National Emission Standards for Hazardous Air Pollutants for
Source Categories: Gasoline Distribution (Stage I)
[Federal Register: December 14, 1994]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 9 and 63
[AD-FRL-5116-5]
RIN 2060-AD93
National Emission Standards for Hazardous Air Pollutants for
Source Categories: Gasoline Distribution (Stage I)
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
SUMMARY: The final rule provided in this document is a national
emission standard(s) for hazardous air pollutants (NESHAP) for bulk
gasoline terminals and pipeline breakout stations pursuant to section
112 of the Clean Air Act as amended in 1990 (the Act). On February 8,
1994, EPA proposed a NESHAP for the gasoline distribution source
category. On August 19, 1994, the EPA also published supplementary data
and recommendations on the level of control for gasoline cargo tanks.
This document announces the EPA's final decisions on the rule.
This final rule requires sources to achieve emission limits
reflecting application of the maximum achievable control technology
(MACT) consistent with section 112(d) of the Act. The rule regulates
all hazardous air pollutants (HAP's) identified in the Act's list of
189 HAP's that are emitted from new and existing bulk gasoline
terminals and pipeline breakout stations that are major sources of
HAP's or are located at plant sites that are major sources of HAP's.
DATES: Effective Date. December 14, 1994.
Judicial Review. Under section 307(b)(1) of the Act, judicial
review of NESHAP is available only by filing a petition for review in
the U.S. Court of Appeals for the District of Columbia Circuit within
60 days of today's publication of this final rule. Under section
307(b)(2) of the Act, the requirements that are the subject of today's
notice may not be challenged later in civil or criminal proceedings
brought by the EPA to enforce these requirements.
ADDRESSES: Docket. Docket No. A-92-38, containing information
considered by the EPA in developing the promulgated standards, is
available for public inspection and copying between 8 a.m. and 4 p.m.,
Monday through Friday, including all non-Government holidays, at the
EPA's Air and Radiation Docket and Information Center, room M1500, U.S.
Environmental Protection Agency, 401 M Street, SW., Washington, DC
20460; telephone (202) 260-7548. A reasonable fee may be charged for
copying.
Background Information Document. The background information
document (BID) for the promulgated standards may be obtained as
supplies permit from the U.S. Environmental Protection Agency Library
(MD-35), Research Triangle Park, North Carolina 27711, telephone (919)
541-2777; or from the U.S. Department of Commerce, National Technical
Information Service (NTIS), Springfield, Virginia 22161, telephone
(703) 487-4650. Please refer to ``Gasoline Distribution Industry (Stage
I)--Background Information for Promulgated Standards'' (EPA-453/R-94-
002b). The BID contains: (1) a summary of the public comments made on
the proposed standards and the EPA's responses to the comments, and (2)
a summary of the revisions made to the regulatory analysis presented at
proposal. Electronic versions of the BID as well as this preamble and
final rule are available for download from the EPA's Technology
Transfer Network (TTN), a network of electronic bulletin boards
developed and operated by the 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 up to a 14,400 bits
per second (bps) modem. If more information on TTN is needed, contact
the systems operator at (919) 541-5384.
FOR FURTHER INFORMATION CONTACT: For general and technical information
concerning the final rule, contact Mr. Stephen Shedd, Waste and
Chemical Processes Group, Emission Standards Division (MD-13), U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711; telephone (919) 541-5397. For information regarding the economic
impacts of the rule, contact Mr. Scott Mathias, Innovative Strategies
and Economics Group, Air Quality Strategies and Standards Division, at
the above address; telephone (919) 541-5310. For information regarding
the test methods and procedures referenced in the rule, contact Mr. Roy
Huntley, Emission Inventory and Factors Group, Emissions, Monitoring
and Analysis Division, at the above address; telephone (919) 541-1060.
SUPPLEMENTARY INFORMATION: The information presented in this preamble
is organized as follows:
I. Applicability
II. Summary of Major Changes Since Proposal
A. Applicability
B. Level of Control
III. Significant Comments and Changes
A. Applicability Determination
B. Equipment Leak Requirements
C. Storage Vessel Requirements
D. Cargo Tank Requirements
E. Continuous Monitoring
IV. Summary of the Final Rule
A. Sources Covered
B. Standards for Sources
C. Effective Date for Compliance
D. Compliance Extensions
E. Compliance Testing and Monitoring
F. Recordkeeping and Reporting
V. Administrative Requirements
A. Docket
B. Executive Order 12866
C. Paperwork Reduction Act
D. Regulatory Flexibility Act
E. Regulatory Review
I. Applicability
The final rule is applicable to all existing and new bulk gasoline
terminals and pipeline breakout stations that are major sources of
HAP's or are located at plant sites that are major sources. Major
source facilities that are subject to this rule must install and
operate the control equipment and implement the work practices required
in the rule. Section 112(a) of the Act defines major source as a
source, or group of sources, located within a contiguous area and under
common control that emits or has the potential to emit, considering
controls, 10 tons per year (tpy) or more of any individual HAP or 25
tpy or more of any combination of HAP's. Area sources are stationary
sources that do not qualify as ``major.'' The term ``affected source''
as used in this rule means the total of all HAP emission points at each
bulk gasoline terminal or pipeline breakout station that is subject to
the rule.
To determine the applicability of this rule to facilities that are
within a contiguous area of other HAP-emitting emission sources that
are not part of the source category covered by this rule, the owner or
operator must determine whether the plant site as a whole is a major
source. A formal HAP emissions inventory must be used to determine if
total HAP emissions from all HAP emission sources at the plant site
meets the definition of a major source. To determine the applicability
of this rule to facilities that are not contiguous with other HAPemitting
emission sources (i.e., to stand-alone bulk gasoline terminals
or pipeline breakout station facilities), the owner or operator may use
the emissions screening equations in the rule, which are intended to
identify clearly nonmajor (area) sources, or conduct a formal HAP
emissions inventory.
Certain assumptions used by all nonmajor sources in the emission
screening equations will become enforceable limitations on the
facility's operations under this rule. These enforceable limitations
include, type of gasoline used, type and number of storage vessels,
limit on gasoline throughput, level of cargo tank vapor-tightness, and
number of valves, pumps, connectors, loading arm valves, and open-ended
lines in gasoline service. Federally enforceable limitations must be
established outside the provisions of this rule, for facilities using
the emissions inventory for determination of their major source status,
and for some parameters used by facilities in the emission screening
equation. The vapor processor outlet emission limit for cargo tank
emissions and minimum efficiency for fixed roof storage vessel
emissions are the federally enforceable limitations that must be
established outside the provisions of this rule to be used in the
emission screening equations. Facilities using the emission screening
equations in the rule are required to record their assumptions and
calculations, notify the Administrator that the facility is using the
screening equations and provide the results of the calculations, and
operate the facility in a manner not to exceed the operational
parameters used in the calculations. Larger facilities (those that, in
and of themselves, have HAP emissions over 50 percent of the major
source emissions thresholds above and use the emissions screening
equations in the rule) are additionally required to submit to the
Administrator for approval their assumptions and calculations, maintain
records to document the parameters have not been exceeded, and submit
an annual certification that the operational parameters established for
the facility have not been exceeded.
II. Summary of Major Changes Since Proposal
On February 8, 1994 (59 FR 5868), the EPA proposed NESHAP for all
major source bulk gasoline terminals and pipeline breakout stations and
provided notice of a public hearing on the proposal. A public hearing
was held on March 10, 1994, and the 60-day comment period ended on
April 11, 1994. On August 19, 1994 (59 FR 42788), the EPA published an
announcement of the availability of supplemental information pertaining
to the level of control and test procedures for cargo tank leakage, and
established a comment period for this information. Public comments
received in response to the proposal and the supplemental notice have
been considered in this final rulemaking action.
In response to comments received on the proposed standards, changes
have been made in developing the final rule. While several of these are
clarifying changes designed to make the Agency's intent clearer, a
number of them are significant changes to the proposed control
requirements of the standards. Substantive changes made since proposal
are described in the following sections. The Agency's responses to
public comments that are not addressed in this preamble and the revised
analysis for the final rule are contained in the BID for this final
rulemaking (see ADDRESSES section of this document).
A. Applicability
The constants in the proposed emission estimation screening
equations have been modified based on lower emission factors for
leakage emissions from tank trucks and equipment components. In
addition, the storage vessel constants have been recalculated using the
current EPA emission equations (publication AP-42, Section 12) to
estimate evaporative emissions from the storage of gasoline. Finally,
an adjustment factor has been added to each equation to account for
facilities that do not handle any reformulated or oxygenated gasoline
containing methyl tert-butyl ether (MTBE).
For the purposes of this rulemaking and under certain conditions,
the EPA has determined that a bulk gasoline terminal or pipeline
breakout station facility's ``potential to emit'' (PTE) may be based on
certain operating limitations that are made enforceable under this
rule. These limitations would be established in the range between
actual and maximum design conditions based on emission screening
equations provided in the rule. If a facility's operation (e.g.,
gasoline throughput) exceeds these limitations or if a facility fails
to maintain records or report as required in this final rule, it will
be considered to be in violation of the rule.
B. Level of Control
The proposed leak detection and repair (LDAR) requirements for
controlling equipment leaks have been replaced with a visual inspection
program. Instrument leak detection and repair will be an available
alternative rather than the basis of the final rule. Both new and
existing major sources are required to perform a visual leak inspection
of their equipment on a monthly basis.
At proposal, the ``floor,'' or minimum level of control for
gasoline storage vessels at existing facilities was determined to be
the requirements in 40 CFR part 60, subpart Kb, the new source
performance standards (NSPS subpart Kb) which apply to new volatile
organic liquid storage vessels. Based on the revised analysis, a new
floor for storage vessels has been determined. Only the storage vessel
floating roof closure device or ``rim seal'' requirements in the NSPS
subpart Kb are now considered to be the floor for existing storage
vessels. Gasketed ``fittings'' (such as hatch covers, vents, drains,
etc.), which are also an NSPS subpart Kb requirement, are not now
considered to be a part of the floor for this rule. However, in the
final rule gasketed fittings are required to be installed on existing
external floating roof storage tanks that do not meet the NSPS subpart
Kb rim seal requirement, as of today's date.
The floor level of control and the control requirements for leakage
from controlled cargo tanks (tank trucks and railcars) at existing and
new major source bulk terminals have been changed so that cargo tanks
must annually pass a certification test with a 25 mm (1 inch) of water
pressure decay limit [in 5 minutes, after pressurization to +460 mm
(+18 inches) of water column and then evacuation to -150 mm (-6 inches)
of water] instead of the 75 mm (3 inch) of water pressure decay
proposed limit. In addition, cargo tank owners and operators are
required to annually perform a pressure test of the cargo tank's
internal vapor valve and to be able to meet a 63 mm (2.5 inch) pressure
change limit at any time. Test procedures to be used in performing
these tests are added to the final rule. At proposal, new bulk gasoline
terminals were required to install and operate a vacuum assist vapor
collection system to minimize cargo tank leakage. The requirement for
vacuum assist has been replaced with the same leak testing requirements
described above for cargo tanks that load at existing facilities.
III. Significant Comments and Changes
Comments on the proposed standards and the supplemental notice were
received from industry, State and local air pollution control agencies,
trade associations, an environmental group, and a U.S. Government
agency. A detailed discussion of comments and the EPA's responses can
be found in the promulgation BID, which is referred to in the ADDRESSES
section of this document. The major comments, responses, and changes
made to the rule since proposal are discussed below.
A. Applicability Determination
Screening Equations
Several commenters felt that the EPA did not fully explain or
support the development of the proposed emission estimation screening
equations. As a result, these two equations were characterized by some
commenters as arbitrary. One commenter who had experience preparing
emissions inventories for bulk gasoline terminals in Texas pointed out
that, for several terminals that do not exceed the 10/25 tons of HAP's
per year threshold, the screening equation incorrectly indicates that
many of these terminals emit greater than 10/25 tons of HAP's.
The development of the screening equations was discussed in the
preamble to the proposed standards. This development was explained in
more detail in a memorandum that was included at proposal in the
rulemaking docket (item II-B-23), and has been updated and included in
the final docket. These equations were not arbitrary, but were
developed specifically to identify facilities that have the potential
to emit (PTE) less than 10/25 tons per year of HAP and to reduce the
amount of effort needed to perform applicability determinations.
However, if a facility has other HAP emission sources not considered in
the equation, the equation will under-predict emissions and cannot be
used to determine if the facility is a major source. Some commenters
expressed support for the use of screening equations as an aid in
determining rule applicability, but most of them had suggestions for
revising the equations to make them more accurate and useful. In
response to all of these comments, the equations have been retained in
the rule but have been revised to accommodate the concerns of
commenters and to make them more accurate in their function as a
screening tool. These modifications and the new equations are discussed
in detail in the responses to the following comments.
Some commenters suggested that, instead of using ``worst-case''
HAP-emitting gasolines to derive the constants in the equations, the
Agency should use average parameters to promote consistency between the
equations and the rule. Also, the EPA should include an adjustment
factor for facilities that do not handle gasoline oxygenated with MTBE.
At proposal, the EPA developed the screening equations based on a
HAP to VOC ratio that was determined to represent the average MTBE
content in reformulated and oxygenated gasolines, and not the ``worstcase''
ratio. In the gasoline composition analyses that were available
to the Agency before proposal, the MTBE content in gasoline ranged from
11.8 to 16.3 percent. Based on these data, the EPA made an assumption
that the average MTBE content of reformulated and oxygenated gasolines
was 11.9 percent, which is slightly higher than the lowest percentage
found in the data. In addition, the EPA assumed that most facilities
that handle higher MTBE content oxygenated gasolines would also handle
the lower MTBE content reformulated gasolines. This approach is
consistent with the Agency's intent to avoid underestimating emissions
in this screening process, which could allow a major source to be
deemed an area source and thus improperly escape applicability of this
rule. Facilities in any case will have the opportunity to perform a
full emissions inventory in order to make a more accurate determination
of their status.
The EPA agrees that the proposed emission factors overestimate HAP
emissions from facilities handling gasoline without MTBE. As a result,
an adjustment factor has been included in the screening equations for
facilities in this situation. Facilities that handle, or anticipate
handling, any oxygenated or reformulated gasoline containing MTBE as a
component will not use the adjustment factor in performing the
calculations.
Several commenters felt the EPA's assumption that annually
certified and tested tank trucks with vapor control lose 10 percent of
the displaced vapors through leakage while loading is too high. The EPA
has reevaluated the basis for its assumption that tank trucks in an
annual test program lose 10 percent of the displaced vapors as leakage
emissions. The EPA has calculated a new leakage rate that is much lower
than the proposed figure, and this calculation is discussed in Section
III.D.1 of this notice.
Commenters stated that fixed-roof storage vessels connected to a
vapor control device emit virtually no HAP's and that a term should be
added to represent and quantify the low emission levels from such
controlled tanks. The EPA agrees with the commenters and has added a
new expression, (1-CE), to both screening equations. The term ``CE''
represents the control efficiency of the control device used to process
vapors from the fixed-roof tank. The value of CE must be documented by
the facility as meeting the definition of federally enforceable in
subpart A of 40 CFR part 63 (General Provisions). If the facility is
not controlling emissions from its fixed-roof tanks using a vapor
control device, a value of zero will be entered for the term ``CE.''
Several commenters felt that the emission factors used for pump
seals and valves were too high, based on recent data collected at
marketing facilities. The EPA has evaluated the new data and agrees
with this comment. The emission factors for pump seals and valves have
been revised as discussed under Section III.B.1 of this notice.
Commenters felt that the equations should provide emission credits
for facilities that have implemented an instrument LDAR program or
vacuum assist vapor collection. Data provided by industry show that the
use of visual inspection programs is just as effective as the use of
instrument LDAR in identifying equipment leaks at marketing terminals
and breakout stations, as discussed further in Section III.B.2 of this
notice. As a result, the EPA will not grant credits to facilities that
currently use an LDAR program. The EPA has decided to not require
vacuum assist as explained in Section III.D.2.a of this notice, due to
Agency concerns about the control effectiveness of vacuum assist
technology at bulk terminal loading racks. As a result, the EPA also
will not provide emission credits for any facility using vacuum assist
technology.
One commenter stated that emission standards or limitations more
stringent than the Federal NSPS (40 CFR part 60, subpart XX) limit (35
mg/liter) should be recognized. The term ``EF'' in the screening
equation for bulk terminals applies to any federally enforceable
emission standard in effect for the vapor processor. The concept of
``federally enforceable,'' defined in Sec. 63.2, allows emission
standards or limitations more stringent than the NSPS limit.
One commenter believed that the screening equations should be
modified to account for storage vessels that store MTBE for infrequent
periods and durations. The EPA does not intend to regulate under this
rule storage vessels that store only MTBE or any other gasoline
component or additive. All the other non-gasoline liquids such as MTBE
will be studied for regulation under the forthcoming NESHAP source
category of ``Non-Gasoline Liquid Distribution'' under section 112 of
the Act.
Commenters requested guidance on how to estimate emissions from
``swing'' tanks, which store gasoline only part of the time. In keeping
with the intent of these equations as an emission estimation screening
tool, the EPA has made the simplifying assumption that vessels storing
gasoline for any period or periods during a year will be assumed to
store gasoline year round. As a result, the emissions from ``swing''
tanks will be estimated in the same way as for tanks that store
gasoline on a continuous basis. Owners and operators should use the
emissions inventory approach, as specified in Sec. 63.420(a)(2) and
(b)(2), if these assumptions lead to a significant overestimation of
HAP emissions at their facility.
Emissions Inventory
As a supplement to the emission estimation screening equations,
Sec. 63.420(a)(2) and (b)(2) of the proposed rule exempted those
facilities ``for which the owner or operator has documented to the
Administrator's satisfaction that the facility is not a major source as
defined in section 112(a)(1) of the Clean Air Act.'' The proposal
preamble on page 5877 indicated that an ``emissions audit'' would have
to be performed to satisfy these provisions. One commenter felt that
the rule provisions should specifically state that the estimation of
emissions for the applicability determination is to be accomplished by
means of an emissions audit, as was stated in the preamble. Several
other commenters found the term ``emissions audit'' confusing, and
questioned what the EPA would consider acceptable for demonstrating
applicability. Some suggested that the familiar term ``emission
inventory'' be substituted because emission inventories are common
requirements and procedures are in place under many State programs.
Others requested that the EPA define or provide an approved methodology
for conducting the emissions audit. One commenter said that the public
should have an opportunity to comment on this guidance prior to this
rule being promulgated. One commenter thought that the EPA should
eliminate the requirement that a source determine its applicability
status by means of an emissions audit. They felt such a requirement is
unnecessary and contrary to prohibitions in Executive Order 12866 since
major sources, which are subject to part 70 permitting, are already
required to determine their applicable regulatory requirements and
identify them in their permit applications.
In describing the formal means of documenting a facility's major or
area source status as an ``emissions audit'' in the proposal preamble,
the EPA was referring to a calculation of a facility's potential to
emit HAP considering federally enforceable controls. Such calculations
are similar to those already being prepared under many existing Federal
and State control programs. Therefore, the intent of the Agency was in
accord with the thoughts of the commenters. The discussion in the
preamble and the requirements in the final rule are intended to clarify
and simplify compliance with the rule and are not known to be contrary
to provisions of the part 70 permitting requirements. The EPA feels
that guidance on performing HAP emissions inventories is not needed
since the preparation of such inventories is standard practice. The
activities undertaken in response to part 70 requirements are
applicable and may relieve the majority of the burden of fulfilling
this inventory.
Potential to Emit
One commenter felt that the rule was not clear in explaining
whether a facility's major source applicability is determined from
``potential to emit'' (PTE) or actual emissions and asked for
clarification. Several commenters who interpreted the rule to indicate
that PTE should be used expressed disagreement with the EPA, and
believed that basing major source applicability on a source's PTE would
draw into the regulation many more sources than the EPA has
anticipated. They said the EPA should recognize that there are inherent
limits in the operational parameters (throughput, etc.) of gasoline
distribution facilities, and major source determination should be based
on a source's actual emissions or at least a more reasonable gasoline
loading potential. The American Petroleum Institute (API) recommended a
scheme for categorizing facilities based on actual emission rates that
they felt would alleviate the ``potentially drastic consequences'' of
applying the PTE definition. These categories are: I--actual emissions
exceed the major source threshold (10/25 tpy), so the source is subject
to all provisions of the rule; II--actual emissions are greater than 80
percent but less than 100 percent of the major source amounts. The
facility would have to certify its area source status by obtaining a
permit with enforceable limits, submit annual certification of emission
rates, and notify the EPA of any change that could increase HAP
emissions; III--actual emissions are greater than 50 percent but less
than or equal to 80 percent of the major source definition. The
facility would have to submit annual certification and provide
notification of any change; IV--actual emissions are 50 percent or less
of the major source cutoffs. This facility would only have to provide
notification of any changes affecting emissions. Another commenter
suggested that applicability should be based on a combination of the
potential to emit of the vapor recovery system and the actual emissions
of the storage vessel rim seals and fittings using the EPA's current
emission factors.
At proposal, the EPA did not use the term PTE in the preamble
discussion or in the proposed rule. However, the proposed rule and
discussion in the preamble did reference the General Provisions (40 CFR
part 63, subpart A), which includes a definition for PTE. This
definition is as follows:
Potential to emit means the maximum capacity of a stationary
source to emit a pollutant under its physical and operational
design. Any physical or operational limitation on capacity of the
stationary source to emit a pollutant, including air pollution
control equipment and restrictions on hours of operation or the type
or amount of material combusted, stored, or processed, shall be
treated as part of its design if the limitation or the effect it
would have on emissions is federally enforceable.
Terminals and breakout stations have many limitations that affect
emissions and some of these can vary according to gasoline demand.
Industry provided data showing many methods to calculate maximum
capacity, including total tank storage capacity, loading rack pumping
capacity, feeder pipeline pumping rate, etc. Each of these methods of
calculating capacity results in different and conflicting PTE results.
The EPA has decided to provide an approach in the final rule that
provides the facility an opportunity to set some operational and
physical limitations that best fit its own operation only if all the
HAP emitted are from affected gasoline operations. The EPA considered
allowing gasoline terminals and pipeline breakout stations emitting
additional HAP emissions from non-gasoline sources at the plant site to
use this approach. However, the EPA believes covering all situations
and other source categories under this rule would be too complex and
uncertain. Therefore, those sources would have to obtain enforceable
conditions and limitations outside the provisions of this rule.
Under this approach for plant sites emitting HAP only from affected
gasoline operations, the bulk gasoline terminal or pipeline breakout
station facility can establish its potential to emit through a
combination of operational and physical limitations that are otherwise
federally enforceable outside the context of this rule or that are made
enforceable through compliance with parameters included in the
screening equations in this rule. Examples of allowable federally
enforceable limitations and conditions are provided in the definitions
section of the General Provisions (Sec. 63.2). Examples of limitations
at bulk terminals and pipeline stations that are required to meet the
definition of federally enforceable outside the context of this rule
are emission limits on vapor processors that process emissions from
storage vessels and cargo tanks. Recordkeeping and reporting
requirements will be used to monitor compliance with all limitations.
Thus, the final rule allows the facility to limit PTE by complying with
the approved values of the physical or operational parameters contained
in the emission screening equations, such as maximum throughput. This
provides the facility the most flexibility in operations without
overestimating PTE.
The proposed rule required facilities to either use a specific
emission estimation screening equation or prepare an inventory of
emissions to determine their emissions for determination of major or
area source status. The proposal allowed area source facilities to
report their applicability findings and calculations in their initial
notifications to the Agency [required under Sec. 63.9(b)]. After review
and acceptance by the Agency, the facility would have been considered
an area source and would not be subject to the control requirements of
the rule. Changes to the final rule establish certain facility
parameters used in the emission screening equation as new ``physical or
operational limitation[s] on the capacity of the stationary source to
emit a pollutant.'' Upon request, the owner or operator of the bulk
gasoline terminal or pipeline breakout station will be responsible for
demonstrating compliance with the facility's applicability
determination, including all assumptions, limitations, and parameters
used to calculate potential to emit HAP.
To monitor these limitations, certain facilities are required in
the final rule to annually certify that these facility parameters are
not being exceeded. It would be burdensome and unnecessary for all
facilities below the emissions threshold for major sources to provide
detailed reports and records, and annually certify that changes have
not occurred. As suggested in the API comments, only facilities within
50 percent of the emissions threshold for major sources will be
required to submit a detailed report of these calculations and
assumptions used in the calculations in an initial report, and then
provide annual certification that the established facility parameters
are not being exceeded. The remaining facilities will need to retain a
record at the facility of these calculations and notify the
Administrator of the use and results of the emission screening
equation. These records would remain at the facility for inspection by
the Administrator. If the PTE ``limitations'' are exceeded or if the
facility fails to keep records or report as required, the facility will
be in violation of this rule and may in some cases be considered a
major source and be subject to the emission standards of this rule.
The final rule also requires the reports submitted containing those
limitations and certifications to be approved by the Administrator and
made available for public inspection. The notifications and reports
documenting those limitations must be submitted within 1 year of
today's date to the Administrator. The final rule allows facilities to
change these parameters after submittal of the revised calculations and
approval by the Administrator.
If the facility becomes an area (nonmajor) source by complying with
the PTE enforceable limitations and conditions established under this
final rule, then the emission control requirements of this rule would
not apply. Furthermore, for purposes of section 112 of the Act, it
would not be a regulated area source that would be required to have an
operating permit under 40 CFR part 70. In other words, being subject to
the PTE limitations in this rule does not in and of itself make the
facility subject to 40 CFR part 70. However, there may be other reasons
that the stationary source is required to comply with 40 CFR part 70.
The EPA believes the mechanisms provided in this rule for limiting
PTE provide adequate safeguards for this source category. However, the
EPA is still evaluating whether the general approach taken in this rule
will be appropriate for other source categories.
4. Refinery Bulk Terminals
One commenter requested that, for bulk terminals contiguous to
refineries, the EPA clearly define the separation between terminal
storage tanks and refinery storage tanks. These terminals are usually
fed from tanks located within the refinery itself, often thousands of
feet from the terminal. Refinery tanks will be regulated by the NESHAP
for petroleum refineries (proposed at 59 FR 36130, July 15, 1994). The
commenter felt that tanks not located at the terminal itself should be
considered part of the refinery for the purposes of regulation.
Several commenters were of the opinion that the EPA should
distinguish the association and applicability of the gasoline
distribution MACT rule from the refinery MACT rule currently under
development. Many commenters believe that only cargo tank loading racks
and cargo tank leakage should be regulated at terminals that are
``contiguous to'' refineries, and that tankage and equipment leakage
emissions should be regulated under the refinery MACT rule. One
suggested method to distinguish whether facilities are subject to the
refinery rule or the gasoline distribution rule is to consult the
applicable Standard Industrial Classification (SIC) codes already
assigned to these facilities.
Terminals and pipeline facilities contiguous to refineries are of
two types. First, there are terminals and pipeline facilities that are
located within a contiguous area and under common control, but are
managed by the ``marketing'' or ``distribution'' departments, though
they are located on the same property as a refinery. The other type are
terminals and pipeline facilities located among the refinery process
units and storage tanks and managed by the ``refinery'' management
departments. SIC codes are assigned and are currently being used by
these facilities to distinguish between equipment. Industry commenters
expressed a need to retain this separation because they often have
separate management for maintenance, capital improvements, personnel,
and operation of the assigned equipment. This separation would keep the
management of the air pollution control equipment under the same
management structure as the surrounding process equipment. The Agency
agrees with the commenters that maintaining this structure would be
beneficial, because it will increase the management of proper operation
and maintenance of the control equipment, decrease compliance costs,
and improve the reporting and recordkeeping and enforcement of this
rule.
Since a final rule cannot refer to another standard that has not
been promulgated as a final rule, this change is not incorporated into
the final gasoline distribution rule. The Agency, however, plans to
carry out this change by modifying this rule at the promulgation of the
refinery MACT standards. The proposed refinery MACT standards contain
different requirements for equipment leaks and compliance schedules for
storage tanks. The Agency will assess the differences between these two
rules after it considers public comments on the refinery MACT proposal
and develops the final refinery MACT standards. Meanwhile, all
provisions of this gasoline distribution rule will be implemented as
they are being promulgated here, since there are no requirements in
this rule that must be implemented before the scheduled promulgation of
the refinery MACT standards. Independent of the SIC code designation
decision discussed above, the EPA will make a decision in the refinery
MACT rule on the use of emission trading or averaging between the
collocated gasoline distribution and refinery sources.
B. Equipment Leak Requirements
Emission Factors
Several commenters strongly objected to the EPA's use of 1980
refinery data to estimate emissions from equipment (pumps, valves,
etc.) at bulk terminals and pipeline breakout stations. These
commenters were in support of using the new API data gathered at
several bulk terminals. These data indicate that leakage from bulk
terminal and breakout station equipment is very small and that the
refinery emission factors overestimate these emissions greatly. The
commenters pointed out that the EPA's use of the higher factors would
lead to incorrect calculations of applicability status and baseline
emissions.
At proposal, the EPA used the refinery equipment emission factors
in publication AP-42, Section 9.1, Petroleum Refining, to estimate
emissions from equipment components at marketing terminals and pipeline
breakout stations. The API supplied new data which indicated that
corresponding emission factors for marketing terminals and breakout
stations are over 99 percent lower. The EPA has reviewed the data
submitted by API. In May 1994, the EPA released a draft report
containing new correlation equations for marketing facilities using the
API data. The Agency is still reviewing and analyzing the API data to
determine new EPA emission factors. For the purposes of this analysis
and completion of this final rule, API's suggested emission factors are
being used because in our judgement these new factors better reflect
emissions from this source category than the 1980 refinery data. The
EPA intends to issue new EPA emission factors in the near future.
Control Level
Several commenters expressed disagreement with the proposal to
require a leak detection and repair (LDAR) program at bulk terminals
and breakout stations, stating that the emissions from equipment leaks
are much smaller than the EPA had estimated. Consequently, the
commenters considered the EPA's estimated emission reductions due to an
LDAR program to be greatly overstated. As a result, the cost
effectiveness of such a program would be very poor. In lieu of an LDAR
program, many commenters felt that a mandatory visual inspection
program (similar to existing programs at many terminals) would be more
appropriate. The API performed a leak rate survey at bulk terminals,
including both terminals where an LDAR program was in effect and
terminals that were not carrying out a formal LDAR program. The API's
conclusion was that there was no statistically significant difference
in the leak rates found at the two groups of terminals. The commenters
concluded that LDAR programs are more appropriate for refineries, where
the equipment handles fluids at higher temperatures and pressures.
Before proposal of this MACT regulation, the EPA learned that few
existing terminals and pipeline breakout stations (less than 1 percent)
routinely use a portable organic vapor analyzer (OVA) to carry out LDAR
programs on their gasoline handling equipment. As a result, the
``floor'' for control of equipment leaks at existing terminals was
found to be periodic visual inspections (no formal, federally
enforceable inspection program). A monthly LDAR program using an OVA
was determined to be in practice at a few terminals associated with
refineries and therefore was determined to be the floor for equipment
at new terminals and breakout stations. As stated earlier, the EPA in
the proposal analysis used the refinery emission factors in AP-42 to
calculate baseline emissions from equipment leaks at existing
facilities and analyzed LDAR as an ``above the floor'' option. The EPA
found LDAR to be cost effective; however, the Agency noted that there
were industry concerns with the refinery factors and thus did not
select the higher emission reduction alternative (monthly instead of
quarterly LDAR). As discussed above, after reviewing equipment leak
data submitted by API, the EPA agrees that the equipment leak factors
at marketing terminals are much lower than the refinery factors,
resulting in much lower potential emission reductions due to an LDAR
program. As a result of this determination, the cost effectiveness of a
formal instrument LDAR program has been found to be much less favorable
for gasoline marketing facilities.
The new gasoline distribution equipment leak data submitted by API
showed only a slight difference (0.2 percent) between emission factors
at facilities performing periodic LDAR (with an instrument) and
facilities with a periodic visual program. Based on its review of these
data, the EPA agrees with API's assessment that this difference is
statistically insignificant. Therefore, the EPA is in agreement with
the majority of commenters that periodic visual inspection and LDAR
programs achieve essentially equal emission reductions for these
facilities.
Industry submitted survey information that 81 percent of terminal
facilities are implementing some type of periodic visual inspection
program. The survey data did not show the frequency of visual
inspections, but API has stated that current industry periodic visual
programs range in frequency from daily to quarterly. The API suggested
a quarterly program and provided language to make it enforceable and
verifiable through recordkeeping. The program suggested by API
included: (1) A quarterly determination of leaks by visual, audible,
and olfactory inspection of pumps and valves; (2) a log book listing
all of the equipment in gasoline service; (3) note all non-inspected
equipment; (4) if a leak is detected, repair as soon as practical
(considering safety); if the leak cannot be repaired immediately, then
the leak must be repaired or the equipment replaced within 15 calendar
days, unless not practical for reasons stated in the log book or, when
possible, use of the leaking equipment is to be suspended; (5) annual
checks of log book by facility supervisor; and (6) quarterly logs and
records of annual checks retained for 5 years and accessible for
inspection within 3 business days.
The NSPS for bulk gasoline terminals [40 CFR part 60, subpart XX,
Sec. 60.502(j)] requires monthly inspection of loading racks as
follows:
(j) Each calendar month, the vapor collection system, the vapor
processing system, and each loading rack handling gasoline shall be
inspected during loading of gasoline tank trucks for total organic
compounds liquid or vapor leaks. For the purposes of this paragraph,
detection methods incorporating sight, sound, or smell are
acceptable. Each detection of a leak shall be recorded and the
source of the leak repaired within 15 calendar days after it is
detected.
The visual inspection program in the final rule is similar to these
NSPS provisions; however, the provisions have been expanded based on
suggestions of the commenters and certain requirements in existing
Federal LDAR regulations. As in the NSPS, a monthly inspection using
sight, sound, and smell is required. Each detection of a leak is to be
recorded in a log book. Leaks must be repaired as soon as practicable,
but with the first attempt at repair made no later than 5 calendar days
after detection, and repair completed within 15 days after detection.
Delay of repair is allowed upon demonstration to the EPA that timely
repair is not feasible. Full records of each inspection are required,
including for each leak a record of the date of detection, nature of
the leak and detection method, dates of repair attempts and methods
used, and details of any delays of repairs.
The final rule contains a requirement for both new and existing
facilities to perform a visual inspection of equipment on a monthly
basis because it is achieved in practice on the same and similar
equipment under the 40 CFR part 60, subpart XX requirements as
described above and at some facilities that are covered under monthly
LDAR programs in response to 40 CFR part 60, subparts VV and GGG, and
40 CFR part 61, subparts J and V. As noted earlier, the emission
reductions resulting from these visual inspection programs have not
been established, so the emission benefits cannot be quantified other
than to say that periodic inspections ensure low emission levels. The
national annual cost for monthly visual inspections under this final
rule is estimated to be $43,000.
C. Storage Vessel Requirements
Control Level
Several commenters claimed that the discussion in the proposal
concerning the ``floor'' level of control for storage vessels was
inadequate and unclear. The EPA's conclusion was that the NSPS
requirements of 40 CFR part 60, subpart Kb (NSPS subpart Kb)
constituted the floor for storage vessels at existing sources. One
commenter stated that the EPA had not performed an adequate evaluation
to establish the floating roof rim seal requirements of NSPS subpart Kb
as the floor. Several other commenters believed that the EPA had
demonstrated that NSPS subpart Kb's rim seal requirements are the floor
for existing sources, but not the additional NSPS subpart Kb
requirement to control the roof deck fittings. At proposal, the EPA
required gasoline storage vessels at existing facilities to meet all of
the control requirements in NSPS subpart Kb. Subpart Kb specifies
closure devices between the wall of the storage vessel and the edge of
the floating roof (``rim seals''), and the installation of gaskets on
specified lids and other openings in the floating deck (``controlled
fittings''). The EPA also proposed these same requirements as the floor
for new facilities. Subpart Kb is the most recent (1984) new source
performance standard applicable to all new, modified, and reconstructed
volatile organic liquid storage vessels (including gasoline liquid
storage vessels).
Regarding the comments concerning the floor determination for rim
seal requirements for existing sources, the EPA continues to maintain
its previous conclusion that the NSPS subpart Kb rim seal requirements
are the floor for storage vessels at gasoline distribution facilities
as proposed and presented in the proposal notice (February 8, 1994, 59
FR 5868) and further discussed in the promulgation BID. The EPA
believes it did perform a proper evaluation, and the commenter did not
provide any data or information to support a change in the finding that
NSPS subpart Kb rim seals are the floor level of control.
The EPA, however, does agree with the commenters' statements that
the discussion in the proposal preamble did not support the NSPS
subpart Kb fitting control requirements set in 1984 for new tanks as
part of the floor for storage vessels at existing facilities. The EPA
did not have access to any data regarding the number of gasoline
storage vessels that are equipped with controlled fittings. The
commenters also did not provide any data or information on the number
of storage vessels with or without fitting controls for these
subcategories. Information obtained in the tank survey conducted for
the refinery MACT standards was inconclusive regarding the use of
controlled fittings on storage vessels. As a result, the EPA has no
data to support the conclusion that controls on tank fittings are part
of the floor for existing sources. Therefore, the EPA has determined
the existing source MACT floor for fittings as ``uncontrolled.''
The Agency has considered controlled fitting requirements as an
option providing the maximum degree of reduction in HAP emissions
(``above the floor'') as required by the Act. The Administrator is
required under section 112(d) to set emission standards for new and
existing sources of HAP that require the maximum degree of reduction in
emissions of HAP that is achievable, taking into consideration the cost
of achieving the emission reduction, any nonair quality health and
environmental impacts, and energy requirements. New tanks at new or
existing facilities since 1984 are meeting the deck fitting control
requirements in 40 CFR part 60, subpart Kb and, therefore, these
requirements are achievable. Controlling fittings to that level is also
considered the maximum degree of emission reduction.
Emission reductions and costs for controlled fittings were analyzed
on both a per model storage vessel and a nationwide basis using two
typical size and throughput vessels, and different potential HAP
contents in gasoline. Additionally, installation of controlled fittings
on many tanks requires degassing and cleaning of the tanks. Industry
reports that storage vessels are degassed and cleaned at least every 10
years for safety inspections and requested that the Agency require all
retrofits (fittings and rim seals) on storage tanks to occur
simultaneously. Therefore, the new analysis included two options, with
and without degassing and cleaning costs. If fitting controls were
required within 3 years of today's date, the cost impact for this
standard would include the degassing and cleaning costs along with the
cost of controlled fittings if a tank's routine safety inspection would
not have occurred during that 3-year time period. The option of waiting
until the next routine tank degassing and cleaning would avoid the
additional costs of cleaning and degassing as an impact of this
standard since the activity would have occurred anyway. A discussion
and presentation of the model tank analysis of fitting controls are
included in Appendix B of the promulgation BID.
Installing controlled fittings on floating roof tanks, without
degassing and cleaning costs, would result in a cost savings due to the
value of gasoline vapor prevented from evaporating through openings in
the floating roof deck. The capital costs of installing deck fitting
controls on the model tanks, without the cost of degassing and cleaning
of the tanks, ranged in the analysis from $1,200 to $2,800, annualized
costs ranged from a savings to a cost of $340 per year, and the cost
effectiveness ranged from a savings to a cost of $7,500 per megagram of
HAP reduced. When controlled deck fitting installation costs included
degassing and cleaning costs, the capital costs ranged from $21,000 to
$67,000, annualized costs ranged from $4,000 to $14,000 per year, and
the cost effectiveness ranged from $25,000 to $300,000 per megagram of
HAP reduced. Calculation of product price increases under either option
showed them to be insignificant (less than 0.05 cent per gallon). In
conclusion, installing controlled deck fittings is significantly less
costly if it can be done at the next scheduled tank degassing and
cleaning.
The Agency has decided to require installation of controlled deck
fittings on each existing external floating roof storage tank that is
required to be degassed and taken out of service for the purpose of
replacing or upgrading rim seals to meet 40 CFR 60, subpart Kb
requirements. Since these tanks must be degassed and cleaned and have
plant maintenance personnel on site, it is reasonable to require
installation of the fitting controls at the same time. A national
impact analysis was performed on this requirement. Table D-1 in
Appendix D of the promulgation BID presents the results of the national
analysis on storage tanks and other emission sources at bulk terminals
and pipeline breakout stations. Installing fitting controls on external
floating roof tanks is estimated to reduce 66 megagrams per year of HAP
at an annualized cost savings of $93,000.
The cost analyses show that installing controlled fittings when
installing or replacing rim seals on existing external floating roof
tanks involves a small capital cost (approximately $2,000 per tank),
with an annualized cost savings, and insignificant change in gasoline
prices. Given these low costs and the simplicity of these control
measures when tanks are otherwise out of service, the EPA has concluded
that fitting controls are practical and affordable for existing
external floating roof storage tanks. These controls also prevent
pollution and conserve energy by preventing liquid gasoline from
evaporating. Having given full consideration to the directives in the
Act, the Administrator is requiring gasoline storage vessels at
existing facilities to control the deck fittings when replacing or
installing rim seals on external floating roof storage tanks to comply
with the requirements in this final rule. Given the small national HAP
emission reduction, the Agency has decided not to require fitting
controls on existing internal floating roof storage tanks. While the
EPA is not at this time requiring these controls nationally on internal
floating roofs, the EPA encourages industry to consider the
installation of these controls on a case-by-case basis. All new storage
tanks at both new and existing facilities are already required under
NSPS requirements of 40 CFR part 60, subpart Kb to install these same
fitting controls. Those NSPS requirements are cross-referenced and are
therefore part of today's final rule. This level of control for roof
deck fittings for new sources and for existing external floating roof
tanks upgrading to rim seal requirements under this rule, is the same
level as proposed on February 8, 1994. The storage vessel compliance
period is discussed and analyzed in the next section.
While this final rule does not require fitting controls for
existing internal floating roof storage tanks or the existing external
floating roof storage tanks currently meeting the rim seal requirements
in this rule, the Agency believes it is appropriate and recommends the
inspection, repair, and upgrading of gasketing materials on fittings in
the tank roof when any storage tank is taken out of service. It is a
major part of the normal safety and maintenance procedure to inspect,
repair, and upgrade the physical and mechanical condition of all the
tank components. Additionally, requiring fittings to be installed on
all tanks will reduce additional air toxics and volatile organic
compounds, and will upgrade all tanks to the same level of control. An
effective mechanism to get controlled fittings in place on all tanks is
the combination of this rule, the air toxics programs under section
112(l) of the Act, and the national ambient air quality programs for
control of ambient ozone under the Act. The EPA recommends that State
and local air pollution control agencies pursue implementation of
fitting controls on the remaining tanks under those programs.
Compliance Period
Several commenters said that the proposed 3-year compliance period
for storage tanks is unreasonable and is more stringent than the
compliance schedule in other Federal regulations. To install the
required controls, tanks would have to be taken out of service,
cleaned, and degassed. Requiring all storage tanks to comply in a 3-
year period could potentially disrupt the nation's gasoline supply,
causing a gasoline shortage, especially in light of the new
reformulated/oxygenated fuel requirements. One commenter stated that
limited contractor resources could make the schedule logistically
unworkable. Additionally, the cleaning and degassing of a storage tank
creates an air emissions event that in many cases will exceed the
emission reductions resulting from the new controls (e.g., the retrofit
of an internal floating roof tank already meeting 40 CFR part 60,
subpart Ka rim seal requirements). One commenter stated that the EPA
must perform a cost effectiveness analysis to support a 3-year
compliance date. All of the commenters suggested that the EPA relax the
compliance schedule and allow storage tank owners and operators to
comply at the next scheduled tank inspection or within 10 years,
whichever comes first. One of the commenters felt that a 10-year period
is an integral part of the floor for existing sources. This commenter
recommended that, should the EPA not allow up to 10 years for
compliance for all tanks currently equipped with floating roofs, at a
minimum internal floating roof tanks currently meeting NSPS subpart Ka
requirements should be provided a compliance period up to 10 years, or
the next regular inspection cycle, whichever occurs first.
Section 112(i)(3) of the Act requires the Administrator to
establish a compliance date which shall provide for compliance as
expeditiously as practicable, but in no event later than 3 years after
the effective date (promulgation) of the standards. In addition, the
Administrator (or a State with a program approved under title V) may
issue a permit which grants up to a 1-year extension to comply with the
standards if an additional period is necessary for installation of
controls. However, some commenters suggest that taking a tank out of
service before its normal cleaning and inspection schedule to comply
with the regulation may generate more emissions than the added controls
would reduce or control in the 3-year period.
To determine whether any tanks should be allowed an extension of
the compliance time to achieve the maximum degree of reduction in
emissions of HAP, the EPA compared the emission reductions achieved by
the controls (i.e., rim seals and fittings controls) to the emissions
generated from degassing and cleaning of fixed-roof and internal and
external floating roof tanks for various tank diameters and gasoline
turnover rates. The results of this analysis showed that additional
degassing and cleaning emissions do not exceed the emission reductions
from tanks complying with this final rule within the required 3-year
compliance period. The analysis did show net emissions increases for
some very large tanks either installing secondary seals without
installing fitting controls, or installing fitting controls alone.
However, these final standards require a facility to install fitting
controls when installing secondary rim seals, and no tanks are required
to install fitting controls alone. A complete discussion of this
analysis of emissions generated from tank cleaning and degassing is
presented in Appendix B of the promulgation BID.
D. Cargo Tank Requirements
Emission Factors
Several commenters stated that the EPA's assumption at proposal
that tank trucks that have passed the EPA Method 27 annual vapor
tightness test leak 10 percent of their emissions during controlled
loading is outdated and inaccurate. Consequently, the baseline
emissions calculated for tank trucks are grossly overstated. New data
suggest that very few tank trucks leak due to today's better
construction standards and the test requirements in effect under
current Federal and State rules. One commenter provided calculations
indicating that, under the proposed pressure decay standard (which is
the same as the 40 CFR part 60, subpart XX NSPS requirement), a typical
controlled tank truck would have a leakage emission factor for loading
of 5.6 mg/liter (at the allowable maximum of 18 in. H<INF>2O
backpressure). Another commenter estimated, on the basis of test
failure rate data from the Bay Area Air Quality Management District
(BAAQMD) and several oil companies, that the overall average leak rate
is 0.88 percent of the total volume of vapors displaced during the
loading of tank trucks connected to a vapor recovery system.
The EPA's estimate of 10 percent vapor leakage from emission
sources in tank trucks while loading at controlled loading racks was
based on data collected in 1978 on 27 tank trucks in California. These
tank trucks were under a State requirement to be certified annually in
a vapor tightness test, and time periods ranging from 4 days to a full
year had elapsed since the last certification test for these trucks.
The volume losses among the trucks varied from 0.1 to 35.8 percent,
with the average leakage being about 10 percent. The data from these
tests were further described, and the 10 percent figure derived, in the
BID for the proposed NSPS for bulk gasoline terminals (docket item IIA
-14).
The commenter who supplied the 0.88 percent overall leakage
estimate relied upon vapor volume loss data for individual tank trucks
reported in the 1978 study, and combined these data with test failure
rate data from the BAAQMD (pressure test data) and from several oil
companies (combustible gas detector results gathered during loading
rack performance tests). Based on an assumption that a leak definition
of 10,000 ppm is equivalent to a 1 percent loss of vapors through
leakage, the commenter determined that the average leak rate for tanks
with leakage rates over 1 percent (``failing'' tanks) was 12.1 percent,
while the average leak rate for the remaining, ``passing'' tanks was
0.5 percent. On the basis of the failure rate data, the overall failure
rate during 1989 to 1994 was found to be 3.3 percent. Combining the
average leak rate figures with these failure prevalence data, the
commenter arrived at the overall leak rate for all tank trucks of 0.88
percent.
The EPA recognizes and agrees with the commenter that the available
data indicate that overall vapor leakage rates from tank trucks subject
to a regular test and repair program using the pressure decay procedure
have been reduced over the past 16 years. However, the use of
concentration data to estimate a volume leakage rate, as the commenter
has done, is uncertain. In addition, neither the EPA nor industry have
access to current data for several areas throughout the country that
would allow a national average calculation of this volume leakage to be
made. Therefore, any numerical result derived from the existing data
would be at best a broad estimate, which would not account for the full
range of truck ages, ownership scenarios, and local control programs.
In spite of these limitations, the EPA has made an estimate which
it feels more closely reflects actual overall emissions under a vaportight
cargo tank program than the emission factor used for the
proposal. The Agency's new emission factor, 0.8 percent of the total
vapors displaced or 8 mg of VOC/liter, is based on the use of a volume
loss equation found in Appendix C of the tank truck CTG (EPA-450/2-78-
combined with the test failure rate data submitted by the
commenter and measured leakage from trucks that failed the test. This
new emission factor represents the emissions after control to the level
of today's final standards as discussed in the following sections. The
promulgation BID, Appendix A presents more details on the calculation
of this emission factor.
Control Level
a. Vacuum assist vapor collection. Many commenters expressed
opposition to the proposal to require use of ``vacuum assist''
technology at new bulk terminal loading racks. Most of the commenters
felt that annual vapor tightness testing is adequate to control tank
truck leakage emissions. Some commenters expressed safety concerns;
e.g., the potential for fires and tank truck implosion. One of them
said that internal tank vacuums can (and already do) damage the
internal compartment heads of tank trucks by reversing those heads and
weakening the tank's outer shell, which compromises product retention
capability. Several do not believe that vacuum assist technology has
been demonstrated as ``achievable in practice.'' The technology has
been used in only one State (Texas) and has not been tested under
various climatic conditions, such as combined low temperatures and high
humidity levels. Others believe that the complexity of the loading
system would increase. Also, due to rapid fluctuations in gasoline flow
rates and the requirement to maintain a vacuum at all times during
loading, nuisance shutdowns of the loading operation could be a
problem. One commenter said that such a system may adversely affect the
efficiency of the vapor control device because air can leak into the
vapor collection system and dilute the inlet VOC concentration. Another
commenter felt that volatilization of fuel in the cargo tank would be
increased due to the vacuum, sending more vapors to the control device.
This would require a larger device which may have greater emissions,
and more solid waste impact for the case of a carbon system. One
commenter said that vacuum assist systems will increase electrical
power consumption 15 to 400 percent depending on the type of emission
control device used. Others said that vacuum assist is unnecessary,
because tank trucks do not leak enough during loading to justify vacuum
assist as a means of reducing the losses. Recent API data show that
tank truck leakage has been significantly reduced since the EPA study
performed in 1978. Three commenters said that the system addresses
losses from the tank truck only while loading at the terminal and not
while in transit or while operating at bulk plants and service
stations. Other commenters said that vacuum assist is very expensive
and not cost effective.
The vacuum assist system was proposed for new source bulk terminals
to control HAP emissions due to vapor leaks from cargo tanks during
gasoline loading operations. This system creates a negative pressure in
the vapor collection system during loading to ensure that vapors will
not be forced out into the air through any leakage points. The proposal
rationale was based on the following information. Vacuum assist systems
are in use at a few bulk gasoline terminals (in addition to the annual
vapor tightness test for truck tanks) in Texas, so it meets the Act
requirement to consider the best controlled similar source in
establishing the floor level of control for new terminals. Since less
than 1 percent of terminals use this vacuum assist system, it is not
considered the floor for cargo tank leakage at existing terminals.
Annual vapor tightness testing of cargo tanks was considered at
proposal to be the floor for existing terminals (this floor
determination has been modified on the basis of public comments; see 59
FR 42788, August 19, 1994). Based on field tests in the late 1970's, an
annual vapor tightness testing program was estimated to reduce the
leakage rate from baseline levels at 30 percent leakage to about 10
percent leakage. The vacuum assist system was estimated to reduce the
10 percent leakage rate under the annual vapor tightness test program
by nearly 100 percent.
Industry sources had expressed concerns before proposal regarding
the operational reliability of a vacuum assist system, especially under
extreme cold weather conditions. Those commenters also believed that
the system could present a safety hazard if excess negative pressures
were developed within a tank truck fuel compartment. To the Agency's
knowledge, the systems in operation have not experienced any
significant problems, and one of the systems has been operating for
over 3 years. These systems contain safety pressure relief devices in
combination with the pressure-vacuum vents already installed on each
tank truck compartment. However, safety concerns are important to the
Agency. The Agency specifically requested comment at proposal,
including technical documentation and data where available, on the
reliability, effectiveness, safety aspects, and any other issue
concerning vacuum producing equipment for bulk terminal vapor
collection systems. No technical documentation or data on installed
systems was provided during the comment period.
As discussed above in Section III.D.1, the leakage emission factor
for controlled cargo tanks under an annual vapor tightness program was
adjusted to reflect current data on the frequency with which cargo
tanks pass the test on the first attempt. Emissions lost from cargo
tanks under test programs with a pressure decay limit of 3 in. H<INF>2O
are now estimated to be 1.3 percent of total vapor displaced during
loading operations (just under 99 percent collection efficiency). In
California, where an annual pressure decay limit of 1 inch of water is
in effect, the emission losses during loading are estimated at 0.8
percent (slightly over 99 percent collection). The corresponding HAP
emission factors are 0.4 and 1.3 mg/liter of HAP for normal and
oxygenated gasolines, respectively. At proposal, the leakage emission
rate was estimated to be a 10 percent loss (90 percent collection
efficiency). Thus, while vacuum assist systems were previously thought
to have the potential to capture an additional 10 percent of the
loading emissions, they now appear to have the potential to capture
about 1 percent.
The EPA shares commenters' concerns that the emission control
achieved with the vacuum assist system is uncertain. The Agency's
uncertainty centers on the system's effectiveness in accurately
maintaining a slight vacuum to collect a small leak (1 percent of the
volume displaced to the collection system) while handling the
variability of flows and pressures and limiting the ingestion of air
into the system to a degree where it does not affect the control
effectiveness of the processor. The vapor volume collected by the
system and internal pressures within the vapor collection system vary
widely throughout the day. Each cargo tank loading and displacing
vapors influences the pressures and flows in the system. Terminals
operate on demand, just like gasoline service stations. The number of
tanks loading at any given time varies from none, to a few, to 10 or
more tanks. Additionally, vapor processor control efficiency may be
adversely influenced by increased amounts of air sent to the control
system. A vacuum assist system draws additional air into the system.
Even small malfunctions in the system would be likely to increase
emissions above the 1 percent control target. Finally, the Agency
agrees that it lacks sufficient information to determine whether
conditions outside of Texas may affect the control performance of
vacuum assist methods.
The proposal of vacuum assist was based on the minimum baseline
(floor) at which standards may be set. Under section 112(d)(3) of the
Act, the floor for new sources
shall not be less stringent than the emission control that is
achieved in practice by the best controlled similar source, as
determined by the Administrator.
The Administrator has determined that emission control is not being
achieved in practice given the technical uncertainties about achieving
emission reduction from this source as discussed in the previous
paragraph. Consequently, the proposed vacuum assist requirement for new
bulk terminals has been deleted from the final rule.
b. Vapor tightness standards. Two commenters recommended during the
proposal's comment period that the EPA implement the cargo tank vapor
tightness program in effect within the State of California since 1977.
The California standard requires annual certification that cargo tanks
meet 5-minute pressure and vacuum decay standards of 1 inch of water
column (in. H<INF>2O). Based on a BAAQMD survey of 200 tank truck
owners which quantified actual pressure change values, California is
proposing to lower this annual standard to 0.5 in. H<INF>2O. In
addition, the same commenters recommended that the EPA apply the
California year-round standard of 2.5 in. H<INF>2O pressure loss in 5
minutes. The EPA published a supplemental Federal Register notice (59
FR 42788, August 19, 1994) and opened a comment period for
consideration of the existing California standards as the level of
control for new and existing sources in the final MACT rule. The
following comments were received on the floor determination and on the
level of control that is appropriate for controlling cargo tank
leakage. The promulgation BID summarizes additional comments and
responses to comments received on the proposal and supplemental notice.
Five commenters felt that the existing California standards should
be specified for cargo tanks at new sources, but would be inappropriate
for existing sources. These commenters based their opinion on the
conclusion that the EPA had inappropriately based its floor
determination on California's gasoline throughput, or number of tank
trucks operating in the State. They felt that, since the legal
responsibility for compliance would be on the terminal owner or
operator, the basis should be the number of terminals in California.
One commenter said that this figure is 71, out of a total of 1,125
terminals nationwide (6.3 percent). Since this value is less than the
required 12 percent, applying this control level to existing sources
would be an ``above the floor'' option. Thus, a cost effectiveness
analysis should be provided to justify the California standards as the
existing source floor. Another commenter stated that the California
Highway Patrol, which monitors California's tank testing program, does
not include vapor tightness testing in its 44-point program for
inspecting out-of-State cargo tanks. The commenter felt that this issue
could impact the foundation upon which the EPA had reopened the
proposal action. Two commenters favored incorporation of the California
standards for both new and existing sources.
Several commenters responded to the EPA's request for comments on
whether the level of control for cargo tanks at new and existing
facilities should be based on the existing or the proposed California
standards. Commenters were unanimous in asserting that only the
existing, and not the proposed, California standards should be
considered. Two of the commenters felt that BAAQMD's survey of 200 tank
truck owners was not sufficiently representative to indicate that the
more stringent proposed standards should be applied. Another commenter
said the proposed requirements should not be adopted because: (1) the
testing in the survey has not been properly peer reviewed, (2) the
proposal has yet to be adopted by the California Air Resources Board
(ARB), and (3) there is no conclusive demonstration of any significant
emissions difference between the current and proposed standards. Two
other commenters echoed that there is no basis for considering the more
stringent standards because the effect on tank truck emissions is
unknown. Finally, one commenter requested that the EPA consider the
proposed California standards for new and existing facilities, feeling
that this would standardize regulations nationwide and result in lower
costs for equipment and remove some burden from the California ARB.
The California 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 and are checked by
the California air pollution control districts. In summary, they
include three major standards: an annual certification, 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 in.
H<INF>2O and to 6 in. H<INF>2O, respectively. In 5 minutes the
allowable pressure change may be no more than the values shown in Table
Further details on the performance requirements and test procedures
used in the California program were discussed at 59 FR 42788. The EPA's
Control Techniques Guideline (CTG) document and NSPS, 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 75 mm of water column (3 in. H<INF>2O) is
allowed for all tank trucks under the NSPS, the CTG, and the proposal.
Table 1.--Allowable Cargo Tank Test Pressure or Vacuum Change
Annual
certification- Allowable
allowable pressure
in 5 minutes, time, mm H<INF>2O
mm H<INF>2O (in. (in. H<INF>2O)
H<INF>2O)
40 CFR citation OMB control No.
*****
National Emission Standards for Hazardous Air
Pollutants for Source Categories....................
*****
*****
Annual
certification- Allowable
allowable pressure
pressure or change (<greek-
<greek-D>v) in time, mm H<INF>2O
5 minutes, mm (in. H<INF>2O)
H<INF>2O (in. H<INF>2O)
Interval
pressure
Time interval change, mm
H<INF>2O (in.
H<INF>2O)
Table 1 to Subpart R--General Provisions Applicability to Subpart R
Applies to
Reference subpart R Comment
63.1(a)(5)............................................. No Section reserved
63.1(a)(9)............................................. No Section reserved
Sec. 63.420
recordkeeping for some large area
sources in Sec. 63.428
subpart R
63.1(c)(3)............................................. No Section reserved
63.1(d)................................................ No Section reserved
63.4(a)(4)............................................. No Section reserved
63.5(b)(2)............................................. No Section reserved
63.5(c)................................................ No Section reserved
63.6(b)(6)............................................. No Section reserved
63.6(c)(3)-(c)(4)...................................... No Sections reserved
63.6(d)................................................ No Section reserved
63.6(i)(15)............................................ No Section reserved
63.8(a)(3)............................................. No Section reserved
notification requirement
63.9(h)(4)............................................. No Section reserved
63.10(c)(2)-(c)(4)..................................... No Sections reserved
63.10(c)(9)............................................ No Section reserved
Applies
to
Reference subpart Comment
R
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