[Federal Register Volume 88, Number 81 (Thursday, April 27, 2023)]
[Proposed Rules]
[Pages 25574-25590]
[FR Doc No: 2023-07627]

=======================================================================
-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 63

[EPA-HQ-OAR-2022-0787; FRL-9846-01-OAR]
RIN 2060-AV80

National Emission Standards for Hazardous Air Pollutants:
Ethylene Production, Miscellaneous Organic Chemical Manufacturing,
Organic Liquids Distribution (Non-Gasoline), and Petroleum Refineries
Reconsideration

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule; reconsideration of final rule.

-----------------------------------------------------------------------

SUMMARY: On July 6, 2020, the U.S. Environmental Protection Agency
(EPA) finalized the residual risk and technology review (RTR) conducted
for the Ethylene Production source category, which is part of the
Generic Maximum Achievable Control Technology (GMACT) Standards
National Emission Standards for Hazardous Air Pollutants (NESHAP); on
July 7, 2020, the EPA finalized the RTR conducted for the Organic
Liquids Distribution (Non-Gasoline) NESHAP; and on August 12, 2020, the
EPA finalized the RTR conducted for the Miscellaneous Organic Chemical
Manufacturing NESHAP. Amendments to the Petroleum Refineries NESHAP
were most recently finalized on February 4, 2020. Subsequently, the EPA
received and granted various petitions for reconsideration on these
NESHAP for, among other things, the provisions related to the work
practice standards for pressure relief devices (PRDs), emergency
flaring, and degassing of floating roof storage vessels. In response to
the petitions, the EPA is proposing amendments to the work practice
standards for PRDs, emergency flaring, and degassing of floating roof
storage vessels. In addition, the EPA is proposing other technical
corrections and clarifications for each of the rules. The EPA will not
respond to comments addressing any other issues or any other provisions
of the final rule not specifically addressed in this proposed
rulemaking.

DATES:
    Comments. Comments must be received on or before June 12, 2023.
Under the Paperwork Reduction Act (PRA), comments on the information
collection provisions are best assured of consideration if the Office
of Management and Budget (OMB)

receives a copy of your comments on or before May 30, 2023.
    Public hearing. If anyone contacts us requesting a public hearing
on or before May 2, 2023, we will hold a virtual public hearing. See
SUPPLEMENTARY INFORMATION for information on requesting and registering
for a public hearing.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-HQ-
OAR-2022-0787, by any of the following methods:
    Federal eRulemaking Portal: https://www.regulations.gov/ (our
preferred method). Follow the online instructions for submitting
comments.
    Email: [email protected]. Include Docket ID No. EPA-HQ-OAR-
2022-0787 in the subject line of the message.
    Fax:<PHONE_NUMBER>. Attention Docket ID No. EPA-HQ-OAR-2022-0787.
    Mail: U.S. Environmental Protection Agency, EPA Docket Center,
Docket ID No. EPA-HQ-OAR-2022-0787, Mail Code 28221T, 1200 Pennsylvania
Avenue NW, Washington, DC 20460.
    Hand/Courier Delivery: EPA Docket Center, WJC West Building, Room
3334, 1301 Constitution Avenue NW, Washington, DC 20004. The Docket
Center's hours of operation are 8:30 a.m.-4:30 p.m., Monday-Friday
(except Federal holidays).
    Instructions: All submissions received must include the Docket ID
No. for this rulemaking. Comments received may be posted without change
to https://www.regulations.gov/, including any personal information
provided. For detailed instructions on sending comments and additional
information on the rulemaking process, see the SUPPLEMENTARY
INFORMATION section of this document. Out of an abundance of caution
for members of the public and our staff, the EPA Docket Center and
Reading Room are open to the public by appointment only. Our Docket
Center staff also continues to provide remote customer service via
email, phone, and webform. Hand deliveries and couriers may be received
by scheduled appointment only. For further information on EPA Docket
Center services and the current status, please visit us online at
https://www.epa.gov/dockets.

FOR FURTHER INFORMATION CONTACT: For questions about this proposed
action, contact Ms. Angie Carey, Sector Policies and Programs Division
(E143-01), Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711; telephone number:<PHONE_NUMBER>; fax number:<PHONE_NUMBER>;
and email address: [email protected].

SUPPLEMENTARY INFORMATION:
    Participation in virtual public hearing. To request a virtual
hearing, contact the public hearing team at<PHONE_NUMBER> or by email
at [email protected]. If requested, the hearing will be held
via virtual platform on May 12, 2023. The hearing will convene at 10
a.m., Eastern Time (ET) and conclude at 5 p.m. ET. The EPA may close a
session 15 minutes after the last pre-registered speaker has testified
if there are not additional speakers. The EPA will announce further
details on the virtual public hearing website at https://www.epa.gov/stationary-sources-air-pollution/petroleum-refinery-sector-rule-risk-and-technology-review-and-new.
    If a public hearing is requested, the EPA will begin pre-
registering speakers for the hearing no later than 1 business day after
a request has been received. To register to speak at the virtual
hearing, please use the online registration form available at https://www.epa.gov/stationary-sources-air-pollution/petroleum-refinery-sector-rule-risk-and-technology-review-and-new or contact the public hearing
team at<PHONE_NUMBER> or by email at [email protected]. The
last day to pre-register to speak at the hearing will be May 9, 2023.
Prior to the hearing, the EPA will post a general agenda that will list
pre-registered speakers in approximate order at https://www.epa.gov/stationary-sources-air-pollution/petroleum-refinery-sector-rule-risk-and-technology-review-and-new.
    The EPA will make every effort to follow the schedule as closely as
possible on the day of the hearing; however, please plan for the
hearing to run either ahead of schedule or behind schedule.
    Each commenter will have 4 minutes to provide oral testimony. The
EPA encourages commenters to submit a copy of their oral testimony as
written comments to the rulemaking docket.
    The EPA may ask clarifying questions during the oral presentations
but will not respond to the presentations at that time. Written
statements and supporting information submitted during the comment
period will be considered with the same weight as oral testimony and
supporting information presented at the public hearing.
    Please note that any updates made to any aspect of the hearing will
be posted online at https://www.epa.gov/stationary-sources-air-pollution/petroleum-refinery-sector-rule-risk-and-technology-review-and-new. While the EPA expects the hearing to go forward as set forth
above, please monitor our website or contact the public hearing team at
(888) 372-8699 or by email at [email protected] to determine if
there are any updates. The EPA does not intend to publish a document in
the Federal Register announcing updates.
    If you require the services of a translator or a special
accommodation such as audio description, please pre-register for the
hearing with the public hearing team and describe your needs by May 4,
2023. The EPA may not be able to arrange accommodations without advance
notice.
    Docket. The EPA has established a docket for this rulemaking under
Docket ID No. EPA-HQ-OAR-2022-0787. All documents in the docket are
listed in https://www.regulations.gov/. Although listed, some
information is not publicly available, e.g., Confidential Business
Information (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. With the exception of such material, publicly available docket
materials are available electronically in https://www.regulations.gov/
or in hard copy at the EPA Docket Center, Room 3334, WJC West Building,
1301 Constitution Avenue 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.
    Instructions. Direct your comments to Docket ID No. EPA-HQ-OAR-
2022-0787. 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 https://www.regulations.gov/, including any personal
information provided, unless the comment includes information claimed
to be CBI or other information whose disclosure is restricted by
statute. Do not submit electronically to https://www.regulations.gov/
any information that you consider to be CBI or other information whose
disclosure is restricted by statue. This type of information should be
submitted as discussed below.
    The EPA may publish any comment received to its public docket.
Multimedia submissions (audio, video, etc.) must be accompanied by a
written comment. The written comment is considered the official comment
and

should include discussion of all points you wish to make. The EPA will
generally not consider comments or comment contents located outside of
the primary submission (i.e., on the Web, cloud, or other file sharing
system). For additional submission methods, the full EPA public comment
policy, information about CBI or multimedia submissions, and general
guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.
    The https://www.regulations.gov/ website allows you to submit your
comment anonymously, 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
https://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
digital storage media 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
should be free of any defects or viruses. For additional information
about the EPA's public docket, visit the EPA Docket Center homepage at
https://www.epa.gov/dockets.
    Submitting CBI. Do not submit information containing CBI to the EPA
through https://www.regulations.gov/. Clearly mark the part or all of
the information that you claim to be CBI. For CBI information on any
digital storage media that you mail to the EPA, note the docket ID,
mark the outside of the digital storage media as CBI, and identify
electronically within the digital storage media 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 directly to the public docket through the procedures
outlined in Instructions above. If you submit any digital storage media
that does not contain CBI, mark the outside of the digital storage
media clearly that it does not contain CBI and note the docket ID.
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.
    Our preferred method to receive CBI is for it to be transmitted
electronically using email attachments, File Transfer Protocol (FTP),
or other online file sharing services (e.g., Dropbox, OneDrive, Google
Drive). Electronic submissions must be transmitted directly to the
Office of Air Quality Planning and Standards (OAQPS) CBI Office at the
email address [email protected] and, as described above, should include
clear CBI markings and note the docket ID. If assistance is needed with
submitting large electronic files that exceed the file size limit for
email attachments, and if you do not have your own file sharing
service, please email [email protected] to request a file transfer link.
If sending CBI information through the postal service, please send it
to the following address: 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-2022-0787. The
mailed CBI material should be double wrapped and clearly marked. Any
CBI markings should not show through the outer envelope.
    Preamble acronyms and abbreviations. Throughout this document the
use of ``we,'' ``us,'' or ``our'' is intended to refer to the EPA. 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: {* * * WILL NEED TO REVIEW LIST LATER IN THE PROCESS, DELETE
UNUSED ACRONYMS, ADD OTHER COMMONLY USED ACRONYMS{time}

atm-m3/mol atmospheres per mole per cubic meter
ACC American Chemistry Council
AFPM American Fuels and Petrochemicals Manufacturers
AMEL alternative means of emissions limitation
API American Petroleum Institute
CAA Clean Air Act
CBI Confidential Business Information
CDX Central Data Exchange
CEDRI Compliance and Emissions Data Reporting Interface
CEMS continuous emission monitoring systems
CFR Code of Federal Regulations
EMACT Ethylene Production MACT
EPA Environmental Protection Agency
ET Eastern Time
GMACT Generic Maximum Achievable Control Technology
HAP hazardous air pollutant(s)
LEL lower explosive limit
MACT maximum achievable control technology
MCPU miscellaneous organic chemical manufacturing process unit
MON Miscellaneous Organic Chemical Manufacturing NESHAP
NESHAP national emission standards for hazardous air pollutants
NOCS notification of compliance status
NTTAA National Technology Transfer and Advancement Act
OLD Organic Liquids Distribution (Non-Gasoline)
OMB Office of Management and Budget
ppm parts per million
ppmw parts per million by weight
PRA Paperwork Reduction Act
PRD pressure relief device
RFA Regulatory Flexibility Act
RTR risk and technology review
SSM startup, shutdown, and malfunction
TCEQ Texas Commission on Environmental Quality
UMRA Unfunded Mandates Reform Act
U.S. United States

    Organization of this document. The information in this preamble is
organized as follows:

I. General Information
    A. What is the source of authority for the reconsideration
action?
    B. Does this action apply to me?
    C. Where can I get a copy of this document and other related
information?
II. Background
    A. Ethylene Production
    B. Organic Liquids Distribution (Non-Gasoline)
    C. Miscellaneous Organic Chemical Manufacturing
    D. Petroleum Refineries
III. Reconsideration Issues, Request for Public Comments, and Other
Proposed Changes
    A. Pressure Relief Devices and Emergency Flaring
    B. Storage Vessel Degassing
    C. Other Technical Corrections and Clarifications
    D. What compliance dates are we proposing?
IV. Summary of Cost, Environmental, and Economic Impacts
    A. What are the affected facilities?
    B. What are the air quality impacts?
    C. What are the cost impacts?
    D. What are the economic impacts?
    E. What are the benefits?
    F. What analysis of environmental justice did we conduct?
V. 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 (PRA)
    C. Regulatory Flexibility Act (RFA)
    D. Unfunded Mandates Reform Act (UMRA)
    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 (NTTAA) and
1 CFR Part 51
    J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations

I. General Information

A. What is the source of authority for the reconsideration action?

    The statutory authority for this action is provided by sections 112
and 307(d)(7)(B) of the Clean Air Act (CAA) (42 U.S.C. 7412 and
7607(d)(7)(B)).

B. Does this action apply to me?

    Table 1 of this preamble lists the NESHAP and associated regulated
industrial source categories that are the subject of this proposal.
Table 1 is not intended to be exhaustive, but rather provides 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. Federal, state, local, and tribal
government entities would not be affected by this proposed action. Each
of the source categories covered by this proposal were defined in the
Initial List of Categories of Sources Under Section 112(c)(1) of the
Clean Air Act Amendments of 1990 (see 57 FR 31576; July 16, 1992) and
Documentation for Developing the Initial Source Category List, Final
Report (see EPA-450/3-91-030, July 1992), as well as the National
Emission Standards for Hazardous Air Pollutants; Revision of Initial
List of Categories of Sources and Schedule for Standards Under Sections
112(c) and (e) of the Clean Air Act Amendments of 1990 (61 FR 28197;
June 4, 1996), as presented here.

    Table 1--NESHAP and Industrial Source Categories Affected by This
                             Proposed Action
------------------------------------------------------------------------
       Source category               NESHAP            NAICS \1\ code
------------------------------------------------------------------------
Ethylene Production.........  40 CFR part 63,       325110.
                               subparts XX and YY.
Miscellaneous Organic         40 CFR part 63,       3251, 3252, 3253,
 Chemical Manufacturing.       subpart FFFF.         3254, 3255, 3256,
                                                     and 3259, with
                                                     several exceptions.
Organic Liquids Distribution  40 CFR part 63,       3222, 3241, 3251,
 (Non-Gasoline).               subpart EEEE.         3252, 3259, 3261,
                                                     3361, 3362, 3399,
                                                     4247, 4861, 4869,
                                                     4931, 5622.
Petroleum Refineries........  40 CFR part 63,       324110.
                               subpart CC.
------------------------------------------------------------------------
\1\ North American Industry Classification System.

    The Ethylene Production source category includes any chemical
manufacturing process unit in which ethylene and/or propylene are
produced by separation from petroleum refining process streams or by
subjecting hydrocarbons to high temperatures in the presence of steam.
The ethylene production unit includes the separation of ethylene and/or
propylene from associated streams such as a C4 product,\1\
pyrolysis gasoline, and pyrolysis fuel oil. The ethylene production
unit does not include the manufacture of Synthetic Organic Chemical
Manufacturing Industry (SOCMI) chemicals such as the production of
butadiene from the C4 stream and aromatics from pyrolysis
gasoline.
---------------------------------------------------------------------------

    \1\ The C4 product stream is a hydrocarbon product
stream from an ethylene production unit consisting of compounds with
4 carbon atoms (i.e., butanes, butenes, butadienes).
---------------------------------------------------------------------------

    The Organic Liquids Distribution (Non-Gasoline) source category
includes, but is not limited to, those activities associated with the
storage and distribution of organic liquids other than gasoline, at
sites which serve as distribution points from which organic liquids may
be obtained for further use and processing. The distribution activities
include the storage of organic liquids in storage tanks not subject to
other 40 CFR part 63 standards and transfers into or out of the tanks
from or to cargo tanks, containers, and pipelines.
    After the initial source category listings, in a November 7, 1996,
document (61 FR 57602), the Agency combined 21 of the 174 originally
defined source categories, and other organic chemical processes which
were not included in the original 174 source category list, into one
source category called the ``Miscellaneous Organic Chemical Processes''
source category. In a November 18, 1999, document (64 FR 63035), the
Agency divided the ``Miscellaneous Organic Chemical Processes'' source
category into 2 new source categories called the ``Miscellaneous
Organic Chemical Manufacturing'' source category and the
``Miscellaneous Coating Manufacturing'' source category. The
Miscellaneous Organic Chemical Manufacturing source category includes
any facility engaged in the production of benzyltrimethylammonium
chloride, carbonyl sulfide chelating agents, chlorinated paraffins,
ethylidene norbornene, explosives, hydrazine, photographic chemicals,
phthalate plasticizers, rubber chemicals, symmetrical
tetrachloropyridine, oxybisphenoxarsine/1,3-diisocyanate, alkyd resins,
polyester resins, polyvinyl alcohol, polyvinyl acetate emulsions,
polyvinyl butyral, polymerized vinylidene chloride, polymethyl
methacrylate, maleic anhydride copolymers, or any other organic
chemical processes not covered by another maximum achievable control
technology (MACT) standard. Many of these organic chemical processes
involve similar process equipment, emission points, and control
equipment, and are in many cases collocated with other source
categories.
    The Petroleum Refineries sector includes 2 source categories. The
Petroleum Refineries MACT 1 source category includes any facility
engaged in producing gasoline, naphthas, kerosene, jet fuels,
distillate fuel oils, residual fuel oils, lubricants, or other products
from crude oil or unfinished petroleum derivatives. The refinery
process units in this source category include, but are not limited to,
thermal cracking, vacuum distillation, crude distillation,
hydroheating/hydrorefining, isomerization, polymerization, lubricating
(``lube'') oil processing, and hydrogen production. The Petroleum
Refineries MACT 2--Catalytic Cracking (Fluid and Other) Units,
Catalytic Reforming Units, and Sulfur Recovery Units source category
includes any facility engaged in producing gasoline, naphthas,
kerosene, jet fuels, distillate fuel oils, residual fuel oils,
lubricants, or other products from

crude oil or unfinished petroleum derivates.

C. 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. Following signature by the
EPA Administrator, the EPA will post a copy of this proposed action at
https://www.epa.gov/stationary-sources-air-pollution/petroleum-refinery-sector-rule-risk-and-technology-review-and-new, https://www.epa.gov/stationary-sources-air-pollution/acetal-resins-acrylic-modacrylic-fibers-carbon-black-hydrogen, https://www.epa.gov/stationary-sources-air-pollution/miscellaneous-organic-chemical-manufacturing-national-emission, and https://www.epa.gov/stationary-sources-air-pollution/organic-liquids-distribution-national-emission-standards-hazardous. Following publication in the Federal Register, the
EPA will post the Federal Register version of the proposal and key
technical documents at this same website.
    Redline strikeout versions of each rule showing the edits that
would be necessary to incorporate the changes proposed in this action
are presented in the memoranda titled Proposed Regulatory Text Edits
for Subpart EEEE, Proposed Regulatory Text Edits for Subpart FFFF,
Proposed Regulatory Text Edits for Subpart YY, and Proposed Regulatory
Text Edits for Subpart CC, available in the docket for this action
(Docket ID No. EPA-HQ-OAR-2022-0787).

II. Background

A. Ethylene Production

    The Ethylene Production MACT standards (herein called the EMACT
standards) for the Ethylene Production source category are contained in
the GMACT NESHAP, which also includes MACT standards for several other
source categories. The EMACT standards were promulgated on July 12,
2002 (67 FR 46258), and codified at 40 CFR part 63, subparts XX and YY.
As promulgated in 2002, and further amended on April 13, 2005 (70 FR
19266), and July 6, 2020 (85 FR 40386), the EMACT standards regulate
hazardous air pollutant (HAP) emissions from ethylene production units
located at major sources (as defined by CAA section 112(a)(1)). An
ethylene production unit is a chemical manufacturing process unit in
which ethylene and/or propylene are produced by separation from
petroleum refining process streams or by subjecting hydrocarbons to
high temperatures in the presence of steam. The EMACT standards define
the affected source as all storage vessels, ethylene process vents,
transfer racks, equipment, waste streams, heat exchange systems, and
ethylene cracking furnaces and associated decoking operations that are
associated with each ethylene production unit located at a major source
as defined in CAA section 112(a)(1).
    Following promulgation of the EMACT standards in July 2020, the EPA
received 2 petitions for reconsideration in September 2020. The EPA
received a joint petition from the American Chemistry Council (ACC) and
American Fuel & Petrochemical Manufacturers (AFPM) and a petition from
Earthjustice (on behalf of RISE St. James, Louisiana Bucket Brigade,
Louisiana Environmental Action Network, Texas Environmental Justice
Advocacy Services, Air Alliance Houston, Community In-Power &
Development Association, Clean Air Council, Center for Biological
Diversity, Environmental Integrity Project, and Sierra Club). Copies of
the petitions are provided in the EMACT RTR rulemaking docket (EPA-HQ-
OAR-2017-0357). The ACC/AFPM petitioned the EPA on, among other things,
the storage vessel degassing provisions, ethylene cracking furnace
burner repair provisions, and ethylene cracking furnace isolation valve
inspections. Earthjustice petitioned the EPA on, among other things,
the force majeure and exemption allowances for PRDs and emergency
flaring. The ACC/AFPM and Earthjustice also raised other issues that
are not being addressed in this rulemaking.
    On April 19, 2022, the EPA sent a letter to petitioners informing
them that it would grant reconsideration of the provisions addressing
the work practice standards for PRDs, emergency flaring, and degassing
of floating roof storage vessels. The EPA also stated in the letter to
petitioners that it is continuing to review all issues raised in the
petitions. A copy of the letter to petitioners is available in the
docket for this rulemaking. The EPA will not respond to comments
addressing any other issues or any other provisions of the final rule
not specifically addressed in this proposed rulemaking.

B. Organic Liquids Distribution (Non-Gasoline)

    The Organic Liquids Distribution (Non-Gasoline) (herein called OLD)
NESHAP was promulgated on February 3, 2004 (69 FR 5038) and is codified
at 40 CFR part 63, subpart EEEE. Organic liquids are any crude oils
downstream of the first point of custody transfer and any non-crude oil
liquid that contains at least 5 percent by weight of any combination of
the 98 HAP listed in table 1 of 40 CFR part 63, subpart EEEE. For the
purposes of the OLD NESHAP, as promulgated in 2004, and further amended
on July 28, 2006 (71 FR 42898), April 23, 2008 (73 FR 21825), July 17,
2008 (73 FR 40977), and July 7, 2020 (85 FR 40740), organic liquids do
not include gasoline, kerosene (No. 1 distillate oil), diesel (No. 2
distillate oil), asphalt, heavier distillate oil and fuel oil, fuel
that is consumed or dispensed on the plant site, hazardous waste,
wastewater, ballast water, or any non-crude liquid with an annual
average true vapor pressure less than 0.7 kilopascals (0.1 pounds per
square inch (psi)). Emission sources controlled by the OLD NESHAP are
storage tanks, transfer operations, transport vehicles while being
loaded, and equipment leak components (valves, pumps, and sampling
connections) that have the potential to leak.
    The EPA received three petitions for reconsideration for the OLD
NESHAP in September 2020. The EPA received petitions from the American
Petroleum Institute (API) and AFPM, Stoel Rives LLP (on behalf of
Alyeska Pipeline Company), and Earthjustice (on behalf of California
Communities Against Toxics, Coalition for a Safe Environment, and
Sierra Club). Copies of the petitions are provided in the docket for
this rulemaking. The API/AFPM and Stoel Rives LLP (on behalf of Alyeska
Pipeline Company) commented on storage vessel degassing. The API/AFPM,
Stoel Rives, and Earthjustice also raised other issues that are not
being addressed in this rulemaking.
    On September 8, 2021, the EPA sent a letter to petitioners
informing them that it would grant voluntary reconsideration on certain
issues, including the work practice standards for storage vessel
degassing that apply broadly. Other issues for which EPA stated that it
would grant voluntary reconsideration in the September 8, 2021, letter
(i.e., work practice standards for venting from conservation vents on
the Valdez Marine Terminal's crude oil fixed roof tanks, fenceline
monitoring) are still being reviewed and are not part of this action,
and the EPA will not respond to comments addressing these other issues
in this proposed rulemaking. The EPA also stated in the letter to
petitioners that it is continuing to review all issues raised in the
petitions. A copy of the letter to

petitioners is available in the docket for this rulemaking.

C. Miscellaneous Organic Chemical Manufacturing

    The Miscellaneous Organic Chemical Manufacturing NESHAP (herein
called the MON) for the Miscellaneous Organic Chemical Manufacturing
source category was promulgated on November 10, 2003 (68 FR 63852), and
codified at 40 CFR part 63, subpart FFFF. As promulgated in 2003, and
further amended on July 1, 2005 (70 FR 38562), July 14, 2006 (71 FR
40316), and August 12, 2020 (85 FR 49084), the MON regulates HAP
emissions from miscellaneous organic chemical manufacturing process
units (MCPUs) located at major sources. An MCPU includes a
miscellaneous organic chemical manufacturing process, as defined in 40
CFR 63.2550(i), and must meet the following criteria: it manufactures
any material or family of materials described in 40 CFR 63.2435(b)(1);
it processes, uses, or generates any of the organic HAP described in 40
CFR 63.2435(b)(2); and, except for certain process vents that are part
of a chemical manufacturing process unit, as identified in 40 CFR
63.100(j)(4), the MCPU is not an affected source or part of an affected
source under another subpart of 40 CFR part 63. An MCPU also includes
any assigned storage tanks and transfer racks; equipment in open
systems that is used to convey or store water having the same
concentration and flow characteristics as wastewater; and components
such as pumps, compressors, agitators, PRDs, sampling connection
systems, open-ended valves or lines, valves, connectors, and
instrumentation systems that are used to manufacture any material or
family of materials described in 40 CFR 63.2435(b)(1). Sources of HAP
emissions regulated by the MON include the following: process vents,
storage tanks, transfer racks, equipment leaks, wastewater streams, and
heat exchange systems.
    Following promulgation of the MON in August 2020, the EPA received
five petitions for reconsideration between October and December 2020.
The EPA received petitions from Earthjustice (on behalf of RISE St.
James, Louisiana Bucket Brigade, Louisiana Environmental Action
Network, Texas Environmental Justice Advocacy Services, Air Alliance
Houston, Ohio Valley Environmental Coalition, Blue Ridge Environmental
Defense League, Environmental Justice Health Alliance for Chemical
Policy Reform, Sierra Club, Environmental Integrity Project, and Union
of Concerned Scientists), the Texas Commission on Environmental Quality
(TCEQ), Squire Patton Boggs LLP (on behalf of Huntsman Petrochemical,
LLC), and the ACC (who submitted two petitions). Copies of the
petitions are provided in the docket for this rulemaking. The ACC
petitioned the EPA on, among other things, the storage vessel degassing
provisions and requirements for ethylene oxide sources. Earthjustice
petitioned the EPA on, among other things, the force majeure and
exemption allowances for PRDs and emergency flaring. The TCEQ, ACC, and
Huntsman Petrochemical requested that the EPA reassess the MON risk
assessment for issues around ethylene oxide risks; the EPA is
responding to that reconsideration petition request in a separate
rulemaking (87 FR 77985; December 21, 2022). Earthjustice and ACC also
raised other issues that are not being addressed in this rulemaking.
    On June 17, 2021, the EPA sent a letter to petitioners informing
them that it is continuing to review all issues raised in the
petitions. A copy of the letter to petitioners is available in the
docket for this rulemaking.

D. Petroleum Refineries

    On December 1, 2015 (80 FR 75178), the EPA finalized amendments to
the petroleum refinery sector rules as the result of a sector RTR.
These amendments included, among other provisions, adding work practice
requirements to Petroleum Refinery MACT 1 (40 CFR part 63 subpart CC)
for PRDs and flares in 40 CFR 63.648(j) and 63.670(o), respectively.
These provisions specifically provide requirements for owners and
operators to follow in the event of an atmospheric PRD release or
emergency flaring event, including performing root cause analysis for
each event and implementing corrective action(s) in accordance with the
rule requirements. The atmospheric PRD release and emergency flaring
provisions specify the conditions that result in a violation of the
work practice standards in 40 CFR 63.648(j)(3)(v) and 63.670(o)(7),
respectively. The owner or operator is required to track the number of
events by emission unit and root cause. An atmospheric PRD release or
emergency flaring event for which the root cause is determined to be
poor maintenance or operator error is a violation of the work practice
standards. Two atmospheric PRD releases or two emergency flaring events
from the same emission unit when determined to be the result of the
same root cause in a 3-year period is a violation of the work practice
standard. Finally, three atmospheric PRD releases or 3 emergency
flaring events from the same emission unit regardless of the root cause
is a violation of the work practice standard (also referred to as ``the
`three strikes' provisions''). Notably, if the root cause is determined
to be due to a force majeure event, as defined in 40 CFR 63.641, it
does not count towards the criteria for a violation of the work
practice standards.
    The EPA received three petitions to reconsider the December 2015
final rule. Two petitions were filed on January 19, 2016, and February
1, 2016, jointly by API and the AFPM. In response to the January 19,
2016, petition, the EPA issued a proposal on February 9, 2016 (81 FR
6814), and a final rule on July 13, 2016 (81 FR 45232), fully
responding to the January 19, 2016, petition for reconsideration. The
third petition was filed on February 1, 2016, by Earthjustice on behalf
of Air Alliance Houston, California Communities Against Toxics, Clean
Air Council, Coalition for a Safe Environment, Community In-Power &
Development Association, Del Amo Action Committee, Environmental
Integrity Project, Louisiana Bucket Brigade, Sierra Club, Texas
Environmental Justice Advocacy Services, and Utah Physicians for a
Healthy Environment. The Earthjustice petition claimed that several
aspects of the revisions to the Petroleum Refinery MACT 1 were not
proposed and that, therefore, the public was precluded from commenting
on the altered provisions during the public comment period, including,
among other provisions, the work practice standards for PRDs and
emergency flaring. On June 16, 2016, the EPA sent letters to
petitioners granting reconsideration on issues where petitioners
claimed they had not been provided an opportunity to comment. These
petitions and letters granting reconsideration are available for review
in the rulemaking docket (see Docket ID Item No. EPA-HQ-OAR-2022-0787).
On October 18, 2016 (81 FR 71661), the EPA proposed for public comment
the issues for which reconsideration was granted in the June 16, 2016,
letters. The EPA solicited public comment on five issues in the
proposal, including: the work practice standard for PRDs; the work
practice standard for emergency flaring events; and the assessment of
risk as modified based on implementation of these PRD and emergency
flaring work practice standards. On February 4, 2020, the EPA issued a
final action (85 FR 6064) setting forth its decisions on each of the
five reconsideration items included in the October 18, 2016 (81 FR
71661),

proposed notice of reconsideration (October 2016 proposed notice of
reconsideration).
    On April 6, 2020, Earthjustice submitted a petition for
reconsideration of the February 2020 final action on behalf of Air
Alliance Houston, California Communities Against Toxics, Clean Air
Council, Coalition For A Safe Environment, Community In-Power &
Development Association, Del Amo Action Committee, Environmental
Integrity Project, Louisiana Bucket Brigade, Sierra Club, Texas
Environmental Justice Advocacy Services, and Utah Physicians for a
Healthy Environment (Docket Item No. EPA-HQ-OAR-2010-0682-1000). The
petition for reconsideration requested that the EPA reconsider five
issues in the February 4, 2020, final rule: (1) The EPA's rationale
that the PRD standards and emergency flaring standards are continuous;
(2) the EPA's rationale for the PRD standards under CAA sections
112(d)(2) and 112(d)(3); (3) the EPA's rationale for separate work
practice standards for flares operating above the smokeless capacity;
(4) the EPA's rationale for risk acceptability and risk determination;
and (5) the EPA's analysis and rationale in its assessment of acute
risk. The EPA initially denied the April 6, 2020, petition for
reconsideration (85 FR 67665) and provided detailed responses to each
of the five issues raised in the April 2020 petition in a September 3,
2020, letter, which is available in the Petroleum Refinery rulemaking
docket (Docket Item No. EPA-HQ-OAR-2010-0682-0999). Subsequently, after
further consideration, the EPA wrote a letter on April 19, 2022, to
petitioners explaining that it has decided to undertake reconsideration
on select provisions related to the work practice standards for PRDs
and emergency flaring. Specifically, the EPA is reconsidering the
inclusion of the force majeure allowances in the PRD and emergency
flaring work practice standards as discussed in detail in section III.A
of this preamble. As noted in our April 19, 2022, letter, we may
reconsider additional issues in the future.

III. Reconsideration Issues, Request for Public Comments, and Other
Proposed Changes

    To address selected issues for which we granted reconsideration and
to provide other technical corrections, the EPA is proposing revisions
to the EMACT standards, OLD NESHAP, MON, and Petroleum Refineries
NESHAP. The EPA is proposing revisions to the work practice standards
for PRDs and emergency flaring related to force majeure provisions in
the EMACT standards, MON, and Petroleum Refineries NESHAP, and is
proposing standards for the degassing of storage vessels in the EMACT
standards, OLD NESHAP, and MON. The EPA is also proposing to add
requirements for pressure-assisted flares and mass spectrometers to the
Petroleum Refineries NESHAP to align this rule with other more recent
chemical sector rules and eliminate the need to request site-specific
alternative means of emission limitations (AMELs) for these units. In
addition, the EPA is proposing other technical corrections,
clarifications, and correction of typographical errors in all rules. To
ensure public participation in its final decisions, the EPA is
requesting public comment on these specific issues as described below.
The EPA will not respond to comments addressing any other issues or any
other provisions of the final rule not specifically addressed in this
proposed rulemaking.

A. Pressure Relief Devices and Emergency Flaring

    As described in the background section II.D of this preamble, the
work practice standards for PRDs and emergency flaring in Petroleum
Refinery MACT 1 provide the criteria for violating the work practice
standards based on a count of the events by emission unit and root
cause. The count of events by emission unit currently excludes events
for which the root cause is determined to be force majeure as defined
in 40 CFR 63.641. In their April 2020 petition, petitioners took issue
with the inclusion of the force majeure allowance as they claim that it
makes the standards non-continuous and that it is inappropriate to
include this allowance based on the inclusion of similar provisions in
two local California rules (South Coast Air Quality Management
District; Bay Area Air Quality Management District). The EPA fully
responded to these issues in the September 2020 letter (Docket Item No.
EPA-HQ-OAR-2010-0682-0999) and the EPA's position on these issues has
not changed. Namely, there are components of both the PRD management
provisions and emergency flaring provisions that apply at all times and
not all components of the standard must apply at all times for the
standard to be continuous. The EPA also stated that its consideration
of the continuous nature of the work practice standards and their basis
in the two local California rules has been set forth in a manner
consistent with public review and comment requirements.
    However, during our recent reconsideration efforts, the EPA
recognizes that despite the term ``force majeure'' being carefully
defined, the force majeure allowance in the work practice standards may
present difficulties for determining compliance. It may also represent
a provision that some facility owners or operators may seek to use to
avoid incurring violations and pursuing potentially disruptive
corrective actions. The reporting requirements for the work practice
standards in 40 CFR 63.655(g)(10)(iv) and 63.655(g)(11)(iv) provide
that the refinery owner or operator must report the results of the root
cause and corrective action analysis completed during the reporting
period (i.e., semiannually). The reporting of the event-specific data
associated with the work practice standards is currently included in
periodic reports that are submitted to the delegated state authority
and/or EPA Regional Office, as applicable, and are thus not publicly
available. During the root cause analysis and corrective action
process, refineries maintain discretion when categorizing and reporting
the root cause of atmospheric PRD releases and emergency flaring
events, thereby placing the onus on the EPA to determine whether the
definition of force majeure has been appropriately applied.
    In acknowledgement of these concerns and to fully inform our
decision as to whether rule amendments for Petroleum Refinery MACT 1
are necessary with respect to the force majeure allowance, we reviewed
periodic reports from refineries in Texas and Louisiana obtained
through the EPA Regional Office. For atmospheric PRD releases, we
reviewed periodic reports from 18 refineries spanning 0.5-1.5 years of
time per refinery, and a total of 12.5 refinery-years. These reports
covered semiannual compliance reporting periods during calendar years
2019 through 2021. During that time, there were atmospheric PRD
releases at four of these 18 refineries. There were five total
releases. None of the determined root causes were attributed to events
that meet the definition of the term force majeure. For emergency
flaring events, we reviewed periodic reports from 22 refineries
spanning 0.5-1.5 years of time per refinery, and a total of 15.5
refinery-years. During that time, there were emergency flaring events
at six of these 22 refineries. There were eight total events at these
six refineries. Of these, three of the eight events were attributed to
causes that, as reported, meet the definition of the term force

majeure. In reviewing these data, we conclude that atmospheric PRD
releases and emergency flaring events are relatively infrequent at
refineries and that those determined to have a root cause characterized
as a force majeure event are even less so.
    When we initially proposed the Petroleum Refinery MACT 1
requirements, the primary data available for event releases were from
the TCEQ Air Emission Event Report Database,\2\ which requires the
reporting of emission events that exceed a reportable quantity and
industry comments with limited supporting documentation. Based on the
available data, we concluded that the ``three strikes'' provisions were
reasonable, but there were concerns that circumstances outside of the
refinery's control may cause violations. Based on the data available
now, we conclude that the frequency of these types of releases is lower
than originally expected. This lower frequency may be due to the
refinery sector rule's provisions, like the redundant prevention
measures for PRD, which were implemented in the final rule and that
apply at all times. Given these data and the lower frequency of force
majeure events, we conclude that the force majeure allowances included
in the provisions for PRDs and flares are not necessary. We also find
that by removing the force majeure allowance, the rule is strengthened,
and compliance becomes easier to assess as it is determined purely
based on the count of events by emission unit and root cause. There is
no categorization or interpretation related to the root cause of the
event. The corrective action component of the work practice standards
would now apply to all events regardless of the root cause and all
events would count towards the violation criteria set forth in the
standard. As noted, our analyses were performed on data we requested
directly from the EPA Regional Offices, which are not readily available
to the public. We find that making these data readily available to the
public would increase the transparency of the events regulated by the
work practice standards.
---------------------------------------------------------------------------

    \2\ TCEQ Search Air Emission Event Reports, https://www.texas.gov/.
---------------------------------------------------------------------------

    Therefore, in this proposed action, the EPA is proposing to remove
the term force majeure from the list of defined terms in 40 CFR 63.641
as well as to remove the force majeure allowance from the criteria for
a violation of the work practice standards for atmospheric PRD releases
and emergency flaring events in 40 CFR 63.648(j)(3) and 63.670(o)(7).
We are also proposing to amend the reporting requirements for the
event-specific work practice standard data in 40 CFR 63.655(g)(10)(iv)
and 63.655(g)(11)(iv) to require these data to be reported
electronically through the EPA's Central Data Exchange (CDX) using the
Compliance and Emissions Data Reporting Interface (CEDRI).
    The EMACT standards and MON include the same work practice
standards for PRDs and emergency flaring as Petroleum Refinery MACT 1.
The OLD NESHAP also includes the same work practice standard for
emergency flaring as Petroleum Refinery MACT 1. Because compliance with
the work practice standards for existing sources begins in summer of
2023 for these 3 rules, we do not have the number of events that count
towards violations for these NESHAP, but the rationale and benefits for
removing the force majeure allowance follows exactly as discussed above
for refineries. These include removing the onus from the EPA as to
whether the definition of force majeure has been appropriately applied
when determining the root cause, making compliance easier to assess,
and strengthening both rules. For flares, the EMACT standards, OLD
NESHAP, and MON directly reference the petroleum refinery flare
provisions at 40 CFR 63.670. Therefore, the above-mentioned proposed
revisions to 40 CFR 63.670(o)(7) for emergency flaring events would be
automatically incorporated into the requirements for the EMACT
standards, OLD NESHAP, and MON. In addition, the EPA is proposing to
remove the term ``force majeure'' from the list of defined terms in 40
CFR 63.2406, because this definition was included specifically due to
the force majeure provisions for emergency flaring events. The EPA is
also proposing to remove the term ``force majeure'' from the list of
defined terms in 40 CFR 63.1103(e)(2) and 63.2550 as well as to remove
the force majeure allowance from the criteria for a violation of the
work practice standard for atmospheric PRD releases in 40 CFR
63.1107(h)(3) and 63.2480(e)(3). Lastly, the EPA is proposing new
reporting requirements for the EMACT standards at 40 CFR
63.1110(a)(10)(iii) to require electronic reporting, through the CDX
using CEDRI, of the event-specific work practice standard data in 40
CFR 63.1110(e)(4)(iv) and 63.1110(e)(8)(iii). We note that the MON
already has a more general compliance report template for electronic
reporting, see 40 CFR 63.2520(e), which will automatically incorporate
electronic reporting of the event-specific work practice standard data.

B. Storage Vessel Degassing

    The 2020 EMACT standards, OLD NESHAP, and MON included a standard
for storage vessel degassing to control emissions from shutdown
operations (see the work practice standards in 40 CFR 63.1103(e)(10),
63.2346(a)(6), and 63.2470(f), respectively). The rules allow storage
vessels to be vented to the atmosphere once a storage vessel degassing
concentration threshold is met (i.e., less than 10 percent of the lower
explosive limit (LEL)) and all standing liquid has been removed from
the vessel to the extent practicable. The requirements are applicable
to fixed roof and floating roof storage vessels that are subject to
control requirements in each of the rules. We did not propose a storage
vessel degassing standard in the EMACT standards, OLD NESHAP, and MON,
but we finalized a standard based on comments received for all 3 rules.
We based the degassing standard on Texas permit conditions, which
represented the MACT floor.\3\ Specifically, permit condition 6
(applicable to floating roof storage vessels) and permit condition 7
(applicable to fixed roof storage vessels) formed the basis of the
storage vessel degassing standard.
---------------------------------------------------------------------------

    \3\ Texas Permit Conditions are available at: https://www.tceq.texas.gov/assets/public/permitting/air/Guidance/NewSourceReview/mss/chem-mssdraftconditions.pdf.
---------------------------------------------------------------------------

    The petitioners argued that including a storage vessel degassing
standard for floating roof storage vessels was not a logical outgrowth
of the proposal and that it was not possible to comment on this
standard. As previously noted in section II of this preamble, the EPA
granted reconsideration on this issue. The petitioners stated that
while they did identify the Texas permit conditions as a reference in
their comments, certain key information was not incorporated into the
final EMACT standards, OLD NESHAP, and MON for the degassing of
floating roof storage vessels. Additionally, the petitioners argued
that they did not request additional work practices for floating roof
storage vessels for which owners and operators already elect to comply
with the floating roof storage vessels requirements in 40 CFR part 63,
subpart WW because, even with the removal of the shutdown exemption,
the petitioners contended that it is still possible to comply with the
subpart WW provisions (because these provisions already provide
continuous control during degassing by limiting the vapor space of the
storage vessel via the

floating roof and requiring prompt and continuous filling until the
roof is refloated).
    We disagree with the petitioners' claims that a separate standard
for floating roof storage vessel degassing is not needed due to the
removal of the shutdown exemption. Rather, as discussed here, the EPA
must set a storage vessel degassing standard that applies to all
storage vessels under CAA section 112, and 40 CFR part 63, subpart WW,
does not adequately control degassing emissions from floating roof
storage vessels. First, the emission source for which the EPA is
required to set a MACT standard is storage vessels, regardless of
whether the source has a fixed roof or floating roof. While petitioners
contend that their comments did not specifically mention the degassing
of floating roof storage vessels (rather, only the degassing of fixed
roof storage vessels), the CAA is clear that the EPA is required to set
MACT standards for each emission source, which, in this instance,
includes all storage vessels, regardless of roof type. Further, the EPA
has never subcategorized storage vessels by roof type. Rather, the
EMACT standards, OLD NESHAP, and MON allow owners or operators to
choose from different options to control emissions from storage vessels
and comply with the MACT standards. As is relevant, using a floating
roof that meets the requirements in 40 CFR part 63, subpart WW, is one
of the control options owners or operators may choose for control of
emissions during normal storage vessel operations. Thus, the EPA is
required under CAA section 112 to set a MACT standard for previously
unregulated degassing operations for all storage vessels (regardless of
roof type) and not for some subset of storage vessels as the
petitioners assert.
    Second, storage vessel degassing is a unique shutdown activity with
operations and emissions that are completely different from normal
storage vessel operations. While the previous MACT standards-controlled
emissions of breathing losses and working losses from normal storage
vessel operations, storage vessel degassing is a very infrequent event
(i.e., occurring on average every 14 years based on EMACT data) for
which commenters requested an alternative standard in the EMACT
standards, OLD NESHAP, and MON when EPA removed the shutdown exemption
in those NESHAP. The storage vessel degassing process first requires
owners or operators to empty the tank of liquid contents. When this
occurs, the floating roof on a floating roof storage vessel no longer
acts as a control for HAP emissions as it is no longer floating on the
liquid in the tank and minimizing vapor space. Rather, the roof is
landed on legs and effectively acts as a fixed roof storage vessel with
respect to emissions generation. From there, the storage vessel is
generally purged, typically with an inert material such as nitrogen or
steam, for a period of time to remove residual vapors before the vessel
can be opened to perform maintenance. This purge stream generates HAP
emissions and is the subject of the MACT control requirements for which
the EPA is proposing alternative standards. As such, complying with the
40 CFR part 63, subpart WW, requirements for floating roof storage
vessels is not an effective control for HAP emissions during the
degassing phase of a floating roof storage vessel, when it essentially
operates as a fixed roof storage vessel. Furthermore, storage vessel
degassing provisions in Texas and the South Coast Air Quality
Management District in California exist precisely because a standard
specific to storage vessel degassing is warranted, including for
floating roof storage vessels.
    After determining that a standard is necessary for degassing of all
storage vessels (regardless of roof type), the EPA reviewed the Texas
permit conditions again to determine if revisions to the degassing
standard for floating roof storage vessels in the EMACT standards, OLD
NESHAP, and MON are appropriate. As noted by the petitioners, Texas
permit condition 6.B does provide certain allowances for the degassing
process for floating roof storage vessels; a 24-hour window is provided
to start controlled degassing after the floating roof storage vessel
has been drained, and the storage vessel may be opened during this
period only to set up for degassing and cleaning. We determined that
the 24-hour window stipulates how long a floating roof storage vessel
can be landed before it needs to be filled again or degassed, but it
does not have a direct bearing on the underlying control standard for
degassing operations. As such, we are not revising the rules to
incorporate the 24-hour window into the storage vessel degassing
standard. Regarding the opening of the floating roof storage vessel to
set up for degassing and cleaning, while we do not believe the current
language precludes a facility from taking this step, we are revising
the standard to include related language for clarity. For example, the
petitioners noted that it is necessary to make connections to a
temporary control device to control the floating roof storage vessel
degassing emissions, which may require opening the storage vessel to
make these connections. Therefore, we are proposing that a floating
roof storage vessel may be opened prior to degassing to set up
equipment (i.e., make connections to a temporary control device), but
this must be done in a limited manner and must not actively purge the
storage vessel while connections are made.
    An opportunity to comment on the storage vessel degassing
provisions was not previously provided because the provisions were
included in the final rules but not in the proposed rules. Therefore,
the EPA is re-proposing what was finalized for each rule in 2020 and is
proposing additional revisions to address degassing of floating roof
storage vessels. We are proposing storage vessel degassing standards
for the EMACT standards at 40 CFR 63.1103(e)(10), the OLD NESHAP at 40
CFR 63.2346(a)(6), and the MON at 40 CFR 63.2470(f).

C. Other Technical Corrections and Clarifications

    There are several additional revisions that we are proposing for
the EMACT standards, OLD NESHAP, MON, and Petroleum Refineries NESHAP
to address other technical corrections and clarifications and to
correct typographical errors. These proposed corrections and
clarifications are summarized in table 2 through table 4 of this
preamble in the following sections. We request public comment on each
of these revisions.
1. EMACT Standards
    Table 2 of this preamble provides responses to specific issues
raised by stakeholders and presents proposed revisions to the EMACT
standards to address certain technical corrections, clarifications, and
typographical errors.

  Table 2--Summary of Proposed Revisions to 40 CFR Part 63, Subpart YY
------------------------------------------------------------------------
          Provision               Issue summary       Proposed revision
------------------------------------------------------------------------
40 CFR 63.1103(e)(7)(i).....  Delay of burner       An opportunity to
                               repair provisions:    comment on the
                              A petitioner argued    delay of burner
                               that requiring an     repair provisions
                               ethylene cracking     was not previously
                               furnace to            provided because
                               implement the delay   the provisions were
                               of burner repair      included in the
                               provisions            final rule but not
                               finalized in the      in the proposed
                               2020 final rule is    rule. Therefore,
                               impracticable and     the EPA is re-
                               is inconsistent       proposing what was
                               with what the best    finalized along
                               performers are        with the following
                               doing. The            revisions for delay
                               petitioner stated     of burner repair.
                               that a significant    The EPA is
                               amount of             proposing to remove
                               preparation is        the requirement
                               needed to shut down   that the owner or
                               an ethylene           operator may only
                               cracking furnace      delay burner repair
                               and that no source    beyond 1 calendar
                               can comply with the   day if a shutdown
                               delay of burner       for repair would
                               repair provisions     cause greater
                               as written.           emissions than the
                               Accordingly, where    potential emissions
                               a burner cannot be    from delaying
                               repaired without an   repair. We agree
                               ethylene cracking     that this
                               furnace shutdown,     requirement is
                               owners or operators   impracticable and
                               would have to         could lead to more
                               decoke their          decoking events and
                               ethylene cracking     more emissions from
                               furnaces              decoking of
                               immediately (i.e.,    ethylene cracking
                               within 1 day of       furnaces. Instead,
                               identifying flame     the EPA is
                               impingement),         proposing that
                               leading to more       delay of repair
                               decoking events and   beyond 1 calendar
                               subsequently more     day is allowed if
                               emissions from the    the repair cannot
                               decoking of           be completed during
                               ethylene cracking     normal operations,
                               furnaces.             the burner cannot
                                                     be shut down
                                                     without
                                                     significantly
                                                     impacting the
                                                     furnace heat
                                                     distribution and
                                                     firing rate, and
                                                     action is taken to
                                                     reduce flame
                                                     impingement as much
                                                     as possible during
                                                     continued
                                                     operation. We are
                                                     also maintaining
                                                     that if a delay of
                                                     repair is required
                                                     to fully resolve
                                                     burner flame
                                                     impingement, repair
                                                     must be completed
                                                     following the next
                                                     planned decoking
                                                     operation (and
                                                     before returning
                                                     the ethylene
                                                     cracking furnace
                                                     back to normal
                                                     operations) or
                                                     during the next
                                                     ethylene cracking
                                                     furnace complete
                                                     shutdown (when the
                                                     ethylene cracking
                                                     furnace firebox is
                                                     taken completely
                                                     offline), whichever
                                                     is earlier.
40 CFR 63.1103(e)(8)(i).....  Isolation valve       The EPA agrees with
                               inspection and        the petitioner and
                               repair:               is proposing
                              A petitioner           language to allow
                               requested that the    facilities to wait
                               EPA revise the        and rectify
                               requirement to        isolation valve
                               rectify poor          issues after a
                               isolation prior to    decoking operation,
                               continuing decoking   provided that the
                               operations. The       owner or operator
                               petitioner argued     can reasonably
                               that certain          demonstrate that
                               isolation valve       damage to the
                               repairs must be       radiant tube(s) or
                               completed after the   ethylene cracking
                               ethylene cracking     furnace would occur
                               furnace is shut       if the repair was
                               down, which           attempted prior to
                               consequently          completing a
                               requires the          decoking operation
                               ethylene cracking     and/or prior to the
                               furnace to go         ethylene cracking
                               through decoking.     furnace being shut
                               The petitioner said   down.
                               that if a furnace
                               is not decoked
                               prior to shutdown,
                               damage can occur to
                               the furnace tubes
                               and could pose a
                               safety issue. In
                               addition, the
                               petitioner noted
                               that some isolation
                               valves serve gas
                               streams from
                               multiple ethylene
                               cracking furnaces,
                               and there may be
                               instances when all
                               furnaces would need
                               to be decoked and
                               shut down to
                               properly rectify
                               the isolation valve
                               issue. The
                               petitioner argued
                               that allowing for
                               some flexibility is
                               necessary for
                               facilities to
                               operate properly
                               and to avoid
                               damaging equipment.
40 CFR 63.1110(e)(4)(iii)...  Provision contains a  The EPA is proposing
                               typographical error.  to replace ``Sec.
                                                     63.1109(e)(7)''
                                                     with ``Sec.
                                                     63.1109(e)(6)'' to
                                                     correct the
                                                     typographical
                                                     error.
40 CFR 63.1102(c)(11),        Provisions contain a  The EPA is proposing
 (d)(2)(ii), and (e)(2)(iii).  typographical error.  to replace ``Sec.
                                                     63.1108(a)(4)(i)''
                                                     with ``Sec.
                                                     63.1108(a)(4)'' to
                                                     correct a
                                                     typographical error
                                                     that we made while
                                                     removing startup,
                                                     shutdown, and
                                                     malfunction (SSM)
                                                     exemptions. Our
                                                     intent was to
                                                     include all of 40
                                                     CFR 63.1108(a)(4)
                                                     in the EMACT
                                                     standards. This
                                                     proposed revision
                                                     would also resolve
                                                     analogous
                                                     typographical
                                                     errors for the
                                                     carbon black and
                                                     cyanide chemicals
                                                     source categories
                                                     that are also
                                                     contained in 40 CFR
                                                     part 63, subpart
                                                     YY.

40 CFR 63.1103(e)(4)(iii)     Provisions needing    The EPA is proposing
 and 63.1110(a)(10)(i),        technical             to remove
 (ii), (iii), and (iv).        clarifications or     duplication and
                               removal.              point directly to
                                                     40 CFR 63.9(k) when
                                                     the source is
                                                     required to submit
                                                     certain reports to
                                                     CEDRI.
                                                     Specifically,
                                                     instructions for
                                                     submitting reports
                                                     electronically
                                                     through CEDRI,
                                                     including
                                                     instructions for
                                                     submitting CBI and
                                                     asserting a claim
                                                     of EPA system
                                                     outage or force
                                                     majeure, were
                                                     recently added to
                                                     40 CFR 63.9(k) (85
                                                     FR 73885);
                                                     therefore, text
                                                     related to these
                                                     requirements is no
                                                     longer necessary in
                                                     the EMACT
                                                     standards.
------------------------------------------------------------------------

2. OLD NESHAP
    Table 3 of this preamble provides responses to specific issues
raised by stakeholders and presents proposed revisions to the OLD
NESHAP to address certain technical corrections, clarifications, and
typographical errors.

 Table 3--Summary of Proposed Revisions to 40 CFR Part 63, Subpart EEEE
------------------------------------------------------------------------
           Provision              Issue summary      Proposed revision
------------------------------------------------------------------------
40 CFR 63.2346(a)(6)..........  Provision          The EPA is proposing
                                 contains a         to replace ``items 3
                                 typographical      through 6 of table 2
                                 error.             to this subpart''
                                                    with ``items 2
                                                    through 6 of table 2
                                                    to this subpart'' to
                                                    correct the
                                                    typographical error.
40 CFR 63.2346(e).............  Provision          The EPA is proposing
                                 contains a         to replace ``storage
                                 typographical      vessels'' with
                                 error.             ``storage tanks'' to
                                                    correct the
                                                    typographical error.
40 CFR 63.2378(e)(3)..........  Provisions         The EPA is proposing
                                 needing            to add the word
                                 technical          ``planned'' in front
                                 clarifications.    of ``routine
                                                    maintenance'' in the
                                                    last sentence of the
                                                    provision to further
                                                    clarify that the
                                                    exemption only
                                                    applies to periods
                                                    of planned routine
                                                    maintenance. We are
                                                    also proposing to
                                                    replace ``storage
                                                    vessel'' with
                                                    ``storage tank'' in
                                                    the last sentence of
                                                    the provision to
                                                    correct a
                                                    typographical error.
40 CFR 63.2378(e)(4)..........  Provisions         To create consistency
                                 needing            in the time period
                                 technical          during which the
                                 clarifications.    bypass provision
                                                    applies (i.e., the
                                                    level of material in
                                                    the storage tank
                                                    must not be
                                                    increased during the
                                                    same time period
                                                    that breathing loss
                                                    emissions bypass the
                                                    fuel gas system or
                                                    process), we are
                                                    proposing to delete
                                                    ``to perform routine
                                                    maintenance'' from
                                                    the last sentence of
                                                    40 CFR
                                                    63.2378(e)(4). We
                                                    are also proposing
                                                    to replace ``storage
                                                    vessel'' with
                                                    ``storage tank'' in
                                                    the last sentence of
                                                    the provision to
                                                    correct a
                                                    typographical error.
40 CFR 63.2382(d)(3), and       Provisions         The EPA is proposing
 63.2386(f), (g), (h), (i),      needing            to remove
 and (j).                        technical          duplication and
                                 clarifications     point directly to 40
                                 or removal.        CFR 63.9(k) when the
                                                    source is required
                                                    to submit certain
                                                    reports to CEDRI.
                                                    Specifically,
                                                    instructions for
                                                    submitting reports
                                                    electronically
                                                    through CEDRI,
                                                    including
                                                    instructions for
                                                    submitting CBI and
                                                    asserting a claim of
                                                    EPA system outage or
                                                    force majeure, were
                                                    recently added to 40
                                                    CFR 63.9(k) (85 FR
                                                    73885); therefore,
                                                    text related to
                                                    these requirements
                                                    is no longer
                                                    necessary in the OLD
                                                    NESHAP.
------------------------------------------------------------------------

3. MON
    This section of this preamble presents revisions we are proposing
to the MON heat exchange system requirements. In addition, table 4 of
this preamble provides responses to other specific issues raised by
stakeholders and presents proposed revisions to the MON to address
certain technical corrections, clarifications, and typographical
errors.
    In May 2021, EPA Region 4 received a request from Eastman Chemical
Company to perform alternative monitoring instead of the Modified El
Paso Method to monitor for leaks in Eastman's Tennessee Operations heat
exchange systems, which primarily have cooling water containing soluble
HAP with a high boiling point. Eastman requested that the previous
water sampling requirements for heat exchange system leaks provided in
the MON, which ultimately references 40 CFR 63.104(b) (i.e., use of any
EPA-approved method listed in part 136 of this chapter as long as the
method is sensitive to concentrations as low as 10 parts per million
(ppm) and the same method is used for both entrance and exit samples),
be allowed for cooling water containing certain soluble HAP in lieu of
using the Modified El Paso Method.
    Eastman specifically identified two HAP, 1,4-dioxane and methanol,
which do not readily strip out of water using the Modified El Paso
Method. Eastman's application for alternative monitoring included
experimental data showing that the Modified El Paso Method would likely
not identify a leak of these HAP in heat exchange system cooling water.
Eastman conducted Modified El Paso Method monitoring under controlled
scenarios to determine how much methanol and 1,4-dioxane would be
detected. The scenarios included solutions of water and either methanol
or 1,4-dioxane at concentrations of 1 part per million by weight
(ppmw), 20 ppmw, and 100 ppmw (as measured using water sampling methods
allowed previously in the MON). The Modified El Paso Method did not
detect any

methanol or 1,4-dioxane from the 1 ppmw and 20 ppmw solutions (i.e.,
methanol and 1,4-dioxane did not strip out of the water in detectable
amounts). The Modified El Paso Method detected very little HAP from the
100 ppmw solutions, with a maximum of only 0.17 percent of the 1,4-
dioxane stripping out and being detected.
    Based on this information, the EPA is proposing at 40 CFR
63.2490(e) that the leak monitoring requirements for heat exchange
systems at 40 CFR 63.104(b) may be used in limited instances, instead
of using the Modified El Paso Method to monitor for leaks. We still
maintain that the Modified El Paso Method is the preferred method to
monitor for leaks in heat exchange systems and are proposing that the
requirements of 40 CFR 63.104(b) may only be used if 99 percent by
weight or more of all the organic compounds that could potentially leak
into the cooling water have a Henry's Law Constant less than 5.0E-6
atmospheres per mole per cubic meter (atm-m\3\/mol) at 25[deg] Celsius.
We selected this threshold based on a review of Henry's Law Constants
for the HAP listed in table 4 to subpart F of 40 CFR part 63, as well
as the water-soluble organic compounds listed in Eastman's request.
Henry's Law Constants are available from the EPA at https://comptox.epa.gov/dashboard/. Examples of HAP that have a Henry's Law
Constant of less than 5.0E-6 atm-m\3\/mol at 25[deg] Celsius are
aniline, 2-chloroacetophenone, diethylene glycol diethyl ether,
diethylene glycol dimethyl ether, dimethyl sulfate, 2,4-dinitrotoluene,
1,4-dioxane, ethylene glycol monoethyl ether acetate, ethylene glycol
monomethyl ether acetate, methanol, and toluidine. Many of these HAP
also have very high boiling points, with most above 300 [deg]F, which
means they will generally stay in the cooling water and not be emitted
to the atmosphere. While we are proposing that the leak monitoring and
leak definition requirements at 40 CFR 63.104(b) may be used in limited
instances, we are not proposing that other provisions of 40 CFR 63.104
apply. Instead, for example, facilities that use water sampling to
detect leaks must still comply with the recordkeeping and reporting
requirements of 40 CFR 63.2520(e)(16) and 40 CFR 63.2525(r). We are
proposing revisions at 40 CFR 63.2520(e)(16) and 40 CFR 63.2525(r) to
specify this.
    Table 4 of this preamble provides responses to other specific
issues raised by stakeholders and presents proposed revisions to the
MON to address certain technical corrections, clarifications, and
typographical errors.

 Table 4--Summary of Proposed Revisions to 40 CFR Part 63, Subpart FFFF
------------------------------------------------------------------------
          Provision               Issue summary       Proposed revision
------------------------------------------------------------------------
40 CFR 63.2450(e)(6)(i).....  Provision contains a  The EPA is proposing
                               typographical error.  to replace the
                                                     reference to 40 CFR
                                                     63.148(h)(3) with a
                                                     reference to 40 CFR
                                                     63.148(i)(3) to
                                                     correct the
                                                     typographical
                                                     error.
40 CFR 63.2450(e)(7)........  A petitioner          The EPA is proposing
                               requested that the    to clarify that 40
                               EPA clarify whether   CFR 63.2470(c)(3),
                               certain adsorber      40 CFR
                               provisions            63.2520(d)(6) and
                               referenced within     (e)(13), 40 CFR
                               40 CFR 63.983 and     63.2525(o), and the
                               other related         provisions
                               requirements and      referenced within
                               exceptions (i.e.,     40 CFR 63.983 all
                               40 CFR                apply (in addition
                               63.2470(c)(3), 40     to 40 CFR
                               CFR 63.2520(d)(6)     63.2450(e)(4) and
                               and (e)(13), and 40   (e)(6)) if
                               CFR 63.2525(o))       facilities reduce
                               apply to this         organic HAP
                               paragraph. The        emissions by
                               petitioner also       venting emissions
                               pointed out that it   through a closed-
                               is not clear          vent system to an
                               whether a             adsorber(s) that
                               supplement to the     cannot be
                               notification of       regenerated or a
                               compliance status     regenerative
                               (NOCS) report is      adsorber(s) that is
                               needed, and if        regenerated
                               necessary, what       offsite. We are
                               information should    also clarifying in
                               be provided.          40 CFR
                                                     63.2450(e)(1) that
                                                     40 CFR
                                                     63.2450(e)(1) does
                                                     not apply when
                                                     complying with 40
                                                     CFR 63.2450(e)(7).
                                                    As part of this
                                                     clarification, we
                                                     are also proposing
                                                     a new requirement
                                                     at 40 CFR
                                                     63.2520(d)(6) for
                                                     adsorbers subject
                                                     to the requirements
                                                     of 40 CFR
                                                     63.2450(e)(7)
                                                     requiring a
                                                     supplement to the
                                                     NOCS report within
                                                     150 days after the
                                                     first applicable
                                                     compliance date. We
                                                     are proposing that
                                                     the supplement to
                                                     the NOCS report
                                                     must describe
                                                     whether the
                                                     adsorber cannot be
                                                     regenerated or is a
                                                     regenerative
                                                     adsorber(s) that is
                                                     regenerated offsite
                                                     and must specify
                                                     the breakthrough
                                                     limit and adsorber
                                                     bed life that was
                                                     established during
                                                     the initial
                                                     performance test or
                                                     design evaluation
                                                     of the adsorber.
                                                     Finally, we are
                                                     proposing to revise
                                                     the introductory
                                                     paragraph of 40 CFR
                                                     63.2520 as well as
                                                     the requirement in
                                                     40 CFR 63.2515(d)
                                                     to update the
                                                     reference to the
                                                     proposed 40 CFR
                                                     63.2520(d)(6)
                                                     paragraph.
40 CFR 63.2460(c)(9)........  Provision contains a  The EPA is proposing
                               typographical error.  to replace the
                                                     phrase ``in
                                                     paragraphs
                                                     (c)(9)(i) through
                                                     (vi) of this
                                                     section'' with ``in
                                                     paragraphs
                                                     (c)(9)(i) through
                                                     (iv) of this
                                                     section'' to
                                                     correct the
                                                     typographical
                                                     error.
40 CFR 63.2480(a)...........  Provision contains a  The EPA is proposing
                               typographical error.  to replace the
                                                     phrase ``For each
                                                     light liquid pump,
                                                     valve, and
                                                     connector in
                                                     ethylene oxide
                                                     service'' with
                                                     ``For each light
                                                     liquid pump,
                                                     pressure relief
                                                     device, and
                                                     connector in
                                                     ethylene oxide
                                                     service'' to
                                                     correct the
                                                     typographical
                                                     error.

40 CFR 63.2480(e)(2)(ii) and  A petitioner pointed  It was our intent to
 (e)(2)(iii).                  out that EPA agreed   delete the second
                               in its response to    sentence from these
                               comment document      provisions (i.e.,
                               (see docket item      the requirement to
                               EPA-HQ-OAR-2018-074   conduct monitoring
                               6-0200) to delete     if rupture disks
                               the second sentence   are replaced). As
                               from these            stated in our
                               provisions;           response to comment
                               however, the final    document (see
                               rule (85 FR 49084)    docket item EPA-HQ-
                               does not reflect      OAR-2018-0746-0200)
                               these deletions.      , we agree that the
                                                     language diverges
                                                     from what 40 CFR
                                                     part 63, subpart
                                                     UU, required for
                                                     PRDs. Therefore, we
                                                     are proposing to
                                                     correct this error
                                                     by deleting the
                                                     second sentence
                                                     from these
                                                     provisions.
40 CFR 63.2480(f)(18)(iii)..  Provision contains a  The EPA is proposing
                               typographical error.  to replace ``Sec.
                                                     63.181(b)(2)(i)''
                                                     with ``Sec.
                                                     63.181(b)(3)(i)''
                                                     to correct the
                                                     typographical
                                                     error.
40 CFR 63.2480(f)(18)(vi)...  A petitioner          We agree with the
                               contended that the    petitioner and are
                               reference to          proposing to
                               information           clarify this
                               required to be        provision by
                               reported under 40     including ``in Sec.
                               CFR                     63.165(a).'' The
                               63.182(d)(2)(xiv)     proposed language
                               is too broad and      reads ``The
                               should be more        information in Sec.
                               narrowly described      63.165(a)
                               as ``information in   required to be
                               Sec.   63.165(a)      reported under 40
                               required to be        CFR
                               reported under 40     63.182(d)(2)(xiv)
                               CFR                   is now required to
                               63.182(d)(2)(xiv)''   be reported under
                               in order to clarify   Sec.
                               that the reporting    63.2520(e)(15)(i)
                               requirement is        through (iii).''
                               specific to the
                               recently
                               promulgated PRD
                               requirements.
40 CFR 63.2480(f)(18)(x)....  Provision contains a  The EPA is proposing
                               typographical error.  to replace ``Sec.
                                                     63.1022(a)(1)(v)''
                                                     with ``Sec.
                                                     63.1023(a)(1)(v)''
                                                     to correct the
                                                     typographical
                                                     error.
40 CFR 63.2480(f)(18)(xiii).  A petitioner          We agree with the
                               contended that the    petitioner and are
                               reference to          proposing to
                               information           clarify this
                               required to be        provision by
                               reported under 40     including ``in Sec.
                               CFR 63.1039(b)(4)       63.1030(b).'' The
                               is too broad and      proposed language
                               should be more        reads ``The
                               narrowly described    information in Sec.
                               as ``information in     63.1030(b)
                               Sec.   63.1030(b)     required to be
                               required to be        reported under 40
                               reported under 40     CFR 63.1039(b)(4)
                               CFR 63.1039(b)(4)''   is now required to
                               in order to clarify   be reported under
                               that the reporting    Sec.
                               requirement is        63.2520(e)(15)(i)
                               specific to the       and (ii).''
                               recently
                               promulgated PRD
                               requirements.
40 CFR 63.2493(a)(2)(vi) and  A petitioner          Scrubbers that use
 (b)(4).                       requested             an acid solution
                               clarification of      and reactant tank
                               scrubber monitoring   are the primary
                               parameters and the    focus of the
                               types of scrubbers    scrubber monitoring
                               that are applicable   requirements
                               to certain            because this type
                               requirements. The     of scrubber liquid
                               petitioner stated     is necessary to
                               that the rule is      specifically
                               only applicable to    control ethylene
                               scrubbers that use    oxide. As such, we
                               an acid solution      are not revising
                               and reactant tank,    the monitoring
                               but that other        parameters to apply
                               types of scrubbers    more broadly, such
                               are used in           as to scrubbers
                               instances when        that use water as
                               ethylene oxide is     the scrubbing
                               present in small      liquid. We are
                               amounts. The          proposing
                               petitioner            clarifying language
                               requested that the    that the monitoring
                               pH monitoring         requirements are
                               parameter be          applicable to
                               revised to account    scrubbers ``with a
                               for other types of    reactant tank.'' We
                               scrubbers. The        agree with the
                               petitioner also       petitioner
                               requested that the    regarding
                               temperature of the    temperature
                               ``scrubber liquid''   monitoring and are
                               be monitored          proposing a
                               instead of the        correction that the
                               temperature of the    temperature of the
                               ``water.''            ``scrubber liquid''
                                                     must be monitored.
                                                     If a facility uses
                                                     a scrubber without
                                                     a reactant tank
                                                     that provides
                                                     incidental control
                                                     of ethylene oxide,
                                                     the facility may
                                                     establish site-
                                                     specific parameters
                                                     using 40 CFR
                                                     63.2493(a)(2)(viii)
                                                     and (b)(6).
40 CFR 63.2492(b)...........  A petitioner          We agree with the
                               requested that an     petitioner and are
                               alternative to        proposing to allow
                               sampling and          calculations to be
                               analysis of storage   performed to show
                               tank materials        that the ethylene
                               should be allowed,    oxide concentration
                               to determine if a     is less than 0.1
                               storage tank is in    percent by weight
                               ethylene oxide        of the material
                               service. The          stored in the
                               petitioner stated     storage tank,
                               that information      provided the
                               already exists for    calculations rely
                               some storage tanks    on information
                               to show that the      specific to the
                               ethylene oxide        material stored.
                               concentration in      This may include
                               the material stored   using, for example,
                               is less than 0.1      specific
                               percent by weight     concentration
                               (sometimes            information from
                               significantly so)     safety data sheets.
                               and the requirement
                               to conduct sampling
                               and analysis is
                               unnecessary.
40 CFR 63.2493(b)(2)........  A petitioner          We agree with the
                               requested that the    petitioner that 40
                               EPA include           CFR 63.2493(b)(2)
                               introductory          only applies if the
                               language to clarify   facility chooses to
                               that the              route emissions to
                               requirements apply    a non-flare control
                               only if the           device and chooses
                               facility chooses to   to comply with the
                               route emissions to    1 ppmv standard via
                               a non-flare control   CEMS. Therefore, we
                               device and chooses    are proposing to
                               to comply with the    add introductory
                               1 ppmv standard via   text at 40 CFR
                               continuous emission   63.2493(b)(2) that
                               monitoring systems    clarifies this.
                               (CEMS).
40 CFR 63.2493(d)(3)........  A petitioner          We agree with the
                               contended that the    petitioner to
                               reference to          revise the
                               ``affected source''   provision for
                               should be revised     consistency with
                               to ``MCPU'' to be     table 6 to subpart
                               consistent with the   FFFF of part 63;
                               second column of      therefore, we are
                               table 6 to subpart    proposing to
                               FFFF of part 63.      replace ``affected
                                                     source'' with
                                                     ``MCPU.''
40 CFR 63.2493(d)(4)(v).....  Provision contains a  The EPA is proposing
                               typographical error.  to replace ``Sec.
                                                     63.2445(h)'' with
                                                     ``Sec.
                                                     63.2445(i)'' to
                                                     correct the
                                                     typographical
                                                     error.

40 CFR 63.2493(e)...........  A petitioner          We confirm that
                               requested the EPA     ``delay of repair''
                               clarify whether       provisions do not
                               ``delay of repair''   apply for equipment
                               provisions apply to   in ethylene oxide
                               equipment in          service. However,
                               ethylene oxide        we recognize the
                               service. The          rule language did
                               petitioner noted      not correctly
                               that in the           reflect this. As
                               response to           such, we are
                               comments for the      proposing to revise
                               final rule the EPA    40 CFR 63.2493(e)
                               stated that ``delay   to appropriately
                               of repair''           specify that the
                               provisions do not     ``delay of repair''
                               apply. However, the   provisions of 40
                               petitioner further    CFR part 63,
                               noted, the final      subparts H and UU,
                               rule language did     and 40 CFR part 65,
                               not reflect this.     subpart F, do not
                                                     apply.
40 CFR 63.2520(d)...........  A petitioner pointed  We acknowledge there
                               out that the EPA      was an
                               indicated in the      inconsistency in
                               preamble to the       what we said in the
                               final rule (85 FR     preamble about
                               49084) that           electronic
                               electronic            reporting NOCS
                               reporting is          reports versus what
                               required at 40 CFR    we required in the
                               63.2520(d) for the    final rule.
                               NOCS report;          However, the
                               however, the final    inconsistency is
                               rule does not         irrelevant because
                               contain this          in this rulemaking,
                               requirement. The      we are proposing at
                               petitioner            40 CFR 63.2520(d)
                               requested that the    to require that
                               EPA clarify that      NOCS reports be
                               this was a            submitted
                               misstatement in the   electronically
                               preamble language     through the EPA's
                               and that the NOCS     CEDRI. The proposed
                               report is not         requirement to
                               required to be        submit NOCS reports
                               submitted             electronically will
                               electronically.       increase the ease
                                                     and efficiency of
                                                     data submittal and
                                                     data accessibility.
                                                     For a more thorough
                                                     discussion of
                                                     electronic
                                                     reporting, see the
                                                     memorandum,
                                                     Electronic
                                                     Reporting
                                                     Requirements for
                                                     New Source
                                                     Performance
                                                     Standards (NSPS)
                                                     and National
                                                     Emission Standards
                                                     for Hazardous Air
                                                     Pollutants (NESHAP)
                                                     Rules, which is
                                                     available in the
                                                     docket for this
                                                     rulemaking (see
                                                     Docket Item No. EPA-
                                                     HQ-OAR-2018-0746-01
                                                     69).
40 CFR 63.2525(o)...........  A petitioner          In the final rule
                               requested that the    (85 FR 49084), we
                               EPA update the        inadvertently did
                               recordkeeping         not revise the
                               requirements for      recordkeeping
                               adsorbers that        requirements to
                               cannot be             reflect the
                               regenerated and for   associated
                               regenerative          monitoring
                               adsorbers that are    requirements in 40
                               regenerated offsite   CFR 63.2450(e)(7)
                               to reflect the        (for adsorbers that
                               monitoring            cannot be
                               requirements in the   regenerated and for
                               final rule (85 FR     regenerative
                               49084).               adsorbers that are
                               Specifically, the     regenerated
                               petitioner            offsite). We are
                               requested that the    proposing to
                               EPA revise 40 CFR     correct this by
                               63.2525(o)(1) to      revising 40 CFR
                               require that you      63.2525(o)(1) and
                               must keep records     (2) and removing
                               of the breakthrough   the requirement at
                               limit and bed life    40 CFR
                               for each adsorber     63.2525(o)(4) in
                               established           its entirety, as
                               according to 40 CFR   recommended by the
                               63.2450(e)(7)(i);     petitioner.
                               revise 40 CFR         However, we are not
                               63.2525(o)(2) to      proposing to revise
                               require that you      40 CFR
                               keep records of       63.2525(o)(3) as
                               each outlet HAP or    requested by the
                               TOC concentration     petitioner. We are
                               measured according    keeping the
                               to 40 CFR             language of 40 CFR
                               63.2450(e)(7)(ii)     63.2525(o)(3) ``as
                               and (e)(7)(iii);      is,'' which aligns
                               and revise 40 CFR     with the language
                               2525(o)(3) to         used in 40 CFR
                               require records of    63.2450(e)(7)(iii)(
                               the date and time     B).
                               each adsorber is
                               replaced. The
                               petitioner also
                               requested that EPA
                               remove the
                               requirement at 40
                               CFR 63.2525(o)(4)
                               in its entirety.
40 CFR 63.2520(e)(2)........  Provision contains a  The EPA is proposing
                               typographical error.  to correct the
                                                     spelling of
                                                     ``paragraph.''
40 CFR 63.2450(e)(5)(iv),     Provisions needing    The EPA is proposing
 63.2520(e), (f), (g), (h),    technical             to remove
 and (i).                      clarifications or     duplication and
                               removal.              point directly to
                                                     40 CFR 63.9(k) when
                                                     the source is
                                                     required to submit
                                                     certain reports to
                                                     CEDRI.
                                                     Specifically,
                                                     instructions for
                                                     submitting reports
                                                     electronically
                                                     through CEDRI,
                                                     including
                                                     instructions for
                                                     submitting CBI and
                                                     asserting a claim
                                                     of EPA system
                                                     outage or force
                                                     majeure, were
                                                     recently added to
                                                     40 CFR 63.9(k) (85
                                                     FR 73885);
                                                     therefore, text
                                                     related to these
                                                     requirements is no
                                                     longer necessary in
                                                     the MON.
------------------------------------------------------------------------

4. Petroleum Refineries NESHAP
    In addition to removing the force majeure allowance from the PRD
and emergency flaring work practice standards as discussed in section
III.A of this preamble, we are also proposing other amendments to
Petroleum Refinery MACT 1 that are consistent with flaring provisions
in other recent rules (i.e., EMACT standards) that adopted the
Petroleum Refinery MACT 1 flare requirements but addressed additional
issues, such as adding provisions for pressure-assisted flares. The
proposed amendments include adding pressure-assisted flares to the
definition of the term ``flare'' in 40 CFR 63.641 and adding
appropriate requirements for pressure-assisted flares in 40 CFR 63.670.
These amendments are consistent with the EPA's intention that all types
of flares, including pressure-assisted flares, are covered by the
provisions in Petroleum Refinery MACT 1. The proposed amendments for
pressure-assisted flares include pilot flame standards and requirements
for cross-lighting in 40 CFR 63.670(b), pressure monitoring in 40 CFR
63.670(d)(3), higher combustion zone operating limits in 40 CFR
63.670(e), and requirements to use only the direct calculation methods
for determining the flare vent gas net heating value according to 40
CFR 63.670(l)(5)(ii). We are also proposing reporting and recordkeeping
requirements specific to pressure-assisted flares in 40 CFR

63.655(g)(11)(iii) and (i)(9)(vi), respectively.
    Further, to provide additional flexibility to the monitoring
requirements for flare gas composition as required by 40 CFR 63.670(j),
we are proposing to add mass spectrometry as a method in 40 CFR 63.671.
The current provisions in 40 CFR 63.671 could be interpreted to suggest
that gas chromatographs must be used for flare gas compositional
analysis. This was not our intent. We recognize that there are some
methods, like mass spectrometry, which can determine flare gas
composition without the use of a gas chromatograph. We are proposing to
add specific requirements for calibration and operation of mass
spectrometers that parallel the requirements for gas chromatographs.

D. What compliance dates are we proposing?

    We are not proposing new compliance dates for any revisions that we
are proposing for the EMACT standards, OLD NESHAP, and MON. The rules
that were promulgated in 2020 have still not come into full effect and
owners and operators have until July 6, 2023, to comply with the EMACT
standards, July 7, 2023, for the OLD NESHAP, and August 12, 2023, for
the MON. As such, owners and operators would have until those dates to
comply with the proposed revisions. In addition, the proposed revisions
do not impose substantial new requirements but rather provide clarity
to the rules for owners and operators.
    For most actions that we are proposing for the petroleum refineries
NESHAP, we are positing that facilities would need some time to
successfully apply these revisions, including time to: read and
understand the amended rule requirements; evaluate their operations to
ensure that they can meet the standards during periods of startup and
shutdown, as defined in the rule; and make any necessary adjustments,
including making adjustments to standard operating procedures, and
convert reporting mechanisms to install necessary hardware and
software. The EPA recognizes the confusion that multiple compliance
dates for individual requirements would create and the additional
burden such an assortment of dates would impose. From our assessment of
the timeframe needed for compliance with the revised requirements, the
EPA considers a period of 60 days after the effective date of the final
rule to be the most expeditious compliance period practicable.
Therefore, we are proposing that affected sources must be in compliance
with most of the proposed revisions to the petroleum refineries NESHAP
upon initial startup or within 60 days of the effective date of the
final rule, whichever is later. There is one exception to this
compliance period, discussed next.
    We are proposing that petroleum refinery owners or operators must
comply with the new operating and monitoring requirements for flares
upon initial startup or by the effective date of the final rule,
whichever is later. We believe that compliance with the flare
requirements immediately upon finalizing the rule is necessary to
ensure that pressure-assisted flares are appropriately operated.

IV. Summary of Cost, Environmental, and Economic Impacts

A. What are the affected facilities?

    In our final RTRs, we estimated the following:
    There are 26 facilities subject to the EMACT standards that are
currently operating and five additional facilities under construction.
A complete list of known facilities in the EMACT standards is available
in appendix A of the memorandum, Review of the RACT/BACT/LAER
Clearinghouse Database for the Ethylene Production Source Category (see
Docket ID No. EPA-HQ-OAR-2017-0357-0008).
    There are 173 OLD NESHAP facilities currently operating and four
additional OLD NESHAP facilities under construction. A complete list of
known OLD NESHAP facilities is available in appendix A of the
memorandum, National Impacts of the 2020 Risk and Technology Review
Final Rule for the Organic Liquids Distribution (Non-Gasoline) Source
Category (see Docket ID No. EPA-HQ-OAR-2018-0746-0069).
    There are 201 MON facilities currently operating. A complete list
of known MON facilities is available in appendix 1 of the memorandum,
Residual Risk Assessment for the Miscellaneous Organic Chemical
Manufacturing Source Category in Support of the 2019 Risk and
Technology Review Proposed Rule (see Docket Item No. EPA-HQ-OAR-2018-
0746-0011).
    Additionally, based on the Energy Information Administration's 2021
Refinery Capacity Report, there are 129 operable petroleum refineries
in the United States (U.S.) and the U.S. territories, all of which are
expected to be major sources of HAP emissions.

B. What are the air quality impacts?

    We did not estimate baseline emissions or emissions reductions for
the proposed revisions. None of the proposed revisions would have a
direct and quantifiable impact on emissions because they are minor
revisions to existing requirements.

C. What are the cost impacts?

    We expect minimal to no cost impacts due to the proposed revisions.
There could be minor costs for affected facilities related to reading
the proposed rule, making minor updates to operating procedures in some
limited cases, and making minor adjustments to reporting systems. A few
proposed revisions provide slightly greater flexibility and could yield
minor cost savings. Any potential costs or cost savings are expected to
be negligible.

D. What are the economic impacts?

    No economic impacts are anticipated due to the proposed revisions
because any potential cost impacts are expected to be very minor.

E. What are the benefits?

    The proposed revisions are not expected to yield air quality
benefits because emissions will not be affected. However, the proposed
revisions should improve clarity, monitoring, compliance, and
implementation of the rules for the affected source categories.

F. What analysis of environmental justice did we conduct?

    The proposed revisions are not expected to impact emissions and
therefore we did not conduct an environmental justice analysis.
However, environmental justice analyses were conducted for the final
2020 rules for the EMACT standards, OLD NESHAP, and MON. Further
information regarding these environmental justice analyses is available
at 85 FR 40415, 85 FR 40757, and 85 FR 49129, respectively.

V. Statutory and Executive Order Reviews

    Additional information about these statutes and Executive Orders
can be found at https://www.epa.gov/laws-regulations/laws-and-executive-orders.

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 and was
therefore not submitted to the OMB for review.

B. Paperwork Reduction Act (PRA)

    This action is not expected to impose any new information