EPA proposal contains a requirement to operate a vacuum assist
system at new source facilities. The agency proposed this requirement
for new sources based on the system providing ``emission control that
is achieved in practice by the best controlled similar source''
(section 112(d)(3) of the Act). Many commenters questioned the amount
of emission control that would be achieved by the vacuum assist system.
In the EPA's consideration of the vacuum assist system as the floor for
new sources, the EPA will also consider the existing California
standards discussed earlier.
Through consideration of comments received on today's notice along
with those on the proposed rule, the EPA will determine the control
levels to be applied to tank truck leakage. Today's opening of the
comment period is only for taking comment on the supplemental material
contained in this notice on tank truck vapor leakage controls.
Specifically, the EPA is requesting comments and data on the
consideration of the existing California standards as the floor level
of control for new and existing facilities as required under section
112 of the Act. The EPA is also requesting comment on whether the level
of control for tank trucks at new and existing facilities should be
based on the existing or the proposed California standards. Comments
are also requested on the use and accuracy of the test procedures and
methods referred to earlier and provided in the docket, including both
the existing and updated or revised procedures and methods.
Dated: August 4, 1994.
Mary D. Nichols,
Assistant Administrator, Office of Air and Radiation.
[FR Doc. 94-20441 Filed 8-18-94; 8:45 am]
BILLING CODE 6560-50-P
