[Federal Register Volume 79, Number 127 (Wednesday, July 2, 2014)]
[Proposed Rules]
[Pages 37850-37895]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2014-13490]
[[Page 37849]]
Vol. 79
Wednesday,
No. 127
July 2, 2014
Part II
Environmental Protection Agency
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40 CFR Part 63
National Emission Standards for Hazardous Air Pollutants: Off-Site
Waste and Recovery Operations; Proposed Rule
Federal Register / Vol. 79 , No. 127 / Wednesday, July 2, 2014 /
Proposed Rules
[[Page 37850]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 63
[EPA-HQ-OAR-2012-0360; FRL-9911-93-0A]
RIN 2060-AR47
National Emission Standards for Hazardous Air Pollutants: Off-
Site Waste and Recovery Operations
AGENCY: Environmental Protection Agency.
ACTION: Proposed rule.
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SUMMARY: The Environmental Protection Agency (EPA) is proposing
amendments to the national emission standards for hazardous air
pollutants (NESHAP) for off-site waste and recovery operations (OSWRO)
to address the results of the residual risk and technology review (RTR)
conducted under the Clean Air Act (CAA). In light of our residual risk
and technology review, we are proposing to amend the requirements for
leak detection and repair and the requirements for certain tanks. In
addition, the EPA is proposing amendments to revise regulatory
provisions pertaining to emissions during periods of startup, shutdown
and malfunction; add requirements for electronic reporting of
performance test results; revise the routine maintenance provisions;
clarify provisions pertaining to open-ended valves and lines; add
monitoring requirements for pressure relief devices; clarify provisions
for some performance test methods and procedures; and make several
minor clarifications and corrections.
DATES:
Comments. Comments must be received on or before August 18, 2014. A
copy of comments on the information collection provisions should be
submitted to the Office of Management and Budget (OMB) on or before
August 1, 2014.
Public Hearing. We do not plan to conduct a public hearing unless
requested. If requested, we will hold a public hearing on July 17,
2014. To request a hearing, please contact the person listed in the
following FOR FURTHER INFORMATION CONTACT section by July 14, 2014.
ADDRESSES:
Comments. Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2012-0360, by one of the following methods:
Federal eRulemaking Portal: http://www.regulations.gov.
Follow the online instructions for submitting comments.
Email: [email protected]. Include Docket ID No. EPA-
HQ-OAR-2012-0360 in the subject line of the message.
Fax: (202) 566-9744, Attention Docket ID No. EPA-HQ-OAR-
2012-0360.
Mail: Environmental Protection Agency, EPA Docket Center
(EPA/DC), Mail Code 28221T, Attention Docket ID No. EPA-HQ-OAR-2012-
0360, 1200 Pennsylvania Avenue NW., Washington, DC 20460. Please
include a total of two copies. In addition, please mail a copy of your
comments on the information collection provisions to the Office of
Information and Regulatory Affairs, Office of Management and Budget
(OMB), Attn: Desk Officer for EPA, 725 17th Street NW., Washington, DC
20503.
Hand/Courier Delivery: EPA Docket Center, Room 3334, EPA
WJC West Building, 1301 Constitution Avenue NW., Washington, DC 20004,
Attention Docket ID No. EPA-HQ-OAR-2012-0360. Such deliveries are only
accepted during the Docket's normal hours of operation, and special
arrangements should be made for deliveries of boxed information.
Instructions. Direct your comments to Docket ID No. EPA-HQ-OAR-
2012-0360. The EPA's policy is that all comments received will be
included in the public docket without change and may be made available
online at http://www.regulations.gov, including any personal
information provided, unless the comment includes information claimed
to be confidential business information (CBI) or other information
whose disclosure is restricted by statute. Do not submit information
that you consider to be CBI or otherwise protected through http://www.regulations.gov or email. The http://www.regulations.gov Web site
is an ``anonymous access'' system, which means the EPA will not know
your identity or contact information unless you provide it in the body
of your comment. If you send an email comment directly to the EPA
without going through http://www.regulations.gov, your email address
will be automatically captured and included as part of the comment that
is placed in the public docket and made available on the Internet. If
you submit an electronic comment, the EPA recommends that you include
your name and other contact information in the body of your comment and
with any disk or CD-ROM you submit. If the EPA cannot read your comment
due to technical difficulties and cannot contact you for clarification,
the EPA may not be able to consider your comment. Electronic files
should not include special characters or any form of encryption and be
free of any defects or viruses. For additional information about the
EPA's public docket, visit the EPA Docket Center homepage at: http://www.epa.gov/dockets.
Docket. The EPA has established a docket for this proposed rule
under Docket ID No. EPA-HQ-OAR-2012-0360. All documents in the docket
are listed in the regulations.gov index. Although listed in the index,
some information is not publicly available, e.g., CBI or other
information whose disclosure is restricted by statute. Certain other
material, such as copyrighted material, is not placed on the Internet
and will be publicly available only in hard copy. Publicly available
docket materials are available either electronically in regulations.gov
or in hard copy at the EPA Docket Center, WJC West Building, Room 3334,
1301 Constitution Ave., NW., Washington, DC. The Public Reading Room is
open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding
legal holidays. The telephone number for the Public Reading Room is
(202) 566-1744, and the telephone number for the EPA Docket Center is
(202) 566-1742.
Public Hearing. If requested, we will hold a public hearing
concerning this proposed rule on July 17, 2014 in the Research Triangle
Park, North Carolina area. The EPA will provide further information
about the hearing at the following Web site, http://www.epa.gov/ttn/oarpg/t3main.html, if a hearing is requested. Persons interested in
presenting oral testimony at the hearing should contact Ms. Virginia
Hunt, Sector Policies and Programs Division (E143-01), Office of Air
Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC 27711, telephone number (919) 541-0832, by
July 17, 2014. If no one requests to speak at the public hearing by
July 14, 2014, then a public hearing will not be held, and a
notification of such will be posted on http://www.epa.gov/ttn/oarpg/t3main.html.
FOR FURTHER INFORMATION CONTACT: For questions about this proposed
action, contact Ms. Paula Hirtz, Sector Policies and Programs Division
(E143-01), Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle Park, NC 27711;
telephone number: (919) 541-2618; fax number: (919) 541-0246; and email
address: [email protected]. For specific information regarding the
risk modeling methodology, contact Ms. Darcie Smith, Health and
Environmental Impacts Division (C504-06), Office of Air Quality
Planning and
[[Page 37851]]
Standards, U.S. Environmental Protection Agency, Research Triangle
Park, NC 27711; telephone number (919) 541-2076; fax number: (919) 541-
0840; and email address: [email protected]. For information about
the applicability of the National Emission Standards for Hazardous Air
Pollutants (NESHAP) to a particular entity, contact Ms. Marcia Mia, EPA
Office of Enforcement and Compliance Assurance, telephone number (202)
564-7042; email address: [email protected].
SUPPLEMENTARY INFORMATION:
Preamble Acronyms and Abbreviations
We use multiple acronyms and terms in this preamble. While this
list may not be exhaustive, to ease the reading of this preamble and
for reference purposes, the EPA defines the following terms and
acronyms here:
AEGL--acute exposure guideline levels
AERMOD--air dispersion model used by the HEM-3 model
CAA--Clean Air Act
CalEPA--California EPA
CBI--Confidential Business Information
CDX--Central Data Exchange
CEDRI--Compliance and Emissions Data Reporting Interface
CFR--Code of Federal Regulations
EPA--Environmental Protection Agency
ERPG--Emergency Response Planning Guidelines
ERT--Electronic Reporting Tool
FR--Federal Register
HAP--hazardous air pollutants
HCl--hydrochloric acid
HEM-3--Human Exposure Mdel, Version 1.1.0
HF--hydrogen fluoride
HI--hazard index
HON--Hazardous Organic NESHAP
HQ--hazard quotient
ICR--Information Collection Request
IRIS--Integrated Risk Information System
km--kilometer
kPa--kilopascal
LDAR--leak detection and repair
LOAEL--lowest-observed-adverse-effect level
MACT--maximum achievable control technology
m\3\--cubic meter
mg/kg-day--milligrams per kilogram per day
mg/m\3\--milligrams per cubic meter
MIR--maximum individual risk
NAAQS--National Ambient Air Quality Standards
NAICS--North American Industry Classification System
NAS--National Academy of Sciences
NATA--National Air Toxics Assessment
NESHAP--National Emissions Standards for Hazardous Air Pollutants
NOAA--National Oceanic and Atmospheric Organization
NOAEL--no-observed-adverse-effect level
NRC--National Research Council
NTTAA--National Technology Transfer and Advancement Act
OAQPS--Office of Air Quality Planning and Standards
OMB--Office of Management and Budget
OSWRO--off-site waste and recovery operations
PB-HAP--hazardous air pollutants known to be persistent and bio-
accumulative in the environment
PEL--probable effect levels
POM--polycyclic organic matter
ppm--parts per million
PRD-- pressure relief device
PTE--permanent total enclosure
RCO--recuperative thermal oxidizer
RCRA--Resource Conservation and Recovery Act
REL--reference exposure level
RFA--Regulatory Flexibility Act
RfC--reference concentration
RfD--reference dose
RIA--Regulatory Impact Analysis
RTR--residual risk and technology review
SAB--Science Advisory Board
SBA--Small Business Administration
SCC--source classification code
S/L/Ts--State, local and tribal air pollution control agencies
SOP--standard operating procedures
SSM--startup, shutdown and malfunction
TEQ--toxicity equivalence factor
TOC--total organic compound
TOSHI--target organ-specific hazard index
tpy--tons per year
TRIM.FaTE--Total Risk Integrated Methodology.Fate, Transport and
Ecological Exposure model
TSDF--Solid Waste Treatment, Storage and Disposal Facility
TTN--Technology Transfer Network
UF--uncertainty factor
UMRA--Unfunded Mandates Reform Act
URE--unit risk estimate
VCS--voluntary consensus standards
Organization of this Document. The information in this preamble is
organized as follows:
I. General Information
A. Does this action apply to me?
B. Where can I get a copy of this document and other related
information?
C. What should I consider as I prepare my comments for the EPA?
II. Background
A. What is the statutory authority for this action?
B. What is this source category and how does the current NESHAP
regulate its HAP emissions?
C. What data collection activities were conducted to support
this action?
III. Analytical Procedures
A. How did we estimate post-MACT risks posed by the source
category?
B. How did we consider the risk results in making decisions for
this proposal?
C. How did we perform the technology review?
IV. Analytical Results and Proposed Decisions
A. What are the results of the risk assessment and analyses?
B. What are our proposed decisions regarding risk acceptability,
ample margin of safety and adverse environmental effects?
C. What are the results of the technology review and our
proposed decisions?
D. What other actions are we proposing?
E. What compliance dates are we proposing?
V. Summary of Cost, Environmental, and Economic Impacts
A. What are the affected sources?
B. What are the air quality impacts?
C. What are the cost impacts?
D. What are the economic impacts?
E. What are the benefits?
VI. Request for Comments
VII. Submitting Data Corrections
VIII. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory Review
B. Paperwork Reduction Act
C. Regulatory Flexibility Act
D. Unfunded Mandates Reform Act
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
G. Executive Order 13045: Protection of Children From
Environmental Health Risks and Safety Risks
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
I. National Technology Transfer and Advancement Act
J. Executive Order 12898: Federal Actions to Address
Environmental Justice in Minority Populations and Low-Income
Populations
A red-line version of the regulatory language that incorporates the
proposed changes in this action is available in the docket for this
action (Docket ID No. EPA-HQ-OAR-2012-0360).
I. General Information
A. Does this action apply to me?
Table 1 of this preamble lists the NESHAP and associated regulated
industrial source category that is the subject of this proposal. Table
1 is not intended to be exhaustive but rather to provide a guide for
readers regarding the entities that this proposed action is likely to
affect. The proposed standards, once promulgated, will be directly
applicable to the affected sources. The Off-site Waste and Recovery
Operations source category was initially titled the ``Solid Waste
Treatment, Storage, and Disposal Facilities (TSDF)'' source category,
which included commercial facilities that treat, store or dispose of
any solid waste received from off-site, as well as commercial
facilities that recycle, recover and re-refine wastes received from
off-site.\1\ On October 13,
[[Page 37852]]
1994 (59 FR 51913), the EPA explained that the source category was
intended to represent those off-site waste and recovery operations that
are not specifically listed as a separate distinct NESHAP source
category such as hazardous waste incineration or municipal solid waste
landfills and changed the title of the Solid Waste TSDF source category
to ``Off-Site Waste and Recovery Operations'' to avoid confusion, to
better distinguish this source category from other source categories,
and to emphasize that this source category addresses only activities
that manage wastes received from off-site.
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\1\ See Initial List of Categories of Sources Under Section
112(c)(1) of the Clean Air Act Amendments of 1990 (57 FR 31576, July
16, 1992); U.S. EPA. Documentation for Developing the Initial Source
Category List (EPA-450/3-91-030; July 1992).
Table 1--NESHAP and Industrial Source Categories Affected By This Proposed Action
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Source category NESHAP Examples of regulated entities
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Off-Site Waste and Recovery Operations. Off-Site Waste and Businesses or government agencies that
Recovery Operations. operate any of the following: Hazardous
waste TSDF; Resource Conservation and
Recovery Act (RCRA) exempt hazardous
wastewater treatment facilities;
nonhazardous wastewater treatment
facilities other than publicly-owned
treatment works; used solvent recovery
plants; RCRA exempt hazardous waste
recycling operations; used oil re-
refineries.
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This table is not intended to be exhaustive, but rather is meant to
provide a guide for readers regarding entities likely to be affected by
this action. If you have any questions regarding the applicability of
this action to a particular entity, consult either the air permitting
authority for the entity or your EPA regional representative, as listed
in 40 CFR 63.13 (General Provisions).
B. Where can I get a copy of this document and other related
information?
In addition to being available in the docket, an electronic copy of
this action is available on the Internet through the EPA's Technology
Transfer Network (TTN) Web site, a forum for information and technology
exchange in various areas of air pollution control. Following signature
by the EPA Administrator, the EPA will post a copy of this proposed
action on the TTN's policy and guidance page for newly proposed or
promulgated rules at: http://www.epa.gov/ttn/oarpg/t3pfpr.html.
Following publication in the Federal Register, the EPA will post the
Federal Register version of the proposal and key technical documents on
the project Web site: http://www.epa.gov/ttn/atw/offwaste/oswropg.html.
Information on the overall RTR program is available at the following
Web site: http://www.epa.gov/ttn/atw/rrisk/rtrpg.html.
C. What should I consider as I prepare my comments for the EPA?
Submitting CBI. Do not submit information containing CBI to the EPA
through http://www.regulations.gov or email. Clearly mark the part or
all of the information that you claim to be CBI. For CBI information on
a disk or CD-ROM that you mail to the EPA, mark the outside of the disk
or CD-ROM as CBI and then identify electronically within the disk or
CD-ROM the specific information that is claimed as CBI. In addition to
one complete version of the comments that includes information claimed
as CBI, you must submit a copy of the comments that does not contain
the information claimed as CBI for inclusion in the public docket. If
you submit a CD-ROM or disk that does not contain CBI, mark the outside
of the disk or CD-ROM clearly that it does not contain CBI. Information
not marked as CBI will be included in the public docket and the EPA's
electronic public docket without prior notice. Information marked as
CBI will not be disclosed except in accordance with procedures set
forth in 40 Code of Federal Regulations (CFR) part 2. Send or deliver
information identified as CBI only to the following address: Roberto
Morales, OAQPS Document Control Officer (C404-02), OAQPS, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711, Attention Docket ID No. EPA-HQ-OAR-2012-0360.
II. Background
A. What is the statutory authority for this action?
Section 112 of the CAA establishes a two-stage regulatory process
to address emissions of hazardous air pollutants (HAPs) from stationary
sources. In the first stage, after the EPA has identified categories of
sources emitting one or more of the HAP listed in CAA section 112(b),
CAA section 112(d) requires us to promulgate technology-based NESHAP
for those sources. ``Major sources'' are those that emit or have the
potential to emit 10 tons per year (tpy) or more of a single HAP or 25
tpy or more of any combination of HAPs. For major sources, the
technology-based NESHAP must reflect the maximum degree of emission
reductions of HAPs achievable (after considering cost, energy
requirements and non-air quality health and environmental impacts) and
are commonly referred to as maximum achievable control technology
(MACT) standards.
MACT standards must reflect the maximum degree of emissions
reduction achievable through the application of measures, processes,
methods, systems or techniques, including, but not limited to, measures
that (1) reduce the volume of or eliminate pollutants through process
changes, substitution of materials or other modifications; (2) enclose
systems or processes to eliminate emissions; (3) capture or treat
pollutants when released from a process, stack, storage or fugitive
emissions point; (4) are design, equipment, work practice or
operational standards (including requirements for operator training or
certification); or (5) are a combination of the above. CAA section
112(d)(2)(A)-(E). The MACT standards may take the form of design,
equipment, work practice or operational standards where the EPA first
determines either that (1) a pollutant cannot be emitted through a
conveyance designed and constructed to emit or capture the pollutant,
or that any requirement for, or use of, such a conveyance would be
inconsistent with law; or (2) the application of measurement
methodology to a particular class of sources is not practicable due to
technological and economic limitations. CAA section 112(h)(1)-(2).
The MACT ``floor'' is the minimum control level allowed for MACT
standards promulgated under CAA section 112(d)(3) and may not be based
on cost considerations. For new sources, the MACT floor cannot be less
stringent than the emissions control that is achieved in practice by
the best-
[[Page 37853]]
controlled similar source. The MACT floor for existing sources can be
less stringent than floors for new sources but not less stringent than
the average emissions limitation achieved by the best-performing 12
percent of existing sources in the category or subcategory (or the
best-performing five sources for categories or subcategories with fewer
than 30 sources). In developing MACT standards, the EPA must also
consider control options that are more stringent than the floor. We may
establish standards more stringent than the floor based on
considerations of the cost of achieving the emission reductions, any
non-air quality health and environmental impacts and energy
requirements.
The EPA is required to review these technology-based standards and
revise them ``as necessary (taking into account developments in
practices, processes, and control technologies)'' no less frequently
than every eight years. CAA section 112(d)(6). In conducting this
review, the EPA is not required to recalculate the MACT floor. Natural
Resources Defense Council (NRDC) v. EPA, 529 F.3d 1077, 1084 (D.C. Cir.
2008). Association of Battery Recyclers, Inc. v. EPA, 716 F.3d 667
(D.C. Cir. 2013).
The second stage in standard-setting focuses on reducing any
remaining (i.e., ``residual'') risk according to CAA section 112(f).
Section 112(f)(1) required EPA to prepare a report to Congress
discussing (among other things) methods of calculating the risks posed
(or potentially posed) by sources after implementation of the MACT
standards, the public health significance of those risks and the EPA's
recommendations as to legislation regarding such remaining risk. The
EPA prepared and submitted the Residual Risk Report to Congress, EPA-
453/R-99-001 (Risk Report) in March 1999. Section 112(f)(2) then
provides that if Congress does not act on any recommendation in the
Report, EPA must analyze and address residual risk for each category or
subcategory of sources within 8 years after promulgation of such
standards pursuant to section 112(d).
Section 112(f)(2) of the CAA requires the EPA to determine for
source categories subject to MACT standards whether the emission
standards provide an ample margin of safety to protect public health.
Section 112(f)(2)(B) of the CAA expressly preserves the EPA's use of
the two-step process for developing standards to address any residual
risk and the agency's interpretation of ``ample margin of safety''
developed in the National Emissions Standards for Hazardous Air
Pollutants: Benzene Emissions from Maleic Anhydride Plants,
Ethylbenzene/Styrene Plants, Benzene Storage Vessels, Benzene Equipment
Leaks, and Coke By-Product Recovery Plants (Benzene NESHAP) (54 FR
38044, September 14, 1989). The EPA notified Congress in the Risk
Report that the agency intended to use the Benzene NESHAP approach in
making CAA section 112(f) residual risk determinations (EPA-453/R-99-
001, p. ES-11). The EPA subsequently adopted this approach in its
residual risk determinations and in a challenge to the risk review for
the Synthetic Organic Chemical Manufacturing source category, the
United States Court of Appeals for the District of Columbia Circuit
upheld as reasonable the EPA's interpretation that subsection 112(f)(2)
incorporates the approach established in the Benzene NESHAP. See NRDC
v. EPA, 529 F.3d 1077, 1083 (D.C. Cir. 2008)(``[S]ubsection
112(f)(2)(B) expressly incorporates the EPA's interpretation of the
Clean Air Act from the Benzene standard, complete with a citation to
the Federal Register.''); see also A Legislative History of the Clean
Air Act Amendments of 1990, vol. 1, p. 877 (Senate debate on Conference
Report).
The first step in the process of evaluating residual risk is the
determination of acceptable risk. If risks are unacceptable, the EPA
cannot consider cost in identifying the emissions standards necessary
to bring risks to an acceptable level. The second step is the
determination of whether standards must be further revised in order to
provide an ample margin of safety to protect public health. The ample
margin of safety is the level at which the standards must be set,
unless an even more stringent standard is necessary to prevent, taking
into consideration costs, energy, safety and other relevant factors, an
adverse environmental effect.
1. Step 1--Determination of Acceptability
The agency in the Benzene NESHAP concluded that ``the acceptability
of risk under section 112 is best judged on the basis of a broad set of
health risk measures and information'' and that the ``judgment on
acceptability cannot be reduced to any single factor.'' Benzene NESHAP
at 38046. The determination of what represents an ``acceptable'' risk
is based on a judgment of ``what risks are acceptable in the world in
which we live'' (Risk Report at 178, quoting NRDC v. EPA, 824 F. 2d
1146, 1165 (D.C. Cir. 1987) (en banc) (``Vinyl Chloride''), recognizing
that our world is not risk-free.
In the Benzene NESHAP, we stated that ``EPA will generally presume
that if the risk to [the maximum exposed] individual is no higher than
approximately one in 10 thousand, that risk level is considered
acceptable.'' 54 FR at 38045, September 14, 1989. We discussed the
maximum individual lifetime cancer risk (or maximum individual risk
(MIR)) as being ``the estimated risk that a person living near a plant
would have if he or she were exposed to the maximum pollutant
concentrations for 70 years.'' Id. We explained that this measure of
risk ``is an estimate of the upper bound of risk based on conservative
assumptions, such as continuous exposure for 24 hours per day for 70
years.'' Id. We acknowledged that maximum individual lifetime cancer
risk ``does not necessarily reflect the true risk, but displays a
conservative risk level which is an upper-bound that is unlikely to be
exceeded.'' Id.
Understanding that there are both benefits and limitations to using
the MIR as a metric for determining acceptability, we acknowledged in
the Benzene NESHAP that ``consideration of maximum individual risk * *
* must take into account the strengths and weaknesses of this measure
of risk.'' Id. Consequently, the presumptive risk level of 100-in-1
million (1-in-10 thousand) provides a benchmark for judging the
acceptability of maximum individual lifetime cancer risk, but does not
constitute a rigid line for making that determination. Further, in the
Benzene NESHAP, we noted that:
[p]articular attention will also be accorded to the weight of
evidence presented in the risk assessment of potential
carcinogenicity or other health effects of a pollutant. While the
same numerical risk may be estimated for an exposure to a pollutant
judged to be a known human carcinogen, and to a pollutant considered
a possible human carcinogen based on limited animal test data, the
same weight cannot be accorded to both estimates. In considering the
potential public health effects of the two pollutants, the Agency's
judgment on acceptability, including the MIR, will be influenced by
the greater weight of evidence for the known human carcinogen.
Id. at 38046. The agency also explained in the Benzene NESHAP that:
[i]n establishing a presumption for MIR, rather than a rigid line
for acceptability, the Agency intends to weigh it with a series of
other health measures and factors. These include the overall
incidence of cancer or other serious health effects within the
exposed population, the numbers of persons exposed within each
individual lifetime risk range and associated incidence within,
typically, a 50 km exposure radius around facilities, the science
policy assumptions and
[[Page 37854]]
estimation uncertainties associated with the risk measures, weight
of the scientific evidence for human health effects, other
quantified or unquantified health effects, effects due to co-
location of facilities, and co-emission of pollutants.
Id. At 38045. In some cases, these health measures and factors taken
together may provide a more realistic description of the magnitude of
risk in the exposed population than that provided by maximum individual
lifetime cancer risk alone.
As noted earlier, in NRDC v. EPA, the court held that section
112(f)(2) ``incorporates the EPA's interpretation of the Clean Air Act
from the Benzene Standard.'' The court further held that Congress'
incorporation of the Benzene standard applies equally to carcinogens
and non-carcinogens. 529 F.3d at 1081-82. Accordingly, we also consider
non-cancer risk metrics in our determination of risk acceptability and
ample margin of safety.
2. Step 2--Determination of Ample Margin of Safety
CAA section 112(f)(2) requires the EPA to determine, for source
categories subject to MACT standards, whether those standards provide
an ample margin of safety to protect public health. As explained in the
Benzene NESHAP, ``the second step of the inquiry, determining an `ample
margin of safety,' again includes consideration of all of the health
factors, and whether to reduce the risks even further . . . . Beyond
that information, additional factors relating to the appropriate level
of control will also be considered, including costs and economic
impacts of controls, technological feasibility, uncertainties and any
other relevant factors. Considering all of these factors, the agency
will establish the standard at a level that provides an ample margin of
safety to protect the public health, as required by section 112.'' 54
FR at 38046, September 14, 1989.
According to CAA section 112(f)(2)(A), if the MACT standards for
HAP ``classified as a known, probable, or possible human carcinogen do
not reduce lifetime excess cancer risks to the individual most exposed
to emissions from a source in the category or subcategory to less than
one in one million,'' the EPA must promulgate residual risk standards
for the source category (or subcategory), as necessary to provide an
ample margin of safety to protect public health. In doing so, the EPA
may adopt standards equal to existing MACT standards if the EPA
determines that the existing standards (i.e., the MACT standards) are
sufficiently protective. NRDC v. EPA, 529 F.3d 1077, 1083 (D.C. Cir.
2008) (``If EPA determines that the existing technology-based standards
provide an `ample margin of safety,' then the Agency is free to readopt
those standards during the residual risk rulemaking.'') The EPA must
also adopt more stringent standards, if necessary, to prevent an
adverse environmental effect,\2\ but must consider cost, energy, safety
and other relevant factors in doing so.
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\2\ ``Adverse environmental effect'' is defined as any
significant and widespread adverse effect, which may be reasonably
anticipated to wildlife, aquatic life or natural resources,
including adverse impacts on populations of endangered or threatened
species or significant degradation of environmental qualities over
broad areas. CAA section 112(a)(7).
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The CAA does not specifically define the terms ``individual most
exposed,'' ``acceptable level'' and ``ample margin of safety.'' In the
Benzene NESHAP, 54 FR at 38044-38045, September 14, 1989, we stated as
an overall objective:
In protecting public health with an ample margin of safety under
section 112, EPA strives to provide maximum feasible protection
against risks to health from hazardous air pollutants by (1)
protecting the greatest number of persons possible to an individual
lifetime risk level no higher than approximately 1-in-1 million and
(2) limiting to no higher than approximately 1-in-10 thousand [i.e.,
100-in-1 million] the estimated risk that a person living near a
plant would have if he or she were exposed to the maximum pollutant
concentrations for 70 years.
The agency further stated that ``[t]he EPA also considers incidence
(the number of persons estimated to suffer cancer or other serious
health effects as a result of exposure to a pollutant) to be an
important measure of the health risk to the exposed population.
Incidence measures the extent of health risks to the exposed population
as a whole, by providing an estimate of the occurrence of cancer or
other serious health effects in the exposed population.'' Id. at 38045.
In the ample margin of safety decision process, the agency again
considers all of the health risks and other health information
considered in the first step, including the incremental risk reduction
associated with standards more stringent than the MACT standard or a
more stringent standard that the EPA has determined is necessary to
ensure risk is acceptable. In the ample margin of safety analysis, the
agency considers additional factors, including costs and economic
impacts of controls, technological feasibility, uncertainties and any
other relevant factors. Considering all of these factors, the agency
will establish the standard at a level that provides an ample margin of
safety to protect the public health, as required by CAA section 112(f).
54 FR 38046, September 14, 1989.
B. What is this source category and how does the current NESHAP
regulate its HAP emissions?
The NESHAP for OSWRO was proposed on October 13, 1994 (59 FR
51913), promulgated on July 1, 1996 (61 FR 34140), and codified at 40
CFR part 63, subpart DD. The final rule was amended on July 20, 1999
(64 FR 38950). In general, the rule applies to waste management units
and recovery operations that are: (1) Located at major sources of HAP
emissions; and (2) used to manage, convey or handle used oil, used
solvent or waste received from other facilities and that contain at
least one of 97 organic HAP specified in the rule.\3\ The HAP emission
sources at facilities subject to the OSWRO NESHAP are tanks,
containers, surface impoundments, oil-water separators, organic-water
separators, process vents and transfer systems used to manage off-site
material and equipment leaks. The MACT standards regulate these
emissions sources through emission limits, equipment standards and work
practices.
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\3\ The OSWRO MACT rule defines ``waste,'' ``used oil'' and
``used solvent'' in 40 CFR 63.681 Definitions.
---------------------------------------------------------------------------
C. What data collection activities were conducted to support this
action?
Under the authority of CAA section 114, we sent questionnaires to
nine companies that own and operate OSWRO facilities. In the CAA
section 114 questionnaires, we asked for information about process
equipment, control devices, work practices, associated emission
reductions, point and fugitive emissions, and other aspects of facility
operations. We visited three facilities, and reviewed permit data from
18 state and local agencies. In addition, we reviewed several EPA
databases to identify facilities that may be part of the source
category. We also reviewed data in the EPA's National Emissions
Inventory (NEI) to identify emission sources and quantities of
emissions and the Toxics Release Inventory (TRI) to verify emissions
estimates.
The data gathered through these activities are described further in
the memorandum Development of the RTR Emissions Dataset for the Off-
Site Waste and Recovery Operations Source Category, which is available
in the docket for this proposed rule.
[[Page 37855]]
III. Analytical Procedures
In this section, we describe the analyses performed to support the
proposed decisions for the RTR and other issues addressed in this
proposal.
A. How did we estimate post-MACT risks posed by the source category?
The EPA conducted a risk assessment that provides estimates of the
MIR posed by the HAP emissions from each source in the source category,
the hazard index (HI) for chronic exposures to HAP with the potential
to cause non-cancer health effects, and the hazard quotient (HQ) for
acute exposures to HAP with the potential to cause non-cancer health
effects. The assessment also provides estimates of the distribution of
cancer risks within the exposed populations, cancer incidence and an
evaluation of the potential for adverse environmental effects for the
source category. The eight sections that follow this paragraph describe
how we estimated emissions and conducted the risk assessment. The
docket for this proposed rule contains the following document which
provides more information on the risk assessment inputs and models:
Draft Residual Risk Assessment for the Off-Site Waste and Recovery
Operations Source Category. The methods used to assess risks (as
described in the eight primary steps below) are consistent with those
peer-reviewed by a panel of the EPA's Science Advisory Board (SAB) in
2009 and described in their peer review report issued in 2010 \4\; they
are also consistent with the key recommendations contained in that
report.
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\4\ U.S. EPA SAB. Risk and Technology Review (RTR) Risk
Assessment Methodologies: For Review by the EPA's Science Advisory
Board with Case Studies--MACT I Petroleum Refining Sources and
Portland Cement Manufacturing, May 2010.
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1. How did we estimate actual emissions and identify the emissions
release characteristics?
Data for 38 OSWRO facilities were used to create an RTR emissions
dataset (i.e., risk model input file). This RTR emissions dataset is
based on a combination of data gathered through the CAA section 114
questionnaire and the 2005 NEI. The NEI is a database that contains
information about sources that emit criteria air pollutants, their
precursors and HAP. The database includes estimates of annual air
pollutant emissions from point, nonpoint and mobile sources in the 50
states, the District of Columbia, Puerto Rico and the Virgin Islands.
The EPA collects this information and releases an updated version of
the NEI database every 3 years. The NEI includes information necessary
for conducting risk modeling, including annual HAP emissions estimates
from individual emission points at facilities and the related emissions
release parameters. Other databases, including the TRI and Envirofacts,
were consulted to verify emissions estimates and to identify facilities
that are part of the OSWRO source category. As part of our quality
assurance review, we reviewed the emissions data and release
characteristics data in the RTR emissions dataset to ensure the data
were accurate. We also checked the coordinates of each emission source
in the dataset using tools such as Google Earth and ArcView to ensure
the emission point locations were correct.
While data for 38 OSWRO facilities were included in the RTR
emissions dataset, available data indicate there are 52 currently
operating major source facilities that are subject to the OSWRO MACT
standards. The remaining 14 facilities were not included in the
modeling file because the information available to the EPA, including
the NEI, did not attribute any amount of HAP emissions to off-site
waste and recovery operations at these facilities. It was also not
possible to discern from the emission point identifiers or
characteristics in the inventory which emissions could be attributed to
the OSWRO source category. We note that available permit information
indicates that five of these 14 facilities are only subject to off-site
waste HAP content determination requirements and are not subject to the
emissions standards and other requirements of the OSWRO NESHAP due to
the low amount of HAP in the off-site waste accepted by these
facilities. Also, available permit data indicates that two additional
facilities are not subject to the emissions standards and other
requirements of the OSWRO NESHAP because they comply instead with 40
CFR part 61, subpart FF, as allowed by the OSWRO NESHAP. For these
seven facilities, we would not expect any emission points to be labeled
as OSWRO emission points in the NEI because those emission points are
not subject to any OSWRO MACT emissions standards. We also did not
collect data from these facilities through our CAA section 114
questionnaire. As noted in section VI of this preamble, we are
requesting site-specific emissions data that would enable us to better
characterize the maximum risks from the OSWRO source category. A list
of the 52 facilities and additional information about the development
of the RTR emissions dataset is provided in the technical document:
Development of the RTR Emissions Dataset for the Off-Site Waste and
Recovery Operations Source Category, which is available in the docket
for this action.
2. How did we estimate MACT-allowable emissions?
The available emissions data in the RTR emissions dataset include
estimates of the mass of HAP emitted during the specified annual time
period. In some cases, these ``actual'' emission levels are lower than
the emission levels required to comply with the MACT standards. The
emissions level allowed to be emitted by the MACT standards is referred
to as the ``MACT-allowable'' emissions level. We discussed the use of
both MACT-allowable and actual emissions in the final Coke Oven
Batteries residual risk rule (70 FR 19998-19999, April 15, 2005) and in
the proposed and final Hazardous Organic NESHAP residual risk rules (71
FR 34428, June 14, 2006, and 71 FR 76609, December 21, 2006,
respectively). In those previous actions, we noted that assessing the
risks at the MACT-allowable level is inherently reasonable since these
risks reflect the maximum level facilities could emit and still comply
with national emission standards. We also explained that it is
reasonable to consider actual emissions, where such data are available,
in both steps of the risk analysis, in accordance with the Benzene
NESHAP approach. (54 FR 38044, September 14, 1989.)
We used the emissions data gathered from the 2005 NEI and responses
to the CAA section 114 questionnaire to estimate the MACT-allowable
emissions levels. We estimate that the actual emissions level is
representative of the MACT-allowable level for all emissions sources
except tanks and process vents. Based on responses to the CAA section
114 questionnaire, we estimate that MACT-allowable emissions from tanks
and process vents could be up to five times the actual emissions. For
some facilities, we cannot assign HAP emissions to a specific type of
emission source (e.g., a process vent) due to a lack of specificity in
the emission point identifiers in the NEI. For facilities where we
could identify specific emission source types, we applied a factor of 5
to the actual emissions attributable to tanks and process vents. A
factor of 1 was applied to the actual emissions for other emissions
sources (e.g., equipment leaks). For facilities where we could not
identify specific emission source types, we developed and applied a
factor of 2.5 to all the OSWRO emissions. The 2.5 factor is
[[Page 37856]]
based on the factor of 5 for tanks and process vents and information
from the responses to the CAA section 114 questionnaire indicating that
tank and process vent emissions comprise approximately half of the
total OSWRO emissions.
For more detail about this estimate of the MACT-allowable
emissions, see the memorandum, MACT-Allowable Emissions for the Off-
Site Waste and Recovery Operations Source Category, which is available
in the docket for this action.
3. How did we conduct dispersion modeling, determine inhalation
exposures and estimate individual and population inhalation risks?
Both long-term and short-term inhalation exposure concentrations
and health risks from the source category addressed in this proposal
were estimated using the Human Exposure Model (Community and Sector
HEM-3 version 1.1.0). The HEM-3 performs three primary risk assessment
activities: (1) Conducting dispersion modeling to estimate the
concentrations of HAP in ambient air, (2) estimating long-term and
short-term inhalation exposures to individuals residing within 50
kilometers (km) of the modeled sources \5\, and (3) estimating
individual and population-level inhalation risks using the exposure
estimates and quantitative dose-response information.
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\5\ This metric comes from the Benzene NESHAP. See 54 FR 38046.
---------------------------------------------------------------------------
The air dispersion model used by the HEM-3 model (AERMOD) is one of
the EPA's preferred models for assessing pollutant concentrations from
industrial facilities.\6\ To perform the dispersion modeling and to
develop the preliminary risk estimates, HEM-3 draws on three data
libraries. The first is a library of meteorological data, which is used
for dispersion calculations. This library includes 1 year (2011) of
hourly surface and upper air observations for more than 800
meteorological stations, selected to provide coverage of the United
States and Puerto Rico. A second library of United States Census Bureau
census block \7\ internal point locations and populations provides the
basis of human exposure calculations (U.S. Census, 2010). In addition,
for each census block, the census library includes the elevation and
controlling hill height, which are also used in dispersion
calculations. A third library of pollutant unit risk factors and other
health benchmarks is used to estimate health risks. These risk factors
and health benchmarks are the latest values recommended by the EPA for
HAP and other toxic air pollutants. These values are available at:
http://www.epa.gov/ttn/atw/toxsource/summary.html and are discussed in
more detail later in this section.
---------------------------------------------------------------------------
\6\ U.S. EPA. Revision to the Guideline on Air Quality Models:
Adoption of a Preferred General Purpose (Flat and Complex Terrain)
Dispersion Model and Other Revisions (70 FR 68218, November 9,
2005).
\7\ A census block is the smallest geographic area for which
census statistics are tabulated.
---------------------------------------------------------------------------
In developing the risk assessment for chronic exposures, we used
the estimated annual average ambient air concentrations of each HAP
emitted by each source for which we have emissions data in the source
category. The air concentrations at each nearby census block centroid
were used as a surrogate for the chronic inhalation exposure
concentration for all the people who reside in that census block. We
calculated the MIR for each facility as the cancer risk associated with
a continuous lifetime (24 hours per day, 7 days per week, and 52 weeks
per year for a 70-year period) exposure to the maximum concentration at
the centroid of inhabited census blocks. Individual cancer risks were
calculated by multiplying the estimated lifetime exposure to the
ambient concentration of each of the HAP (in micrograms per cubic meter
([mu]g/m\3\)) by its unit risk estimate (URE). The URE is an upper
bound estimate of an individual's probability of contracting cancer
over a lifetime of exposure to a concentration of 1 microgram of the
pollutant per cubic meter of air. For residual risk assessments, we
generally use URE values from the EPA's Integrated Risk Information
System (IRIS). For carcinogenic pollutants without EPA IRIS values, we
look to other reputable sources of cancer dose-response values, often
using California EPA (CalEPA) URE values, where available. In cases
where new, scientifically credible dose response values have been
developed in a manner consistent with the EPA guidelines and have
undergone a peer review process similar to that used by the EPA, we may
use such dose-response values in place of, or in addition to, other
values, if appropriate.
The EPA estimated incremental individual lifetime cancer risks
associated with emissions from the facilities in the source category as
the sum of the risks for each of the carcinogenic HAP (including those
classified as carcinogenic to humans, likely to be carcinogenic to
humans, and suggestive evidence of carcinogenic potential \8\) emitted
by the modeled sources. Cancer incidence and the distribution of
individual cancer risks for the population within 50 km of the sources
were also estimated for the source category as part of this assessment
by summing individual risks. A distance of 50 km is consistent with
both the analysis supporting the 1989 Benzene NESHAP (54 FR 38044,
September 14, 1989) and the limitations of Gaussian dispersion models,
including AERMOD.
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\8\ These classifications also coincide with the terms ``known
carcinogen, probable carcinogen, and possible carcinogen,''
respectively, which are the terms advocated in the EPA's previous
Guidelines for Carcinogen Risk Assessment, published in 1986 (51 FR
33992, September 24, 1986). Summing the risks of these individual
compounds to obtain the cumulative cancer risks is an approach that
was recommended by the EPA's Science Advisory Board (SAB) in their
2002 peer review of EPA's National Air Toxics Assessment (NATA)
entitled, NATA--Evaluating the National-scale Air Toxics Assessment
1996 Data--an SAB Advisory, available at: http://yosemite.epa.gov/
sab/sabproduct.nsf/214C6E915BB04E14852570CA007A682C/$File/
ecadv02001.pdf.
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To assess the risk of non-cancer health effects from chronic
exposures, we summed the HQ for each of the HAP that affects a common
target organ system to obtain the HI for that target organ system (or
target organ-specific HI, TOSHI). The HQ is the estimated exposure
divided by the chronic reference value, which is a value selected from
one of several sources. First, the chronic reference level can be the
EPA reference concentration (RfC), (http://www.epa.gov/riskassessment/glossary.htm), defined as ``an estimate (with uncertainty spanning
perhaps an order of magnitude) of a continuous inhalation exposure to
the human population (including sensitive subgroups) that is likely to
be without an appreciable risk of deleterious effects during a
lifetime.'' Alternatively, in cases where an RfC from the EPA's IRIS
database is not available, or where the EPA determines that using a
value other than the RfC is appropriate, the chronic reference level
can be a value from the following prioritized sources: (1) The Agency
for Toxic Substances and Disease Registry Minimum Risk Level (http://www.atsdr.cdc.gov/mrls/index.asp), which is defined as ``an estimate of
daily human exposure to a hazardous substance that is likely to be
without an appreciable risk of adverse non-cancer health effects (other
than cancer) over a specified duration of exposure''; (2) the CalEPA
Chronic Reference Exposure Level (REL) (http://www.oehha.ca.gov/air/hot_spots/pdf/HRAguidefinal.pdf), which is defined as ``the
concentration level (that is expressed in units of micrograms per
[[Page 37857]]
cubic meter ([mu]g/m3) for inhalation exposure and in a dose expressed
in units of milligram per kilogram-day (mg/kg-day) for oral exposures),
at or below which no adverse health effects are anticipated for a
specified exposure duration''; or (3) as noted above, a scientifically
credible dose-response value that has been developed in a manner
consistent with the EPA guidelines and has undergone a peer review
process similar to that used by the EPA, in place of or in concert with
other values.
The EPA also evaluated screening estimates of acute exposures and
risks for each of the HAP at the point of highest off-site exposure for
each facility (i.e., not just the census block centroids), assuming
that a person is located at this spot at a time when both the peak
(hourly) emissions rate and worst-case dispersion conditions occur. The
acute HQ is the estimated acute exposure divided by the acute dose-
response value. In each case, the EPA calculated acute HQ values using
best available, short-term dose-response values. These acute dose-
response values, which are described below, include the acute REL,
acute exposure guideline levels (AEGL) and emergency response planning
guidelines (ERPG) for 1-hour exposure durations. As discussed below, we
used conservative assumptions for emissions rates, meteorology and
exposure location for our acute analysis.
As described in the CalEPA's Air Toxics Hot Spots Program Risk
Assessment Guidelines, Part I, The Determination of Acute Reference
Exposure Levels for Airborne Toxicants, an acute REL value (http://www.oehha.ca.gov/air/pdf/acuterel.pdf) is defined as, ``the
concentration level at or below which no adverse health effects are
anticipated for a specified exposure duration.'' Id. at page 2. Acute
REL values are based on the most sensitive, relevant, adverse health
effect reported in the peer-reviewed medical and toxicological
literature. Acute REL values are designed to protect the most sensitive
individuals in the population through the inclusion of margins of
safety. Because margins of safety are incorporated to address data gaps
and uncertainties, exceeding the REL does not automatically indicate an
adverse health impact.
AEGL values were derived in response to recommendations from the
National Research Council (NRC). As described in Standing Operating
Procedures (SOP) of the National Advisory Committee on Acute Exposure
Guideline Levels for Hazardous Substances (http://www.epa.gov/oppt/aegl/pubs/sop.pdf),\9\ ``the NRC's previous name for acute exposure
levels--community emergency exposure levels--was replaced by the term
AEGL to reflect the broad application of these values to planning,
response, and prevention in the community, the workplace,
transportation, the military, and the remediation of Superfund sites.''
Id. at 2. This document also states that AEGL values ``represent
threshold exposure limits for the general public and are applicable to
emergency exposures ranging from 10 minutes to eight hours.'' Id. at 2.
---------------------------------------------------------------------------
\9\ National Academy of Sciences (NAS), 2001. Standing Operating
Procedures for Developing Acute Exposure Levels for Hazardous
Chemicals, page 2.
---------------------------------------------------------------------------
The document lays out the purpose and objectives of AEGL by stating
that ``the primary purpose of the AEGL program and the National
Advisory Committee for Acute Exposure Guideline Levels for Hazardous
Substances is to develop guideline levels for once-in-a-lifetime,
short-term exposures to airborne concentrations of acutely toxic, high-
priority chemicals.'' Id. at 21. In detailing the intended application
of AEGL values, the document states that ``[i]t is anticipated that the
AEGL values will be used for regulatory and non-regulatory purposes by
U.S. Federal and state agencies and possibly the international
community in conjunction with chemical emergency response, planning,
and prevention programs. More specifically, the AEGL values will be
used for conducting various risk assessments to aid in the development
of emergency preparedness and prevention plans, as well as real-time
emergency response actions, for accidental chemical releases at fixed
facilities and from transport carriers.'' Id. at 31.
The AEGL-1 value is then specifically defined as ``the airborne
concentration (expressed as ppm (parts per million) or mg/m3
(milligrams per cubic meter)) of a substance above which it is
predicted that the general population, including susceptible
individuals, could experience notable discomfort, irritation, or
certain asymptomatic non-sensory effects. However, the effects are not
disabling and are transient and reversible upon cessation of
exposure.'' Id. at 3. The document also notes that, ``Airborne
concentrations below AEGL-1 represent exposure levels that can produce
mild and progressively increasing but transient and non-disabling odor,
taste, and sensory irritation or certain asymptomatic, non-sensory
effects.'' Id. Similarly, the document defines AEGL-2 values as ``the
airborne concentration (expressed as parts per million or milligrams
per cubic meter) of a substance above which it is predicted that the
general population, including susceptible individuals, could experience
irreversible or other serious, long-lasting adverse health effects or
an impaired ability to escape.'' Id.
ERPG values are derived for use in emergency response, as described
in the American Industrial Hygiene Association's ERP Committee document
entitled, ERPGS Procedures and Responsibilities (http://sp4m.aiha.org/insideaiha/GuidelineDevelopment/ERPG/Documents/ERP-SOPs2006.pdf), which
states that, ``Emergency Response Planning Guidelines were developed
for emergency planning and are intended as health based guideline
concentrations for single exposures to chemicals.'' \10\ Id. at 1. The
ERPG-1 value is defined as ``the maximum airborne concentration below
which it is believed that nearly all individuals could be exposed for
up to 1 hour without experiencing other than mild transient adverse
health effects or without perceiving a clearly defined, objectionable
odor.'' Id. at 2. Similarly, the ERPG-2 value is defined as ``the
maximum airborne concentration below which it is believed that nearly
all individuals could be exposed for up to one hour without
experiencing or developing irreversible or other serious health effects
or symptoms which could impair an individual's ability to take
protective action.'' Id. at 1.
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\10\ ERP Committee Procedures and Responsibilities. November 1,
2006. American Industrial Hygiene Association.
---------------------------------------------------------------------------
As can be seen from the definitions above, the AEGL and ERPG values
include the similarly-defined severity levels 1 and 2. For many
chemicals, a severity level 1 value AEGL or ERPG has not been developed
because the types of effects for these chemicals are not consistent
with the AEGL-1/ERPG-1 definitions; in these instances, we compare
higher severity level AEGL-2 or ERPG-2 values to our modeled exposure
levels to screen for potential acute concerns. When AEGL-1/ERPG-1
values are available, they are used in our acute risk assessments.
Acute REL values for 1-hour exposure durations are typically lower
than their corresponding AEGL-1 and ERPG-1 values. Even though their
definitions are slightly different, AEGL-1 values are often the same as
the corresponding ERPG-1 values, and AEGL-2 values are often equal to
ERPG-2 values. Maximum HQ values from our acute screening risk
assessments typically
[[Page 37858]]
result when basing them on the acute REL value for a particular
pollutant. In cases where our maximum acute HQ value exceeds 1, we also
report the HQ value based on the next highest acute dose-response value
(usually the AEGL-1 and/or the ERPG-1 value).
To develop screening estimates of acute exposures in the absence of
hourly emissions data, generally we first develop estimates of maximum
hourly emissions rates by multiplying the average actual annual hourly
emissions rates by a default factor to cover routinely variable
emissions. We choose the factor to use partially based on process
knowledge and engineering judgment. The factor chosen also reflects a
Texas study of short-term emissions variability, which showed that most
peak emission events in a heavily-industrialized four-county area
(Harris, Galveston, Chambers and Brazoria Counties, Texas) were less
than twice the annual average hourly emissions rate. The highest peak
emissions event was 74 times the annual average hourly emissions rate,
and the 99th percentile ratio of peak hourly emissions rate to the
annual average hourly emissions rate was 9.\11\ Considering this
analysis, to account for more than 99 percent of the peak hourly
emissions, we apply a conservative screening multiplication factor of
10 to the average annual hourly emissions rate in our acute exposure
screening assessments as our default approach. However, we use a factor
other than 10 if we have information that indicates that a different
factor is appropriate for a particular source category. For this source
category, there was no such information available and the default
factor of 10 was used in the acute screening process.
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\11\ See http://www.tceq.state.tx.us/compliance/field_ops/eer/index.html or docket to access the source of these data.
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As part of our acute risk assessment process, for cases where acute
HQ values from the screening step were less than or equal to 1 (even
under the conservative assumptions of the screening analysis), acute
impacts were deemed negligible and no further analysis was performed.
In cases where an acute HQ from the screening step was greater than 1,
additional site-specific data were considered to develop a more refined
estimate of the potential for acute impacts of concern. For this source
category, there were no offsite acute values greater than 1, and no
refined estimates were developed. Ideally, we would prefer to have
continuous measurements over time to see how the emissions vary by each
hour over an entire year. Having a frequency distribution of hourly
emissions rates over a year would allow us to perform a probabilistic
analysis to estimate potential threshold exceedances and their
frequency of occurrence. Such an evaluation could include a more
complete statistical treatment of the key parameters and elements
adopted in this screening analysis. Recognizing that this level of data
is rarely available, we instead rely on the multiplier approach.
To better characterize the potential health risks associated with
estimated acute exposures to HAP, and in response to a key
recommendation from the SAB's peer review of the EPA's RTR risk
assessment methodologies,\12\ we generally examine a wider range of
available acute health metrics (e.g., RELs, AEGLs) than we do for our
chronic risk assessments. This is in response to the SAB's
acknowledgement that there are generally more data gaps and
inconsistencies in acute reference values than there are in chronic
reference values. In some cases, when Reference Value Arrays \13\ for
HAP have been developed, we consider additional acute values (i.e.,
occupational and international values) to provide a more complete risk
characterization.
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\12\ The SAB peer review of RTR Risk Assessment Methodologies is
available at: http://yosemite.epa.gov/sab/sabproduct.nsf/
4AB3966E263D943A8525771F00668381/$File/EPA-SAB-10-007-unsigned.pdf.
\13\ U.S. EPA. (2009) Chapter 2.9 Chemical Specific Reference
Values for Formaldehyde in Graphical Arrays of Chemical-Specific
Health Effect Reference Values for Inhalation Exposures (Final
Report). U.S. Environmental Protection Agency, Washington DC, EPA/
600/R-09/061, and available online at http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=211003.
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4. How did we conduct the multipathway exposure and risk screening?
The EPA conducted a screening analysis examining the potential for
significant human health risks due to exposures via routes other than
inhalation (i.e., ingestion). Initially, we determined whether any
sources in the source category emitted any hazardous air pollutants
known to be persistent and bioaccumulative in the environment (PB-HAP).
The PB-HAP compounds or compound classes are identified for the
screening from the EPA's Air Toxics Risk Assessment Library (available
at http://www.epa.gov/ttn/fera/risk_atra_vol1.html).
For the OSWRO source category, we identified emissions of
polycyclic organic matter (POM) (analyzed as benzo(a)pyrene toxicity
equivalence factor (TEQ)), polychlorinated biphenyls,
hexachlorobenzene, chlordane, lindane (gamma hch), methoxyclor,
toxaphene, heptachlor, and trifluralin. Because one or more of these
PB-HAP are emitted by at least one facility in the OSWRO source
category, we proceeded to the next step of the evaluation. In this
step, we determined whether the facility-specific emissions rates of
the emitted PB-HAP were large enough to create the potential for
significant non-inhalation human health risks under reasonable worst-
case conditions. To facilitate this step, we developed emissions rate
thresholds for several PB-HAP using a hypothetical upper-end screening
exposure scenario developed for use in conjunction with the EPA's Total
Risk Integrated Methodology. Fate, Transport, and Ecological Exposure
(TRIM.FaTE) model. The PB-HAP with emissions rate thresholds are: Lead,
cadmium, chlorinated dibenzodioxins and furans, mercury compounds, and
polycyclic organic matter (POM). We conducted a sensitivity analysis on
the screening scenario to ensure that its key design parameters would
represent the upper end of the range of possible values, such that it
would represent a conservative but not impossible scenario. The
facility-specific emissions rates of these PB-HAP were compared to the
emission rate threshold values for these PB-HAP to assess the potential
for significant human health risks via non-inhalation pathways. We call
this application of the TRIM.FaTE model the Tier I TRIM-screen or Tier
I screen.
For the purpose of developing emissions rates for our Tier I TRIM-
screen, we derived emission levels for these PB-HAP (other than lead
compounds) at which the maximum excess lifetime cancer risk would be 1-
in-1 million (i.e., for polychlorinated dibenzodioxins and furans and
POM) or, for HAP that cause non-cancer health effects (i.e., cadmium
compounds and mercury compounds), the maximum hazard quotient would be
1. If the emissions rate of any PB-HAP included in the Tier I screen
exceeds the Tier I screening emissions rate for any facility, we
conduct a second screen, which we call the Tier II TRIM-screen or Tier
II screen. In the Tier II screen, the location of each facility that
exceeded the Tier I emission rate is used to refine the assumptions
associated with the environmental scenario while maintaining the
exposure scenario assumptions. We then adjust the risk-based Tier I
screening level for each PB-HAP for each facility based on an
understanding of how exposure concentrations estimated for the
[[Page 37859]]
screening scenario change with meteorology and environmental
assumptions. PB-HAP emissions that do not exceed these new Tier II
screening levels are considered to pose no unacceptable risks. When
facilities exceed the Tier II screening levels, it does not mean that
multipathway impacts are significant, only that we cannot rule out that
possibility based on the results of the screen. These facilities may be
further evaluated for multipathway risks using the TRIM.FaTE model.
For further information on the multipathway analysis approach, see
the Draft Residual Risk Assessment for the Off-Site Waste and Recovery
Operations Source Category, which is available in the docket for this
action.
5. How did we assess risks considering emissions control options?
In addition to assessing baseline inhalation risks and screening
for potential multipathway risks, we also estimated risks considering
the potential emission reductions that would be achieved by the control
options under consideration. In these cases, the expected emission
reductions were applied to the specific HAP and emission points in the
RTR emissions dataset to develop corresponding estimates of risk and
incremental risk reductions.
6. How did we conduct the environmental risk screening assessment?
a. Adverse Environmental Effect
The EPA has developed a screening approach to examine the potential
for adverse environmental effects as required under section
112(f)(2)(A) of the CAA. Section 112(a)(7) of the CAA defines ``adverse
environmental effect'' as ``any significant and widespread adverse
effect, which may reasonably be anticipated, to wildlife, aquatic life,
or other natural resources, including adverse impacts on populations of
endangered or threatened species or significant degradation of
environmental quality over broad areas.''
b. Environmental HAP
The EPA focuses on seven HAP, which we refer to as ``environmental
HAP,'' in its screening analysis: Five persistent bioaccumulative HAP
(PB-HAP) and two acid gases. The five PB-HAP are cadmium, dioxins/
furans, polycyclic organic matter (POM), mercury (both inorganic
mercury and methyl mercury) and lead compounds. The two acid gases are
hydrogen chloride (HCl) and hydrogen fluoride (HF). The rationale for
including these seven HAP in the environmental risk screening analysis
is presented below.
HAP that persist and bioaccumulate are of particular environmental
concern because they accumulate in the soil, sediment and water. The
PB-HAP are taken up, through sediment, soil, water, and/or ingestion of
other organisms, by plants or animals (e.g., small fish) at the bottom
of the food chain. As larger and larger predators consume these
organisms, concentrations of the PB-HAP in the animal tissues increases
as does the potential for adverse effects. The five PB-HAP we evaluate
as part of our screening analysis account for 99.8 percent of all PB-
HAP emissions nationally from stationary sources (on a mass basis from
the 2005 NEI).
In addition to accounting for almost all of the mass of PB-HAP
emitted, we note that the TRIM.Fate model that we use to evaluate
multipathway risk allows us to estimate concentrations of cadmium
compounds, dioxins/furans, POM and mercury in soil, sediment and water.
For lead compounds, we currently do not have the ability to calculate
these concentrations using the TRIM.Fate model. Therefore, to evaluate
the potential for adverse environmental effects from lead compounds, we
compare the estimated HEM-modeled exposures from the source category
emissions of lead with the level of the secondary National Ambient Air
Quality Standard (NAAQS) for lead.\14\ We consider values below the
level of the secondary lead NAAQS to be unlikely to cause adverse
environmental effects.
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\14\ The secondary lead NAAQS is a reasonable measure of
determining whether there is an adverse environmental effect since
it was established considering ``effects on soils, water, crops,
vegetation, man-made materials, animals, wildlife, weather,
visibility and climate, damage to and deterioration of property, and
hazards to transportation, as well as effects on economic values and
on personal comfort and well-being.'' 73 FR 66964, November 12,
2008.
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Due to their well-documented potential to cause direct damage to
terrestrial plants, we include two acid gases, HCl and HF, in the
environmental screening analysis. According to the 2005 NEI, HCl and HF
account for about 99 percent (on a mass basis) of the total acid gas
HAP emitted by stationary sources in the U.S. In addition to the
potential to cause direct damage to plants, high concentrations of HF
in the air have been linked to fluorosis in livestock. Air
concentrations of these HAP are already calculated as part of the human
multipathway exposure and risk screening analysis using the HEM3-AERMOD
air dispersion model, and we are able to use the air dispersion
modeling results to estimate the potential for an adverse environmental
effect.
The EPA acknowledges that other HAP beyond the seven HAP discussed
above may have the potential to cause adverse environmental effects.
Therefore, the EPA may include other relevant HAP in its environmental
risk screening in the future, as modeling science and resources allow.
The EPA invites comment on the extent to which other HAP emitted by the
source category may cause adverse environmental effects. Such
information should include references to peer-reviewed ecological
effects benchmarks that are of sufficient quality for making regulatory
decisions, as well as information on the presence of organisms located
near facilities within the source category that such benchmarks
indicate could be adversely affected.
c. Ecological Assessment Endpoints and Benchmarks for PB-HAP
An important consideration in the development of the EPA's
screening methodology is the selection of ecological assessment
endpoints and benchmarks. Ecological assessment endpoints are defined
by the ecological entity (e.g., aquatic communities including fish and
plankton) and its attributes (e.g., frequency of mortality). Ecological
assessment endpoints can be established for organisms, populations,
communities or assemblages, and ecosystems.
For PB-HAP (other than lead compounds), we evaluated the following
community-level ecological assessment endpoints to screen for organisms
directly exposed to HAP in soils, sediment and water:
Local terrestrial communities (i.e., soil invertebrates,
plants) and populations of small birds and mammals that consume soil
invertebrates exposed to PB-HAP in the surface soil.
Local benthic (i.e., bottom sediment dwelling insects,
amphipods, isopods and crayfish) communities exposed to PB-HAP in
sediment in nearby water bodies.
Local aquatic (water-column) communities (including fish
and plankton) exposed to PB-HAP in nearby surface waters.
For PB-HAP (other than lead compounds), we also evaluated the
following population-level ecological assessment endpoint to screen for
indirect HAP exposures of top consumers via the bioaccumulation of HAP
in food chains:
Piscivorous (i.e., fish-eating) wildlife consuming PB-HAP-
[[Page 37860]]
contaminated fish from nearby water bodies.
For cadmium compounds, dioxins/furans, POM and mercury, we
identified the available ecological benchmarks for each assessment
endpoint. An ecological benchmark represents a concentration of HAP
(e.g., 0.77 ug of HAP per liter of water) that has been linked to a
particular environmental effect level (e.g., a no-observed-adverse-
effect level (NOAEL)) through scientific study. For PB-HAP, we
identified, where possible, ecological benchmarks at the following
effect levels:
Probable effect levels (PEL): Level above which adverse effects are
expected to occur frequently.
Lowest-observed-adverse-effect level (LOAEL): The lowest exposure
level tested at which there are biologically significant increases in
frequency or severity of adverse effects.
No-observed-adverse-effect levels (NOAEL): The highest exposure
level tested at which there are no biologically significant increases
in the frequency or severity of adverse effect.
We established a hierarchy of preferred benchmark sources to allow
selection of benchmarks for each environmental HAP at each ecological
assessment endpoint. In general, the EPA sources that are used at a
programmatic level (e.g., Office of Water, Superfund Program) were
used, if available. If not, the EPA benchmarks used in regional
programs (e.g., Superfund) were used. If benchmarks were not available
at a programmatic or regional level, we used benchmarks developed by
other federal agencies (e.g., National Oceanic and Atmospheric
Organization (NOAA)) or state agencies.
Benchmarks for all effect levels are not available for all PB-HAP
and assessment endpoints. In cases where multiple effect levels were
available for a particular PB-HAP and assessment endpoint, we use all
of the available effect levels to help us to determine whether
ecological risks exist and, if so, whether the risks could be
considered significant and widespread.
d. Ecological Assessment Endpoints and Benchmarks for Acid Gases
The environmental screening analysis also evaluated potential
damage and reduced productivity of plants due to direct exposure to
acid gases in the air. For acid gases, we evaluated the following
ecological assessment endpoint:
Local terrestrial plant communities with foliage exposed
to acidic gaseous HAP in the air.
The selection of ecological benchmarks for the effects of acid
gases on plants followed the same approach as for PB-HAP (i.e., we
examine all of the available chronic benchmarks). For HCl, the EPA
identified chronic benchmark concentrations. We note that the benchmark
for chronic HCl exposure to plants is greater than the reference
concentration for chronic inhalation exposure for human health. This
means that where the EPA includes regulatory requirements to prevent an
exceedance of the reference concentration for human health, additional
analyses for adverse environmental effects of HCL would not be
necessary.
For HF, the EPA identified chronic benchmark concentrations for
plants and evaluated chronic exposures to plants in the screening
analysis. High concentrations of HF in the air have also been linked to
fluorosis in livestock. However, the HF concentrations at which
fluorosis in livestock occur are higher than those at which plant
damage begins. Therefore, the benchmarks for plants are protective of
both plants and livestock.
e. Screening Methodology
For the environmental risk screening analysis, the EPA first
determined whether any facilities in the OSWRO source category emitted
any of the seven environmental HAP. For the OSWRO source category, we
identified emissions of POM, HCl and HF.
Because one or more of the seven environmental HAP evaluated are
emitted by at least one facility in the source category, we proceeded
to the second step of the evaluation.
f. PB-HAP Methodology
For cadmium, mercury, POM and dioxins/furans, the environmental
screening analysis consists of two tiers, while lead compounds are
analyzed differently as discussed earlier. In the first tier, we
determined whether the maximum facility-specific emission rates of each
of the emitted environmental HAP were large enough to create the
potential for adverse environmental effects under reasonable worst-case
environmental conditions. These are the same environmental conditions
used in the human multipathway exposure and risk screening analysis.
To facilitate this step, TRIM.FaTE was run for each PB-HAP under
hypothetical environmental conditions designed to provide
conservatively high HAP concentrations. The model was set to maximize
runoff from terrestrial parcels into the modeled lake, which in turn,
maximized the chemical concentrations in the water, the sediments, and
the fish. The resulting media concentrations were then used to back-
calculate a screening threshold emission rate that corresponded to the
relevant exposure benchmark concentration value for each assessment
endpoint. To assess emissions from a facility, the reported emission
rate for each PB-HAP was compared to the screening threshold emission
rate for that PB-HAP for each assessment endpoint. If emissions from a
facility do not exceed the Tier I threshold, the facility ``passes''
the screen, and therefore, is not evaluated further under the screening
approach. If emissions from a facility exceed the Tier I threshold, we
evaluate the facility further in Tier II.
In Tier II of the environmental screening analysis, the screening
emission thresholds are adjusted to account for local meteorology and
the actual location of lakes in the vicinity of facilities that did not
pass the Tier I screen. The modeling domain for each facility in the
Tier II analysis consists of eight octants. Each octant contains 5
modeled soil concentrations at various distances from the facility (5
soil concentrations x 8 octants = total of 40 soil concentrations per
facility) and 1 lake with modeled concentrations for water, sediment
and fish tissue. In the Tier II environmental risk screening analysis,
the 40 soil concentration points are averaged to obtain an average soil
concentration for each facility for each PB-HAP. For the water,
sediment and fish tissue concentrations, the highest value for each
facility for each pollutant is used. If emission concentrations from a
facility do not exceed the Tier II threshold, the facility passes the
screen, and typically is not evaluated further. If emissions from a
facility exceed the Tier II threshold, the facility does not pass the
screen and, therefore, may have the potential to cause adverse
environmental effects. Such facilities are evaluated further to
investigate factors such as the magnitude and characteristics of the
area of exceedance.
g. Acid Gas Methodology
The environmental screening analysis evaluates the potential
phytotoxicity and reduced productivity of plants due to chronic
exposure to acid gases. The environmental risk screening methodology
for acid gases is a single-tier screen that compares the average off-
site ambient air concentration over the modeling domain to ecological
benchmarks for each of the acid gases. Because air concentrations are
compared directly to the ecological benchmarks, emission-based
thresholds are not calculated for acid gases as they
[[Page 37861]]
are in the ecological risk screening methodology for PB-HAPs.
For purposes of ecological risk screening, the EPA identifies a
potential for adverse environmental effects to plant communities from
exposure to acid gases when the average concentration of the HAP around
a facility exceeds the LOAEL ecological benchmark. In such cases, we
further investigate factors such as the magnitude and characteristics
of the area of exceedance (e.g., land use of exceedance area, size of
exceedance area) to determine if there is an adverse environmental
effect.
For further information on the environmental screening analysis
approach, see the Draft Residual Risk Assessment for the Off-Site Waste
and Recovery Operations Source Category, which is available in the
docket for this action.
7. How did we conduct facility-wide assessments?
To put the source category risks in context, we typically examine
the risks from the entire ``facility,'' where the facility includes all
HAP-emitting operations within a contiguous area and under common
control. In other words, we examine the HAP emissions not only from the
source category emission points of interest, but also emissions of HAP
from all other emission sources at the facility for which we have data.
The emissions data for estimating these ``facility-wide'' risks were
obtained from the 2005 NEI (available at http://www.epa.gov/ttn/atw/nata2005). We analyzed risks due to the inhalation of HAP that are
emitted ``facility-wide'' for the populations residing within 50 km of
each facility, consistent with the methods used for the source category
analysis described above. For these facility-wide risk analyses, the
modeled source category risks were compared to the facility-wide risks
to determine the portion of facility-wide risks that could be
attributed to the source category addressed in this proposal. We
specifically examined the facility that was associated with the highest
estimate of risk and determined the percentage of that risk
attributable to the source category of interest. The Draft Residual
Risk Assessment for the Off-Site Waste and Recovery Operations Source
Category available through the docket for this action provides the
methodology and results of the facility-wide analyses, including all
facility-wide risks and the percentage of source category contribution
to facility-wide risks.
8. How did we consider uncertainties in risk assessment?
In the Benzene NESHAP, we concluded that risk estimation
uncertainty should be considered in our decision-making under the ample
margin of safety framework. Uncertainty and the potential for bias are
inherent in all risk assessments, including those performed for this
proposal. Although uncertainty exists, we believe that our approach,
which used conservative tools and assumptions, ensures that our
decisions are health protective and environmentally protective. A brief
discussion of the uncertainties in the RTR emissions dataset,
dispersion modeling, inhalation exposure estimates and dose-response
relationships follows below. A more thorough discussion of these
uncertainties is included in the Draft Residual Risk Assessment for the
Off-Site Waste and Recovery Operations Source Category, which is
available in the docket for this action.
a. Uncertainties in the RTR Emissions Dataset
Although the development of the RTR emissions dataset involved
quality assurance/quality control processes, the accuracy of emissions
values will vary depending on the source of the data, the degree to
which data are incomplete or missing, the degree to which assumptions
made to complete the datasets are accurate, errors in emission
estimates and other factors. The emission estimates considered in this
analysis generally are annual totals for certain years and they do not
reflect short-term fluctuations during the course of a year or
variations from year to year. The estimates of peak hourly emission
rates for the acute effects screening assessment were based on an
emission adjustment factor applied to the average annual hourly
emission rates, which are intended to account for emission fluctuations
due to normal facility operations.
b. Uncertainties in Dispersion Modeling
We recognize there is uncertainty in ambient concentration
estimates associated with any model, including the EPA's recommended
regulatory dispersion model, AERMOD. In using a model to estimated
ambient pollutant concentrations, the user chooses certain options to
apply. For RTR assessments, we select some model options that have the
potential to overestimate ambient air concentrations (e.g., not
including plume depletion or pollutant transformation). We select other
model options that have the potential to underestimate ambient impacts
(e.g., not including building downwash). Other options that we select
have the potential to either under- or overestimate ambient levels
(e.g., meteorology and receptor locations). On balance, considering the
directional nature of the uncertainties commonly present in ambient
concentrations estimated by dispersion models, the approach we apply in
the RTR assessments should yield unbiased estimates of ambient HAP
concentrations.
c. Uncertainties in Inhalation Exposure
The EPA did not include the effects of human mobility on exposures
in the assessment. Specifically, short-term mobility and long-term
mobility between census blocks in the modeling domain were not
considered.\15\ The approach of not considering short or long-term
population mobility does not bias the estimate of the theoretical MIR
(by definition), nor does it affect the estimate of cancer incidence
because the total population number remains the same. It does, however,
affect the shape of the distribution of individual risks across the
affected population, shifting it toward higher estimated individual
risks at the upper end and reducing the number of people estimated to
be at lower risks, thereby increasing the estimated number of people at
specific high risk levels (e.g., 1-in-10 thousand or 1-in-1 million).
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\15\ Short-term mobility is movement from one micro-environment
to another over the course of hours or days. Long-term mobility is
movement from one residence to another over the course of a
lifetime.
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In addition, the assessment predicted the chronic exposures at the
centroid of each populated census block as surrogates for the exposure
concentrations for all people living in that block. Using the census
block centroid to predict chronic exposures tends to over-predict
exposures for people in the census block who live farther from the
facility and under-predict exposures for people in the census block who
live closer to the facility. Thus, using the census block centroid to
predict chronic exposures may lead to a potential understatement or
overstatement of the true maximum impact, but is an unbiased estimate
of average risk and incidence. We reduce this uncertainty by analyzing
large census blocks near facilities using aerial imagery and adjusting
the location of the block centroid to better represent the population
in the block, as well as adding additional receptor locations where the
block population is not well represented by a single location.
The assessment evaluates the cancer inhalation risks associated
with
[[Page 37862]]
pollutant exposures over a 70-year period, which is the assumed
lifetime of an individual. In reality, both the length of time that
modeled emission sources at facilities actually operate (i.e., more or
less than 70 years) and the domestic growth or decline of the modeled
industry (i.e., the increase or decrease in the number or size of
domestic facilities) will influence the future risks posed by a given
source or source category. Depending on the characteristics of the
industry, these factors will, in most cases, result in an overestimate
both in individual risk levels and in the total estimated number of
cancer cases. However, in the unlikely scenario where a facility
maintains, or even increases, its emissions levels over a period of
more than 70 years, residents live beyond 70 years at the same
location, and the residents spend most of their days at that location,
then the cancer inhalation risks could potentially be underestimated.
However, annual cancer incidence estimates from exposures to emissions
from these sources would not be affected by the length of time an
emissions source operates.
The exposure estimates used in these analyses assume chronic
exposures to ambient (outdoor) levels of pollutants. Because most
people spend the majority of their time indoors, actual exposures may
not be as high, depending on the characteristics of the pollutants
modeled. For many of the HAP, indoor levels are roughly equivalent to
ambient levels, but for very reactive pollutants or larger particles,
indoor levels are typically lower. This factor has the potential to
result in an overestimate of 25 to 30 percent of exposures.\16\
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\16\ U.S. EPA. National-Scale Air Toxics Assessment for 1996.
(EPA 453/R-01-003; January 2001; page 85.)
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In addition to the uncertainties highlighted above, there are
several factors specific to the acute exposure assessment that should
be highlighted. The accuracy of an acute inhalation exposure assessment
depends on the simultaneous occurrence of independent factors that may
vary greatly, such as hourly emissions rates, meteorology and human
activity patterns. In this assessment, we assume that individuals
remain for 1 hour at the point of maximum ambient concentration as
determined by the co-occurrence of peak emissions and worst-case
meteorological conditions. These assumptions would tend to be worst-
case actual exposures as it is unlikely that a person would be located
at the point of maximum exposure when peak emissions and worst-case
meteorological conditions occur simultaneously.
d. Uncertainties in Dose-Response Relationships
There are uncertainties inherent in the development of the dose-
response values used in our risk assessments for cancer effects from
chronic exposures and non-cancer effects from both chronic and acute
exposures. Some uncertainties may be considered quantitatively, and
others generally are expressed in qualitative terms. We note as a
preface to this discussion a point on dose-response uncertainty that is
brought out in the EPA's 2005 Cancer Guidelines; namely, that ``the
primary goal of EPA actions is protection of human health; accordingly,
as an Agency policy, risk assessment procedures, including default
options that are used in the absence of scientific data to the
contrary, should be health protective'' (EPA 2005 Cancer Guidelines,
pages 1-7). This is the approach followed here as summarized in the
next several paragraphs. A complete detailed discussion of
uncertainties and variability in dose-response relationships is given
in the Draft Residual Risk Assessment for the Off-Site Waste and
Recovery Operations Source Category, which is available in the docket
for this action.
Cancer URE values used in our risk assessments are those that have
been developed to generally provide an upper bound estimate of risk.
That is, they represent a ``plausible upper limit to the true value of
a quantity'' (although this is usually not a true statistical
confidence limit).\17\ In some circumstances, the true risk could be as
low as zero; however, in other circumstances the risk could be
greater.\18\ When developing an upper bound estimate of risk and to
provide risk values that do not underestimate risk, health-protective
default approaches are generally used. To err on the side of ensuring
adequate health protection, the EPA typically uses the upper bound
estimates rather than lower bound or central tendency estimates in our
risk assessments, an approach that may have limitations for other uses
(e.g., priority-setting or expected benefits analysis).
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\17\ IRIS glossary (http://www.epa.gov/NCEA/iris/help_gloss.htm).
\18\ An exception to this is the URE for benzene, which is
considered to cover a range of values, each end of which is
considered to be equally plausible, and which is based on maximum
likelihood estimates.
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Chronic non-cancer RfC and reference dose (RfD) values represent
chronic exposure levels that are intended to be health-protective
levels. Specifically, these values provide an estimate (with
uncertainty spanning perhaps an order of magnitude) of a continuous
inhalation exposure (RfC) or a daily oral exposure (RfD) to the human
population (including sensitive subgroups) that is likely to be without
an appreciable risk of deleterious effects during a lifetime. To derive
values that are intended to be ``without appreciable risk,'' the
methodology relies upon an uncertainty factor (UF) approach (U.S. EPA,
1993, 1994) which considers uncertainty, variability and gaps in the
available data. The UF are applied to derive reference values that are
intended to protect against appreciable risk of deleterious effects.
The UF are commonly default values,\19\ e.g., factors of 10 or 3, used
in the absence of compound-specific data; where data are available, UF
may also be developed using compound-specific information. When data
are limited, more assumptions are needed and more UF are used. Thus,
there may be a greater tendency to overestimate risk in the sense that
further study might support development of reference values that are
higher (i.e., less potent) because fewer default assumptions are
needed. However, for some pollutants, it is possible that risks may be
underestimated.
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\19\ According to the NRC report, Science and Judgment in Risk
Assessment (NRC, 1994) ``[Default] options are generic approaches,
based on general scientific knowledge and policy judgment, that are
applied to various elements of the risk assessment process when the
correct scientific model is unknown or uncertain.'' The 1983 NRC
report, Risk Assessment in the Federal Government: Managing the
Process, defined default option as ``the option chosen on the basis
of risk assessment policy that appears to be the best choice in the
absence of data to the contrary'' (NRC, 1983a, p. 63). Therefore,
default options are not rules that bind the Agency; rather, the
Agency may depart from them in evaluating the risks posed by a
specific substance when it believes this to be appropriate. In
keeping with EPA's goal of protecting public health and the
environment, default assumptions are used to ensure that risk to
chemicals is not underestimated (although defaults are not intended
to overtly overestimate risk). See EPA, 2004, An Examination of EPA
Risk Assessment Principles and Practices, EPA/100/B-04/001 available
at: http://www.epa.gov/osa/pdfs/ratf-final.pdf.
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While collectively termed ``UF,'' these factors account for a
number of different quantitative considerations when using observed
animal (usually rodent) or human toxicity data in the development of
the RfC. The UF are intended to account for: (1) Variation in
susceptibility among the members of the human population (i.e., inter-
individual variability); (2) uncertainty in extrapolating from
experimental animal data to humans (i.e., interspecies
[[Page 37863]]
differences); (3) uncertainty in extrapolating from data obtained in a
study with less-than-lifetime exposure (i.e., extrapolating from sub-
chronic to chronic exposure); (4) uncertainty in extrapolating the
observed data to obtain an estimate of the exposure associated with no
adverse effects; and (5) uncertainty when the database is incomplete or
there are problems with the applicability of available studies.
Many of the UF used to account for variability and uncertainty in
the development of acute reference values are quite similar to those
developed for chronic durations, but they more often use individual UF
values that may be less than 10. The UF are applied based on chemical-
specific or health effect-specific information (e.g., simple irritation
effects do not vary appreciably between human individuals, hence a
value of 3 is typically used), or based on the purpose for the
reference value (see the following paragraph). The UF applied in acute
reference value derivation include: (1) Heterogeneity among humans; (2)
uncertainty in extrapolating from animals to humans; (3) uncertainty in
lowest observed adverse effect (exposure) level to no observed adverse
effect (exposure) level adjustments; and (4) uncertainty in accounting
for an incomplete database on toxic effects of potential concern.
Additional adjustments are often applied to account for uncertainty in
extrapolation from observations at one exposure duration (e.g., 4
hours) to derive an acute reference value at another exposure duration
(e.g., 1 hour).
Not all acute reference values are developed for the same purpose
and care must be taken when interpreting the results of an acute
assessment of human health effects relative to the reference value or
values being exceeded. Where relevant to the estimated exposures, the
lack of short-term dose-response values at different levels of severity
should be factored into the risk characterization as potential
uncertainties.
Although every effort is made to identify appropriate human health
effect dose-response assessment values for all pollutants emitted by
the sources in this risk assessment, some HAP emitted by this source
category are lacking dose-response assessments. Accordingly, these
pollutants cannot be included in the quantitative risk assessment,
which could result in quantitative estimates understating HAP risk. To
help to alleviate this potential underestimate, where we conclude
similarity with a HAP for which a dose-response assessment value is
available, we use that value as a surrogate for the assessment of the
HAP for which no value is available. To the extent use of surrogates
indicates appreciable risk, we may identify a need to increase priority
for new IRIS assessment of that substance. We additionally note that,
generally speaking, HAP of greatest concern due to environmental
exposures and hazard are those for which dose-response assessments have
been performed, reducing the likelihood of understating risk. Further,
HAP not included in the quantitative assessment are assessed
qualitatively and considered in the risk characterization that informs
the risk management decisions, including with regard to consideration
of HAP reductions achieved by various control options.
For a group of compounds that are not speciated (e.g., glycol
ethers), we conservatively use the most protective reference value of
an individual compound in that group to estimate risk. Similarly, for
an individual compound in a group (e.g., ethylene glycol diethyl ether)
that does not have a specified reference value, we also apply the most
protective reference value from the other compounds in the group to
estimate risk.
e. Uncertainties in the Multipathway Assessment
For each source category, we generally rely on site-specific levels
of PB-HAP emissions to determine whether a refined assessment of the
impacts from multipathway exposures is necessary. This determination is
based on the results of a two-tiered screening analysis that relies on
the outputs from models that estimate environmental pollutant
concentrations and human exposures for four PB-HAP. Two important types
of uncertainty associated with the use of these models in RTR risk
assessments and inherent to any assessment that relies on environmental
modeling are model uncertainty and input uncertainty.\20\
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\20\ In the context of this discussion, the term ``uncertainty''
as it pertains to exposure and risk encompasses both variability in
the range of expected inputs and screening results due to existing
spatial, temporal, and other factors, as well as uncertainty in
being able to accurately estimate the true result.
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Model uncertainty concerns whether the selected models are
appropriate for the assessment being conducted and whether they
adequately represent the actual processes that might occur for that
situation. An example of model uncertainty is the question of whether
the model adequately describes the movement of a pollutant through the
soil. This type of uncertainty is difficult to quantify. However, based
on feedback received from previous EPA Science Advisory Board reviews
and other reviews, we are confident that the models used in the screen
are appropriate and state-of-the-art for the multipathway risk
assessments conducted in support of RTR.
Input uncertainty is concerned with how accurately the models have
been configured and parameterized for the assessment at hand. For Tier
I of the multipathway screen, we configured the models to avoid
underestimating exposure and risk. This was accomplished by selecting
upper-end values from nationally-representative data sets for the more
influential parameters in the environmental model, including selection
and spatial configuration of the area of interest, lake location and
size, meteorology, surface water and soil characteristics and structure
of the aquatic food web. We also assume an ingestion exposure scenario
and values for human exposure factors that represent reasonable maximum
exposures.
In Tier II of the multipathway assessment, we refine the model
inputs to account for meteorological patterns in the vicinity of the
facility versus using upper-end national values and we identify the
actual location of lakes near the facility rather than the default lake
location that we apply in Tier I. By refining the screening approach in
Tier II to account for local geographical and meteorological data, we
decrease the likelihood that concentrations in environmental media are
overestimated, thereby increasing the usefulness of the screen. The
assumptions and the associated uncertainties regarding the selected
ingestion exposure scenario are the same for Tier I and Tier II.
For both Tiers I and II of the multipathway assessment, our
approach to addressing model input uncertainty is generally cautious.
We choose model inputs from the upper end of the range of possible
values for the influential parameters used in the models, and we assume
that the exposed individual exhibits ingestion behavior that would lead
to a high total exposure. This approach reduces the likelihood of not
identifying high risks for adverse impacts.
Despite the uncertainties, when individual pollutants or facilities
do screen out, we are confident that the potential for adverse
multipathway impacts on human health is very low. On the other hand,
when individual pollutants or facilities do not screen out, it does not
mean that multipathway impacts are significant, only that we cannot
rule out that possibility and that a refined multipathway analysis for
the
[[Page 37864]]
site might be necessary to obtain a more accurate risk characterization
for the source category.
For further information on uncertainties and the Tier I and II
screening methods, refer to the risk document Appendix 4, ``Technical
Support Document for TRIM-Based Multipathway Tiered Screening
Methodology for RTR.''
f. Uncertainties in the Environmental Risk Screening Assessment
For each source category, we generally rely on site-specific levels
of environmental HAP emissions to perform an environmental screening
assessment. The environmental screening assessment is based on the
outputs from models that estimate environmental HAP concentrations. The
same models, specifically the TRIM.FaTE multipathway model and the
AERMOD air dispersion model, are used to estimate environmental HAP
concentrations for both the human multipathway screening analysis and
for the environmental screening analysis. Therefore, both screening
assessments have similar modeling uncertainties.
Two important types of uncertainty associated with the use of these
models in RTR environmental screening assessments--and inherent to any
assessment that relies on environmental modeling--are model uncertainty
and input uncertainty.\21\
---------------------------------------------------------------------------
\21\ In the context of this discussion, the term
``uncertainty,'' as it pertains to exposure and risk assessment,
encompasses both variability in the range of expected inputs and
screening results due to existing spatial, temporal, and other
factors, as well as uncertainty in being able to accurately estimate
the true result.
---------------------------------------------------------------------------
Model uncertainty concerns whether the selected models are
appropriate for the assessment being conducted and whether they
adequately represent the movement and accumulation of environmental HAP
emissions in the environment. For example, does the model adequately
describe the movement of a pollutant through the soil? This type of
uncertainty is difficult to quantify. However, based on feedback
received from previous EPA Science Advisory Board reviews and other
reviews, we are confident that the models used in the screen are
appropriate and state-of-the-art for the environmental risk assessments
conducted in support of our RTR analyses.
Input uncertainty is concerned with how accurately the models have
been configured and parameterized for the assessment at hand. For Tier
I of the environmental screen for PB-HAP, we configured the models to
avoid underestimating exposure and risk to reduce the likelihood that
the results indicate the risks are lower than they actually are. This
was accomplished by selecting upper-end values from nationally-
representative data sets for the more influential parameters in the
environmental model, including selection and spatial configuration of
the area of interest, the location and size of any bodies of water,
meteorology, surface water and soil characteristics and structure of
the aquatic food web. In Tier I, we used the maximum facility-specific
emissions for the PB-HAP (other than lead compounds, which were
evaluated by comparison to the secondary lead NAAQS) that were included
in the environmental screening assessment and each of the media when
comparing to ecological benchmarks. This is consistent with the
conservative design of Tier I of the screen. In Tier II of the
environmental screening analysis for PB-HAP, we refine the model inputs
to account for meteorological patterns in the vicinity of the facility
versus using upper-end national values, and we identify the locations
of water bodies near the facility location. By refining the screening
approach in Tier II to account for local geographical and
meteorological data, we decrease the likelihood that concentrations in
environmental media are overestimated, thereby increasing the
usefulness of the screen. To better represent widespread impacts, the
modeled soil concentrations are averaged in Tier II to obtain one
average soil concentration value for each facility and for each PB-HAP.
For PB-HAP concentrations in water, sediment and fish tissue, the
highest value for each facility for each pollutant is used.
For the environmental screening assessment for acid gases, we
employ a single-tiered approach. We use the modeled air concentrations
and compare those with ecological benchmarks.
For both Tiers I and II of the environmental screening assessment,
our approach to addressing model input uncertainty is generally
cautious. We choose model inputs from the upper end of the range of
possible values for the influential parameters used in the models, and
we assume that the exposed individual exhibits ingestion behavior that
would lead to a high total exposure. This approach reduces the
likelihood of not identifying potential risks for adverse environmental
impacts.
Uncertainty also exists in the ecological benchmarks for the
environmental risk screening analysis. We established a hierarchy of
preferred benchmark sources to allow selection of benchmarks for each
environmental HAP at each ecological assessment endpoint. In general,
EPA benchmarks used at a programmatic level (e.g., Office of Water,
Superfund Program) were used if available. If not, we used EPA
benchmarks used in regional programs (e.g., Superfund Program). If
benchmarks were not available at a programmatic or regional level, we
used benchmarks developed by other agencies (e.g., NOAA) or by state
agencies.
In all cases (except for lead compounds, which were evaluated
through a comparison to the NAAQS), we searched for benchmarks at the
following three effect levels, as described in section III.A.6 of this
preamble:
1. A no-effect level (i.e., NOAEL).
2. Threshold-effect level (i.e., LOAEL).
3. Probable effect level (i.e., PEL).
For some ecological assessment endpoint/environmental HAP
combinations, we could identify benchmarks for all three effect levels,
but for most, we could not. In one case, where different agencies
derived significantly different numbers to represent a threshold for
effect, we included both. In several cases, only a single benchmark was
available. In cases where multiple effect levels were available for a
particular PB-HAP and assessment endpoint, we used all of the available
effect levels to help us to determine whether risk exists and if the
risks could be considered significant and widespread.
The EPA evaluated the following seven HAP in the environmental risk
screening assessment: cadmium, dioxins/furans, POM, mercury (both
inorganic mercury and methyl mercury), lead compounds, HCl and HF.
These seven HAP represent pollutants that can cause adverse impacts for
plants and animals either through direct exposure to HAP in the air or
through exposure to HAP that is deposited from the air onto soils and
surface waters. These seven HAP also represent those HAP for which we
can conduct a meaningful environmental risk screening assessment. For
other HAP not included in our screening assessment, the model has not
been parameterized such that it can be used for that purpose. In some
cases, depending on the HAP, we may not have appropriate multipathway
models that allow us to predict the concentration of that pollutant.
The EPA acknowledges that other HAP beyond the seven HAP that we are
evaluating may have the potential to cause adverse environmental
effects and, therefore, the
[[Page 37865]]
EPA may evaluate other relevant HAP in the future, as modeling science
and resources allow.
Further information on uncertainties and the Tier I and II
environmental screening methods is provided in Appendix 5 of the
document ``Technical Support Document for TRIM-Based Multipathway
Tiered Screening Methodology for RTR: Summary of Approach and
Evaluation.'' Also, see the Draft Residual Risk Assessment for the Off-
Site Waste and Recovery Operations Source Category, available in the
docket for this action.
B. How did we consider the risk results in making decisions for this
proposal?
As discussed in section II.A of this preamble, in evaluating and
developing standards under section 112(f)(2), we apply a two-step
process to address residual risk. In the first step, the EPA determines
whether risks are acceptable. This determination ``considers all health
information, including risk estimation uncertainty, and includes a
presumptive limit on maximum individual lifetime [cancer] risk (MIR)
\22\ of approximately [1-in-10 thousand] [i.e., 100-in-1 million].'' 54
FR 38045, September 14, 1989. If risks are unacceptable, the EPA must
determine the emissions standards necessary to bring risks to an
acceptable level without considering costs. In the second step of the
process, the EPA considers whether the emissions standards provide an
ample margin of safety ``in consideration of all health information,
including the number of persons at risk levels higher than
approximately 1-in-1 million, as well as other relevant factors,
including costs and economic impacts, technological feasibility, and
other factors relevant to each particular decision.'' Id. The EPA must
promulgate tighter emission standards if necessary to provide an ample
margin of safety.
---------------------------------------------------------------------------
\22\ Although defined as ``maximum individual risk,'' MIR refers
only to cancer risk. MIR, one metric for assessing cancer risk, is
the estimated risk were an individual exposed to the maximum level
of a pollutant for a lifetime.
---------------------------------------------------------------------------
In past residual risk actions, the EPA considered a number of human
health risk metrics associated with emissions from the categories under
review, including the MIR, the number of persons in various risk
ranges, cancer incidence, the maximum non-cancer HI and the maximum
acute non-cancer hazard. See, e.g., 72 FR 25138, May 3, 2007; 71 FR
42724, July 27, 2006. The EPA considered this health information for
both actual and MACT-allowable emissions. See, e.g., 75 FR 65068,
October 21, 2010; 75 FR 80220, December 21, 2010; 76 FR 29032, May 19,
2011. The EPA also discussed risk estimation uncertainties and
considered the uncertainties in the determination of acceptable risk
and ample margin of safety in these past actions. The EPA considered
this same type of information in support of this action.
The agency is considering these various measures of health
information to inform our determinations of risk acceptability and
ample margin of safety under CAA section 112(f). As explained in the
Benzene NESHAP, ``the first step judgment on acceptability cannot be
reduced to any single factor'' and thus ``[t]he Administrator believes
that the acceptability of risk under [previous] section 112 is best
judged on the basis of a broad set of health risk measures and
information.'' 54 FR 38046, September 14, 1989. Similarly, with regard
to the ample margin of safety determination, ``the Agency again
considers all of the health risk and other health information
considered in the first step. Beyond that information, additional
factors relating to the appropriate level of control will also be
considered, including cost and economic impacts of controls,
technological feasibility, uncertainties, and any other relevant
factors.'' Id.
The Benzene NESHAP approach provides flexibility regarding factors
the EPA may consider in making determinations and how the EPA may weigh
those factors for each source category. In responding to comment on our
policy under the Benzene NESHAP, the EPA explained that:
``[t]he policy chosen by the Administrator permits consideration
of multiple measures of health risk. Not only can the MIR figure be
considered, but also incidence, the presence of non-cancer health
effects, and the uncertainties of the risk estimates. In this way,
the effect on the most exposed individuals can be reviewed as well
as the impact on the general public. These factors can then be
weighed in each individual case. This approach complies with the
Vinyl Chloride mandate that the Administrator ascertain an
acceptable level of risk to the public by employing [her] expertise
to assess available data. It also complies with the Congressional
intent behind the CAA, which did not exclude the use of any
particular measure of public health risk from the EPA's
consideration with respect to CAA section 112 regulations, and
thereby implicitly permits consideration of any and all measures of
health risk which the Administrator, in [her] judgment, believes are
appropriate to determining what will `protect the public health'.''
See 54 FR at 38057, September 14, 1989. Thus, the level of the MIR is
only one factor to be weighed in determining acceptability of risks.
The Benzene NESHAP explained that ``an MIR of approximately one in 10
thousand should ordinarily be the upper end of the range of
acceptability. As risks increase above this benchmark, they become
presumptively less acceptable under CAA section 112, and would be
weighed with the other health risk measures and information in making
an overall judgment on acceptability. Or, the Agency may find, in a
particular case, that a risk that includes MIR less than the
presumptively acceptable level is unacceptable in the light of other
health risk factors.'' Id. at 38045. Similarly, with regard to the
ample margin of safety analysis, the EPA stated in the Benzene NESHAP
that: ``EPA believes the relative weight of the many factors that can
be considered in selecting an ample margin of safety can only be
determined for each specific source category. This occurs mainly
because technological and economic factors (along with the health-
related factors) vary from source category to source category.'' Id. at
38061. We also consider the uncertainties associated with the various
risk analyses, as discussed earlier in this preamble, in our
determinations of acceptability and ample margin of safety.
The EPA notes that it has not considered certain health information
to date in making residual risk determinations. At this time, we do not
attempt to quantify those HAP risks that may be associated with
emissions from other facilities that do not include the source
categories in question, mobile source emissions, natural source
emissions, persistent environmental pollution or atmospheric
transformation in the vicinity of the sources in these categories.
The agency understands the potential importance of considering an
individual's total exposure to HAP in addition to considering exposure
to HAP emissions from the source category and facility. We recognize
that such consideration may be particularly important when assessing
non-cancer risks, where pollutant-specific exposure health reference
levels (e.g., RfCs) are based on the assumption that thresholds exist
for adverse health effects. For example, the agency recognizes that,
although exposures attributable to emissions from a source category or
facility alone may not indicate the potential for increased risk of
adverse non-cancer health effects in a population, the exposures
resulting from emissions from the facility in combination with
emissions from all of the other sources (e.g., other facilities) to
which an individual is exposed may be sufficient to result in increased
risk of adverse non-cancer health effects. In
[[Page 37866]]
May 2010, the SAB advised the EPA ``that RTR assessments will be most
useful to decision makers and communities if results are presented in
the broader context of aggregate and cumulative risks, including
background concentrations and contributions from other sources in the
area.'' \23\
---------------------------------------------------------------------------
\23\ EPA's responses to this and all other key recommendations
of the SAB's advisory on RTR risk assessment methodologies (which is
available at: http://yosemite.epa.gov/sab/sabproduct.nsf/
4AB3966E263D943A8525771F00668381/$File/EPA-SAB-10-007-unsigned.pdf)
are outlined in a memo in this proposed rule docket from David
Guinnup entitled, EPA's Actions in Response to the Key
Recommendations of the SAB Review of RTR Risk Assessment
Methodologies.
---------------------------------------------------------------------------
In response to the SAB recommendations, the EPA is incorporating
cumulative risk analyses into its RTR risk assessments, including those
reflected in this proposal. The agency is: (1) Conducting facility-wide
assessments, which include source category emission points as well as
other emission points within the facilities; (2) considering sources in
the same category whose emissions result in exposures to the same
individuals; and (3) for some persistent and bioaccumlative pollutants,
analyzing the ingestion route of exposure. In addition, the RTR risk
assessments have always considered aggregate cancer risk from all
carcinogens and aggregate non-cancer hazard indices from all non-
carcinogens affecting the same target organ system.
Although we are interested in placing source category and facility-
wide HAP risks in the context of total HAP risks from all sources
combined in the vicinity of each source, we are concerned about the
uncertainties of doing so. Because of the contribution to total HAP
risk from emission sources other than those that we have studied in
depth during this RTR review (i.e., those sources located at facilities
within the source category), such estimates of total HAP risks would
have significantly greater associated uncertainties than the source
category or facility-wide estimates. Such aggregate or cumulative
assessments would compound those uncertainties, making the assessments
too unreliable.
C. How did we perform the technology review?
Our technology review focused on the identification and evaluation
of developments in practices, processes and control technologies that
have occurred since the MACT standards were promulgated. Where we
identified such developments, in order to inform our decision of
whether it is ``necessary'' to revise the emissions standards, we
analyzed the technical feasibility of applying these developments, and
the estimated costs, energy implications, non-air environmental
impacts, as well as considering the emission reductions. We also
considered the appropriateness of applying controls to new sources
versus retrofitting existing sources.
Based on our analyses of the available data and information, we
identified potential developments in practices, processes and control
technologies. For this exercise, we considered any of the following to
be a ``development'':
Any add-on control technology or other equipment that
was not identified and considered during development of the original
MACT standards.
Any improvements in add-on control technology or other
equipment (that were identified and considered during development of
the original MACT standards) that could result in additional
emissions reduction.
Any work practice or operational procedure that was not
identified or considered during development of the original MACT
standards.
Any process change or pollution prevention alternative
that could be broadly applied to the industry and that was not
identified or considered during development of the original MACT
standards.
Any significant changes in the cost (including cost
effectiveness) of applying controls (including controls the EPA
considered during the development of the original MACT standards).
We reviewed a variety of data sources in our investigation of
potential practices, processes or controls to consider. Among the
sources we reviewed were the NESHAP for various industries that were
promulgated since the MACT standards reviewed in this action. We
reviewed the regulatory requirements and/or technical analyses
associated with these regulatory actions to identify any practices,
processes and control technologies considered in these efforts that
could be applied to emission sources in the OSWRO source category, as
well as the costs, non-air impacts and energy implications associated
with the use of these technologies. Additionally, we requested
information from facilities regarding developments in practices,
processes or control technology. Finally, we reviewed information from
other sources, such as state and/or local permitting agency databases
and industry-supported databases.
IV. Analytical Results and Proposed Decisions
This section of the preamble provides the results of our RTR for
the OSWRO source category and our proposed decisions concerning changes
to the OSWRO NESHAP.
A. What are the results of the risk assessment and analyses?
1. Inhalation Risk Assessment Results
Table 2 of this preamble provides a summary of the results of the
inhalation risk assessment for the source category.
Table 2--Off-Site Waste and Recovery Operations Inhalation Risk Assessment Results
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maximum individual cancer risk (in 1 million) \a\ Maximum chronic non-cancer
------------------------------------------------------ Estimated TOSHI \b\
Estimated population at annual cancer --------------------------------
MACT- increased risk levels of incidence MACT- Maximum screening acute
Actual emissions level allowable cancer (cases per Actual allowable non-cancer HQ \d\
emissions year) emissions emissions
level \c\ level level
--------------------------------------------------------------------------------------------------------------------------------------------------------
9.................................... 20 >= 1-in-1 million: 0.02 0.6 1 HQREL = 1 (glycol
210,000. ethers)
>= 10-in-1 million: 0...
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Estimated maximum individual excess lifetime cancer risk due to HAP emissions from the source category.
\b\ Maximum TOSHI. The target organ with the highest TOSHI for the OSWRO source category for both actual and MACT-allowable emissions is the respiratory
system.
\c\ The development of allowable emission estimates can be found in the memo entitled MACT-Allowable Emissions for the Off-Site Waste and Recovery
Operations Source Category, which is available in the docket for this action.
\d\ The maximum off-site acute value of 1 for actuals is driven by emissions of glycol ethers. See Section III.A.E for an explanation of acute dose-
response values. Acute assessments are not performed with MACT-allowable emissions.
[[Page 37867]]
The inhalation risk modeling performed to estimate risks based on
actual and MACT-allowable emissions relied primarily on data from the
CAA section 114 questionnaire responses and the NEI. The results of the
chronic inhalation cancer risk assessment indicate that, based on
estimates of current actual emissions, the maximum lifetime individual
cancer risk posed by the OSWRO source category is 9-in-1 million, with
emissions of benzidine and 2,4-toluene diamine accounting for the
majority of the risk. The total estimated cancer incidence from the
OSWRO source category based on the actual emissions levels is 0.02
excess cancer cases per year, or one case every 50 years, with
emissions of benzidine and 2,4-toluene diamine contributing to the
majority of the incidence. In addition, we note that approximately
210,000 people are estimated to have cancer risks greater than or equal
to 1-in-1 million as a result of actual emissions from this source
category. When considering MACT-allowable emissions, the maximum
individual lifetime cancer risk is estimated to be up to 20-in-1
million, driven by emissions of benzidine and 2,4-toluene diamine. Due
to the way MACT-allowable risks were calculated, estimates of
population exposure and cancer incidence are not available, but would
be greater than those estimates presented based on actual emissions.
However, since the MIR based on MACT-allowable emissions is 20-in-1
million, there are no people exposed to cancer risks greater than 100-
in-1 million.
The maximum modeled chronic non-cancer TOSHI value for the OSWRO
source category based on actual emissions was estimated to be 0.6, with
emissions of chlorine contributing to the majority of the TOSHI. There
are no people estimated to have exposure to TOSHI levels greater than 1
as a result of actual emissions from this source category. When
considering MACT-allowable emissions, the maximum chronic non-cancer
TOSHI value was estimated to be up to 1, driven by emissions of
chlorine. There are no people estimated to have exposure to TOSHI
levels greater than 1 as a result of emissions at the MACT-allowable
levels from this source category.
Our screening analysis for worst-case acute impacts based on actual
emissions indicates that an HQ value of 1 is not exceeded for any
pollutants at any facility, indicating that the HAP emissions are
believed to be without appreciable risk of acute health effects. In
characterizing the potential for acute non-cancer risks of concern, it
is important to remember the upward bias of these exposure estimates
(e.g., worst-case meteorology coinciding with a person located at the
point of maximum concentration during the hour) and to consider the
results along with the conservative estimates used to develop peak
hourly emissions as described earlier. Refer to Appendix 6 of the Draft
Residual Risk Assessment for the Off-Site Waste and Recovery Operations
Source Category in the docket for this action for the detailed acute
risk results.
2. Multipathway Risk Screening Results
Multiple facilities reported emissions of PB-HAP, including 2-
acetylaminofluorene (a POM compound), heptachlor, and trifluralin. Only
one facility reported emissions of a PB-HAP that has an available RTR
multipathway screening value: 2-acetylaminofluorene, a polycylic
organic matter (POM) compound that was analyzed as benzo(a)pyrene TEQ.
Reported emissions of the POM 2-acetylaminofluorene are below the
multipathway screening level for this compound, indicating low
potential for multipathway risks as a result of emissions of this PB-
HAP. The remaining PB-HAP do not currently have RTR multipathway
screening values, and they were not evaluated for potential non-
inhalation risks. These HAP, however, are not emitted in appreciable
quantities from OSWRO facilities. (For more information on PB-HAP
emitted from this source category, please see the Draft Residual Risk
Assessment for the Off-Site Waste and Recovery Operations Source
Category document available in the docket for this action.)
3. Environmental Risk Screening Results
As described in section III.A.5, we conducted an environmental risk
screening assessment for the OSWRO source category. Emissions of three
environmental HAP were reported by OSWRO facilities: POM, hydrogen
chloride and hydrogen fluoride. For POM, none of the individual modeled
concentrations for any facility in the source category exceeded any of
the ecological benchmarks (either the LOAEL or NOAEL). For the acid
gases HCl and HF, the average modeled concentration of these chemicals
around each facility (i.e., the average concentration of all off-
facility-site data points in the modeling domain) did not exceed any
ecological benchmarks. In addition, each individual modeled
concentration of hydrogen chloride and hydrogen fluoride (i.e., each
off-facility-site data point in the modeling domain) was below the
ecological benchmarks for all facilities.
4. Facility-wide Inhalation Risk Assessment Results
Table 3 displays the results of the facility-wide risk assessment.
This assessment is based on actual emission levels. For detailed
facility-specific results, see Appendix 5 of the Draft Residual Risk
Assessment for the Off-Site Waste and Recovery Operations Source
Category in the docket for this proposed rule.
Table 3--Off-Site Waste and Recovery Operations Facility-Wide Risk
Assessment Results
------------------------------------------------------------------------
------------------------------------------------------------------------
Number of facilities analyzed........................ 38
Cancer Risk:
Estimated maximum facility-wide individual cancer 200
risk (in 1 million).............................
Number of facilities with estimated facility-wide 1
individual cancer risk of 100-in-1 million or
more............................................
Number of facilities at which the OSWRO source 0
category contributes 50 percent or more to the
facility-wide individual cancer risks of 100-in-
1 million or more...............................
Number of facilities with estimated facility-wide 17
individual cancer risk of 1-in-1 million or more
Number of facilities at which the OSWRO source 7
category contributes 50 percent or more to the
facility-wide individual cancer risk of 1-in-1
million or more.................................
Chronic Non-cancer Risk:
Maximum facility-wide chronic non-cancer TOSHI... 4
Number of facilities with facility-wide maximum 2
non-cancer TOSHI greater than 1.................
Number of facilities at which the OSWRO source 0
category contributes 50 percent or more to the
facility-wide maximum non-cancer TOSHI of 1 or
more............................................
------------------------------------------------------------------------
[[Page 37868]]
The facility-wide MIR and TOSHI are based on actual emissions from
all emissions sources at the identified OSWRO facilities. The results
indicate that 17 facilities have a facility-wide cancer MIR greater
than or equal to 1-in-1 million and one facility has a facility-wide
cancer MIR greater than or equal to 100-in-1 million. The maximum
facility-wide MIR is 200-in-1 million due to emissions of beryllium
compounds from the cement manufacturing processes at the facility site,
with emission points from the OSWRO production source category
contributing less than 1 percent of the maximum facility-wide risk. The
results indicate that two facilities have a facility-wide non-cancer
TOSHI greater than or equal to 1. The maximum facility-wide TOSHI is 4,
and this TOSHI occurs at two facilities. At one of these facilities,
the TOSHI is driven mainly by emissions of beryllium compounds from the
same cement manufacturing processes mentioned above. The TOSHI at the
other facility is driven mainly by emissions of chlorine from
industrial inorganic chemical manufacturing processes and synthetic
organic chemical manufacturing processes at the facility site. In each
instance, the OSWRO production source category contributes less than 1
percent to the facility-wide TOSHI. The focus of this analysis is the
OSWRO source category and its low relative contribution to facility-
wide risk. The maximum facility-wide MIR and TOSHI values presented
here are the result of a screening analysis for the other source
categories located at common facility sites. The screening analysis
requires further refinement and takes place during the RTR review for
those source categories. We anticipate reductions of HAP from the
cement manufacturing processes due to the implementation of the
recently promulgated MACT standard, with a compliance date of September
9, 2015, and the upcoming RTR review, with a consent decree deadline of
June 15, 2017 for proposal and June 15, 2018 for promulgation. We may
consider options for achieving further reduction of HAP from the
inorganic chemical and synthetic organic chemical manufacturing
processes in future reviews for those source categories.
5. What demographic groups might benefit from this regulation?
To determine whether or not to conduct a demographics analysis,
which is an assessment of risks to individual demographic groups, we
look at a combination of factors including the MIR, non-cancer TOSHI,
population around the facilities in the source category, and other
relevant factors. Actual emissions from the OSWRO source category
result in no individuals being exposed to cancer risk greater than 9-
in-1 million or a non-cancer TOSHI greater than 1. In addition, we
estimate the cancer incidence for the source category to be 0.02 cases
per year. Therefore, we did not conduct an assessment of risks to
individual demographic groups for this proposed rule. However, we did
conduct a proximity analysis, which identifies any overrepresentation
of minority, low income or indigenous populations near facilities in
the source category. The results of this analysis are presented in the
section of this preamble entitled ``Executive Order 12898: Federal
Actions to Address Environmental Justice in Minority Populations and
Low-Income Populations.''
B. What are our proposed decisions regarding risk acceptability, ample
margin of safety and adverse environmental effects?
1. Risk Acceptability
As discussed in sections II.A and III.B of this preamble, we weigh
all health risk factors in our risk acceptability determination,
including the cancer MIR; the number of persons in various cancer and
non-cancer risk ranges; cancer incidence; the maximum non-cancer TOSHI;
the maximum acute non-cancer HQ; the extent of non-cancer risks; the
potential for adverse environmental effects; the distribution of cancer
and non-cancer risks in the exposed population; and risk estimation
uncertainties (54 FR 38044, September 14, 1989).
For the OSWRO source category, the risk analysis we performed
indicates that the cancer risks to the individual most exposed could be
up to 9-in-1 million due to actual emissions and up to 20-in-1 million
due to MACT-allowable emissions. These risks are considerably less than
100-in-1 million, which is the presumptive upper limit of acceptable
risk. The risk analysis also shows relatively low cancer incidence
(0.02 cases per year), as well as no appreciable risk of deleterious
chronic or acute non-cancer health effects. In addition, the risk
assessment indicates no significant potential multipathway health
effects.
While our analysis of facility-wide risks shows one facility with a
maximum facility-wide cancer risk of 100-in-1 million or greater and
two facilities with a maximum chronic non-cancer TOSHI greater than 1,
it also shows that OSWRO operations did not drive these risks. In fact,
OSWRO operations contribute less than 1 percent to the cancer MIR and
less than 1 percent to the non-cancer TOSHI).
Considering all of the health risk information and factors
discussed above, including the uncertainties discussed in section
III.A.8 of this preamble, we propose that the risks from the OSWRO
source category are acceptable.
2. Ample Margin of Safety Analyses and Proposed Controls
Although we are proposing that the risks from the OSWRO source
category are acceptable, risk estimates for 210,000 individuals in the
exposed population are above 1-in-1 million based on actual emissions.
We recognize that our risk analysis indicates that the cancer risks to
the individual most exposed are well within EPA's acceptable range
(i.e., up to 9-in-1 million due to actual emissions and up to 20-in-1
million due to MACT-allowable emissions). However, as stated in the
Benzene NESHAP, in protecting public health with an ample margin of
safety, ``EPA strives to provide maximum feasible protection against
risks to health from HAP,'' considering available health information,
the incremental risk reduction associated with more stringent
standards, technological feasibility, and other factors, such as costs
and economic impacts of controls. 54 FR at 38044-38045. Consequently,
in this analysis, we investigated available emissions control options
that might reduce the risk associated with emissions from the source
category. We considered this information along with all of the health
risks and other health information considered in determining risk
acceptability. As explained below, we are proposing additional control
requirements for equipment leaks and certain tanks because considering
costs and other factors, we have determined that these additional
controls are capable of further reducing risks to the individual most
exposed, and thus, they provide an ample margin of safety.
For the OSWRO source category, we did not identify any options that
would reduce HAP emissions from containers, surface impoundments, oil-
water separators, organic-water separators or transfer systems beyond
what is currently required in the rule. For process vents, tanks and
equipment leaks, we identified additional control options, which are
described below.
For 19 of the 38 facilities included in the OSWRO risk analysis,
the available data (see discussion of emissions data in section III.A
of this preamble) did not,
[[Page 37869]]
in general, attribute OSWRO emissions to specific emission sources. For
example, the NEI data for many of these facilities grouped emissions
under source classification codes (SCC) for non-specific processes,
such as 39999999--Miscellaneous Industrial Processes. For these
facilities, we lack information as to which processes and emission
point types are contributing to the risk estimates developed in the
risk assessment. In contrast, CAA section 114 response data for the
other 19 facilities were available, and the emissions data for these
facilities were attributed to specific emission point types. However,
the maximum cancer MIR and noncancer TOSHI values for the OSWRO source
category are attributed to a facility for which only NEI data are
available and for which we lack information regarding the processes and
emission point types that contribute to these maximum risk values.
Because we were unable to precisely determine the magnitude of HAP
emissions from specific process types and how those emissions relate to
the risk estimates, we conservatively assumed that the type of
equipment under investigation was responsible for the maximum risks.
For example, in our assessment of process vents, we assumed the maximum
risks for the OSWRO source category were due to process vents, and then
we evaluated how further controls might reduce this risk. While these
assumptions may introduce some uncertainty regarding the risk
reductions that would be achieved for each equipment type, we are
presenting our analysis using the best information available. As noted
in section VI of this preamble, we are requesting commenters to provide
any site-specific emissions or other data that would enable us to
better characterize the maximum risks and the risk reductions from the
proposed control options for the OSWRO source category.
In the ample margin of safety analysis, factors related to the
appropriate level of control are considered, including the costs and
economic impacts of the controls. For the OSWRO source category, the
control options identified to reduce risks are the same as those
identified in the technology review. As such, we relied on the control
cost estimates and estimates of control cost effectiveness derived from
the technology review analyses in our ample margin of safety
determination. We believe that our ample margin of safety analysis is
reasonable. However, we note that if we had data to more precisely
assign HAP emissions to particular emission sources in the risk
modeling file and if that data were to lead us to conclude that the
MACT standards reflect an ample margin of safety, we are still
proposing these same control options under the technology review
because they are technologically applicable and cost effective for this
source category based on our experience with similar emission sources
emitting similar HAP at other chemical type facilities. We request
comments on the proposed controls discussed below to provide an ample
margin of safety for this source category.
For process vents, as discussed in section IV.C of this preamble,
we identified an emissions control option of requiring compliance with
a 98 percent reduction rather than a 95 percent reduction in HAP
emissions. To assess the maximum potential for risk reduction that
could result from this process vent control option, we assumed that the
maximum risks for the OSWRO source category are due to emissions from a
process vent with emissions controlled at 95 percent. In this scenario,
we estimate the HAP reduction resulting from compliance with a 98
percent reduction would be 10 tpy from the current emissions level,
with a cost effectiveness of $350,000/ton HAP reduction. We estimate
this option would reduce the MIR at the MACT-allowable emissions level
for the source category from 20-in-1 million to 8-in-1 million and
reduce the maximum chronic non-cancer TOSHI from 1 to 0.4. Considering
all of the health risks and other health information considered in our
determination of risk acceptability, the potential for reductions in
HAP emissions and risk, the uncertainty associated with the estimated
potential risk reductions and the costs associated with this option, we
are proposing that no additional HAP emissions controls for OSWRO
process vents are necessary to provide an ample margin of safety to
protect public health.
For tanks, as discussed in section IV.C of this preamble, we
identified two emissions control options. Option 1 requires Level 2
control of emissions for additional tanks containing liquids with lower
vapor pressures. Option 2 requires compliance with a 98 percent
reduction rather than a 95 percent reduction in HAP emissions from
tanks. As discussed above for process vents, to assess the maximum
potential for risk reduction that could result from these two tank
control options, we have assumed that the maximum risks for the OSWRO
source category are due to emissions from tanks. For Option 1, we have
assumed that the maximum risks are due to tanks that are not currently
subject to Level 2 controls, which require a 95 percent reduction in
emissions. In this scenario, we estimate the HAP reduction resulting
from compliance with the control of additional tanks would be 73 tpy
from the current emissions level, with a cost effectiveness of $300/ton
HAP reduction. We estimate this option would reduce the MIR at the
MACT-allowable emissions level for the source category from 20-in-1
million to 1-in-1 million and reduce the maximum chronic non-cancer
TOSHI from 1 to 0.05. Under Option 2, we estimate the HAP reduction
incremental to Option 1 would be approximately 22 tpy, with a cost
effectiveness of $13,000/ton HAP reduction and a cost effectiveness
incremental to Option 1 of $56,000/ton HAP reduction. We estimate this
option would reduce the MIR at the MACT-allowable emissions level
incremental to Option 1 for the source category from 1-in-1 million to
0.4-in-1 million and reduce the maximum chronic non-cancer TOSHI from
0.05 to 0.02. Considering all of the health risks and other health
information considered in our determination of risk acceptability, the
potential risk reductions and the costs associated with Option 1, we
are proposing to require this additional level of control to provide an
ample margin of safety. Considering all of the health risks and other
health information considered in our determination of risk
acceptability, the potential for reductions in risk, the uncertainty
associated with the estimated potential risk reductions and the costs
associated with Option 2, we are proposing that the additional HAP
emissions controls for OSWRO tanks under Option 2 are not necessary to
provide an ample margin of safety to protect public health. In
addition, as discussed further in preamble section IV.C, we are also
proposing the Option 1 additional control level as a result of the
technology review.
For equipment leaks, as discussed in section IV.C of this preamble,
we identified two emission control options: Option 1 requires
compliance with 40 CFR part 63, subpart H, rather than 40 CFR part 61,
subpart V, without the connector leak detection and repair (LDAR)
requirements of subpart H; Option 2 requires the same as Option 1 but
includes the connector LDAR requirement of subpart H. As discussed
above for tanks, to assess the maximum potential for risk reduction
that could result from these equipment leaks control options, we
assumed that the maximum risks for the OSWRO source category are due to
emissions from equipment leaks. We also assumed that
[[Page 37870]]
since emissions from equipment leaks are estimated to be the same at
actual and MACT-allowable emission levels, the risks due to equipment
leaks at the MACT-allowable level are the same as risks due to
equipment leaks at actual emissions levels. We additionally assumed,
based on our analysis of estimated baseline equipment leak
emissions,\24\ that half of the equipment leak emissions causing the
maximum risks are from non-connector components (i.e. pumps and
valves), and the other half are from connectors. Given these
assumptions, under Option 1, we estimate the HAP reduction resulting
from compliance with subpart H without the subpart H connector
monitoring requirements would be 69 tpy from the baseline actual
emissions level, with a cost effectiveness of $1,000/ton HAP reduction.
We estimate this option would reduce the MIR at the MACT-allowable
emissions level for the equipment leaks at the source category from 9-
in-1 million to 7-in-1 million and reduce the maximum chronic non-
cancer TOSHI from 0.6 to 0.5. Under Option 2, we estimate the
incremental HAP reduction resulting from compliance with subpart H
including the subpart H connector monitoring requirements would be 70
tpy more than Option 1, with an overall cost effectiveness of $4,000/
ton HAP reduction and a cost effectiveness incremental to Option 1 of
$7,000/ton HAP reduction. We estimate this option would reduce the MIR
at the MACT-allowable emissions level incremental to Option 1 for the
equipment leaks at the source category from 7-in-1 million to 5-in-1
million and reduce the maximum chronic non-cancer TOSHI from 0.5 to
0.3. We note, as discussed in preamble section IV.C, we are proposing
the additional control level of Option 2 as a result of the technology
review. Considering the health risks and other health information
evaluated in our determination of risk acceptability, that some risk
reduction occurs with Option 2, and the costs associated with Option 2
are reasonable, we are proposing to require this additional level of
control to provide an ample margin of safety.
---------------------------------------------------------------------------
\24\ See Technology Review and Cost Impacts for the Proposed
Amendments to the Off-Site Waste and Recovery Operations Source
Category, which is available in the docket for this action.
---------------------------------------------------------------------------
In accordance with the approach established in the Benzene NESHAP,
the EPA weighed all health risk measures and information considered in
the risk acceptability determination, along with the costs of emissions
controls, technological feasibility, uncertainties and other relevant
factors in making our ample margin of safety determination. Considering
the health risk information, the potential risk reductions and the
reasonable cost effectiveness of certain control options identified for
tanks and equipment leaks, we propose that the standards for the OSWRO
source category be revised to include the proposed control Option 1 for
tanks and the proposed control Option 2 for equipment leaks to provide
an ample margin of safety to protect public health.
3. Adverse Environmental Effects
We conducted an environmental risk screening assessment for the
OSWRO source category for POM, HCl and HF. For POM, none of the
individual modeled Tier I concentrations for any facility in the source
category exceeded any of the ecological benchmarks (either the LOAEL or
NOAEL). For HF and HCl, the average modeled concentration around each
facility (i.e., the average concentration of all off-site data points
in the modeling domain) did not exceed any ecological benchmark. Based
on these results, we are proposing that it is not necessary to set a
more stringent standard to prevent such an adverse environmental
effect, taking into consideration costs, energy, safety, and other
relevant factors.
C. What are the results of the technology review and our proposed
decisions?
As described in section III.C of this preamble, our technology
review focused on identifying developments in practices, processes and
control technologies for the emission sources in the OSWRO production
source category. To identify such developments since the MACT standards
were developed, we consulted the EPA's RACT/BACT/LAER Clearinghouse,
reviewed subsequent regulatory development efforts and reviewed data
from the 2013 CAA Section 114 survey of OSWRO facilities. For the OSWRO
source category, we did not identify any developments in practices,
processes or control technologies for containers, surface impoundments,
oil-water separators, organic-water separators or transfer systems
beyond what is currently required in the rule. For process vents, tanks
and equipment leaks, we identified additional control options, and the
following sections summarize the results of our technology review for
these emissions sources.
To perform the technology review, we needed information that was
not included in the RTR emissions dataset used for modeling OSWRO
risks. Therefore, to evaluate the costs and cost-effectiveness of
various control options, we used a model plant approach. The model
plant approach we used resulted in different baseline emission
estimates than those included in the risk modeling dataset. More
information concerning our technology review and model plant approach
can be found in the memorandum titled, Technology Review and Cost
Impacts for the Proposed Amendments to the Off-Site Waste and Recovery
Operations Source Category, which is available in the docket for this
action.
1. Tanks
For tanks at existing affected sources, we identified two potential
developments in practices and control techniques. The current OSWRO
MACT requirements at 40 CFR 63.685(b)(1) for tanks at an existing
affected source depend on the capacity of the tank and the vapor
pressure of the material being stored. ``Level 2'' control is required
for: (1) Tanks with capacities greater than or equal to 75 cubic meters
(m\3\), but less than 151 m\3\ and a vapor pressure of 27.6 kilopascals
(kPa) or greater and (2) tanks with capacities greater than or equal to
151 m\3\ and a vapor pressure of 5.2 kPa or greater. ``Level 2''
control essentially requires one of five options: (1) A fixed roof tank
equipped with an internal floating roof; (2) a fixed roof tank equipped
with an external floating roof; (3) a tank with a vapor-tight cover and
vented through a closed-vent system to a control device that has an
efficiency of 95 percent or more; (4) a pressure tank; or (5) a tank
inside a permanent total enclosure (PTE) that is vented through a
closed-vent system to an enclosed combustion control device. Tanks of
any capacity (effectively those less than 75 m\3\) with a vapor
pressure of 76.6 kPa or greater are required to use one of the options
listed above for Level 2 control, except that fixed roof tanks with
either an internal or an external floating roof cannot be used. For
tanks with capacities and vapor pressures less than those stated above,
``Level 1'' control is required. ``Level 1'' control generally requires
a fixed roof with closure devices.
We evaluated two control options that would change the tank
requirements if adopted. Option 1 would lower the vapor pressure
threshold above which Level 2 controls would be required for some
tanks. Option 2 would revise the vapor pressure threshold as in Option
1 and increase the required control efficiency from the current 95
percent to a 98 percent emissions reduction for all tanks required to
use Level 2 controls. Through the review of air toxics MACT standards
developed subsequent to the
[[Page 37871]]
OSWRO MACT standards, we noted that several other MACT standards refer
to the Hazardous Organic NESHAP (HON) for their storage tank
requirements. We evaluated revising the applicability of the OSWRO
existing source requirements to use the same thresholds for Level 2
control as the thresholds for control required by the HON. As shown in
Table 4, Option 1 would require Level 2 emissions control for tanks
with capacities greater than or equal to 75 m\3\, but less than 151
m\3\, if the vapor pressure of the stored material is 13 kPa or
greater, instead of 27.6 kPa or greater as required by the current MACT
standard. No other tank size or vapor thresholds would be changed with
Option 1. For tanks at new affected sources, the current OSWRO
applicability thresholds are consistent with those required for the
chemical industry under other NESHAP, including the HON, so no revised
applicability requirements were evaluated for tanks located at new
sources.
Because available data for the source category indicate most OSWRO
tanks currently have fixed-roofs with emissions routed through a closed
vent system to a control device, under Option 2 we considered the
impacts of requiring a higher control efficiency than currently
required by the OSWRO MACT standard. While carbon adsorption and other
control devices are assumed to have a control efficiency of 95 percent,
other technologies are capable of achieving greater emissions control,
such as thermal incinerators. Several of these devices have been
demonstrated to achieve a control efficiency of 98 percent or greater.
Under Option 2, we considered the impacts of requiring a 98 percent
emissions reduction for tanks meeting the lowered vapor pressure
threshold under Option 1, and all other tanks required to use Level 2
emission controls, assuming a recuperative thermal oxidizer (RCO) would
be used to attain this increased level of control.
Table 5 presents the emission reductions and costs of the two
options considered for tanks at existing affected sources in the OSWRO
source category under the technology review. For Option 1, data
collected through our CAA section 114 questionnaire indicate that only
some facilities have tanks in the size and vapor pressure range
considered for this option, and based on these data we estimate that
approximately three OSWRO facilities have tanks that would require
additional control under Option 1. As seen in Table 5, for Option 1, we
estimate the capital costs to be approximately $76,000, and the total
annualized costs are estimated to be approximately $21,000. The
estimated HAP emissions reduction is approximately 73 tpy, and the cost
effectiveness is approximately $300/ton. For Option 2, data collected
through our CAA section 114 questionnaire indicate that only some
facilities have tanks that currently require Level 2 emissions controls
or that would require Level 2 control with the revised vapor pressure
threshold of Option 1, and based on this data we estimate that
approximately 10 OSWRO facilities have tanks that would require
additional control under Option 2. We estimate the capital costs to be
approximately $2.8 million, and the total annualized costs are
estimated to be approximately $1.3 million. The estimated HAP emissions
reduction incremental to Option 1 is approximately 22 tpy, and the
incremental cost effectiveness between Option 1 and Option 2 is
approximately $56,000/ton.
Table 4--Requirements of Tank Options 1 and 2 for Existing OSWRO Affected Sources
----------------------------------------------------------------------------------------------------------------
Options 1 and 2 applicability thresholds
--------------------------------------------------- Then control
And vapor level for Option 1 Requirements Option 2 Requirements
If size (m\3\) is pressure (kPa) options 1 and
is 2
----------------------------------------------------------------------------------------------------------------
<75............................... <76.6 1 Fixed roof.
-----------------------------------------------------------------------------
>=76.6 \a\ 2 95% control \b\...... 98% control.\b\
----------------------------------------------------------------------------------------------------------------
75 <= capacity < 151.............. <13.1 1 Fixed roof.
-----------------------------------------------------------------------------
>=13.1 2 95% control \c\...... 98% control.\c\
----------------------------------------------------------------------------------------------------------------
151 <= capacity................... <5.2 1 Fixed roof.
-----------------------------------------------------------------------------
>=5.2 2 95% control \c\...... 98% control.\c\
----------------------------------------------------------------------------------------------------------------
\a\ Except that fixed roof tanks equipped with an internal floating roof and tanks equipped with an external
floating roof shall not be used.
\b\ Control efficiency would apply to tanks vented through a closed vent system to a control device and tanks
inside a PTE that are vented to a combustion control device; use of a pressure tank would still be an
available control option.
\c\ Control efficiency would apply to tanks vented through a closed vent system to a control device and tanks
inside a PTE that are vented to a combustion control device; use of an internal or external floating roof or a
pressure tank would still be available control options.
Table 5--Nationwide Emissions Reductions and Costs of Control Options for Tanks at OSWRO Facilities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Cost
HAP emissions Annual cost ($/ effectiveness Incremental cost
Regulatory options reduction (tpy) Capital cost ($) yr) ($/ton HAP effectiveness ($/
removed) ton HAP removed)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Option 1...................................................... 72.8 76,000 21,000 300 ................
Option 2...................................................... 95.0 2,800,000 1,300,000 13,000 56,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
Based on our analysis, the costs of Option 1 are reasonable, given
the level of HAP emissions reduction that would be achieved with this
control option. The costs of Option 2 do not appear reasonable, given
the level of HAP emissions reduction it would achieve. Therefore, as a
result of the technology review, we are proposing to revise the
[[Page 37872]]
OSWRO MACT standards in accordance with Option 1, i.e., to require
Level 2 controls for tanks at existing affected sources with capacities
greater than or equal to 75 m\3\, but less than 151 m\3\, and a vapor
pressure of 13.1 kPa or greater. We solicit comment on our assessment
and conclusions regarding all aspects of both options. As noted in
section IV.B.2, we are concurrently proposing to revise the OSWRO MACT
standards for existing affected sources to require Level 2 controls for
these tanks under section 112(f)(2) of the CAA to provide an ample
margin of safety to protect public health.
2. Equipment Leaks
The OSWRO MACT standards at 40 CFR 63.691 currently require
compliance with either 40 CFR part 61, subpart V, or 40 CFR part 63,
subpart H, to control emissions from equipment leaks at existing and
new affected sources. While many provisions of these two rules are the
same or similar, subpart H requires the use of a more stringent leak
definition for valves in gas and vapor service and in light liquid
service, pumps in light liquid service, and connectors. Specifically,
subpart H lowers the leak definition for valves from 10,000 ppm (in
subpart V) to 500 ppm, lowers the leak definition for pump seals from
10,000 ppm (in subpart V) to 1,000 ppm, and requires periodic
instrument monitoring of connectors with a leak definition of 500 ppm,
as opposed to instrument monitoring only being required if a potential
leak is detected by visual, audible, olfactory, or other detection
method (in subpart V). We identified the more stringent leak
definitions of subpart H as a development in practices, processes or
control technologies.
Assuming conservatively that each of the OSWRO facilities currently
comply with subpart V and do not already comply with subpart H, we
analyzed the costs and emission reductions of two options: Option 1--
switching from a subpart V LDAR program to a subpart H LDAR program,
without the subpart H connector monitoring requirements; Option 2--
switching from a subpart V LDAR program to a subpart H LDAR program,
with the subpart H connector monitoring requirements. The estimated
costs and emissions reductions associated with these two options for
the OSWRO source category are shown in Table 6. For Option 1 (subpart H
without connector monitoring), we estimated the capital costs to be
approximately $320,000, and the total annualized costs are estimated to
be approximately $67,000. The estimated HAP emissions reduction is
approximately 69 tpy, and the cost effectiveness is approximately
$1,000/ton. For Option 2 (subpart H with connector monitoring), we
estimated the capital costs to be approximately $1,900,000, and the
total annualized costs are estimated to be approximately $530,000. The
estimated HAP emissions reduction is approximately 138 tpy, and the
cost effectiveness is approximately $4,000/ton. The incremental cost
effectiveness between Option 1 and Option 2 is approximately $7,000.
Table 6--OSWRO Equipment Leak Options Emission Reductions and Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Cost Incremental cost
Regulatory alternatives HAP Emissions Capital cost ($) Annual cost ($/ effectiveness ($/ effectiveness ($/
reduction (tpy) yr) ton HAP removed) ton HAP removed)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Option 1: Subpart H, no connector monitoring.................. 68.5 320,000 67,000 1,000 ................
Option 2: Subpart H with connector monitoring................. 138.1 1,900,000 530,000 4,000 7,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
Based on our analysis, the costs of Option 2, which includes all of
the requirements of Option 1, are reasonable, given the level of HAP
emissions reduction that would be achieved with this control option.
Therefore, as a result of the technology review, we are proposing to
revise the OSWRO MACT standards, in accordance with Option 2, to
require existing and new affected sources to comply with subpart H
rather than subpart V, including the subpart H requirements for
connectors in gas and vapor service and in light liquid service. As
noted in section IV.B.2, we are concurrently proposing to revise the
OSWRO MACT standards for existing and new affected sources to require
compliance with subpart H rather than subpart V, including the subpart
H requirements for connectors in gas and vapor service and in light
liquid service under section 112(f)(2) of the CAA to provide an ample
margin of safety to protect public health. We solicit comment on our
assessment and conclusions regarding all aspects of both options.
3. Process Vents
The current OSWRO MACT standards at 40 CFR 63.690 require emissions
from process vents at existing and new affected sources to be routed
through a closed vent system to a control device achieving at least 95
percent control. As discussed above for tanks, while carbon adsorption
and other control devices are assumed to have a control efficiency of
95 percent, other technologies are capable of achieving greater
emissions control, such as thermal incinerators. Several of these
devices have been demonstrated to achieve a control efficiency of 98
percent or greater. Based on the combination of reported control
efficiencies for these devices and known application to low
concentration organic vapor gas streams, we investigated the use of a
regenerative thermal oxidizer with a control efficiency of 98 percent
as a potential control option.
Table 7 presents the emission reductions and costs of the 98
percent control options considered for process vents at existing
affected sources in the OSWRO source category under the technology
review. Data collected through our CAA section 114 questionnaire
indicate that only some facilities have process vents, and based on
these data we estimate that approximately eight OSWRO facilities have
process vents that would require additional control to reduce emissions
by 98 percent. We estimated the capital costs of complying with an
increase from 95 to 98 percent HAP control for process vents to be
approximately $9.8 million, and the total annualized costs are
estimated to be approximately $3.3 million. The estimated HAP emissions
reduction is approximately 10 tpy, and the cost effectiveness is
approximately $350,000/ton of HAP emission reduction.
[[Page 37873]]
Table 7--OSWRO Process Vent Option Impacts
----------------------------------------------------------------------------------------------------------------
Cost
Regulatory option HAP emissions Capital cost ($) Annual cost ($/ effectiveness ($/
reduction (tpy) yr) ton HAP removed)
----------------------------------------------------------------------------------------------------------------
98 percent control.................. 9.6 9,800,000 3,300,000 350,000
----------------------------------------------------------------------------------------------------------------
Based on our estimate of costs and HAP reduction, we do not
consider increasing the emission reduction to 98 percent to be
reasonable, and we are not proposing to revise the OSWRO MACT standards
for process vents pursuant to CAA section 112(d)(6) to require this
level of emissions control. We solicit comment on our analysis, and as
noted in section IV.B.2, we also solicit comments regarding the
emissions controls proposed as a result of this technology review,
given the uncertainty in the emissions estimates and the potential
impact on the estimates of cost effectiveness.
D. What other actions are we proposing?
We are also proposing revisions to the startup, shutdown and
malfunction (SSM) provisions of the MACT rule to ensure that they are
consistent with the court decision in Sierra Club v. EPA, 551 F. 3d
1019 (D.C. Cir. 2008), which vacated two provisions that exempted
sources from the requirement to comply with otherwise applicable
section 112(d) emission standards during periods of SSM. Second, we are
proposing to require electronic reporting of emissions test results.
Third, we are proposing to revise the routine maintenance provisions
and limit those provisions only to tanks routing emissions to a control
device. Fourth, we are proposing to clarify what ``seal the open end at
all times'' means for open-ended lines and valves in the equipment leak
provisions of the rule. Fifth, we are proposing that emissions of HAP
from safety devices and closure devices directly to the atmosphere are
prohibited, and we are proposing to require monitoring of pressure
releases from pressure relief devices (PRDs) that release directly to
the atmosphere. Sixth, we are proposing minor clarifications to the
sample run times and sample site location required for some performance
test methods, and we are proposing to allow the use of a different
performance test method in two cases. Seventh, we are proposing various
minor clarifications and corrections to the rule. In addition to these
proposed revisions, we are seeking comments containing information
regarding flares used by facilities in this source category. We present
details and the rationales for the proposed changes in the following
sections.
1. Startup, Shutdown and Malfunctions
a. Background
In its 2008 decision in Sierra Club v. EPA, 551 F.3d 1019 (D.C.
Cir. 2008), the United States Court of Appeals for the District of
Columbia Circuit vacated portions of two provisions in the EPA's CAA
section 112 regulations governing the emissions of HAP during periods
of SSM. Specifically, the Court vacated the SSM exemption contained in
40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1) holding that under section
302(k) of the CAA, emissions standards or limitations must be
continuous in nature and that the SSM exemption violates the CAA's
requirement that some section 112 standards apply continuously.
We are proposing to eliminate the SSM exemption in the OSWRO
NESHAP. Consistent with Sierra Club v. EPA, we are proposing standards
in this rule that apply at all times. We are also proposing several
revisions to Table 2 (the General Provisions Applicability Table) as is
explained in more detail below. For example, we are proposing to
eliminate the incorporation of the General Provisions' requirement that
the source develop an SSM plan. We also are proposing to eliminate and
revise certain recordkeeping and reporting requirements related to the
SSM exemption as further described below.
The EPA has attempted to eliminate provisions that are
inappropriate, unnecessary, or redundant in the absence of the SSM
exemption in this proposal. We are specifically seeking comment on
whether we have successfully done so.
In proposing the standards in this rule, the EPA has taken into
account startup and shutdown periods and, for the reasons explained
below, has not proposed alternate standards for those periods.
Information on periods of startup and shutdown received from OSWRO
facilities through the CAA section 114 questionnaire responses indicate
that emissions during these periods are the same as during normal
operations. The facilities do not process waste unless and until their
control devices are operating to fully control emissions. Therefore,
separate standards for periods of startup and shutdown are not
necessary and are not being proposed. We solicit comment on our
findings and conclusions regarding periods of startup and shutdown at
OSWRO facilities.
Periods of startup, normal operations, and shutdown are all
predictable and routine aspects of a source's operations. However, by
contrast, malfunction is defined as a ``sudden, infrequent, and not
reasonably preventable failure of air pollution control and monitoring
equipment, process equipment or a process to operate in a normal or
usual manner * * *'' (40 CFR 63.2). The EPA has determined that CAA
section 112 does not require that emissions that occur during periods
of malfunction be factored into development of CAA section 112
standards. Under section 112, emissions standards for new sources must
be no less stringent than the level ``achieved'' by the best controlled
similar source and for existing sources generally must be no less
stringent than the average emission limitation ``achieved'' by the best
performing 12 percent of sources in the category. There is nothing in
section 112 that directs the EPA to consider malfunctions in
determining the level ``achieved'' by the best performing sources when
setting emission standards. As the DC Circuit has recognized, the
phrase ``average emissions limitation achieved by the best performing
12 percent of sources ``says nothing about how the performance of the
best units is to be calculated.'' Nat'l Ass'n of Clean Water Agencies
v. EPA, 734 F.3d 1115, 1141 (D.C. Cir. 2013). While the EPA accounts
for variability in setting emissions standards, nothing in section 112
requires the EPA to consider malfunctions as part of that analysis. A
malfunction should not be treated in the same manner as the type of
variation in performance that occurs during routine operations of a
source. A malfunction is a failure of the source to perform in a
``normal or usual manner'' and no statutory language compels the EPA to
consider such events in setting standards based on ``best performers.''
Further, accounting for malfunctions in setting emissions standards
would be difficult, if not impossible, given the
[[Page 37874]]
myriad different types of malfunctions that can occur across all
sources in the category and given the difficulties associated with
predicting or accounting for the frequency, degree, and duration of
various malfunctions that might occur. As such, the performance of
units that are malfunctioning is not ``reasonably'' foreseeable. See,
e.g., Sierra Club v. EPA, 167 F. 3d 658, 662 (D.C. Cir. 1999) (the EPA
typically has wide latitude in determining the extent of data-gathering
necessary to solve a problem. We generally defer to an agency's
decision to proceed on the basis of imperfect scientific information,
rather than to ``invest the resources to conduct the perfect study.'').
See also Weyerhaeuser v. Costle, 590 F.2d 1011, 1058 (D.C. Cir. 1978)
(``In the nature of things, no general limit, individual permit, or
even any upset provision can anticipate all upset situations. After a
certain point, the transgression of regulatory limits caused by
`uncontrollable acts of third parties,' such as strikes, sabotage,
operator intoxication or insanity, and a variety of other
eventualities, must be a matter for the administrative exercise of
case-by-case enforcement discretion, not for specification in advance
by regulation.''). In addition, the goal of a ``best controlled or best
performing source'' is to operate in such a way as to avoid
malfunctions of the source and accounting for malfunctions could lead
to standards that are significantly less stringent than levels that are
achieved by a well-performing non-malfunctioning source. It is
reasonable to interpret section 112 to avoid such a result. The EPA's
approach to malfunctions is consistent with CAA section 112 and is a
reasonable interpretation of the statute.
In the event that a source fails to comply with the applicable CAA
section 112(d) standards as a result of a malfunction event, the EPA
would determine an appropriate response based on, among other things,
the good faith efforts of the source to minimize emissions during
malfunction periods, including preventative and corrective actions, as
well as root cause analyses to ascertain and rectify excess emissions.
The EPA would also consider whether the source's failure to comply with
the CAA section 112(d) standard was, in fact, ``sudden, infrequent, not
reasonably preventable'' and was not instead ``caused in part by poor
maintenance or careless operation.'' 40 CFR 63.2 (definition of
malfunction). Further, to the extent the EPA files an enforcement
action against a source for violation of an emission standard, the
source can raise any and all defenses in that enforcement action, and
the federal district court will determine what, if any, relief is
appropriate. The same is true for citizen enforcement actions.
Similarly, the presiding officer in an administrative proceeding can
consider any defense raised and determine whether administrative
penalties are appropriate.
In several prior rules, the EPA had included an affirmative defense
to civil penalties for violations caused by malfunctions in an effort
to create a system that incorporates some flexibility, recognizing that
there is a tension, inherent in many types of air regulations, to
ensure adequate compliance, while simultaneously recognizing that
despite the most diligent of efforts, emission standards may be
violated under circumstances entirely beyond the control of the source.
Although the EPA recognized that its case-by-case enforcement
discretion provides sufficient flexibility in these circumstances, it
included the affirmative defense to provide a more formalized approach
and more regulatory clarity. See Weyerhaeuser Co. v. Costle, 590 F.2d
1011, 1057-58 (D.C. Cir. 1978) (holding that an informal case-by-case
enforcement discretion approach is adequate); but see Marathon Oil Co.
v. EPA, 564 F.2d 1253, 1272-73 (9th Cir. 1977) (requiring a more
formalized approach to consideration of ``upsets beyond the control of
the permit holder.''). Under the EPA's regulatory affirmative defense
provisions, if a source could demonstrate in a judicial or
administrative proceeding that it had met the requirements of the
affirmative defense in the regulation, civil penalties would not be
assessed. Recently, the United States Court of Appeals for the District
of Columbia Circuit vacated such an affirmative defense in one of the
EPA's section 112(d) regulations. NRDC v. EPA, No. 10-1371 (D.C. Cir.
April 18, 2014) 2014 U.S. App. LEXIS 7281 (vacating affirmative defense
provisions in a section 112(d) rule establishing emission standards for
Portland cement kilns). The court found that the EPA lacked authority
to establish an affirmative defense for private civil suits and held
that under the CAA, the authority to determine civil penalty amounts
lies exclusively with the courts, not the EPA. Specifically, the Court
found: ``As the language of the statute makes clear, the courts
determine, on a case-by-case basis, whether civil penalties are
`appropriate.''' See NRDC, 2014 U.S. App. LEXIS 7281 at *21 (``[U]nder
this statute, deciding whether penalties are `appropriate' in a given
private civil suit is a job for the courts, not EPA.''). In light of
NRDC, the EPA is not including a regulatory affirmative defense
provision in this proposed rule. As explained above, if a source is
unable to comply with emissions standards as a result of a malfunction,
the EPA may use its case-by-case enforcement discretion to provide
flexibility, as appropriate. Further, as the DC Circuit recognized, in
an EPA or citizen enforcement action, the court has the discretion to
consider any defense raised and determine whether penalties are
appropriate. Cf. NRDC, 2014 U.S. App. LEXIS 7281 at *24. (arguments
that violation were caused by unavoidable technology failure can be
made to the courts in future civil cases when the issue arises). The
same logic applies to EPA administrative enforcement actions.
b. Specific SSM-Related Proposed Changes
To address the United States Court of Appeals for the District of
Columbia Circuit vacatur of portions of the EPA's CAA section 112
regulations governing the emissions of HAP during periods of SSM, we
are proposing revisions and additions to certain provisions of the
OSWRO rule. As described in detail below, we are proposing to revise
the General Provisions applicability table (Table 2 to Subpart DD) in
several of the references related to requirements that apply during
periods of SSM. We are also proposing revisions related to the
following provisions of the OSWRO rule: (1) The general duty to
minimize emissions at all times; (2) the requirement for sources to
comply with the emission limits in the rule at all times, with
clarifications for what constitutes a deviation; (3) performance
testing conditions requirements; (4) excused monitoring excursions
provisions; and (5) malfunction recordkeeping and reporting
requirements.
i. General Duty
We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.6(e) by adding rows specifically for 40 CFR
63.6(e)(1)(i), 63.6(e)(1)(ii), 63.6(e)(1)(iii), and 63.6(e)(3) and to
include a ``no'' in the second column for the 40 CFR 63.6(e)(1)(i)
entry. Section 63.6(e)(1)(i) describes the general duty to minimize
emissions. Some of the language in that section is no longer necessary
or appropriate in light of the elimination of the SSM exemption. We are
proposing instead to add general duty regulatory text at 40 CFR
63.683(e) that reflects the
[[Page 37875]]
general duty to minimize emissions while eliminating the reference to
periods covered by an SSM exemption. The current language in 40 CFR
63.6(e)(1)(i) characterizes what the general duty entails during
periods of SSM. With the elimination of the SSM exemption, there is no
need to differentiate between normal operations, startup and shutdown,
and malfunction events in describing the general duty. Therefore the
language the EPA is proposing for 40 CFR 63.683(e) does not include
that language from 40 CFR 63.6(e)(1).
We are also proposing to include a ``no'' in the second column for
the newly added entry for 40 CFR 63.6(e)(1)(ii). Section 63.6(e)(1)(ii)
imposes requirements that are not necessary with the elimination of the
SSM exemption or are redundant with the general duty requirement being
added at 63.683(e).
The provisions of 40 CFR 63.6(e)(1)(iii) still apply, and we are
keeping the ``yes'' in the second column for that section. For 40 CFR
63.6(e)(2), we are proposing to include a ``no'' in the second column
for that section because it is a reserved section in the General
Provisions.
We are also proposing to clarify in the applicability section of 40
CFR 63.680(g)(1) and (2) that the emission limits of subpart DD apply
at all times except when the affected source is not operating and that
the owner or operator must not shut down items of equipment required or
used for compliance with the requirements of subpart DD.
ii. SSM Plan
We are also proposing to include a ``no'' in the second column for
the newly added 40 CFR 63.6(e)(3) entry. Generally, this paragraph
requires development of an SSM plan and specifies SSM recordkeeping and
reporting requirements related to the SSM plan. As noted, the EPA is
proposing to remove the SSM exemptions. Therefore, affected units will
be subject to an emission standard during such events. The
applicability of a standard during such events will ensure that sources
have ample incentive to plan for and achieve compliance and thus the
SSM plan requirements are no longer necessary.
iii. Compliance With Standards
We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.6(f)(1) by changing the ``yes'' in column 2 to a
``no.'' The current language of 40 CFR 63.6(f)(1) exempts sources from
non-opacity standards during periods of SSM. As discussed above, the
court in Sierra Club vacated the exemptions contained in this provision
and held that the CAA requires that some section 112 standard apply
continuously. Consistent with Sierra Club, the EPA is proposing to
revise standards in this rule to apply at all times.
iv. Performance Testing
We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.7(e)(1) by changing the ``yes'' in column 2 to a
``no.'' Section 63.7(e)(1) describes performance testing requirements.
The EPA is instead proposing to add a performance testing requirement
at 40 CFR 63.694(l). The performance testing requirements we are
proposing to add differ from the General Provisions performance testing
provisions in several respects. The regulatory text does not include
the language in 40 CFR 63.7(e)(1) that restated the SSM exemption.
However, consistent with 40 CFR 63.7(e)(1), performance tests conducted
under this subpart should be based on representative performance (i.e.,
performance based on normal operating conditions) of the affected
source. The EPA is proposing to add language that requires the owner or
operator to record the process information that is necessary to
document operating conditions during the test and include in such
record an explanation to support that such conditions represent normal
operation. Section 63.7(e) requires that the owner or operator make
available to the Administrator such records ``as may be necessary to
determine the condition of the performance test'' upon request, but
does not specifically require the information to be recorded. The
regulatory text the EPA is proposing to add to this provision builds on
that requirement and makes explicit the requirement to record the
information.
v. Monitoring
We are proposing to revise the General Provisions table (Table 2)
entries for 40 CFR 63.8(c)(1)(i) and (iii) by changing the ``yes'' in
column 2 to a ``no.'' The cross-references to the general duty and SSM
plan requirements in those subparagraphs are not necessary in light of
other requirements of 40 CFR 63.8 that require good air pollution
control practices (40 CFR 63.8(c)(1)) and that set out the requirements
of a quality control program for monitoring equipment (40 CFR 63.8(d)).
vi. Recordkeeping
We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(b)(2)(i) by changing the ``yes'' in column 2 to
a ``no.'' Section 63.10(b)(2)(i) describes the recordkeeping
requirements during startup and shutdown. These recording provisions
are no longer necessary because the EPA is proposing that recordkeeping
and reporting applicable to normal operations will apply to startup and
shutdown. In the absence of special provisions applicable to startup
and shutdown, such as a startup and shutdown plan, there is no reason
to retain additional recordkeeping for startup and shutdown periods.
We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(b)(2)(ii) by changing the ``yes'' in column 2 to
a ``no.'' Section 63.10(b)(2)(ii) describes the recordkeeping
requirements during a malfunction. The EPA is proposing to add such
requirements to 40 CFR 63.696(h). The regulatory text we are proposing
to add differs from the General Provisions it is replacing in that the
General Provisions require the creation and retention of a record of
the occurrence and duration of each malfunction of process, air
pollution control, and monitoring equipment. The EPA is proposing that
this requirement apply to any failure to meet an applicable standard
and is requiring that the source record the date, time, and duration of
the failure rather than the ``occurrence.'' The EPA is also proposing
to add to 40 CFR 63.696(h) a requirement that sources keep records that
include a list of the affected source or equipment and actions taken to
minimize emissions, an estimate of the volume of each regulated
pollutant emitted over the standard for which the source failed to meet
the standard, and a description of the method used to estimate the
emissions. Examples of such methods would include product-loss
calculations, mass balance calculations, measurements when available,
or engineering judgment based on known process parameters. The EPA is
proposing to require that sources keep records of this information to
ensure that there is adequate information to allow the EPA to determine
the severity of any failure to meet a standard, and to provide data
that may document how the source met the general duty to minimize
emissions when the source has failed to meet an applicable standard.
We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(b)(2)(iv) by changing
[[Page 37876]]
the ``yes'' in column 2 to a ``no.'' When applicable, the provision
requires sources to record actions taken during SSM events when actions
were inconsistent with their SSM plan. The requirement is no longer
appropriate because SSM plans will no longer be required. The
requirement previously applicable under 40 CFR 63.10(b)(2)(iv)(B) to
record actions to minimize emissions and record corrective actions is
now applicable by reference to 40 CFR 63.696(h).
We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(b)(2)(v) by changing the ``yes'' in column 2 to
a ``no.'' When applicable, the provision requires sources to record
actions taken during SSM events to show that actions taken were
consistent with their SSM plan. The requirement is no longer
appropriate because SSM plans will no longer be required.
vii. Reporting
We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(d)(5)(i) by consolidating it with the entry for
63.10(d)(5)(ii) and changing the ``yes'' in column 2 to ``no.'' Section
63.10(d)(5)(i) describes the reporting requirements for startups,
shutdowns, and malfunctions. To replace the General Provisions
reporting requirements, the EPA is proposing to add reporting
requirements to 40 CFR 63.697(b)(3). The replacement language differs
from the General Provisions requirement in that it eliminates periodic
SSM reports as a stand-alone report. We are proposing language that
requires sources that fail to meet an applicable standard at any time
to report the information concerning such events in the semi-annual
summary report already required under this rule. We are proposing that
the report must contain the number, date, time, duration, and the cause
of such events (including unknown cause, if applicable), a list of the
affected source or equipment, an estimate of the quantity of each
regulated pollutant emitted over any emission limit, and a description
of the method used to estimate the emissions.
Examples of such methods would include product-loss calculations,
mass balance calculations, measurements when available, or engineering
judgment based on known process parameters. The EPA is proposing this
requirement to ensure that there is adequate information to determine
compliance, to allow the EPA to determine the severity of the failure
to meet an applicable standard, and to provide data that may document
how the source met the general duty to minimize emissions during a
failure to meet an applicable standard.
We will no longer require owners or operators to determine whether
actions taken to correct a malfunction are consistent with an SSM plan,
because plans would no longer be required. The proposed amendments
therefore eliminate the cross reference to 40 CFR 63.10(d)(5)(i) that
contains the description of the previously required SSM report format
and submittal schedule from this section. These specifications are no
longer necessary because the events will be reported in otherwise
required reports with similar format and submittal requirements.
We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(d)(5)(ii) by consolidating it with the entry for
63.10(d)(5)(i) and changing the ``yes'' in column 2 to a ``no.''
Section 63.10(d)(5)(ii) describes an immediate report for startups,
shutdown, and malfunctions when a source failed to meet an applicable
standard but did not follow the SSM plan. We will no longer require
owners and operators to report when actions taken during a startup,
shutdown, or malfunction were not consistent with an SSM plan, because
plans would no longer be required.
2. Electronic Reporting
In this proposal, the EPA is describing a process to increase the
ease and efficiency of performance test data submittal while improving
data accessibility. Specifically, the EPA is proposing that owners and
operators of OSWRO facilities submit electronic copies of required
performance test reports by direct computer-to-computer electronic
transfer using EPA-provided software. The direct computer-to-computer
electronic transfer is accomplished through the EPA's Central Data
Exchange (CDX) using the Compliance and Emissions Data Reporting
Interface (CEDRI). The Central Data Exchange is EPA's portal for
submittal of electronic data. The EPA-provided software is called the
Electronic Reporting Tool (ERT) which is used to generate electronic
reports of performance tests and evaluations. The ERT generates an
electronic report package which will be submitted using the CEDRI. The
submitted report package will be stored in the CDX archive (the
official copy of record) and EPA's public database called WebFIRE. All
stakeholders will have access to all reports and data in WebFIRE and
accessing these reports and data will be very straightforward and easy
(see the WebFIRE Report Search and Retrieval link at http://cfpub.epa.gov/webfire/index.cfm?action=fire.searchERTSubmission). A
description and instructions for use of the ERT can be found at http://www.epa.gov/ttn/chief/ert/index.html and CEDRI can be accessed through
the CDX Web site (www.epa.gov/cdx). A description of the WebFIRE
database is available at: http://cfpub.epa.gov/oarweb/index.cfm?action=fire.main.
The proposal to submit performance test data electronically to the
EPA applies only to those performance tests conducted using test
methods that are supported by the ERT. The ERT supports most of the
commonly used EPA reference methods. A listing of the pollutants and
test methods supported by the ERT is available at: http://www.epa.gov/ttn/chief/ert/index.html.
We believe that industry would benefit from this proposed approach
to electronic data submittal. Specifically, by using this approach,
industry will save time in the performance test submittal process.
Additionally, the standardized format that the ERT uses allows sources
to create a more complete test report resulting in less time spent on
data backfilling if a source failed to include all data elements
required to be submitted. Also through this proposal industry may only
need to submit a report once to meet the requirements of the applicable
subpart because stakeholders can readily access these reports from the
WebFIRE database. This also benefits industry by cutting back on
recordkeeping costs as the performance test reports that are submitted
to the EPA using CEDRI are no longer required to be retained in hard
copy, thereby, reducing staff time needed to coordinate these records.
Since the EPA will have performance test data in hand, we expect
that there may be fewer or less substantial data collection requests in
conjunction with prospective required residual risk assessments or
technology reviews. This would result in a decrease in staff time
needed to respond to data collection requests.
State, local and tribal air pollution control agencies (S/L/Ts) may
also benefit from having electronic versions of the reports they are
now receiving. For example, S/L/Ts may be able to conduct a more
streamlined and accurate review of electronic data submitted to them.
For example, the ERT would allow for an electronic review process,
rather than a manual data assessment, therefore, making review and
evaluation of the source provided data and calculations easier and more
efficient. In addition, the public stands to benefit from electronic
[[Page 37877]]
reporting of emissions data because the electronic data will be easier
for the public to access. How the air emissions data are collected,
accessed and reviewed will be more transparent for all stakeholders.
One major advantage of the proposed submittal of performance test
data through the ERT is a standardized method to compile and store much
of the documentation required to be reported by this rule. The ERT
clearly states what testing information would be required by the test
method and has the ability to house additional data elements that might
be required by a delegated authority.
In addition the EPA must have performance test data to conduct
effective reviews of CAA sections 111, 112 and 129 standards, as well
as for many other purposes including compliance determinations,
emission factor development and annual emission rate determinations. In
conducting these required reviews, the EPA has found it ineffective and
time consuming, not only for us, but also for regulatory agencies and
source owners and operators, to locate, collect and submit performance
test data. In recent years, though, stack testing firms have typically
collected performance test data in electronic format, making it
possible to move to an electronic data submittal system that would
increase the ease and efficiency of data submittal and improve data
accessibility.
A common complaint heard from industry and regulators is that
emission factors are outdated or not representative of a particular
source category. With timely receipt and incorporation of data from
most performance tests, the EPA would be able to ensure that emission
factors, when updated, represent the most current range of operational
practices. Finally, another benefit of the proposed data submittal to
WebFIRE electronically is that these data would greatly improve the
overall quality of existing and new emissions factors by supplementing
the pool of emissions test data for establishing emissions factors.
In summary, in addition to supporting regulation development,
control strategy development and other air pollution control
activities, having an electronic database populated with performance
test data would save industry, state, local, tribal agencies and the
EPA significant time, money and effort, while also improving the
quality of emission inventories and air quality regulations.
3. Routine Maintenance
40 CFR 63.693(b)(3)(i) of the OSWRO NESHAP allows for control
devices to be bypassed to perform planned routine maintenance of the
closed-vent system or control device in situations when the routine
maintenance cannot be performed during periods that the emission point
vented to the control device is shut down. The facility is allowed to
bypass the control device for up to 240 hours per year.
The routine maintenance provision was originally established in the
Hazardous Organic NESHAP (HON) (see 40 CFR 63.119(e)(3)-(4); 57 FR
62710, December 31, 1992 (proposed); 59 FR 19402, April 22, 1994
(final)) for facilities that elected to use a closed vent system and
control device to comply with the emission limitation requirements for
tanks. We included the routine maintenance provision in the HON for
tanks routing emissions to control devices because the estimated HAP
emissions to degas the tank would be greater than the emissions that
would result if the tank emitted directly to the atmosphere for a short
period of time during routine maintenance of the control device.
We intended for the OSWRO NESHAP to track the HON maintenance
provisions, and as such, those provisions should have been limited to
tanks. We have not identified a basis for applying the routine
maintenance provisions in the OSWRO NESHAP to emission points other
than tanks. Therefore, we are proposing to limit the provision to tanks
routing emissions to a control device, consistent with the rationale
provided in the HON. We request comment on this proposed revision.
4. Open-Ended Valves and Lines
The OSWRO NESHAP at 40 CFR 63.691(b) requires an owner or operator
to control emissions from equipment leaks according to the requirements
of either 40 CFR part 61, subpart V or 40 CFR part 63, subpart H. For
open-ended valves and lines, both subpart V in Sec. 61.242-6(a) and
subpart H in Sec. 63.167(a) require that the open end be equipped with
a cap, blind flange, plug, or second valve that shall ``seal the open
end.'' However, ``seal'' is not defined in either subpart, leading to
uncertainty for the owner or operator as to whether compliance is being
achieved. Inspections under the EPA's Air Toxics LDAR initiative have
provided evidence that while certain open-ended lines may be equipped
with a cap, blind flange, plug or second valve, these are not providing
a ``seal'' as the EPA interprets the term.\25\
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\25\ See ``Region V OEL data for VV rulemaking'' available in
the docket for this action.
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In response to this uncertainty, we are proposing to amend 40 CFR
63.691(a) to clarify what ``seal the open end'' means for open-ended
valves and lines. This proposed clarification explains that, for the
purpose of complying with the requirements of 40 CFR 63.167 of subpart
H, open-ended valves and lines are ``sealed'' by the cap, blind flange,
plug, or second valve instrument monitoring of the open-ended valve or
line conducted according to Method 21 of 40 CFR part 60, appendix A
indicates no readings of 500 ppm or greater.
In addition, 40 CFR 63.167(d) of subpart H and 40 CFR 61.242-6(d)
of subpart V exempt open-ended valves and lines that are in an
emergency shutdown system, and which are designed to open
automatically, from the requirements to be equipped with a cap, blind
flange, plug, or second valve that seals the open end. We are proposing
that these open-ended valves and lines follow the requirements of 40
CFR 63.693(c)(2) for bypass devices that could be used to divert a vent
stream from the closed-vent system to the atmosphere, which would
require that each such open-ended line be equipped with either a flow
indicator or a seal or locking device. We are also proposing
recordkeeping and reporting requirements in 40 CFR 63.696(j)(2) and 40
CFR 63.697(b)(6) for these open-ended values and lines.
We solicit comments on our proposed approach to reducing the
compliance uncertainty associated with ``sealed'' open-ended valves and
lines and our proposed requirements for open-ended valves and lines
that are in an emergency shutdown system and are designed to open
automatically.
5. Safety Devices, Pressure Tanks, Bypasses and PRDs
The OSWRO MACT standards contain requirements for safety devices,
closure devices on pressure tanks, PRDs and bypasses, established with
the recognition that emission releases to the atmosphere from these
devices and from bypasses of control equipment occur only in the event
of unplanned and unpredictable events. While emissions vented to the
atmosphere in these events may contain HAP that would otherwise be
subject to the OSWRO MACT emission standards, the OSWRO MACT rule
followed the EPA's former practice prior to the Sierra Club decision of
exempting malfunction events from otherwise applicable
[[Page 37878]]
emissions standards. Consequently, as these events were assumed to
occur during malfunctions, the OSWRO MACT standards did not restrict
emissions of HAP from these equipment or events to the atmosphere.
In the Sierra Club decision, the Court determined that the SSM
exemption violated the CAA and vacated the regulatory provisions in the
General Provisions containing the exemption. See section IV.D.1 of this
preamble for additional discussion. To ensure the OSWRO MACT standards
are consistent with the Court's action, we are proposing to remove the
SSM exemption from the rule. In addition, in order for our treatment of
malfunction-caused releases to the atmosphere to conform with the
reasoning of the Court's ruling, we are proposing to add a provision
that releases of HAP listed in Table 1 of 40 CFR part 63, subpart DD
directly to the atmosphere from PRDs and closure devices on pressure
tanks in off-site material service are prohibited. We are also
proposing to prohibit bypasses that divert a process vent or closed
vent system stream to the atmosphere such that it does not first pass
through an emission control device, except to perform planned routine
maintenance of the closed-vent system or emission control device for
tanks, as discussed in section IV.D.3 of this preamble. We are further
proposing to require owners or operators to keep records and report any
bypass and the amount of HAP released to the atmosphere with the next
periodic report. In addition, to add clarity to these proposed
provisions, we are proposing to add definitions for ``bypass,''
``pressure release,'' ``pressure relief device or valve,'' ``in gas/
vapor service,'' ``in light liquid service'' ``in heavy liquid
service'' and ``in liquid service'' to 40 CFR part 63, subpart DD. We
are also proposing to remove the definition of ``safety device'' and
the provisions related to safety devices from 40 CFR part 63, subpart
DD, which would overlap with and be redundant of parts of the proposed
definition of ``pressure relief device or valve'' and the provisions
related to these devices. To our knowledge, pressure relief devices or
valves are the only safety devices used in OSWRO processes.
To address potential releases from PRDs, we are also proposing to
require facility owners or operators subject to the OSWRO MACT
standards to employ monitoring of PRDs in off-site material service
using a device or monitoring system that is capable of: (1) Identifying
the pressure release; (2) recording the time and duration of each
pressure release; and (3) notifying operators immediately that a
pressure release is occurring. We are further proposing to require
owners or operators to keep records and report any pressure release and
the amount of HAP released to the atmosphere with the next periodic
report.
Pressure releases to the atmosphere from PRDs in off-site material
service have the potential to emit large quantities of HAP. Where a
release occurs, it is important to identify and mitigate it as quickly
as possible. We recognize that releases from PRDs sometimes occur in
order to protect systems from failures that could endanger worker
safety and the systems that the PRDs are designed to protect. We have
provided a balanced approach designed to minimize HAP emissions while
recognizing that these events may be unavoidable even in a well-
designed and maintained system. For purposes of estimating the costs of
this requirement, we assumed that operators would install electronic
indicators on each relief device that vents to the atmosphere to
identify and record the time and duration of each pressure release.
However, we are proposing that owners and operators could choose to use
an existing system, such as a parameter monitoring system, as long as
it is sufficient to identify a pressure release, notify operators
immediately that a release is occurring and record the time and
duration of the release.
Based on our cost assumptions, the nationwide capital cost of
installing these monitors for the OSWRO industry is approximately $1.75
million and the annualized cost of installing and operating these
monitors is $250,000 per year. As noted above, the owner or operator
may use parameter monitoring systems already in place. Therefore, our
costs based on the installation of electronic indicators on each relief
device that vents to the atmosphere is conservative and likely
overstates the costs.
6. Performance Test Method Clarifications and Alternative Methods
The OSWRO NESHAP at 40 CFR 63.694 specifies test methods and
procedures to be used in determining compliance with the requirements
of subpart DD. We are proposing several minor changes to these
provisions to correct errors and to provide consistency, clarification
and flexibility.
We are proposing several minor clarifications to align the testing
requirements with standard testing practices. We are proposing that
test runs last ``at least 1 hour'', rather than stating that tests last
``1 hour'' in Sec. 63.694(f)(1) and (i)(1). This is consistent with
standard testing practice and other provisions of the rule that specify
a minimum sampling time instead of an absolute sampling time. Requiring
a minimum sampling time allows owners and operators to conduct longer
sampling runs when necessary. For example, an owner or operator may
conduct longer sampling runs to achieve a lower detection limit for a
specific compound. We are proposing to specify that a minimum of three
test runs are required in Sec. 63.694(l)(3)(i) and (l)(4)(i),
consistent with the Part 63 General Provisions and standard testing
practices. We are proposing to specify in Sec. 63.694(m)(2) that in
the determination of process vent stream flow rate and total HAP
concentration, the sample site selected must be at the center of the
vent for vents smaller than 0.10 meter in diameter. EPA Methods 1 and
1A do not apply to stack diameters smaller than 0.10 meter in diameter,
and the regulation as currently written states that it is unnecessary
to traverse vents less than 0.10 meter in diameter, but is unclear on
how sampling point selection must be chosen. We are proposing to
clarify that the sampling point must be at the center of the vent; this
sample point is the point most likely to provide a representative
sample of the gas stream.
To provide consistency with other parts of the OSWRO MACT
standards, we are proposing to clarify the requirements of Sec.
63.694(j)(3) for determining the maximum HAP vapor pressure for off-
site material in a tank if the Administrator and the owner or operator
disagree on a determination of the maximum HAP vapor pressure for an
off-site material stream using knowledge. We are proposing that results
from direct measurement of the HAP vapor pressure must be used in these
instances. This is consistent with Sec. 63.694(b)(3)(iv), which uses
the same language for VOHAP measurements.
We also are proposing to correct a citation in Sec. 63.694(k)(3).
The regulation currently references the wrong section of Method 21 for
instrument response factors. The appropriate section in EPA Method 21
is 8.1.1, not 3.1.2(a).
We are proposing to allow the use of either EPA Method 25A or
Method 18 in Sec. 63.694(l)(3) and (4). We are clarifying that Method
25A must be used for determining compliance with the enclosed
combustion device total organic compound (TOC) limit, while Method 18
is used for determining compliance with the total HAP concentration
limit. We are making this change because Method 25A is a flame
ionization method that measures concentration as carbon equivalents. It
[[Page 37879]]
is preferred over Method 18 for the measurement of TOC. Method 18 is
used to determine the concentration of individual compounds, making it
appropriate for measuring individual HAPs that can be summed and
compared with the total HAP limit, especially when a finite list of
HAPs is specified (such as in Table 1 of the OSWRO NESHAP). Because TOC
includes all organic compounds (minus methane and ethane) and Method 18
requires a set list of individual compounds to be measured. In order to
use Method 18 for TOC measurements, one would have to know every
organic compound in the gas stream and analyze each individually, which
is a difficult and nearly impossible task in most cases. Therefore, we
are proposing that TOC is to be measured with Method 25A and total HAP
is to be measured with Method 18. The changes in how the test methods
are applied and how TOC is most appropriately measured result in
changes in some of the equations in Sec. 63.694 as well.
We are proposing additional flexibility in some of the test methods
that are allowed by the OSWRO NESHAP. We are including the use of EPA
Method 3A as an alternative to EPA Method 3B in Sec.
63.694(l)(4)(iii)(A) for determining the oxygen concentration to use in
oxygen correction equations. EPA Method 3A is just as effective as EPA
Method 3B in determining oxygen concentration. We have also included
the use of EPA Methods 2F and 2G as options for flow rate measurement
in Sec. 63.694(l)(2) and (m)(3). These methods are newer velocity
measurement methods that were published after the original OSWRO rule.
By allowing these test method alternatives in the rule, we are
providing greater flexibility to sources and easing the burden on
sources and delegated agencies by reducing the number of potential
alternative method requests.
7. Other Clarifications and Corrections
We are proposing several miscellaneous minor changes to improve the
clarity of the rule requirements. These proposed changes include:
Updating the list in Sec. 63.684(b)(5) of combustion
devices that may be used to destroy the HAP contained in an off-site
material stream, to include incinerators, boilers or industrial
furnaces for which the owner or operator complies with the requirements
of 40 CFR part 63, subpart EEE. Where the OSWRO MACT standards
currently require that combustion devices used for the purposes of
compliance with the OSWRO MACT standards must be regulated under
various subparts of RCRA, many of these units now comply with 40 CFR
part 63, subpart EEE, which had not been promulgated when the OSWRO
MACT standards were developed. We are also proposing conforming changes
to the boiler and process heater control device requirements in Sec.
63.693(g)(1)(v). These changes clarify that combustion units complying
with the requirements of subpart EEE may be used for the purposes of
compliance with the OSWRO MACT standards.
Revising the tank control level tables and the text in
Sec. 63.685(b) to clarify the control level required for tanks of any
capacity (effectively those less than 75 m\3\) with a vapor pressure of
76.6 kPa or greater. Tanks meeting these capacity and vapor pressure
thresholds are not included in the control level tables referred to in
Sec. 63.685(b), currently Tables 3 and 4 of the OSWRO NESHAP, and
instead text is included in Sec. 63.685(b)(4) for these tanks. To
clarify the requirements for these tanks, we are proposing to specify
the requirements for these tanks in the tank control level tables
(proposed Tables 3, 4 and 5) and remove the text in Sec. 63.685(b)(4).
Clarifying that where Sec. 63.691 requires the owner or
operator to control the HAP emitted from equipment leaks in accordance
with either 40 CFR part 61, subpart V or 40 CFR part 63, subpart H, the
definitions in 40 CFR 61.241 and 40 CFR 63.161 apply, with the
differences listed, for the purposes of the OSWRO NESHAP.
Clarifying the requirement of Sec. 63.683(c)(1)(ii) that
the average VOHAP concentration of the off-site material must be less
than 500 ppmw at the point-of-delivery and clarifying the requirements
of Sec. 63.693(f)(1)(i)(B) and Sec. 63.693(f)(1)(ii)(B) are to
achieve a total incinerator outlet concentration of less than or equal
to 20 ppmv on a dry basis corrected to 3 percent oxygen. Due to
clerical errors, the ppm values of these requirements are not in the
current OSWRO NESHAP, and we are proposing to insert them.
Clarifying in Sec. Sec. 63.684(h), 63.693(b)(8) and
63.694(b)(3)(iv) that the Administrator may require a performance test,
revisions to a control device design analysis, or that direct
measurement be used in the determination of a VOHAP concentration,
rather than that the Administrator may only request such actions.
Revising several references to the Part 63 General
Provisions in Table 2 to correct errors, including errors where the
entries in Table 2 conflict with the regulatory text in subpart DD and
where references to specific sections of the General Provisions do not
exist or are reserved.
8. Flare Performance
In addition to our proposed actions discussed above, we are seeking
comments on the performance of flares used to control HAP emissions in
this source category, as governed by the EPA's General Provisions at 40
CFR 63.11(b). In April 2012, the EPA conducted an external peer review
of a draft technical report, ``Parameters for Properly Designed and
Operated Flares'' (http://www.epa.gov/ttn/atw/flare/2012flaretechreport.pdf) (``draft flare technical report''). In this
report, the EPA evaluated test data and identified a variety of
parameters that may affect flare performance and that could be
monitored to help ensure good combustion efficiency. Based on feedback
received from the external ad-hoc peer review panel, the EPA has since
undertaken an initiative to re-evaluate parameters that may affect
overall flare performance at source categories known to use flares for
controlling HAP emissions (e.g., petroleum refining).
Currently, OSWRO sources may choose from a variety of control
techniques to control emissions from this source category. One option
is to operate a flare to reduce HAP emissions in accordance with the
provision in 40 CFR 63.693(h). However, responses to the CAA section
114 questionnaire indicate that flares are not commonly used as control
devices for this source category, and we know of only one facility that
uses a flare as a primary control device in order to comply with the
OSWRO NESHAP. In addition, none of the flare performance data used in
the draft flare technical report comes from OSWRO sources nor does it
provide any test data on non-assisted flare types, which based on
available information, is the only flare type found in the OSWRO source
category. As indicated in the EPA flare draft technical report, one of
the primary factors that affects flare performance is over-assisting
flares with too much steam or air and while this can potentially occur
in steam-assisted and air-assisted flare designs, non-assisted flare
types do not have a potential to over-assist. Thus, we have no
information to suggest that flares at OSWRO sources are achieving poor
destruction efficiency. We solicit comments on our discussion and
conclusions regarding flare performance, including additional
information on flare performance related to this source category.
[[Page 37880]]
Examples of types of information we seek from commenters regarding
flares for the OSWRO source category include: Frequency of flaring;
number and types of flares used; waste gas characteristics such as flow
rate, composition and heat content; assist gas characteristics such as
target assist gas to waste gas ratios and minimum assist gas flow
rates; use of flare gas recovery and other flare minimization
practices; and existing flare monitoring systems.
E. What compliance dates are we proposing?
Under CAA section 112(d), the proposed compliance date for new and
existing affected sources for the revised SSM requirements, electronic
reporting requirements, the revised routine maintenance provisions, the
operating and pressure release management requirements for PRDs, and
the revised requirements regarding bypasses and closure devices on
pressure tanks is the effective date of the final amendments. We are
proposing this compliance date because available information indicates
these new and revised requirements should be immediately implementable
by the facilities.
We are also proposing that for existing affected sources subject to
the OSWRO MACT standards, the compliance date for the PRD monitoring
requirements is 3 years from the effective date of the final
amendments. This time is needed regardless of whether an owner or
operator of a facility chooses to comply with the PRD monitoring
provisions by installing PRD release indicator systems and alarms,
employing parameter monitoring, routing releases to a control device,
or choosing another compliance option as permitted under the proposed
provisions. This time period will allow OSWRO facility owners and
operators to research equipment and vendors, and to purchase, install,
test and properly operate any necessary equipment by the compliance
date. For new affected sources, the proposed compliance date for PRD
monitoring requirements is the effective date of the final amendments.
Finally, we are proposing revised requirements for equipment leaks
and tanks under CAA sections 112(d)(6) and (f)(2). The compliance
deadlines for standards developed under CAA section 112(f)(2) are
addressed in CAA sections 112(f)(3) and (4). As provided in CAA Section
112(f)(4), risk standards shall not apply to existing affected sources
until 90 days after the effective date of the rule, but the
Administrator may grant a waiver for a particular source for a period
of up to 2 years after the effective date. Here, the EPA is already
aware of the steps needed for OSWRO facilities to comply with the
proposed standards for equipment leaks and tanks and to reasonably
estimate the amount of time it will take these facilities to do so.
Therefore, consistent with CAA section 112(f)(4)(B), we are proposing
that a two-year compliance period is necessary for the revised tank
requirements to allow affected facilities to research equipment and
vendors, purchase, install, test and properly operate any necessary
equipment by the compliance date. We are also proposing, consistent
with CAA section 112(f)(4)(B), that a one-year compliance period is
necessary for the revised equipment leak requirements to allow affected
facilities that are currently complying with 40 CFR part 61, subpart V
adequate time to purchase, install and test any necessary equipment and
modify their existing LDAR programs. In addition, pursuant to CAA
section 112(d)(6), we are proposing these same compliance dates for the
revised tank and equipment leak standards. For new affected sources,
the proposed compliance date for the revised tank and equipment leak
standards is the effective date of the final amendments.
V. Summary of Cost, Environmental and Economic Impacts
A. What are the affected sources?
We estimate that there are approximately 52 major source OSWRO
facilities. Based on available permit information, seven facilities are
known to be exempt from most of the rule requirements due to the low
HAP content of the off-site waste they receive or because they comply
instead with 40 CFR part 61, subpart FF, as allowed by the OSWRO
NESHAP, and they are not expected to be affected by the proposed rule
revisions. These facilities are only required to document that the
total annual quantity of the HAP contained in the off-site material
received at the plant site is less than 1 megagram per year, and they
are not subject to any other emissions limits or monitoring, reporting
or recordkeeping requirements. We are not aware of any new OSWRO
facilities that are expected to be constructed in the foreseeable
future.
B. What are the air quality impacts?
For equipment leaks, we are proposing to eliminate the option of
complying with 40 CFR part 61, subpart V, and requiring facilities in
the OSWRO source category to comply with 40 CFR part 63, subpart H,
including connector monitoring. We estimate the HAP emission reduction
for this change to be approximately 138 tpy. For tanks, we are
proposing to require tanks of certain sizes and containing materials
above certain vapor pressures to use Level 2 controls. We estimate the
HAP emission reduction for this change to be approximately 73 tpy. We
do not anticipate any HAP emission reduction from our proposed
clarification of the rule provision ``seal the open end'' (in the
context of open-ended valves and lines), clarification of the scope of
the routine maintenance provisions, or requirement to electronically
report the results of emissions testing.
For the proposed revisions to the MACT standards regarding SSM,
including monitoring of PRDs in off-site material service, we were not
able to quantify the possible emission reductions so none are included
in our assessment of air quality impacts.
Therefore, the estimated total HAP emission reductions for the
proposed rule revisions for the OSWRO source category are estimated to
be 211 tpy.
C. What are the cost impacts?
For equipment leaks, we are proposing to eliminate the option of
complying with 40 CFR part 61, subpart V, and to require facilities in
the OSWRO source category to comply with 40 CFR part 63, subpart H
(including connector monitoring). We estimate the nationwide capital
costs to be $1.9 million and the annualized costs to be $530,000. For
tanks, we are proposing to require tanks of certain sizes and
containing materials above certain vapor pressures to use Level 2
controls. We estimate the nationwide capital costs to be $76,000 and
the annualized costs to be $21,000. We do not anticipate any
quantifiable capital or annualized costs for our proposed definition of
``seal'' (in the context of open-ended valves and lines), clarification
of the scope of the routine maintenance provisions and requirement to
electronically report the results of emissions testing.
For the proposed requirements to install and operate monitors on
PRDs, we estimate the nationwide capital costs to be $1.75 million and
the annualized costs to be $250,000.
Therefore, the total capital costs for the proposed standards for
the OSWRO source category are approximately $3.7 million and the total
annualized costs are approximately $800,000.
D. What are the economic impacts?
Both the magnitude of control costs needed to comply with a
regulation and the distribution of these costs among affected
facilities can have a role in determining how the market will change in
response to that regulation. Total annualized costs for the proposed
[[Page 37881]]
amendments are estimated to be about $800,000. The average annualized
cost per facility is estimated to be about $24,000.
Without detailed industry data, it is not possible to conduct a
complete quantitative analysis of economic impacts. However, prior
analyses suggest the impacts of these proposed amendments will be
minimal. The Economic Impact Analysis for the Final OSWRO NESHAP \26\
found that demand for off-site waste services was highly inelastic.
This means that suppliers are predominantly able to pass along cost
increases to consumers through higher prices with little, if any,
decrease in the quantity of service demanded. While we do not have
specific information on prices charged or the quantity of service
provided, company revenues are a function of both these factors. The
cost-to-sales ratio is less than one quarter of one percent for all of
the 27 firms included in this analysis, suggesting any increase in
price would be minimal.
---------------------------------------------------------------------------
\26\ EPA. June 1996.
---------------------------------------------------------------------------
E. What are the benefits?
We have estimated that this action will achieve HAP emissions
reduction of 211 tons per year. The proposed standards will result in
significant reductions in the actual and MACT-allowable emissions of
HAP and will reduce the actual and potential cancer risks and non-
cancer health effects due to emissions of HAP from this source
category, as discussed in section IV.B.2. We have not quantified the
monetary benefits associated with these reductions; however, these
avoided emissions will result in improvements in air quality and
reduced negative health effects associate with exposure to air
pollution of these emissions.
VI. Request for Comments
We are soliciting comments on all aspects of this proposed action.
In addition to general comments on this proposed action, we are also
interested in any additional data that may help to improve the risk
assessments and other analyses. We are specifically interested in
receiving any improvements to the data used in the site-specific
emissions profiles used for risk modeling. Such data should include
supporting documentation in sufficient detail to allow characterization
of the quality and representativeness of the data or information.
Section VII of this preamble provides more information on submitting
data.
VII. Submitting Data Corrections
The site-specific emissions profiles used in the source category
risk and demographic analyses and instructions are available for
download on the RTR Web page at http://www.epa.gov/ttn/atw/rrisk/rtrpg.html. The data files include detailed information for each HAP
emissions release point for the facilities included in the source
category.
If you believe that the data are not representative or are
inaccurate, please identify the data in question, provide your reason
for concern and provide any ``improved'' data that you have, if
available. When you submit data, we request that you provide
documentation of the basis for the revised values to support your
suggested changes. To submit comments on the data downloaded from the
RTR page, complete the following steps:
1. Within this downloaded file, enter suggested revisions to the
data fields appropriate for that information.
2. Fill in the commenter information fields for each suggested
revision (i.e., commenter name, commenter organization, commenter email
address, commenter phone number and revision comments).
3. Gather documentation for any suggested emissions revisions
(e.g., performance test reports, material balance calculations).
4. Send the entire downloaded file with suggested revisions in
Microsoft[supreg] Access format and all accompanying documentation to
Docket ID No. EPA-HQ-OAR-2012-0360 (through one of the methods
described in the ADDRESSES section of this preamble).
5. If you are providing comments on a single facility or multiple
facilities, you need only submit one file for all facilities. The file
should contain all suggested changes for all sources at that facility.
We request that all data revision comments be submitted in the form of
updated Microsoft[supreg] Excel files that are generated by the
Microsoft[supreg] Access file. These files are provided on the RTR Web
page at: http://www.epa.gov/ttn/atw/rrisk/rtrpg.html.
VIII. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review
This action is not a ``significant regulatory action'' under the
terms of Executive Order 12866 (58 FR 51735, October 4, 1993) and is
therefore not subject to review under Executive Orders 12866 and 13563
(76 FR 3821, January 21, 2011).
B. Paperwork Reduction Act
The information collection requirements in this proposed rule have
been submitted for approval to OMB under the Paperwork Reduction Act,
44 U.S.C. 3501, et seq. The Information Collection Request (ICR)
document prepared by the EPA has been assigned the EPA ICR number
1717.10.
The information requirements are based on notification,
recordkeeping and reporting requirements in the NESHAP General
Provisions (40 CFR part 63, subpart A), which are mandatory for all
operators subject to national emissions standards. These recordkeeping
and reporting requirements are specifically authorized by CAA section
114 (42 U.S.C. 7414). All information submitted to the EPA pursuant to
the recordkeeping and reporting requirements for which a claim of
confidentiality is made is safeguarded according to agency policies set
forth in 40 CFR part 2, subpart B.
We estimate approximately 52 regulated entities are currently
subject to subpart DD; however, five facilities are only subject to
off-site waste HAP content determination requirements and are not
subject to the emissions standards and other requirements of the OSWRO
NESHAP due to the low HAP content of the off-site waste they receive.
Also, two facilities are not subject to the emissions standards and
other requirements of the OSWRO NESHAP because they comply instead with
40 CFR part 61, subpart FF, as allowed by the OSWRO NESHAP. Therefore,
we estimate that there is an annual average of 45 respondents that are
subject to the annual monitoring, reporting and recordkeeping
requirements of the regulation. This is a decrease of 191 regulated
entities from our estimate for the previous ICR (EPA ICR Number
1717.09, OMB Control Number 2060-0313) for the OSWRO source category.
The annual monitoring, reporting and recordkeeping burden for this
collection (averaged over the first 3 years after the effective date of
the standards) for the proposed amended subpart DD, including existing
rule provisions unchanged by this proposal, is estimated to be 45,147
labor hours at a cost of $2.5 million per year. This represents a
decrease of approximately $15 million and 133,000 labor hours from the
previous ICR, due primarily to the reduction in the estimated number of
regulated entities. In order to more accurately assess the change in
burden resulting from these proposed
[[Page 37882]]
amendments, we estimate that the burden for each of the 45 facilities
subject to the annual monitoring, reporting and recordkeeping
requirements of the regulations has increased by $6,000 and 92 labor
hours from the previous ICR estimate.
The total burden for the federal government (averaged over the
first 3 years after the effective date of the standard) is estimated to
be 449 labor hours per year at an annual cost of $20,200. Burden is
defined at 5 CFR 1320.3(b).
An agency may not conduct or sponsor, and a person is not required
to respond to, a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for the
EPA's regulations in 40 CFR are listed in 40 CFR part 9.
To comment on the agency's need for this information, the accuracy
of the provided burden estimates and any suggested methods for
minimizing respondent burden, the EPA has established a public docket
for this rule, which includes this ICR, under Docket ID No. EPA-HQ-OAR-
2012-0360. Submit any comments related to the ICR to the EPA and OMB.
See the ADDRESSES section at the beginning of this document for where
to submit comments to the EPA. Send comments to OMB at the Office of
Information and Regulatory Affairs, Office of Management and Budget,
725 17th Street, NW., Washington, DC 20503, Attention: Desk Office for
the EPA. Since OMB is required to make a decision concerning the ICR
between 30 and 60 days after July 2, 2014, a comment to OMB is best
assured of having its full effect if OMB receives it by August 1, 2014.
The final rule will respond to any OMB or public comments on the
information collection requirements contained in this proposal.
C. Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute unless the agency certifies that the
rule will not have a significant economic impact on a substantial
number of small entities. Small entities include small businesses,
small organizations, and small governmental jurisdictions.
For purposes of assessing the impacts of this proposed rule on
small entities, small entity is defined as: (1) A small business as
defined by the Small Business Administration's (SBA) regulations at 13
CFR 121.201; (2) a small governmental jurisdiction that is a government
of a city, county, town, school district or special district with a
population of less than 50,000; and (3) a small organization that is
any not-for-profit enterprise that is independently owned and operated
and is not dominant in its field. Facilities in this source category
are not categorized as a single industry and, as a result, cannot be
classified under a single NAICS code category. During the development
of these proposed amendments, the EPA identified 45 facilities affected
by this proposal. These 45 facilities represent 27 firms in 20
industries. These industries and the SBA size standards are shown in
Table 8.
Table 8--Industries Included in OSWRO Source Category
------------------------------------------------------------------------
NAICS Description SBA Size standard
------------------------------------------------------------------------
211111............... Crude Petroleum and 500 employees.
Natural Gas Extraction.
221310............... Water Supply and $7.0 million annual
Irrigation Systems. receipts.
237310............... Highway, Street, and $33.5 million annual
Bridge Construction. receipts.
324110............... Petroleum Refineries...... 1,500 employees.
325180............... Other Basic Inorganic 1,000 employees.
Chemical Manufacturing.
325194............... Cyclic Crude, 750 employees.
Intermediate, and Gum and
Wood Chemical
Manufacturing.
325199............... All Other Basic Organic 1,000 employees.
Chemical Manufacturing.
325211............... Plastics Material and 750 employees.
Resin Manufacturing.
327310............... Cement Manufacturing...... 750 employees.
331313............... Alumina Refining and 1,000 employees.
Primary Aluminum
Production.
333316............... Photographic and 1,000 employees.
Photocopying Equipment
Manufacturing.
336411............... Aircraft Manufacturing.... 1,500 employees.
424690............... Other Chemical and Allied 100 employees.
Products Merchant
Wholesalers.
561110............... Office Administrative $7.0 million annual
Services. receipts.
562111............... Solid Waste Collection.... $35.5 million annual
receipts.
562211............... Hazardous Waste Treatment $35.5 million annual
and Disposal. receipts.
562213............... Solid Waste Combustion and $35.5 million annual
Incinerators. receipts.
562219............... Other Nonhazardous Waste $35.5 million annual
Treatment and Disposal. receipts.
562920............... Materials Recovery $19.0 million annual
Facilities. receipts.
928110............... National Security \a\..... n/a.
------------------------------------------------------------------------
\a\ One facility is operated by the U.S. Department of Defense. Small
business size standards are not established for this sector.
After considering the economic impacts of this proposed rule on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities. For the
small business screening analysis, the EPA identified the ultimate
parent company (firm) for each facility and obtained firm-level
employment and revenues using various sources, including the American
Business Directory, Hoovers, corporate Web sites and publically
available financial reports. The screening analysis shows that four of
the 27 firms that own facilities in the OSWRO source category can be
classified as small firms using the SBA size standards for their
respective industries. Based on the sales test screening methodology,
all four firms will experience minimal impact, or a cost-to-sales ratio
of 1 percent or less. Details of this analysis can be found in the memo
``Economic Impact Analysis for Risk and Technology Review: Off-site
Waste and Recovery Operations Source Category'' in the docket.
We continue to be interested in the potential impacts of the
proposed rule on small entities and welcome comments on issues related
to such impacts.
D. Unfunded Mandates Reform Act
This rule does not contain a federal mandate that may result in
expenditures of $100 million or more for state, local and tribal
governments, in aggregate, or
[[Page 37883]]
the private sector in any one year. The total annualized cost of this
rule is estimated to be no more than $800,000 in any one year. Thus,
this proposed rule is not subject to the requirements of sections 202
or 205 of the UMRA.
This proposed rule is also not subject to the requirements of
section 203 of UMRA because it contains no regulatory requirements that
might significantly or uniquely affect small governments because it
contains no requirements that apply to such governments nor does it
impose obligations upon them.
E. Executive Order 13132: Federalism
This action does not have federalism implications. It will not have
substantial direct effects on the states, on the relationship between
the national government and the states, or on the distribution of power
and responsibilities among the various levels of government, as
specified in Executive Order 13132. None of the facilities subject to
this action are owned or operated by state governments. Thus, Executive
Order 13132 does not apply to this proposed rule.
In the spirit of Executive Order 13132, and consistent with the EPA
policy to promote communications between the EPA and State and local
governments, the EPA specifically solicits comment on this proposed
rule from state and local officials.
F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
This action does not have tribal implications, as specified in
Executive Order 13175 (65 FR 67249, November 9, 2000). There are no
Off-Site Waste Recovery Operation facilities that are owned or operated
by tribal governments. Thus, Executive Order 13175 does not apply to
this action. The EPA specifically solicits comment on this proposed
action from tribal officials.
G. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks
This action is not subject to Executive Order 13045 (62 FR 19885,
April 23, 1997) because it is not economically significant as defined
in Executive Order 12866, and because the agency does not believe the
environmental health risks or safety risks addressed by this action
present a disproportionate risk to children. Because the proposed rule
amendments would result in reduced emissions of HAP and reduced risk to
anyone exposed, the EPA believes that the proposed rule amendments
would provide additional protection to children. The EPA's risk
assessments are included in the docket for this proposed rule.
The public is invited to submit comments or identify peer-reviewed
studies and data that assess effects of early life exposure to HAP
emitted by OSWRO facilities.
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
This action is not subject to Executive Order 13211 (66 FR 28355,
May 22, 2001), because it is not a significant regulatory action under
Executive Order 12866.
I. National Technology Transfer and Advancement Act
Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (NTTAA), Public Law 104-113 (15 U.S.C. 272 note), directs
the EPA to use voluntary consensus standards (VCS) in its regulatory
activities unless to do so would be inconsistent with applicable law or
otherwise impractical. VCS are technical standards (e.g., materials
specifications, test methods, sampling procedures and business
practices) that are developed or adopted by VCS bodies. NTTAA directs
the EPA to provide Congress, through OMB, explanations when the agency
decides not to use available and applicable VCS.
This proposed rule involves technical standards. The EPA proposes
to add EPA Methods 2F and 2G to the list of methods allowed to
determine process vent stream gas volumetric flow rate. No applicable
VCS were identified for these methods. In addition, the EPA is
proposing to allow EPA Method 3A as an alternative to EPA Method 3B for
determining the oxygen concentration to use in oxygen correction
equations. While several candidate VCS were identified (ANSI/ASME PTC
19-10-1981 Part 10, ASME B133.9-1994 (2001), ISO 10396:1993 (2007), ISO
12039:2001, ASTM D5835-95 (2013), ASTM D6522-00 (2011), and CAN/CSA
Z223.2-M86 (1999)), we do not propose to use any of these standards in
this proposed rule. The use of these VCS would not be practical due to
lack of equivalency, documentation, validation data and other important
technical and policy considerations. The EPA also proposes to require
the use of EPA Method 25A to determine compliance with the control
device percent reduction requirement, if the owner or operator chooses
to measure total organic content. While the agency identified two
candidate VCS (ISO 14965:2000(E), EN 12619 (1999)) as being potentially
applicable, we do not propose to use either standard in this proposed
rule. The use of these VCS would not be practical due to the limited
measurement ranges of these methods. (For more detail, see ``Voluntary
Consensus Standard Results for NESHAP: Off-Site Waste and Recovery
Operations 40 CFR Part 63, Subpart DD'' in the docket for this proposed
rule.)
The EPA welcomes comments on this aspect of the proposed rule and,
specifically, invites the public to identify potentially-applicable VCS
and to explain why such standards should be used in this regulation.
J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations
Executive Order 12898 (59 FR 7629, February 16, 1994) establishes
federal executive policy on environmental justice. Its main provision
directs federal agencies, to the greatest extent practical and
permitted by law, to make environmental justice part of their mission
by identifying and addressing, as appropriate, disproportionately high
and adverse human health or environmental effects of their programs,
policies, and activities on minority populations and low-income
populations in the United States.
The EPA has determined that this proposed rule will not have
disproportionately high and adverse human health or environmental
effects on minority, low income or indigenous populations because it
increases the level of environmental protection for all affected
populations without having any disproportionately high and adverse
human health or environmental effects on any population, including any
minority, low income or indigenous populations.
To gain a better understanding of the source category and near
source populations, the EPA conducted a proximity analysis for OSWRO
facilities to identify any overrepresentation of minority, low income
or indigenous populations. This analysis only gives some indication of
the prevalence of sub-populations that may be exposed to air pollution
from the sources; it does not identify the demographic characteristics
of the most highly affected individuals or communities, nor does it
quantify the level of risk faced by those individuals or communities.
More information on the source category's risk can be found in section
IV of this preamble.
[[Page 37884]]
In determining the aggregate demographic makeup of the communities
near affected sources, the EPA focused on those census blocks within 3
miles of affected sources, determined the demographic composition
(e.g., race, income, etc.) of these census blocks, and compared them to
the corresponding compositions nationally. The results of this
proximity analysis show that most demographic categories were below or
within 20 percent of their corresponding national averages except for
the African American and minority populations. The African American
segment of the population within 3 miles of any source affected by this
proposed rule exceeds the national average by 166 percent, or 21
percentage points (34 percent versus 13 percent). The minority
population within 3 miles exceeds the national average by 64 percent,
or 24 percentage points, (61 percent versus 37 percent). However, as
noted previously, risks from this source category were found to be
acceptable for all populations. Additionally, the proposed changes to
the standard increase the level of environmental protection for all
affected populations by reducing emissions from equipment leaks and
tanks.
Further details concerning this analysis are presented in the
December 3, 2013 memorandum titled, Environmental Justice Review: Off-
Site Waste and Recovery Operations, RTR, a copy of which is available
in the docket for this action (EPA-HQ-OAR-2012-0360).
List of Subjects in 40 CFR Part 63
Environmental protection, Administrative practice and procedures,
Air pollution control, Hazardous substances, Reporting and
recordkeeping requirements, Volatile organic compounds.
Dated: May 30, 2014.
Gina McCarthy,
Administrator.
For the reasons stated in the preamble, the Environmental
Protection Agency (EPA) proposes to amend Title 40, chapter I, of the
Code of Federal Regulations (CFR) as follows:
PART 63--[AMENDED]
0
1. The authority citation for part 63 continues to read as follows:
Authority: 42 U.S.C. 7401 et seq.
Subpart DD--[Amended]
0
2. Section 63.680 is amended by:
0
a. Revising paragraphs (e)(1) and (2); and
0
b. Adding paragraph (g) to read as follows:
Sec. 63.680 Applicability and designation of affected sources.
* * * * *
(e) * * *
(1) Existing sources. The owner or operator of an affected source
that commenced construction or reconstruction before October 13, 1994,
must achieve compliance with the provisions of this subpart on or
before the date specified in paragraph (e)(1)(i),(ii), or (iii) of this
section as applicable to the affected source.
(i) For an affected source that commenced construction or
reconstruction before October 13, 1994 and receives off-site material
for the first time before February 1, 2000, the owner or operator of
this affected source must achieve compliance with the provisions of the
subpart (except Sec. Sec. 63.685(b)(1)(ii), 63.691(b), and
63.691(c)(3)(i) and (ii) of this subpart) on or before February 1, 2000
unless an extension has been granted by the Administrator as provided
in 40 CFR 63.6(i). These existing affected sources shall be in
compliance with the tank requirements of Sec. 63.685(b)(1)(ii) of this
subpart two years after the publication date of the final amendments on
[DATE OF PUBLICATION OF THE FINAL RULE IN THE FEDERAL REGISTER], the
equipment leak requirements of Sec. 63.691(b) of this subpart one year
after the publication date of the final amendments on [DATE OF
PUBLICATION OF THE FINAL RULE IN THE FEDERAL REGISTER], and the
pressure relief device monitoring requirements of Sec. 63.691(c)(3)(i)
and (ii) of this subpart three years after the publication date of the
final amendments on [DATE OF PUBLICATION OF THE FINAL RULE IN THE
FEDERAL REGISTER].
(ii) For an affected source that commenced construction or
reconstruction before October 13, 1994, but receives off-site material
for the first time on or after February 1, 2000, but before [DATE OF
PUBLICATION OF THE FINAL RULE IN THE FEDERAL REGISTER], the owner or
operator of the affected source must achieve compliance with the
provisions of this subpart (except Sec. Sec. 63.685(b)(1)(ii),
63.691(b), and 63.691(c)(3)(i) and (ii) of this subpart) upon the first
date that the affected source begins to manage off-site material. These
existing affected sources shall be in compliance with the tank
requirements of Sec. 63.685(b)(1)(ii) of this subpart two years after
the publication date of the final amendments on [DATE OF PUBLICATION OF
THE FINAL RULE IN THE FEDERAL REGISTER], the equipment leak
requirements of Sec. 63.691(b) of this subpart one year after the
publication date of the final amendments on [DATE OF PUBLICATION OF THE
FINAL RULE IN THE FEDERAL REGISTER], and the pressure relief device
monitoring requirements of Sec. 63.691(c)(3)(i) and (ii) of this
subpart three years after the publication date of the final amendments
on [DATE OF PUBLICATION OF THE FINAL RULE IN THE FEDERAL REGISTER].
(iii) For an affected source that commenced construction or
reconstruction before October 13, 1994, but receives off-site material
for the first time on or after [DATE OF PUBLICATION OF THE FINAL RULE
IN THE FEDERAL REGISTER], the owner or operator of the affected source
must achieve compliance with the provisions of this subpart (except
Sec. Sec. 63.685 (b)(1)(ii), 63.691(b), and 63.691(c)(3)(i) and (ii)
of this subpart) upon the first date that the affected source begins to
manage off-site material. These existing affected sources shall be in
compliance with the tank requirements of Sec. 63.685(b)(1)(ii) of this
subpart two years after the publication date of the final amendments on
[DATE OF PUBLICATION OF THE FINAL RULE IN THE FEDERAL REGISTER], the
equipment leak requirements of Sec. 63.691(b) of this subpart one year
after the publication date of the final amendments on [DATE OF
PUBLICATION OF THE FINAL RULE IN THE FEDERAL REGISTER], and the
pressure relief device monitoring requirements of Sec. 63.691(c)(3)(i)
and (ii) of this subpart three years after the publication date of the
final amendments on [DATE OF PUBLICATION OF THE FINAL RULE IN THE
FEDERAL REGISTER].
(2) New sources. The owner or operator of an affected source for
which construction or reconstruction commences on or after October 13,
1994, must achieve compliance with the provisions of this subpart
(except Sec. Sec. 63.685(b)(2), 63.691(b), and 63.691(c)(i) and (ii)
of this subpart) on or before July 1, 1996, or upon initial startup of
operations, whichever date is later as provided in 40 CFR 63.6(b). New
affected sources that commenced construction or reconstruction after
October 13, 1994, but on or before [INSERT DATE OF PUBLICATION IN THE
FEDERAL REGISTER], shall be in compliance with the tank requirements of
Sec. 63.685(b)(2) of this subpart two years after the publication date
of the final amendments, the equipment leak requirements of Sec.
63.691(b) of this
[[Page 37885]]
subpart one after the publication date of the final amendments, and the
pressure relief device monitoring requirements of Sec. 63.691(c)(i)
and (ii) of this subpart three years after the effective date of the
final amendments. New affected sources that commence construction or
reconstruction after July 2, 2014 shall be in compliance with the tank
requirements of Sec. 63.685(b)(2) of this subpart, the equipment leak
requirements of Sec. 63.691(b) of this subpart, and the pressure
relief device monitoring requirements of Sec. 63.691(c)(3)(i) and (ii)
of this subpart upon initial startup or by the effective date of the
final amendments, whichever is later.
* * * * *
(g) Applicability of this subpart. (1) The emission limitations set
forth in this subpart and the emission limitations referred to in this
subpart shall apply at all times except during periods of non-operation
of the affected source (or specific portion thereof) resulting in
cessation of the emissions to which this subpart applies.
(2) The owner or operator shall not shut down items of equipment
that are required or utilized for compliance with this subpart during
times when emissions are being routed to such items of equipment, if
the shutdown would contravene requirements of this subpart applicable
to such items of equipment.
0
3. Section 63.681 is amended by:
0
a. Adding, in alphabetical order, definitions for ``Bypass'', ``In gas/
vapor service'', ``In heavy liquid service'', ``In light liquid
service'', ``In liquid service'', ``Pressure release'', and ``Pressure
relief device or valve'';
0
b. Revising the definitions of ``Point-of-treatment'' and ``Process
vent''; and
0
c. Removing the definition of ``Safety device'' to read as follows:
Sec. 63.681 Definitions.
* * * * *
Bypass means diverting a process vent or closed vent system stream
to the atmosphere such that it does not first pass through an emission
control device.
* * * * *
In gas/vapor service means that a piece of equipment in off-site
material service contains a gas or vapor at operating conditions.
In heavy liquid service means that a piece of equipment in off-site
material service is not in gas/vapor service or in light liquid
service.
In light liquid service means that a piece of equipment in off-site
material service contains a liquid that meets the following conditions:
(1) The vapor pressure of one or more of the organic compounds is
greater than 0.3 kilopascals at 20 [deg]C,
(2) The total concentration of the pure organic compounds
constituents having a vapor pressure greater than 0.3 kilopascals at 20
[deg]C is equal to or greater than 20 percent by weight of the total
process stream, and
(3) The fluid is a liquid at operating conditions.
Note to In light liquid service. Vapor pressures may be determined
by the methods described in 40 CFR 60.485(e)(1).
In liquid service means that a piece of equipment in off-site
material service is not in gas/vapor service.
* * * * *
Point-of-treatment means a point after the treated material exits
the treatment process but before the first point downstream of the
treatment process exit where the organic constituents in the treated
material have the potential to volatilize and be released to the
atmosphere. For the purpose of applying this definition to this
subpart, the first point downstream of the treatment process exit is
not a fugitive emission point due to an equipment leak from any of the
following equipment components: Pumps, compressors, valves, connectors,
instrumentation systems, or pressure relief devices.
Pressure release means the emission of materials resulting from the
system pressure being greater than the set pressure of the pressure
relief device. This release can be one release or a series of releases
over a short time period.
Pressure relief device or valve means a safety device used to
prevent operating pressures from exceeding the maximum allowable
working pressure of the process equipment. A common pressure relief
device is a spring-loaded pressure relief valve. Devices that are
actuated either by a pressure of less than or equal to 2.5 pounds per
square inch gauge or by a vacuum are not pressure relief devices.
* * * * *
Process vent means an open-ended pipe, stack, or duct through which
a gas stream containing HAP is continuously or intermittently
discharged to the atmosphere from any of the processes listed in Sec.
63.680(c)(2)(i) through (vi) of this subpart. For the purpose of this
subpart, a process vent is none of the following: a pressure relief
device; an open-ended line or other vent that is subject to the
equipment leak control requirements under Sec. 63.691 of this subpart;
or a stack or other vent that is used to exhaust combustion products
from a boiler, furnace, process heater, incinerator, or other
combustion device.
* * * * *
0
4. Section 63.683 is revised by adding paragraphs (e) and (f) to read
as follows:
Sec. 63.683 Standards: General.
* * * * *
(e) General Duty. At all times, the owner or operator must operate
and maintain any affected source, including associated air pollution
control equipment and monitoring equipment, in a manner consistent with
safety and good air pollution control practices for minimizing
emissions. The general duty to minimize emissions does not require the
owner operator to make any further efforts to reduce emissions if
levels required by the applicable standard have been achieved.
Determination of whether a source is operating in compliance with
operation and maintenance requirements will be based on information
available to the Administrator, which may include, but is not limited
to, monitoring results, review of operation and maintenance procedures,
review of operation and maintenance records, and inspection of the
source.
(f) In addition to the cases listed in Sec. 63.695(e)(4) of this
subpart, deviation means any of the cases listed in paragraphs (f)(1)
through (6) of this section.
(1) Any instance in which an affected source subject to this
subpart, or an owner or operator of such a source, fails to meet any
requirement or obligation established by this subpart, including, but
not limited to, any emission limit, operating limit or work practice
standard.
(2) When a performance test indicates that emissions of a pollutant
in Table 1 to this subpart are exceeding the emission standard for the
pollutant specified in Table 1 to this subpart.
(3) When the average value of a monitored operating parameter,
based on the data averaging period for compliance specified in Sec.
63.695 of this subpart, does not meet the operating limit specified in
Sec. 63.693 of this subpart.
(4) When an affected source discharges directly into the atmosphere
from any of the sources specified in paragraphs (f)(4)(i) and (ii) of
this section.
(i) A pressure relief device, as defined in Sec. 63.681 of this
subpart.
(ii) A bypass, as defined in Sec. 63.681 of this subpart.
(5) Any instance in which the affected source subject to this
subpart, or an owner or operator of such a source, fails to meet any
term or condition specified
[[Page 37886]]
in paragraph (f)(5)(i) or (ii) of this section.
(i) Any term or condition that is adopted to implement an
applicable requirement in this subpart.
(ii) Any term or condition relating to compliance with this subpart
that is included in the operating permit for an affected source to
obtain such a permit.
(6) Any failure to collect required data, except for periods of
monitoring system malfunctions, repairs associated with monitoring
system malfunctions, and required monitoring system quality assurance
or quality control activities (including, as applicable, calibration
checks and required zero and span adjustments).
0
5. Section 63.684 is amended by adding paragraph (b)(5)(v) and revising
paragraph (h) to read as follows:
Sec. 63.684 Standards: Off-site Material Treatment.
* * * * *
(b) * * *
(5) * * *
(v) An incinerator, boiler, or industrial furnace for which the
owner or operator has submitted a Notification of Compliance under 40
CFR 63.1207(j) and 63.1210(d) and complies with the requirements of 40
CFR part 63, subpart EEE at all times (including times when non-
hazardous waste is being burned).
* * * * *
(h) The Administrator may at any time conduct or require that the
owner or operator conduct testing necessary to demonstrate that a
treatment process is achieving the applicable performance requirements
of this section. The testing shall be conducted in accordance with the
applicable requirements of this section. The Administrator may elect to
have an authorized representative observe testing conducted by the
owner or operator.
0
6. Section 63.685 is amended by:
0
a. Revising paragraphs (b) introductory text, (b)(1), and (b)(2);
0
b. Removing paragraph (b)(4);
0
c. Revising paragraphs (c)(1), (c)(2)(i), (c)(2)(iii)(B), (g)(2), and
(h)(3); and
0
d. Removing paragraph (i)(3) and redesignating paragraph (i)(4) as
paragraph (i)(3) to read as follows:
Sec. 63.685 Standards: Tanks.
* * * * *
(b) According to the date an affected source commenced construction
or reconstruction and the date an affected source receives off-site
material for the first time as established in Sec. 63.680(e)(i)
through (iii) of this subpart, the owner or operator shall control air
emissions from each tank subject to this section in accordance with
either paragraph (b)(1)(i) or (ii) of this section.
(1)(i) For a tank that is part of an existing affected source but
the tank is not used for a waste stabilization process as defined in
Sec. 63.681 of this subpart, the owner or operator shall determine
whether the tank is required to use either Tank Level 1 controls or
Tank Level 2 controls as specified for the tank by Table 3 of this
subpart based on the off-site material maximum HAP vapor pressure, the
tank's design capacity. The owner or operator shall control air
emissions from a tank required by Table 3 to use Tank Level 1 controls
in accordance with the requirements of paragraph (c) of this section.
The owner or operator shall control air emissions from a tank required
by Table 3 to use Tank Level 2 controls in accordance with the
requirements of paragraph (d) of this section.
(ii) For a tank that is part of an existing affected source but the
tank is not used for a waste stabilization process as defined in Sec.
63.681 of this subpart, the owner or operator shall determine whether
the tank is required to use either Tank Level 1 controls or Tank Level
2 controls as specified for the tank by Table 4 of this subpart based
on the off-site material maximum HAP vapor pressure and the tank's
design capacity. The owner or operator shall control air emissions from
a tank required by Table 4 to use Tank Level 1 controls in accordance
with the requirements of paragraph (c) of this section. The owner or
operator shall control air emissions from a tank required by Table 4 to
use Tank Level 2 controls in accordance with the requirements of
paragraph (d) of this section.
(2) For a tank that is part of a new affected source but the tank
is not used for a waste stabilization process as defined in Sec.
63.681 of this subpart, the owner or operator shall determine whether
the tank is required to use either Tank Level 1 controls or Tank Level
2 controls as specified for the tank by Table 5 of this subpart based
on the off-site material maximum HAP vapor pressure and the tank's
design capacity. The owner or operator shall control air emissions from
a tank required by Table 5 to use Tank Level 1 controls in accordance
with the requirements of paragraph (c) of this section. The owner or
operator shall control air emissions from a tank required by Table 5 to
use Tank Level 2 controls in accordance with the requirements of
paragraph (d) of this section.
* * * * *
(c) * * *
(1) The owner or operator shall determine the maximum HAP vapor
pressure for an off-site material to be managed in the tank using Tank
Level 1 controls before the first time the off-site material is placed
in the tank. The maximum HAP vapor pressure shall be determined using
the procedures specified in Sec. 63.694(j) of this subpart.
Thereafter, the owner or operator shall perform a new determination
whenever changes to the off-site material managed in the tank could
potentially cause the maximum HAP vapor pressure to increase to a level
that is equal to or greater than the maximum HAP vapor pressure limit
for the tank design capacity category specified in Table 3, Table 4, or
Table 5 of this subpart, as applicable to the tank.
(2) * * *
(i) The owner or operator controls air emissions from the tank in
accordance with the provisions specified in subpart OO of 40 CFR part
63--National Emission Standards for Tanks--Level 1, except that 40 CFR
63.902(c)(2) and (3) shall not apply for the purposes of this subpart.
* * * * *
(iii) * * *
(B) At all other times, air emissions from the tank must be
controlled in accordance with the provisions specified in 40 CFR part
67, subpart OO--National Emission Standards for Tanks--Level 1, except
that 40 CFR 63.902(c)(2) and (3) shall not apply for the purposes of
this subpart.
* * * * *
(g) * * *
(2) Whenever an off-site material is in the tank, the fixed roof
shall be installed with each closure device secured in the closed
position and the vapor headspace underneath the fixed roof vented to
the control device except that to the control device except that
venting to the control device is not required, and opening of closure
devices or removal of the fixed roof is allowed at the following times:
(i) To provide access to the tank for performing routine
inspection, maintenance, or other activities needed for normal
operations. Examples of such activities include those times when a
worker needs to open a port to sample liquid in the tank, or when a
worker needs to open a hatch to maintain or repair equipment. Following
completion of the activity, the owner or operator shall promptly secure
the closure device in the closed position or reinstall the cover, as
applicable, to the tank.
(ii) To remove accumulated sludge or other residues from the bottom
of the tank.
* * * * *
[[Page 37887]]
(h) * * *
(3) Whenever an off-site material is in the tank, the tank shall be
operated as a closed system that does not vent to the atmosphere except
at those times when purging of inerts from the tank is required and the
purge stream is routed to a closed-vent system and control device
designed and operated in accordance with the requirements of Sec.
63.693 of this subpart.
(i) * * *
(3) The owner or operator shall inspect and monitor the closed-vent
system and control device as specified in Sec. 63.693.
0
7. Section 63.686 is amended by revising paragraphs (b)(1) through (3)
to read as follows:
Sec. 63.686 Standards: Oil-water and organic water separators.
* * * * *
(b) * * *
(1) A floating roof in accordance with all applicable provisions
specified in 40 CFR part 63, subpart VV--National Emission Standards
for Oil-Water Separators and Organic-Water Separators, except that
Sec. Sec. 63.1043(c)(2), 63.1044(c)(2), and 63.1045(b)(3)(i) shall not
apply for the purposes of this subpart. For portions of the separator
where it is infeasible to install and operate a floating roof, such as
over a weir mechanism, the owner or operator shall comply with the
requirements specified in paragraph (b)(2) of this section.
(2) A fixed-roof that is vented through a closed-vent system to a
control device in accordance with all applicable provisions specified
in 40 CFR part 63, subpart VV--National Emission Standards for Oil-
Water Separators and Organic-Water Separators, except that Sec. Sec.
63.1043(c)(2), 63.1044(c)(2), and 63.1045(b)(3)(i) shall not apply for
the purposes of this subpart.
(3) A pressurized separator that operates as a closed system in
accordance with all applicable provisions specified in 40 CFR part 63,
subpart VV--National Emission Standards for Oil-Water Separators and
Organic-Water Separators, except that Sec. Sec. 63.1043(c)(2),
63.1044(c)(2), and 63.1045(b)(3)(i) shall not apply for the purposes of
this subpart.
0
8. Section 63.687 is amended by revising paragraphs (b)(1) and (2) to
read as follows:
Sec. 63.687 Standards: Surface impoundments.
* * * * *
(b) * * *
(1) A floating membrane cover in accordance with the applicable
provisions specified in 40 CFR part 63, subpart QQ--National Emission
Standards for Surface Impoundments, except that Sec. Sec. 63.942(c)(2)
and (3) and 63.943(c)(2) shall not apply for the purposes of this
subpart; or
(2) A cover that is vented through a closed-vent system to a
control device in accordance with all applicable provisions specified
in 40 CFR part 63, subpart QQ--National Emission Standards for Surface
Impoundments, except that Sec. Sec. 63.942(c)(2) and (3) and
63.943(c)(2) shall not apply for the purposes of this subpart.
0
9. Section 63.688 is amended by revising paragraphs (b)(1)(i),
(b)(1)(ii), and (b)(3)(i) to read as follows:
Sec. 63.688 Standards: Containers.
* * * * *
(b) * * *
(1) * * *
(i) The owner or operator controls air emissions from the container
in accordance with the standards for Container Level 1 controls as
specified in 40 CFR part 63, subpart PP--National Emission Standards
for Containers, except that Sec. Sec. 63.922(d)(4) and (5) and
63.923(d)(4) and (5) shall not apply for the purposes of this subpart.
(ii) As an alternative to meeting the requirements in paragraph
(b)(1)(i) of this section, an owner or operator may choose to control
air emissions from the container in accordance with the standards for
either Container Level 2 controls or Container Level 3 controls as
specified in subpart PP of 40 CFR part 63--National Emission Standards
for Containers, except that Sec. Sec. 63.922(d)(4) and (5) and
63.923(d)(4) and (5) shall not apply for the purposes of this subpart.
* * * * *
(3) * * *
(i) The owner or operator controls air emissions from the container
in accordance with the standards for Container Level 2 controls as
specified in 40 CFR part 63, subpart PP--National Emission Standards
for Containers, except that Sec. Sec. 63.922(d)(4) and (5) and
63.923(d)(4) and (5) shall not apply for the purposes of this subpart.
* * * * *
0
10. Section 63.689 is amended by revising paragraph (d)(5) to read as
follows:
Sec. 63.689 Standards: Transfer systems.
* * * * *
(d) * * *
(5) Whenever an off-site material is in the transfer system, the
cover shall be installed with each closure device secured in the closed
position, except the opening of closure devices or removal of the cover
is allowed to provide access to the transfer system for performing
routine inspection, maintenance, repair, or other activities needed for
normal operations. Examples of such activities include those times when
a worker needs to open a hatch or remove the cover to repair conveyance
equipment mounted under the cover or to clear a blockage of material
inside the system. Following completion of the activity, the owner or
operator shall promptly secure the closure device in the closed
position or reinstall the cover, as applicable.
* * * * *
0
11. Section 63.691 is amended by:
0
a. Revising paragraph (b); and
0
b. Adding paragraph (c) to read as follows:
Sec. 63.691 Standards: Equipment leaks.
* * * * *
(b) According to the date an affected source commenced construction
or reconstruction and the date an affected source receives off-site
material for the first time, as established in Sec. 63.680(e)(i)
through (iii) of this subpart, the owner or operator shall control the
HAP emitted from equipment leaks in accordance with the applicable
provisions specified in either paragraph (b)(1) or (2) of this section.
(1)(i) The owner or operator controls the HAP emitted from
equipment leaks in accordance with Sec. Sec. 61.241 through 61.247 in
40 CFR part 61, subpart V--National Emission Standards for Equipment
Leaks, with the difference noted in paragraphs (b)(1)(iii) and (iv) of
this section for the purposes of this subpart; or
(ii) The owner or operator controls the HAP emitted from equipment
leaks in accordance with Sec. Sec. 63.161 through 63.182 in 40 CFR
part 63, subpart H--National Emission Standards for Organic Hazardous
Air Pollutants from Equipment Leaks, with the differences noted in
paragraphs (b)(2)(i) through (iv) of this section for the purposes of
this subpart.
(iii) On or after [DATE OF PUBLICATION OF THE FINAL RULE AMENDMENTS
IN THE FEDERAL REGISTER], for the purpose of complying with the
requirements of 40 CFR 61.242-6(a)(2), the open end is sealed when
instrument monitoring of the open-ended valve or line conducted
according to Method 21 of 40 CFR part 60, appendix A indicates no
readings of 500 ppm or greater.
(iv) On or after [DATE OF PUBLICATION OF THE FINAL RULE IN THE
FEDERAL REGISTER], for the purpose of complying with the requirements
of 40 CFR 61.242-6(d),
[[Page 37888]]
open-ended valves or lines in an emergency shutdown system which are
designed to open automatically in the event of a process upset and that
are exempt from the requirements in 40 CFR 61.242-6(a), (b), and (c)
must comply with the requirements in Sec. 63.693(c)(2) of this
subpart.
(2) The owner or operator controls the HAP emitted from equipment
leaks in accordance with Sec. Sec. 63.161 through Sec. 63.183 in 40
CFR part 63, subpart H--National Emission Standards for Organic
Hazardous Air Pollutants for Equipment Leaks, with the differences
noted in paragraphs (b)(2)(i) through (v) of this section for the
purposes of this subpart.
(i) For each valve in gas/vapor or in light liquid service, as
defined in Sec. 63.681 of this subpart, that is part of an affected
source under this subpart, an instrument reading that defines a leak is
500 ppm or greater as detected by Method 21 of 40 CFR part 60, appendix
A.
(ii) For each pump in light liquid service, as defined in Sec.
63.681 of this subpart, that is part of an affected source under this
subpart, an instrument reading that defines a leak is 1,000 ppm or
greater as detected by Method 21 of 40 CFR part 60, appendix A. Repair
is not required unless an instrument reading of 2,000 ppm or greater is
detected.
(iii) On or after [DATE OF PUBLICATION OF THE FINAL RULE IN THE
FEDERAL REGISTER], for the purpose of complying with the requirements
of 40 CFR 63.167(a)(2), the open end is sealed when instrument
monitoring of the open-ended valve or line conducted according to
Method 21 of 40 CFR part 60, appendix A indicates no readings of 500
ppm or greater.
(iv) On or after [DATE OF PUBLICATION OF THE FINAL RULE IN THE
FEDERAL REGISTER], for the purpose of complying with the requirements
of 40 CFR 63.167(d), open-ended valves or lines in an emergency
shutdown system which are designed to open automatically in the event
of a process upset and that are exempt from the requirements in 40 CFR
63.167(a), (b), and (c) must comply with the requirements in Sec.
63.693(c)(2) of this subpart.
(v) For the purposes of this subpart, the pressure relief device
requirements of Sec. 63.691(c) of this subpart rather than those of 40
CFR 63.165 shall apply.
(c) Requirements for pressure relief devices. Except as provided in
paragraph (c)(4) of this section, the owner or operator must comply
with the requirements specified in paragraphs (c)(1) through (3) of
this section for pressure relief devices in off-site material service.
(1) Operating requirements. Except during a pressure release event,
operate each pressure relief device in off-site material gas or vapor
service with an instrument reading of less than 500 ppm above
background as detected by Method 21 of 40 CFR part 60, appendix A.
(2) Pressure release requirements. For pressure relief devices in
off-site material gas or vapor service, the owner or operator must
comply with either paragraph (c)(2)(i) or (ii) of this section
following a pressure release, as applicable.
(i) If the pressure relief device does not consist of or include a
rupture disk, the pressure relief device shall be returned to a
condition indicated by an instrument reading of less than 500 ppm above
background, as detected by Method 21 of 40 CFR part 60, appendix A, no
later than 5 calendar days after the pressure release device returns to
off-site material service following a pressure release, except as
provided in 40 CFR 63.171.
(ii) If the pressure relief device consists of or includes a
rupture disk, except as provided in 40 CFR 63.171, install a
replacement disk as soon as practicable but no later than 5 calendar
days after the pressure release.
(3) Pressure release management. Except as provided in paragraph
(c)(4) of this section, emissions of HAP listed in Table 1 of this
subpart may not be discharged directly to the atmosphere from pressure
relief devices in off-site material service, and according to the date
an affected source commenced construction or reconstruction and the
date an affected source receives off-site material for the first time,
as established in Sec. 63.680(e)(1)(i) through (iii) of this subpart,
the owner or operator must comply with the requirements specified in
paragraphs (c)(3)(i) and (ii) of this section for all pressure relief
devices in off-site material service.
(i) The owner or operator must equip each pressure relief device in
off-site material service with a device(s) or use a monitoring system.
The device or monitoring system may be either specific to the pressure
release device itself or may be associated with the process system or
piping, sufficient to indicate a pressure release to the atmosphere.
Examples of these types of devices or monitoring systems include, but
are not limited to, a rupture disk indicator, magnetic sensor, motion
detector on the pressure relief valve stem. The devices or monitoring
systems must be capable of meeting the requirements specified in
paragraphs (c)(3)(i)(A) through (C) of this section.
(A) Identifying the pressure release;
(B) Recording the time and duration of each pressure release; and
(C) Notifying operators immediately that a pressure release is
occurring.
(ii) If any pressure relief device in off-site material service
releases directly to the atmosphere as a result of a pressure release
event, the owner or operator must calculate the quantity of HAP listed
in Table 1 of this subpart released during each pressure release event
and report this quantity as required in Sec. 63.697(b)(5).
Calculations may be based on data from the pressure relief device
monitoring alone or in combination with process parameter monitoring
data and process knowledge.
(4) Pressure relief devices routed to a drain system, process or
control device. If a pressure relief device in off-site material
service is designed and operated to route all pressure releases through
a closed vent system to a drain system, process or control device,
paragraphs (c)(1), (2), and (3) of this section do not apply. The
closed vent system and the process or control device (if applicable)
must meet the requirements of Sec. 63.693 of this subpart. The drain
system (if applicable) must meet the requirements of Sec. 63.689 of
this subpart.
0
12. Section 63.693 is amended by:
0
a. Revising paragraphs (b)(3) and (8), (c)(1)(ii), and (c)(2)
introductory text;
0
b. Adding paragraph (c)(2)(iii); and
0
c. Revising paragraphs (f)(1)(i)(B) and (ii)(B) and (g)(1)(v) to read
as follows:
Sec. 63.693 Standards: Closed-vent systems and control devices.
* * * * *
(b) * * *
(3) Whenever gases or vapors containing HAP are routed from a tank
through a closed-vent system connected to a control device used to
comply with the requirements of Sec. 63.685(b)(1), (2), or (3) of this
subpart, the control device must be operating except as provided for in
paragraphs (b)(3)(i) and (ii) of this section.
(i) The control device may only be bypassed for the purpose of
performing planned routine maintenance of the closed-vent system or
control device in situations when the routine maintenance cannot be
performed during periods that tank emissions are vented to the control
device.
(ii) On an annual basis, the total time that the closed-vent system
or control device is bypassed to perform routine maintenance shall not
exceed 240 hours per each calendar year.
* * * * *
[[Page 37889]]
(8) In the case when an owner or operator chooses to use a design
analysis to demonstrate compliance of a control device with the
applicable performance requirements specified in this section as
provided for in paragraphs (d) through (g) of this section, the
Administrator may require that the design analysis be revised or
amended by the owner or operator to correct any deficiencies identified
by the Administrator. If the owner or operator and the Administrator do
not agree on the acceptability of using the design analysis (including
any changes required by the Administrator) to demonstrate that the
control device achieves the applicable performance requirements, then
the disagreement must be resolved using the results of a performance
test conducted by the owner or operator in accordance with the
requirements of Sec. 63.694(l) of this subpart. The Administrator may
choose to have an authorized representative observe the performance
test conducted by the owner or operator. Should the results of this
performance test not agree with the determination of control device
performance based on the design analysis, then the results of the
performance test will be used to establish compliance with this
subpart.
* * * * *
(c) * * *
(1) * * *
(ii) A closed-vent system that is designed to operate at a pressure
below atmospheric pressure. The system shall be equipped with at least
one pressure gauge or other pressure measurement device that can be
read from a readily accessible location to verify that negative
pressure is being maintained in the closed-vent system when the control
device is operating.
(2) In situations when the closed-vent system includes bypass
devices that could be used to divert a vent stream from the closed-vent
system to the atmosphere at a point upstream of the control device
inlet, each bypass device must be equipped with either a flow indicator
as specified in paragraph (c)(2)(i) of this section or a seal or
locking device as specified in paragraph (c)(2)(ii) of this section,
except as provided for in paragraph (c)(2)(iii) of this section:
* * * * *
(iii) Equipment needed for safety reasons, including low leg
drains, open-ended valves and lines not in emergency shutdown systems,
and pressure relief devices subject to the requirements of Sec.
63.691(c) of this subpart are not subject to the requirements of
paragraphs (c)(2)(i) and (ii) of this section.
* * * * *
(f) * * *
(1) * * *
(i) * * *
(B) To achieve a total incinerator outlet concentration for the
TOC, less methane and ethane, of less than or equal to 20 ppmv on a dry
basis corrected to 3 percent oxygen.
(ii) * * *
(B) To achieve a total incinerator outlet concentration for the
HAP, listed in Table 1 of this subpart, of less than or equal to 20
ppmv on a dry basis corrected to 3 percent oxygen.
* * * * *
(g) * * *
(1) * * *
(v) Introduce the vent stream to a boiler or process heater for
which the owner or operator either has been issued a final permit under
40 CFR part 270 and complies with the requirements of 40 CFR part 266,
subpart H; or has certified compliance with the interim status
requirements of 40 CFR part 266, subpart H; or has submitted a
Notification of Compliance under 40 CFR 63.1207(j) and 63.1210(d) and
complies with the requirements of 40 CFR part 63, subpart EEE at all
times (including times when non-hazardous waste is being burned).
* * * * *
0
13. Section 63.694 is amended by revising paragraphs (b)(3)(iv),
(f)(1), (i)(1), (j)(3), (k)(3), (l) introductory text, (l)(3)
introductory text, (l)(3)(i), (l)(3)(ii)(B), (l)(4) introductory text,
(l)(4)(i), (l)(4)(ii)(A) and (B), (l)(4)(iii)(A), and (m)(2) and (3) to
read as follows:
Sec. 63.694 Testing methods and procedures.
* * * * *
(b) * * *
(3) * * *
(iv) In the event that the Administrator and the owner or operator
disagree on a determination of the average VOHAP concentration for an
off-site material stream using knowledge, then the results from a
determination of VOHAP concentration using direct measurement as
specified in paragraph (b)(2) of this section shall be used to
establish compliance with the applicable requirements of this subpart.
The Administrator may perform or require that the owner or operator
perform this determination using direct measurement.
(f) * * *
(1) The actual HAP mass removal rate (MR) shall be determined based
on results for a minimum of three consecutive runs. The sampling time
for each run shall be at least 1 hour.
* * * * *
(i) * * *
(1) The actual HAP mass removal rate (MRbio) shall be
determined based on results for a minimum of three consecutive runs.
The sampling time for each run shall be at least 1 hour.
* * * * *
(j) * * *
(3) Use of knowledge to determine the maximum HAP vapor pressure of
the off-site material. Documentation shall be prepared and recorded
that presents the information used as the basis for the owner's or
operator's knowledge that the maximum HAP vapor pressure of the off-
site material is less than the maximum vapor pressure limit listed in
Table 3, Table 4, or Table 5 of this subpart for the applicable tank
design capacity category. Examples of information that may be used
include: the off-site material is generated by a process for which at
other locations it previously has been determined by direct measurement
that the off-site material maximum HAP vapor pressure is less than the
maximum vapor pressure limit for the appropriate tank design capacity
category. In the event that the Administrator and the owner or operator
disagree on a determination of the maximum HAP vapor pressure for an
off-site material stream using knowledge, then the results from a
determination of HAP vapor pressure using direct measurement as
specified in paragraph (j)(2) of this section shall be used to
establish compliance with the applicable requirements of this subpart.
The Administrator may perform or require that the owner or operator
perform this determination using direct measurement.
(k) * * *
(3) The detection instrument shall meet the performance criteria of
Method 21 of 40 CFR part 60, appendix A, except the instrument response
factor criteria in section 8.1.1 of Method 21 shall be for the weighted
average composition of the organic constituents in the material placed
in the unit at the time of monitoring, not for each individual organic
constituent.
* * * * *
(l) Control device performance test procedures. Performance tests
shall be conducted under such conditions as the Administrator specifies
to the owner or operator based on representative performance of the
affected source for the period being tested. Representative conditions
exclude periods of startup and shutdown. The owner or operator may not
conduct performance tests
[[Page 37890]]
during periods of malfunction. The owner or operator must record the
process information that is necessary to document operating conditions
during the test and include in such record an explanation to support
that such conditions represent normal operation. Upon request, the
owner or operator shall make available to the Administrator such
records as may be necessary to determine the conditions of performance
tests.
* * * * *
(3) To determine compliance with the control device percent
reduction requirement, the owner or operator shall use Method 18 of 40
CFR part 60, appendix A to measure the HAP in Table 1 of this subpart
or Method 25A of 40 CFR part 60, appendix A to measure TOC. Method 18
may be used to measure methane and ethane, and the measured
concentration may be subtracted from the Method 25A measurement.
Alternatively, any other method or data that has been validated
according to the applicable procedures in Method 301 in 40 CFR part 63,
appendix A may be used. The following procedures shall be used to
calculate percent reduction efficiency:
(i) A minimum of three sample runs must be performed. The minimum
sampling time for each run shall be 1 hour. For Method 18, either an
integrated sample or a minimum of four grab samples shall be taken. If
grab sampling is used, then the samples shall be taken at approximately
equal intervals in time such as 15 minute intervals during the run.
(ii) * * *
(B) When the TOC mass rate is calculated, the average concentration
reading (minus methane and ethane) measured by Method 25A of 40 CFR
part 60, appendix A shall be used in the equation in paragraph
(l)(3)(ii)(A) of this section.
* * * * *
(4) To determine compliance with the enclosed combustion device
total HAP concentration limit of this subpart, the owner or operator
shall use Method 18 of 40 CFR part 60, appendix A to measure the total
HAP in Table 1 of this subpart of Method 25A of 40 CFR part 60,
appendix A to measure TOC. Method 18 may be used to measure methane and
ethane and the measured concentration may be subtracted from the Method
25A measurement. Alternatively, any other method or data that has been
validated according to Method 301 in appendix A of this part, may be
used. The following procedures shall be used to calculate parts per
million by volume concentration, corrected to 3 percent oxygen:
(i) A minimum of three sample runs must be performed. The minimum
sampling time for each run shall be 1 hour. For Method 18, either an
integrated sample or a minimum of four grab samples shall be taken. If
grab sampling is used, then the samples shall be taken at approximately
equal intervals in time, such as 15 minute intervals during the run.
(ii) * * *
(A) The TOC concentration (CTOC) is the average
concentration readings provided by Method 25 A of 40 CFR part 60,
appendix A, minus the concentration of methane and ethane.
(B) The total HAP concentration (CHAP) shall be computed
according to the following equation:
[GRAPHIC] [TIFF OMITTED] TP02JY14.002
Where:
CHAP = Total concentration of HAP compounds listed in
Table 1 of this subpart, dry basis, parts per million by volume.
Cij = Concentration of sample components j of sample i,
dry basis, parts per million by volume.
n = Number of components in the sample.
x = Number of samples in the sample run.
(iii) * * *
(A) The emission rate correction factor or excess air, integrated
sampling and analysis procedures of Method 3B of 40 CFR part 60,
appendix A shall be used to determine the oxygen concentration
(%O2dry). Alternatively, the owner or operator may use
Method 3A of 40 CFR part 60, appendix A to determine the oxygen
concentration. The samples shall be collected during the same time that
the samples are collected for determining TOC concentration or total
HAP concentration.
* * * * *
(m) * * *
(2) No traverse site selection method is needed for vents smaller
than 0.10 meter in diameter. For vents smaller than 0.10 meter in
diameter, sample at the center of the vent.
(3) Process vent stream gas volumetric flow rate must be determined
using Method 2, 2A, 2C, 2D, 2F, or 2G of 40 CFR part 60, appendix A, as
appropriate.
* * * * *
0
14. Section 63.695 is amended by:
0
a. Revising paragraph (a) introductory text;
0
b. Adding paragraph (a)(5);
0
c. Revising paragraphs (e)(4) and (5); and
0
d. Removing paragraphs (e)(6) and (7) to read as follows:
Sec. 63.695 Inspection and monitoring requirements.
(a) The owner or operator must install, calibrate, maintain, and
operate all monitoring system components according to Sec. Sec. 63.8
of this part, 63.684(e), 63.693(d)(3), (e)(3), (f)(3), (g)(3), and
(h)(3) of this subpart, and paragraph (a)(5) of this section and
perform the inspection and monitoring procedures specified in
paragraphs (a)(1) through (4) of this section.
* * * * *
(5)(i) Except for periods of monitoring system malfunctions,
repairs associated with monitoring system malfunctions and required
monitoring system quality assurance or quality control activities
(including, as applicable, calibration checks and required zero and
span adjustments), the owner or operator must operate the continuous
monitoring system at all times the affected source is operating. A
monitoring system malfunction is any sudden, infrequent, not reasonably
preventable failure of the monitoring system to provide data.
Monitoring system failures that are caused in part by poor maintenance
or careless operation are not malfunctions. The owner or operator is
required to complete monitoring system repairs in response to
monitoring system malfunctions and to return them monitoring system to
operation as expeditiously as practicable.
(ii) The owner or operator may not use data recorded during
monitoring system malfunctions, repairs associated with monitoring
system malfunctions, or required monitoring system quality assurance or
control activities in calculations used to report emissions or
operating levels. The owner or operator must use all the data collected
during all other required data collection periods in assessing the
operation of the control device and associated control system. The
owner or operator must report any periods for which the monitoring
system failed to collect required data.
* * * * *
(e) * * *
(4) A deviation for a given control device is determined to have
occurred when the monitoring data or lack of monitoring data result in
any one of the criteria specified in paragraphs (e)(4)(i) through (iii)
of this section being met. When multiple operating parameters are
monitored for the same control device and during the same operating day
more than one of these operating parameters meets a deviation criterion
specified in paragraphs (e)(4)(i) through (iii) of this
[[Page 37891]]
section, then a single deviation is determined to have occurred for the
control device for that operating day.
(i) A deviation occurs when the daily average value of a monitored
operating parameter is less than the minimum operating parameter limit
(or, if applicable, greater than the maximum operating parameter limit)
established for the operating parameter in accordance with the
requirements of paragraph (e)(3) of this section.
(ii) A deviation occurs when the period of control device operation
is 4 hours or greater in an operating day and the monitoring data are
insufficient to constitute a valid hour of data for at least 75 percent
of the operating hours. Monitoring data are insufficient to constitute
a valid hour of data if measured values are unavailable for any of the
15-minute periods within the hour.
(iii) A deviation occurs when the period of control device
operation is less than 4 hours in an operating day and more than 1 of
the hours during the period does not constitute a valid hour of data
due to insufficient monitoring data. Monitoring data are insufficient
to constitute a valid hour of data if measured values are unavailable
for any of the 15-minute periods within the hour.
(5) For each deviation, except when the deviation occurs during
periods of non-operation of the unit or the process that is vented to
the control device (resulting in cessation of HAP emissions to which
the monitoring applies), the owner or operator shall be deemed to have
failed to have applied control in a manner that achieves the required
operating parameter limits. Failure to achieve the required operating
parameter limits is a violation of this standard.
* * * * *
0
15. Section 63.696 is amended by revising paragraph (h) and adding
paragraphs (i) and (j) to read as follows:
Sec. 63.696 Recordkeeping requirements.
* * * * *
(h) An owner or operator shall record the malfunction information
specified in paragraphs (h)(1) through (3) of this section.
(1) In the event that an affected unit fails to meet an applicable
standard, record the number of failures. For each failure record the
date, time and duration of the failure.
(2) For each failure to meet an applicable standard, record and
retain a list of the affected sources or equipment, an estimate of the
volume of each regulated pollutant emitted over any emission limit and
a description of the method used to estimate the emissions.
(3) Record actions taken to minimize emissions in accordance with
Sec. 63.683(e) of this subpart and any corrective actions taken to
return the affected unit to its normal or usual manner of operation.
(i) For pressure relief devices in off-site material service, keep
records of the information specified in paragraphs (i)(1) through (5)
of this section, as applicable.
(1) A list of identification numbers for pressure relief devices
that the owner or operator elects to route emissions through a closed-
vent system to a control device, process or drain system under the
provisions in Sec. 63.691(c)(4) of this subpart.
(2) A list of identification numbers for pressure relief devices
that do not consist of or include a rupture disk, subject to the
provisions in Sec. 63.691(c)(2)(i) of this subpart.
(3) A list of identification numbers for pressure relief devices
equipped with rupture disks, subject to the provisions in Sec.
63.691(c)(2)(ii) of this subpart.
(4) The dates and results of the Method 21 of 40 CFR part 60,
appendix A, monitoring following a pressure release for each pressure
relief device subject to the provisions in Sec. 63.691(c)(2)(i) of
this subpart. The results of each monitoring event shall include:
(i) The measured background level.
(ii) The maximum instrument reading measured at each pressure
relief device.
(5) For pressure relief devices in off-site material service
subject to Sec. 63.691(c)(3) of this subpart, keep records of each
pressure release to the atmosphere, including the following
information:
(i) The source, nature, and cause of the pressure release.
(ii) The date, time, and duration of the pressure release.
(iii) An estimate of the quantity of HAP listed in Table 1 of this
subpart emitted during the pressure release and the calculations used
for determining this quantity.
(iv) The actions taken to prevent this pressure release.
(v) The measures adopted to prevent future such pressure releases.
(j)(1) For pressure tank closure devices, as specified in Sec.
63.685(h)(2) of this subpart, keep records of each release to the
atmosphere, including the information specified in paragraphs (j)(3)
through (7) of this section.
(2) For each closed vent system that includes bypass devices that
could divert a stream away from the control device and into the
atmosphere, as specified in Sec. 63.693(c)(2) of this subpart, and
each open-ended valve or line in an emergency shutdown system which is
designed to open automatically in the event of a process upset, as
specified in 40 CFR 63.167(d) or 40 CFR 61.242-6(d), keep records of
each release to the atmosphere, including the information specified in
paragraphs (j)(3) through (9) of this section.
(3) The source, nature, and cause of the release.
(4) The date, time, and duration of the release.
(5) An estimate of the quantity of HAP listed in Table 1 of this
subpart emitted during the release and the calculations used for
determining this quantity.
(6) The actions taken to prevent this release.
(7) The measures adopted to prevent future such release.
(8) Hourly records of whether the bypass flow indicator specified
under Sec. 63.693(c)(2) of this subpart was operating and whether a
diversion was detected at any time during the hour, as well as records
of the times of all periods when the vent stream is diverted from the
control device or the flow indicator is not operating.
(9) Where a seal mechanism is used to comply with Sec.
63.693(c)(2) of this subpart, hourly records of flow are not required.
In such cases, the owner or operator shall record that the monthly
visual inspection of the seals or closure mechanism has been done, and
shall record the duration of all periods when the seal mechanism is
broken, the bypass line valve position has changed, or the key for a
lock-and-key type lock has been checked out, and records of any car-
seal that has broken.
0
16. Section 63.697 is amended by:
0
a. Revising paragraph (a) introductory text, adding paragraphs
(a)(1)(i) and (ii) and (a)(3);
0
b. Revising paragraph (b)(3) and (4); and
0
c. Adding paragraphs (b)(5) and (6) to read as follows:
Sec. 63.697 Reporting requirements.
(a) Each owner or operator of an affected source subject to this
subpart must comply with the notification requirements specified in
paragraph (a)(1) of this section and the reporting requirements
specified in paragraphs (a)(2) and (3) of this section.
(1) * * *
(i) For pressure relief devices in off-site material service
subject to the requirements of Sec. 63.691(c) of this subpart, the
owner or operator must submit the information listed in paragraph
(a)(1)(ii) of this section in the notification of compliance status
[[Page 37892]]
required under Sec. 63.9(h) of this part within 150 days after the
first applicable compliance date for pressure relief device monitoring.
(ii) For pressure relief devices in off-site material service, a
description of the device or monitoring system to be implemented,
including the pressure relief devices and process parameters to be
monitored (if applicable), a description of the alarms or other methods
by which operators will be notified of a pressure release, and a
description of how the owner or operator will determine the information
to be recorded under Sec. 63.696(i)(5)(ii) through (iii) of this
subpart (i.e., the duration of the pressure release and the methodology
and calculations for determining the quantity of HAP listed in Table 1
of this subpart emitted during the pressure release).
* * * * *
(3) Electronic reporting. Within 60 days after the date of
completing each performance test (as defined in Sec. 63.2 of this
part) required by this subpart, the owner or operator must submit the
results of the performance test according to the manner specified by
either paragraph (a)(3)(i) or (ii) of this section.
(i) For data collected using test methods supported by the EPA's
Electronic Reporting Tool (ERT) as listed on the EPA's ERT Web site
(http://www.epa.gov/ttn/chief/ert/index.html), the owner or operator
must submit the results of the performance test to the EPA via the
Compliance and Emissions Data Reporting Interface (CEDRI) accessed
through the EPA's Central Data Exchange (CDX) (http://cdx.epa.gov/epa_home.asp). Performance test data must be submitted in a file format
generated through the use of the EPA's ERT. Owners or operators who
claim that some of the performance test information being submitted is
confidential business information (CBI) must submit a complete file
generated through the use of the EPA's ERT, including information
claimed to be CBI, on a compact disc, flash drive, or other commonly
used electronic storage media to the EPA. The electronic media must be
clearly marked as CBI and mailed to U.S. EPA/OAPQS/CORE CBI Office,
Attention: WebFIRE Administrator, MD C404-02, 4930 Old Page Rd.,
Durham, NC 27703. The same ERT file with the CBI omitted must be
submitted to the EPA via the EPA's CDX as described earlier in this
paragraph (a)(3)(i).
(ii) For data collected using test methods that are not supported
by the EPA's ERT as listed on the EPA's ERT Web site, the owner or
operator must submit the results of the performance test to the
Administrator at the appropriate address listed in 40 CFR 60.4.
(b) * * *
(3) Reports of malfunctions. If a source fails to meet an
applicable standard, report such events in the Periodic Report. Report
the number of failures to meet an applicable standard. For each
instance, report the date, time and duration of each failure. For each
failure the report must include a list of the affected sources or
equipment, an estimate of the volume of each regulated pollutant
emitted over any emission limit, and a description of the method used
to estimate the emissions.
(4) A summary report specified in Sec. 63.10(e)(3) of this part
shall be submitted on a semiannual basis (i.e., once every 6-month
period). The summary report must include a description of all
deviations as defined in Sec. 63.695(e) of this subpart that have
occurred during the 6-month reporting period. For each deviation caused
when the daily average value of a monitored operating parameter is less
than the minimum operating parameter limit (or, if applicable, greater
than the maximum operating parameter limit), the report must include
the daily average values of the monitored parameter, the applicable
operating parameter limit, and the date and duration of the period that
the deviation occurred. For each deviation caused by lack of monitoring
data, the report must include the date and duration of period when the
monitoring data were not collected and the reason why the data were not
collected.
(5) For pressure relief devices in off-site material service
subject to Sec. 63.691(c) of this subpart, Periodic Reports must
include the information specified in paragraphs (b)(5)(i) through (iii)
of this section.
(i) For pressure relief devices in off-site material service
subject to Sec. 63.691(c) of this subpart, report the results of all
monitoring conducted within the reporting period.
(ii) For pressure relief devices in off-site material service
subject to Sec. 63.691(c)(2)(i) of this subpart, report any instrument
reading of 500 ppm above background or greater, if detected more than 5
days after the pressure release.
(iii) For pressure relief devices in off-site material service
subject to Sec. 63.691(c)(3) of this subpart, report each pressure
release to the atmosphere, including the following information:
(A) The source, nature, and cause of the pressure release.
(B) The date, time, and duration of the pressure release.
(C) An estimate of the quantity of HAP listed in Table 1 of this
subpart emitted during the pressure release and the method used for
determining this quantity.
(D) The actions taken to prevent this pressure release.
(E) The measures adopted to prevent future such pressure releases.
(6) Pressure tank closure device or bypass deviation report. The
owner or operator must submit to the Administrator the information
specified in paragraph (b)(6)(iv) of this section when any of the
conditions in paragraphs (b)(6)(i) through (iii) of this section are
met.
(i) Any pressure tank closure device, as specified in Sec.
63.685(h)(2) of this subpart, has released to the atmosphere.
(ii) Any closed vent system that includes bypass devices that could
divert a vent a stream away from the control device and into the
atmosphere, as specified in Sec. 63.693(c)(2) of this subpart, has
released directly to the atmosphere.
(iii) Any open-ended valve or line in an emergency shutdown system
which is designed to open automatically in the event of a process
upset, as specified in 40 CFR 63.167(d) or 40 CFR 61.242-6(d), has
released directly to the atmosphere.
(iv) The pressure tank closure device or bypass deviation report
must include the information specified in paragraphs (b)(6)(iv)(A)
through (E) of this section.
(A) The source, nature and cause of the release.
(B) The date, time and duration of the discharge.
(C) An estimate of the quantity of HAP listed in Table 1 of this
subpart emitted during the release and the method used for determining
this quantity.
(D) The actions taken to prevent this release.
(E) The measures adopted to prevent future such releases.
* * * * *
0
17. Section 63.698 is amended by revising paragraph (c) introductory
text and adding paragraph (c)(5) to read as follows:
Sec. 63.698 Implementation and enforcement.
* * * * *
(c) The authorities that cannot be delegated to State, local, or
Tribal agencies are as specified in paragraphs (c)(1) through (5) of
this section.
* * * * *
(5) Approval of alternatives to the electronic reporting
requirements in Sec. 63.697(a)(3).
0
18. Table 2 to subpart DD of part 63 is amended by:
[[Page 37893]]
0
a. Removing entries 63.1(a)(13) and 63.1(a)(14);
0
b. Revising entries 63.1(b)(2), 63.1(c)(3), and 63.1(c)(4);
0
c. Removing entry 63.4(a)(1) through 63.4(a)(3) and adding entries
63.4(a)(1)-63.4(a)(2) and 63.4(a)(3);
0
d. Revising entries 63.4(a)(5) and 63.5(a)(1);
0
e. Revising entries 63.5(b)(5), 63.6(b)(3), 63.6(b)(4);
0
f. Removing entry 63.6(e) and adding entries 63.6(e)(1)(i) through
63.6(e)(1)(iii), 63.6(e)(2), and 63.6(e)(3);
0
g. Revising entry 63.6(f)(1);
0
h. Adding entry 63.7(a)(4);
0
i. Revising entries 63.7(e)(1) and 63.7(f);
0
j. Revising entry 63.8(c)(1)(iii);
0
k. Revising entry 63.9(g);
0
l. Revising entries 63.10(b)(2)(i) through (v);
0
m. Removing entry 63.10(c) and adding entries 63.10(c)(1)-(6),
63.10(c)(7)-(8), and 63.10(c)(9)-(15);
0
n. Removing entries 63.10(d)(5)(i) and 63.10(d)(5)(ii), and adding
entry 63.10(d)(5);
0
o. Removing entry 63.10(e) and adding entries 63.10(e)(1)-63.10(e)(2),
63.10(e)(3), and 63.10(e)(4); and
0
p. Adding entry 63.16 to read as follows:
Table 2 to Subpart DD of Part 63--Applicability of Paragraphs in Subpart A of This Part 63--General Provisions
to Subpart DD
----------------------------------------------------------------------------------------------------------------
Subpart A reference Applies to Subpart DD Explanation
----------------------------------------------------------------------------------------------------------------
* * * * * * *
63.1(b)(2).................................... No........................... Reserved.
* * * * * * *
63.1(c)(3).................................... No........................... Reserved.
63.1(c)(4).................................... No........................... Reserved.
* * * * * * *
63.4(a)(1)-63.4(a)(2)......................... Yes..........................
63.4(a)(3).................................... No........................... Reserved.
* * * * * * *
63.4(a)(5).................................... No........................... Reserved.
* * * * * * *
63.5(a)(1).................................... Yes..........................
* * * * * * *
63.5(b)(5).................................... No........................... Reserved.
* * * * * * *
63.6(b)(3).................................... No...........................
63.6(b)(4).................................... No...........................
* * * * * * *
63.6(e)(1)(i)................................. No........................... See Sec. 63.683(e) of this
subpart for general duty
requirement.
63.6(e)(1)(ii)................................ No........................... .................................
63.6(e)(1)(iii)............................... Yes.......................... .................................
63.6(e)(2).................................... No........................... Reserved.
63.6(e)(3).................................... No...........................
63.6(f)(1).................................... No...........................
* * * * * * *
63.7(a)(4).................................... Yes..........................
* * * * * * *
63.7(e)(1).................................... No........................... See Sec. 63.694(l) of this
subpart.
* * * * * * *
63.7(f)....................................... Yes..........................
* * * * * * *
63.8(c)(1)(iii)............................... No...........................
* * * * * * *
63.9(g)....................................... Yes..........................
* * * * * * *
63.10(b)(2)(i)................................ No...........................
63.10(b)(2)(ii)............................... No........................... See Sec. 63.696(h) of this
subpart for recordkeeping of (1)
date, time and duration; (2)
listing of affected source or
equipment, and an estimate of
the volume of each regulated
pollutant emitted over the
standard; and (3) actions to
minimize emissions and correct
the failure.
63.10(b)(2)(iii).............................. Yes..........................
63.10(b)(2)(iv)............................... No...........................
63.10(b)(2)(v)................................ No...........................
[[Page 37894]]
* * * * * * *
63.10(c)(1)-(6)............................... No...........................
63.10(c)(7)-(8)............................... Yes..........................
63.10(9)-(15)................................. No...........................
* * * * * * *
63.10(d)(5)................................... No........................... See Sec. 63.697(b)(3) of this
subpart for reporting of
malfunctions.
63.10(e)(1)-63.10(e)(2)....................... No...........................
63.10(e)(3)................................... Yes..........................
63.10(e)(4)................................... No...........................
* * * * * * *
63.16......................................... No...........................
----------------------------------------------------------------------------------------------------------------
* * * * *
0
19. Table 3 to subpart DD of part 63 is revised to read as follows:
Table 3 to Subpart DD of Part 63--Tank Control Levels for Tanks at
Existing Affected Sources as Required by 40 CFR 63.685(b)(1)(i)
------------------------------------------------------------------------
Maximum HAP vapor
pressure of off-
Tank design capacity (cubic site material Tank control level
meters) managed in tank
(kilopascals)
------------------------------------------------------------------------
Design capacity less than 75 Maximum HAP vapor Level 1.
m\3\. pressure less
than 76.6 kPa.
Design capacity less than 75 Maximum HAP vapor Level 2, except that
m\3\. pressure equal fixed roof tanks
to or greater equipped with an
than 76.6 kPa. internal floating
roof and tanks
equipped with an
external floating
roof as provided for
in Sec.
63.685(d)(1) and (2)
of this subpart
shall not be used.
Design capacity equal to or Maximum HAP vapor Level 1.
greater than 75 m\3\ and less pressure less
than 151 m\3\. than 27.6 kPa.
Maximum HAP vapor Level 2.
pressure equal
to or greater
than 27.6 kPa.
Design capacity equal to or Maximum HAP vapor Level 1.
greater than 151 m\3\. pressure less
than 5.2 kPa.
Maximum HAP vapor Level 2.
pressure equal
to or greater
than 5.2 kPa.
------------------------------------------------------------------------
0
20. Table 4 to subpart DD of part 63 is revised to read as follows:
Table 4 to Subpart DD of Part 63--Tank Control Levels for Tanks at
Existing Affected Sources as Required by 40 CFR 63.685(b)(1)(ii)
------------------------------------------------------------------------
Maximum HAP vapor
pressure of off-
Tank design capacity (cubic site material Tank control level
meters) managed in tank
(kilopascals)
------------------------------------------------------------------------
Design capacity less than 75 Maximum HAP vapor Level 1.
m\3\. pressure less
than 76.6 kPa.
Design capacity less than 75 Maximum HAP vapor Level 2, except that
m\3\. pressure equal fixed roof tanks
to or greater equipped with an
than 76.6 kPa. internal floating
roof and tanks
equipped with an
external floating
roof as provided for
in Sec.
63.685(d)(1) and (2)
of this subpart
shall not be used.
Design capacity equal to or Maximum HAP vapor Level 1.
greater than 75 m\3\ and less pressure less
than 151 m\3\. than 13.1 kPa.
Maximum HAP vapor Level 2.
pressure equal
to or greater
than 13.1 kPa.
Design capacity equal to or Maximum HAP vapor Level 1.
greater than 151 m\3\. pressure less
than 5.2 kPa.
Maximum HAP vapor Level 2.
pressure equal
to or greater
than 5.2 kPa.
------------------------------------------------------------------------
[[Page 37895]]
0
21. Table 5 is added to subpart DD of part 63 to read as follows:
Table 5 to Subpart DD of Part 63--Tank Control Levels for Tanks at New
Affected Sources as Required by 40 CFR 63.685(b)(2)
------------------------------------------------------------------------
Maximum HAP vapor
pressure of off-
Tank design capacity (cubic site material Tank control level
meters) managed in tank
(kilopascals)
------------------------------------------------------------------------
Design capacity less than 38 Maximum HAP vapor Level 1.
m\3\. pressure less
than 76.6 kPa.
Design capacity less than 38 Maximum HAP vapor Level 2, except that
m\3\. pressure equal fixed roof tanks
to or greater equipped with an
than 76.6 kPa. internal floating
roof and tanks
equipped with an
external floating
roof as provided for
in Sec.
63.685(d)(1) and (2)
of this subpart
shall not be used.
Design capacity equal to or Maximum HAP vapor Level 1.
greater than 38 m\3\ and less pressure less
than 151 m\3\. than 13.1 kPa.
Maximum HAP vapor Level 2.
pressure equal
to or greater
than 13.1 kPa.
Design capacity equal to or Maximum HAP vapor Level 1.
greater than 151 m\3\. pressure less
than 0.7 kPa.
Maximum HAP vapor Level 2.
pressure equal
to or greater
than 0.7 kPa.
------------------------------------------------------------------------
[FR Doc. 2014-13490 Filed 7-1-14; 8:45 am]
BILLING CODE 6560-50-P