[Federal Register Volume 88, Number 221 (Friday, November 17, 2023)]
[Rules and Regulations]
[Pages 80480-80545]
[FR Doc No: 2023-25269]

Vol. 88

Friday,

No. 221

November 17, 2023

Part IV

Environmental Protection Agency

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40 CFR Part 60

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Adoption and Submittal of State Plans for Designated Facilities:
Implementing Regulations Under Clean Air Act Section 111(d); Final Rule

Federal Register / Vol. 88 , No. 221 / Friday, November 17, 2023 /
Rules and Regulations

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 60

[EPA-HQ-OAR-2021-0527; FRL-8606-01-OAR]
RIN 2060-AV48

Adoption and Submittal of State Plans for Designated Facilities:
Implementing Regulations Under Clean Air Act Section 111(d)

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is finalizing
amendments to the regulations that govern the processes and timelines
for state and Federal plans to implement emission guidelines under
Clean Air Act (CAA) New Source Performance Standards for existing
sources (the ``implementing regulations''). The amendments include
revisions to the timing requirements for state and the EPA actions
related to plans; the addition of mechanisms to improve flexibility and
efficiency in plan processes; and new requirements for demonstration of
timely meaningful engagement with pertinent stakeholders--including,
but not limited to, industry, small businesses, and communities most
affected by and vulnerable to the impacts of the plan. This action
additionally provides a process for states' consideration of `remaining
useful life and other factors' (RULOF) in applying a standard of
performance; amends the definition of standard of performance in the
implementing regulations; and clarifies compliance flexibilities that
states may choose to incorporate into state plans, including trading or
averaging. Finally, this action adds requirements for the electronic
submission of state plans and provides several other clarifications and
minor revisions to the implementing regulations.

DATES: This final rule is effective on December 18, 2023.

ADDRESSES: The EPA has established a docket for this action under
Docket ID No. EPA-HQ-OAR-2021-0527. All documents in the docket are
listed on the https://www.regulations.gov/ website. 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 form. Publicly available docket materials are available
electronically through https://www.regulations.gov/.

FOR FURTHER INFORMATION CONTACT: For questions about this action
contact Dr. Michelle Bergin, Sector Policies and Programs Division
(Mail Code D205-01), Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, 109 T.W. Alexander Drive, P.O. Box
12055, Research Triangle Park, North Carolina 27711; telephone number:
(919) 541-2726; email address: [email protected].

SUPPLEMENTARY INFORMATION: Preamble acronyms and abbreviations. We use
multiple acronyms and terms in this preamble. While this list may not
be exhaustive, to ease the reading of this preamble and for reference
purposes, the EPA defines the following terms and acronyms here:

ACE Affordable Clean Energy Rule
ALA American Lung Association
BSER Best System of Emission Reduction
CAA Clean Air Act
CBI confidential business information
CDX Central Data Exchange
CFR Code of Federal Regulations
EG Emission Guideline
EGU electric generating unit
EJ environmental justice
EPA Environmental Protection Agency
FIP Federal Implementation Plan
ICR Information Collection Request
IoP Increments of Progress
NAAQS National Ambient Air Quality Standards
OAQPS Office of Air Quality Planning and Standards
OMB Office of Management and Budget
PRA Paperwork Reduction Act
PM2.5 fine particulate matter (2.5 microns and less)
RTC Response to Comments document
RFA Regulatory Flexibility Act
RIN Regulatory Information Number
RULOF remaining useful life and other factors
SIP State Implementation Plan
SpeCS State Planning Electronic Collaboration System
TAR Tribal Authority Rule
TAS Treatment as a State
TIP Tribal Implementation Plan
UMRA Unfunded Mandates Reform Act
U.S.C. United States Code

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

I. General Information
    A. Does this action apply to me?
    B. Where can I get a copy of this document and other related
information?
    C. Judicial Review and Administrative Review
II. Background
    A. What is the statutory authority for this action?
    B. What is the background for this action?
    C. What changes did we propose?
    D. What outreach and engagement did the EPA conduct?
III. What actions are we finalizing and what is our rationale for
such decisions?
    A. Revised Implementing Timelines
    B. Federal Plan Authority and Timeline Upon Failure to Submit a
Plan
    C. Outreach and Meaningful Engagement
    D. Regulatory Mechanisms for State Plan Implementation
    E. Remaining Useful Life and Other Factors (RULOF) Provisions
    F. Provision for Electronic Submission of State Plans
    G. Other Proposed Modifications and Clarifications
IV. Summary of Cost, Environmental, and Economic Impacts
V. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review;
Executive Order 13563: Improving Regulation and Regulatory Review;
and Executive Order 14094: Modernizing 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)
    J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations
    K. Congressional Review Act (CRA)

I. General Information

A. Does this action apply to me?

    This action applies for the development and adoption of plans for
implementation of CAA section 111(d) final emission guidelines (EGs)
published in the Federal Register after July 8, 2019. In particular,
this action applies to states in the development and submittal of state
plans and to the EPA in processing state plan submissions and to the
EPA in promulgating Federal plans. After the EPA promulgates a final
EG, each state that has one or more designated facilities must develop,
adopt, and submit to the EPA a state plan under CAA section 111(d). The
term ``designated facility'' means ``any existing facility . . . which
emits a designated pollutant and which would be subject to a standard
of performance for that pollutant if the existing facility were an
affected facility [i.e., a new source].'' See 40 CFR 60.21a(b). If a
state fails to submit a plan or if the EPA determines that a state plan
is not

satisfactory, the EPA has the authority to establish a Federal CAA
section 111(d) plan for designated facilities located in the state.
    Under the Tribal Authority Rule (TAR), eligible tribes may seek
approval to implement a plan under CAA section 111(d) in a manner
similar to a state. See 40 CFR part 49, subpart A. Tribes may, but are
not required to, seek approval for treatment in a manner similar to a
state (treatment as a state; TAS) for purposes of developing a Tribal
Implementation Plan (TIP) implementing an EG. If a tribe obtains
approval and submits a TIP, the EPA will use similar timelines and
criteria and will follow similar procedures as those for state plans.
Tribes that choose to develop plans will have the same flexibilities
available to states in this process. The TAR authorizes tribes to
develop and implement one or more of its own air quality programs, or
portions thereof, under the CAA; however, it does not require tribes to
develop a CAA program. Tribes may implement programs that are most
relevant to their air quality needs. A tribe with an approved TAS under
TAR for CAA 111(d) is not required to resubmit TAS approval to
implement an EG subject to subpart Ba.\1\ If a tribe does not seek and
obtain the authority from the EPA to establish a TIP, the EPA has the
authority to establish a Federal CAA section 111(d) plan for designated
facilities that are located in areas of Indian country. A Federal plan
would apply to all designated facilities located in the areas of Indian
country covered by the Federal plan unless and until the EPA approves a
TIP applicable to those facilities.
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    \1\ See the EPA website, https://www.epa.gov/tribal/tribes-approved-treatment-state-tas, for information on those tribes that
have treatment as a state for specific environmental regulatory
programs, administrative functions, and grant programs.
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B. Where can I get a copy of this document and other related
information?

    In addition to being available in the docket, an electronic copy of
this action is available on the internet. Following signature by the
EPA Administrator, the EPA will post a copy of this final action at
https://www.epa.gov/stationary-sources-air-pollution/adoption-and-submittal-state-plans-designated-facilities-40-cfr. Following
publication in the Federal Register, the EPA will post the Federal
Register version of the final rule, a memorandum showing the rule edits
finalized in this action, and key supporting documents at this same
website.

C. Judicial Review and Administrative Review

    Section 307(b)(1) of the CAA governs judicial review of final
actions by the EPA. This section provides, in part, that petitions for
review must be filed in the D.C. Circuit: (i) when the agency action
consists of ``nationally applicable regulations promulgated, or final
actions taken, by the Administrator,'' or (ii) when such action is
locally or regionally applicable, but ``such action is based on a
determination of nationwide scope or effect and if in taking such
action the Administrator finds and publishes that such action is based
on such a determination.'' For locally or regionally applicable final
actions, the CAA reserves to the EPA complete discretion whether to
invoke the exception in (ii) described in the preceding sentence.\2\
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    \2\ Sierra Club v. EPA, 47 F.4th 738, 745 (D.C. Cir. 2022)
(``EPA's decision whether to make and publish a finding of
nationwide scope or effect is committed to the agency's discretion
and thus is unreviewable''); Texas v. EPA, 983 F.3d 826, 834-35 (5th
Cir. 2020).
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    This action is ``nationally applicable'' within the meaning of CAA
section 307(b)(1). The final rule governs the EPA's promulgation of
emission guidelines under CAA section 111(d), which are nationally
applicable regulations for which judicial review is available only in
the U.S. Court of Appeals for the District of Columbia (D.C. Circuit)
pursuant to CAA section 307(b)(1).\3\ Moreover, it revises the
generally applicable, nationally consistent implementing regulations
that govern the development and submission for all states of state
plans and the EPA's development of Federal plans pursuant to EGs under
CAA section 111(d), as well as the EPA's review of states' plans.
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    \3\ See, e.g., Nat'l Waste & Recyling Ass'n v. EPA, No. 16-1371
(D.C. Cir. 2016) (consolidated challenges to the CAA section 111(d)
emissions guidelines for municipal solid waste landfills in the D.C.
Circuit); Am. Lung Ass'n v. EPA, 985 F.3d 914 (D.C. Cir. 2021)
(consolidated challenges to, among other things, the CAA section
111(d) emission guidelines for fossil fuel-fired electric generating
units known as the Affordable Clean Energy Rule).
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    In the alternative, to the extent a court finds this final action
to be locally or regionally applicable, the Administrator is exercising
the complete discretion afforded to him under the CAA to make and
publish a finding that this action is based on a determination of
``nationwide scope or effect'' within the meaning of CAA section
307(b)(1).\4\ As explained above, this final action is revising a
single set of nationally consistent implementing regulations that apply
to every state that must develop a state plan submission pursuant to
CAA section 111(d) and an EPA-issued EG, as well as apply to the EPA
when it reviews state plan submissions. The regulations also govern the
EPA's development of EGs pursuant to CAA section 111(d), which apply to
every state that contains designated facilities.
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    \4\ In deciding whether to invoke the exception by making and
publishing a finding that an action is based on a determination of
nationwide scope or effect, the Administrator takes into account a
number of policy considerations, including his judgment balancing
the benefit of obtaining the D.C. Circuit's authoritative
centralized review versus allowing development of the issue in other
contexts and the best use of agency resources.
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    The Administrator finds that this is a matter on which national
uniformity in judicial resolution of any petitions for review is
desirable, to take advantage of the D.C. Circuit's administrative law
expertise, and to facilitate the orderly development of the law under
the Act. The Administrator also finds that consolidated review of this
action in the D.C. Circuit will avoid piecemeal litigation in the
regional circuits, further judicial economy, and eliminate the risk of
inconsistent results, and that a nationally consistent approach to
implementation of EGs pursuant to CAA section 111(d) constitutes the
best use of agency resources.
    For these reasons, this final action is nationally applicable or,
alternatively, the Administrator is exercising the complete discretion
afforded to him by the CAA and finds that this final action is based on
a determination of nationwide scope or effect for purposes of CAA
section 307(b)(1) and is publishing that finding in the Federal
Register. Under section 307(b)(1) of the CAA, petitions for judicial
review of this action must be filed in the United States Court of
Appeals for the District of Columbia Circuit by January 16, 2024. Under
CAA section 307(b)(2), the requirements established by this final rule
may not be challenged separately in any civil or criminal proceedings
brought by the EPA to enforce the requirements.
    Additionally, pursuant to CAA section 307(d)(1)(V), the
Administrator determines that this action is subject to the provisions
of CAA section 307(d). The EPA made this determination at proposal and
has complied with the applicable procedural requirements in the course
of this rulemaking. Section 307(d)(1)(V) of the CAA provides that the
provisions of CAA section 307(d) apply to ``such other actions as the
Administrator may determine.'' Section 307(d)(7)(B) of the CAA further
provides that ``[o]nly an objection to a rule or procedure which was
raised with reasonable specificity during the period

for public comment (including any public hearing) may be raised during
judicial review.'' This section also provides a mechanism for the EPA
to convene a proceeding for reconsideration, ``[i]f the person raising
an objection can demonstrate to the Administrator that it was
impracticable to raise such objection within [the period for public
comment] or if the grounds for such objection arose after the period
for public comment (but within the time specified for judicial review)
and if such objection is of central relevance to the outcome of the
rule.'' Any person seeking to make such a demonstration should submit a
Petition for Reconsideration to the Office of the Administrator, U.S.
Environmental Protection Agency, Room 3000, WJC South Building, 1200
Pennsylvania Ave. NW, Washington, DC 20460, with a copy to both the
person listed in the preceding FOR FURTHER INFORMATION CONTACT section,
and the Associate General Counsel for the Air and Radiation Law Office,
Office of General Counsel (Mail Code 2344A), U.S. Environmental
Protection Agency, 1200 Pennsylvania Ave. NW, Washington, DC 20460.
    The EPA notes that the individual regulatory provisions it is
revising or finalizing in this action are severable from one another
because each is supported by an independent rationale. That is, the
individual subsections within each of the sections of subpart Ba are
generally justified independently and are therefore severable for
purposes of judicial review.

II. Background

A. What is the statutory authority for this action?

    The statutory authority for this action is provided by CAA section
111 (42 U.S.C. 7411). As described further in the next section, CAA
section 111 requires the EPA to establish standards of performance for
certain categories of stationary sources that, in the Administrator's
judgment, ``cause[ ], or contribute[] significantly to, air pollution
which may reasonably be anticipated to endanger public health or
welfare.'' CAA section 111(b) provides the EPA's authority to regulate
new and modified sources, while CAA section 111(d) directs the EPA to
``prescribe regulations which shall establish a procedure'' for states
to submit plans to the EPA that establish standards of performance for
existing sources of certain air pollutants to which a standard would
apply if such existing source were a new source. The EPA addresses its
obligation under CAA section 111(d) to establish a procedure for states
to submit plans both through its promulgation of general implementing
regulations, including those addressed by this action, and through
promulgation of EGs for specific source categories. Additional
statutory authority for this action is provided by section 301 of the
CAA (42 U.S.C. 7601), which contains general provisions for the
administration of the CAA, including the authority for the
Administrator to ``prescribe such regulations as are necessary to carry
out [the] functions'' of the CAA under section 301(a)(1).

B. What is the background for this action?

    Clean Air Act section 111(d) governs the establishment of standards
of performance for existing stationary sources. CAA section 111(d)
directs the EPA to ``prescribe regulations which shall establish a
procedure similar to that provided by [CAA section 110]'' for states to
submit state plans that establish standards of performance for existing
sources of certain air pollutants to which a standard of performance
would apply if such an existing source were a new source under CAA
section 111(b). Therefore, an existing source can only be regulated
under CAA section 111(d) if it belongs to a source category that is
regulated under CAA section 111(b). The EPA's implementing regulations
use the term ``designated facility'' to identify those existing
sources. See 40 CFR 60.21a(b).
    CAA section 111(b)(1)(A) requires that a source category be
included on the list for regulation if, ``in [the EPA Administrator's]
judgment it causes, or contributes significantly to, air pollution
which may reasonably be anticipated to endanger public health or
welfare.'' Once a source category is listed, CAA section 111(b)(1)(B)
requires that the EPA propose and then promulgate ``standards of
performance'' for new sources in such source category. CAA section
111(a)(1) defines a ``standard of performance'' as ``a standard for
emissions of air pollutants which reflects the degree of emission
limitation achievable through the application of the best system of
emission reduction which (taking into account the cost of achieving
such reduction and any nonair quality health and environmental impact
and energy requirements) the Administrator determines has been
adequately demonstrated.'' This provision requires the EPA to determine
both the best system of emission reduction (BSER) for the regulated
source category and the degree of emission limitation achievable
through application of the BSER. The EPA must then, under CAA section
111(b)(1)(B), promulgate standards of performance for new sources that
reflect that level of stringency.
    Once the EPA promulgates standards of performance for new sources
within a particular source category, the EPA is required, in certain
circumstances, to regulate emissions from existing sources in that same
source category.\5\ Under CAA section 111(d), the Agency has, to date,
issued EGs regulating five pollutants from six source categories that
are currently in effect (i.e., sulfuric acid plants (acid mist),
phosphate fertilizer plants (fluorides), primary aluminum plants
(fluorides), kraft pulp plants (total reduced sulfur), municipal solid
waste landfills (landfill gases)), and fossil fuel-fired electric
generating units (greenhouse gases [GHGs]). See ``Phosphate Fertilizer
Plants; Final Guideline Document Availability,'' 42 FR 12022 (March 1,
1977); ``Standards of Performance for New Stationary Sources; Emission
Guideline for Sulfuric Acid Mist,'' 42 FR 55796 (October 18, 1977);
``Kraft Pulp Mills, Notice of Availability of Final Guideline
Document,'' 44 FR 29828 (May 22, 1979); ``Primary Aluminum Plants;
Availability of Final Guideline Document,'' 45 FR 26294 (April 17,
1980); ``Emission Guidelines and Compliance Times for Municipal Solid
Waste Landfills,'' 81 FR 59276 (August 29, 2016); ``Repeal of the Clean
Power Plan; Emission Guidelines for Greenhouse Gas Emissions From
Existing Electric Utility Generating Units; Revisions to Emission
Guidelines Implementing Regulations,'' 84 FR 32520 (July 8, 2019)
(Affordable Clean Energy (ACE) Rule).6 7 Additionally, the

EPA recently proposed EGs addressing GHG emissions from two different
source categories. On November 15, 2021, the EPA proposed EGs to
regulate GHG emissions (in the form of methane limitations) from
sources in the oil and natural gas source category (86 FR 63110) and
provided a supplemental proposal for that sector on December 6, 2022
(87 FR 74702). On May 23, 2023, the EPA proposed to repeal the existing
EG for GHG emissions from certain fossil fuel-fired electric generating
units (the ACE Rule) and to promulgate a new EG in order to regulate
GHG emissions (in the form of carbon dioxide limitations) from existing
fossil fuel-fired electric generating units. 88 FR 33240. Finally, the
Agency has regulated additional pollutants from solid waste
incineration units under CAA section 129 and in accordance with CAA
section 111(d).\8\
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    \5\ In accordance with CAA section 111(d), states are required
to submit plans to establish standards of performance for existing
sources for any air pollutant: (1) the emission of which is subject
to a Federal New Source Performance Standard; and (2) which is
neither a pollutant regulated under CAA section 108(a) (i.e.,
criteria air pollutants such as ground-level ozone and particulate
matter, and their precursors, like volatile organic compound) or a
hazardous air pollutant regulated from the same source category
under CAA section 112. See also definition of ``designated
pollutant'' in 40 CFR 60.21a(a).
    \6\ The EPA has also issued several EGs that have subsequently
been repealed or vacated by the courts. The EPA regulated mercury
from coal-fired electric power plants in a 2005 rule that was
vacated by the D.C. Circuit, ``Standards of Performance for New and
Existing Stationary Sources: Electric Utility Steam Generating
Units; Final Rule,'' 70 FR 28606 (May 18, 2005) (Clean Air Mercury
Rule), vacated by New Jersey v. EPA, 517 F.3d 574 (D.C. Cir. 2008).
The EPA also issued CAA section 111(d) EGs regulating GHG emissions
from fossil fuel-fired electric power plants in a 2015 rule,
``Carbon Pollution Emission Guidelines for Existing Stationary
Sources: Electric Utility Generating Units; Final Rule,'' 80 FR
64662 (October 23, 2015) (Clean Power Plan). The EPA subsequently
repealed and replaced the 2015 rule with the ACE Rule.
    \7\ The ACE Rule was initially vacated by Am. Lung Ass'n v. EPA,
985 F.3d 914 (D.C. Cir. 2021). The Supreme Court subsequently
reversed and remanded the D.C. Circuit's opinion, West Virginia v.
EPA, 142 S. Ct. 2587 (June 30, 2022). On October 27, 2022, the D.C.
Circuit amended its judgement and recalled the partial mandate
vacating the ACE Rule, effectively reinstating ACE. Order, ALA v.
EPA, No. 19-1140, ECF No. 1970895.
    \8\ CAA section 129 directs the EPA Administrator to develop
regulations under CAA section 111 limiting emissions of nine air
pollutants from four categories of solid waste incineration units.
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    The mechanism for regulating designated facilities \9\ under CAA
section 111(d) differs from the mechanism for regulating new facilities
under CAA section 111(b). Pursuant to CAA section 111(b), the EPA
promulgates standards of performance that are directly applicable to
new, modified, and reconstructed facilities in a specified source
category. In contrast, CAA section 111(d) operates together with CAA
section 111(a)(1) to collectively establish and define roles and
responsibilities for both the EPA and the states in the regulation of
designated facilities. Under the statutory framework, the EPA has the
responsibility to determine the BSER for designated facilities, as well
as the degree of emission limitation achievable through application of
that BSER. The EPA identifies both the BSER and the degree of emission
limitation as part of an EG, which it may typically reflect as a
presumptive standard of performance or methodology for calculating a
presumptive standard of performance for designated facilities. States
use the EPA's presumptive standards of performance as the basis for
establishing requirements for designated facilities in their state
plans. In addition to standards of performance, CAA section 111(d)(1)
requires state plans to include provisions for the implementation and
enforcement of such standards. CAA section 111(d)(1) also requires the
EPA's regulations to permit states, in applying a standard of
performance to particular sources, to take into account the source's
remaining useful life and other factors, a process addressed in more
detail in section III.E of this preamble.
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    \9\ A ``designated facility'' is any existing facility which
emits an air pollutant, the emissions of which are subject to a
standard of performance for new stationary sources but for which air
quality criteria have not been issues and that is not included on a
list published under CAA section 108(a) or 112, and which would be
subject to a standard of performance for that pollutant if the
existing facility were a new facility. See 40 CFR 60.21a.
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    CAA section 111(d) directs the EPA to establish a procedure for the
submission of state plans, which the EPA addresses both through its
promulgation of general implementing regulations for section 111(d) and
through promulgation of EGs for specific source categories. While CAA
section 111(d)(1) authorizes states to develop state plans that
establish standards of performance and provides states with certain
discretion in determining the appropriate standards, CAA section
111(d)(2) provides the EPA a specific oversight role with respect to
such state plans. The states must submit their plans to the EPA, and
the EPA must evaluate each state plan to determine whether each plan is
``satisfactory.'' If a state fails to submit a plan or the EPA
determines that a state plan is not satisfactory, the EPA has the
``same authority'' to prescribe a Federal plan as it has to promulgate
a Federal Implementation Plan (FIP) under CAA section 110(c).
    In 1975, the EPA issued the first general implementing regulations
to prescribe the process for the adoption and submittal of state plans
for designated facilities under CAA section 111(d) (codified at 40 CFR
part 60, subpart B (subpart B)). 40 FR 53340 (November 17, 1975).
Responding to the direction to ``establish a procedure similar to that
provided by'' CAA section 110, in promulgating subpart B, the EPA
aligned the timing requirements for state and Federal plans under CAA
section 111(d) with the then-applicable timeframes for State
Implementation Plans (SIPs) and FIPs prescribed in CAA section 110, as
established by the 1970 CAA Amendments. The implementing regulations
were not significantly revised after their original promulgation in
1975 \10\ until 2019, when the EPA promulgated a new set of
implementing regulations codified at 40 CFR part 60, subpart Ba
(subpart Ba). 84 FR 32520 (July 8, 2019).
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    \10\ In 2012, the EPA revised several provisions of subpart B,
mainly to include allowance systems as a form of standard of
performance. 77 FR 9303 (February 16, 2012).
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    In promulgating subpart Ba in 2019, the EPA intended to update and
modernize the implementing regulations to align the procedures for CAA
section 111(d) state and Federal plans with CAA amendments made after
subpart B was first promulgated in 1975. Notably, subpart B did not
align either with CAA section 111(d) as amended by Congress in 1977 or
with the timelines in CAA section 110 as amended by Congress in 1990.
The EPA therefore considered it appropriate to update the implementing
regulations for CAA section 111(d) to make changes similar to CAA
section 110, given that section 111(d)(1) of the CAA directs the EPA to
``prescribe regulations which shall establish a procedure similar to
that provided by section 110'' of the CAA for states to submit plans to
the EPA. In promulgating subpart Ba, the EPA directly aligned the
timing requirements for CAA section 111(d) state and Federal plans (40
CFR 60.23a(a)(1) and 60.27a(c), respectively) with the timing
requirements for SIPs and FIPs under CAA section 110 (see CAA section
110(a)(1) and 110(c)(1), respectively).
    In promulgating subpart Ba, the EPA also added the definition of
``standard of performance'' (40 CFR 60.21a(f)) (defined under subpart B
as ``emission standard'' (40 CFR 60.21(f))) and the ``remaining useful
life'' provision (40 CFR 60.24a(e)) (referred under subpart B as the
``variance'' provision (40 CFR 60.24(f))). The EPA further added
required minimum administrative and technical criteria for inclusion in
state plans (40 CFR 60.27a(g)). Applying these criteria, the EPA
determines whether a state plan or portion of a plan submitted is
complete (referred to as a completeness review). Once a state plan or
portion of a plan is determined to be complete, the EPA must approve or
disapprove the plan or portions of the plan. For details on the EPA's
rationale for the promulgation of these provisions, see 84 FR 32520
(July 8, 2019).
    The EPA proposed minor revisions to the subpart Ba applicability
provision and is finalizing those revisions largely as proposed (see
section III.G.2.a. of this preamble). As finalized in 2019, subpart Ba
was applicable to any final 111(d) EG published, or the implementation
of which was ongoing, after July 8, 2019. The EPA proposed revisions to
this provision for clarity, including to

remove the phrase ``if implementation of such final guideline is
ongoing.'' \11\ It did not propose to change the already-established
applicability date. At the time of promulgation of this rule, there are
no final EGs that have been published after July 8, 2019, so subpart Ba
will not retroactively apply to the implementation of any EG.
Specifically, the final EG for greenhouse gas emissions from existing
electric utility generating units that was included in the ACE Rule was
published on July 8, 2019; \12\ thus, subpart Ba as revised will not
apply to that EG. Regardless, the EPA proposed to repeal the ACE Rule
on May 23, 2023,\13\ and intends to finalize its repeal, at which point
neither states nor the EPA will have any obligations under the ACE Rule
and the potential applicability of subpart Ba to this EG will be moot.
In contrast, the EPA has recently proposed two EGs that would regulate
GHG emissions from designated facilities in the oil and natural gas
industry (86 FR 63110, November 15, 2021; 87 FR 74702, December 6,
2022) and in the power sector (88 FR 33240, May 23, 2023). If those EGs
are finalized and to the extent that the final EGs do not contain EG-
specific requirements superseding subpart Ba provisions, subpart Ba as
revised in this action will apply. Subpart B continues to apply to CAA
section 111 EGs promulgated on or prior to July 8, 2019, and to EGs
issued pursuant to CAA section 129.
---------------------------------------------------------------------------

    \11\ 87 FR 79176, 79208-09 (Dec. 23, 2022). As explained in
section III.G.2.a. of this preamble, the EPA is finalizing the
removal of this phrase from 40 CFR 60.20a(a).
    \12\ 84 FR 32520 (July 8, 2019).
    \13\ ``New source Performance Standards for Greenhouse Gas
Emissions From New, Modified, and Reconstructed Fossil Fuel-Fired
Electric Generating Units; Emission Guidelines for Greenhouse Gas
Emissions From Existing Fossil Fuel-Fired Electric Generating Units;
and Repeal of the Affordable Clean Energy Rule,'' 88 FR 33240 (May
23, 2023).
---------------------------------------------------------------------------

    In January 2021, the D.C. Circuit vacated several provisions of
subpart Ba related to timelines for state plans and Federal plans. Am.
Lung Ass'n v. EPA, 985 F.3d 914, 991. (D.C. Cir. 2021) (ALA).\14\ In
this vacatur, the court identified several flaws in the EPA's rationale
for extending CAA section 111(d) state and Federal plan timelines.
First, the court found that the EPA erred in adopting the timelines for
SIPs and FIPs in CAA section 110 without meaningfully addressing the
differences in the scale of effort required for development and
evaluation of CAA section 110 SIPs, as compared with the scale of
effort needed for CAA section 111(d) state plans. Id. at 992-93. The
court also concluded that in promulgating the timelines in subpart Ba,
the EPA failed to justify why the shorter deadlines under subpart B
were unworkable. Id. at 993. Further, the court held that the EPA was
required to consider the effect of its subpart Ba timelines on public
health and welfare, consistent with the statutory purpose of CAA
section 111(d). In the court's view, the EPA's ``complete failure to
say anything at all about the public health and welfare implications of
the extended timeframes'' meant that the EPA failed to consider an
important aspect of the problem. Id. at 992 (citing Motor Vehicle Mfrs.
Ass'n of U.S., Inc. v. State Farm Mut. Auto. Ins. Co. 463 U.S. 29, 43
(1983)).
---------------------------------------------------------------------------

    \14\ The Supreme Court subsequently reversed and remanded the
D.C. Circuit's opinion. West Virginia v. EPA, 142 S.Ct. 2587 (June
30, 2022). However, no Petitioner sought certiorari on, and the
Supreme Court's West Virginia decision did not implicate, the D.C.
Circuit's vacatur of portions of subpart Ba. See Amended Judgment,
ALA v. EPA, No. 19-1140 (D.C. Cir. October 27, 2022), ECF No.
1970898 (ordering that petitions for review challenging the timing
portion of implementing regulations be granted).
---------------------------------------------------------------------------

    Based on these reasons, the court vacated the timeline for state
plan submissions after publication of a final EG (40 CFR 60.23a(a)(1)),
the EPA's deadline for taking action on state plan submissions (40 CFR
60.27a(b)), the EPA's deadline for promulgating a Federal plan (40 CFR
60.27a(c)), and the timeline associated with requirements for
increments of progress (IoPs; 40 CFR 60.24 (a(d)). Because of the
vacatur, subpart Ba currently does not provide generally applicable
timelines for state plan submissions, a deadline for the EPA's action
on state plan submissions, a deadline for the EPA's promulgation of a
Federal plan, or a timeline associated with requirements for IoPs. The
EPA notes that while it is finalizing generally applicable timelines
for the implementing regulations, a particular EG may supersede those
generally applicable timelines with its own specific timelines. 40 CFR
60.20a(a)(1). This may be appropriate, for example, based on the
complexity of regulating a particular source category, such as a
category with a large number of disparate facilities to be regulated.

C. What changes did we propose?

    On December 23, 2022, the EPA proposed several revisions to subpart
Ba both to address the vacatur of the timing provisions by the D.C.
Circuit in ALA and to further improve the state and Federal plan
development and implementation process. See 87 FR 79176 (December 23,
2022). In response to the ALA decision, the EPA proposed timeframes for
(1) state plan submittal, (2) the timeline for the EPA to determine
completeness of state plans, (3) the EPA's action on state plan
submissions, (4) the EPA's promulgation of a Federal plan, and (5)
requirements to establish IoPs. Additionally, the EPA proposed to
remove the publication in the Federal Register of a ``finding of
failure to submit'' as the starting point for the clock to promulgate a
Federal plan.
    In addition, the EPA proposed revisions to subpart Ba that would
enhance the provision of reasonable notice and opportunity for public
participation by requiring that states, as part of the state plan
development or revision process, undertake outreach and meaningful
engagement with a broad range of pertinent stakeholders. The EPA
proposed to define pertinent stakeholders as including communities most
affected by and vulnerable to the impacts of the plan or plan revision.
Increased vulnerability, as described in the proposal, may be
attributable, among other reasons, to both an accumulation of negative
and lack of positive environmental, health, economic, or social
conditions within these populations or communities.
    To improve flexibility and efficiency in the submission, review,
approval, and implementation of state plans, the EPA proposed to
include the following mechanisms in subpart Ba, all of which currently
exist under CAA section 110: (1) partial approval/disapproval, (2)
conditional approval, (3) allowance for parallel processing, (4) a
mechanism for the EPA to call for plan revisions, and (5) an error
correction mechanism.
    The EPA also proposed revisions to the existing regulations
governing the ``remaining useful life and other factors'' (RULOF)
provision of the statute. These proposed revisions were intended to
promote clarity and increase consistency in situations where states or
the EPA consider RULOF when applying standards of performance to
individual sources and to ensure that such standards fulfill the
statutory requirements of CAA section 111(d).
    Finally, the EPA proposed to require electronic submissions of
state plans, as well as additional modifications and clarifications to
subpart Ba. In particular, the EPA proposed clarifying amendments to
the subpart Ba definition of standard of performance, along with a
revised interpretation of CAA section 111(d) with respect to
permissible compliance flexibilities. The EPA proposed to determine
that, under appropriate circumstances, the Agency may approve state
plans that authorize sources to meet their emission limits in the
aggregate, such as through standards that permit compliance via

trading or averaging. In doing so, the EPA also proposed to conclude
that CAA section 111 does not limit the BSER to controls that can be
applied at and to the source.
    The EPA did not reopen any subpart Ba requirements other than the
specific provisions that the EPA explicitly proposed to revise in the
December 2022 notice of proposed rulemaking. Any comments received on
the proposal that did not relate to the proposed revisions or additions
are considered out of the scope of this action.

D. What outreach and engagement did the EPA conduct?

    The EPA conducted both pre- and post-proposal outreach and
meaningful engagement events with environmental justice (EJ)
communities, small businesses, states, and Tribes. On July 7 and July
11, 2022, the EPA conducted two pre-proposal webinars for states
addressing meaningful engagement for pertinent stakeholders, and on
July 26, 2022, the Agency conducted a pre-proposal webinar for EJ
communities and other key stakeholders about potential requirements for
states to conduct meaningful engagement in developing their state
plans. The EPA emailed an announcement of the subpart Ba proposal to
Tribal nations and environmental justice communities via existing
listservs on December 15, 2022. Post-proposal outreach during the
public comment period with environmental justice communities included
participation on the January 24, 2023 Environmental Justice National
call and the January 26, 2023 National Tribal Air Association call. The
EPA also conducted a public training webinar on January 31, 2023, for
environmental justice community members and their representatives.
Additionally, the EPA conducted post-proposal outreach with small
businesses through the Small Business Environmental Assistance Program
call on February 21, 2023, and with state environmental protection
associations including the Association of Air Pollution Control
Agencies on January 10, 2023, and the National Association of Clean Air
Agencies on February 8, 2023.

III. What actions are we finalizing and what is our rationale for such
decisions?

    This action finalizes amendments to subpart Ba, including the
timing requirements for state plan submittal, the EPA's action on state
plan submissions, the EPA's promulgation of a Federal plan, and the
establishment of IoPs; the addition of five regulatory mechanisms to
improve state plan processing: (1) partial approval/disapproval, (2)
conditional approval, (3) allowance for parallel processing, (4) a
mechanism for the EPA to call for plan revisions, and (5) an error
correction mechanism; new requirements for meaningful engagement with
pertinent stakeholders; and amended requirements for states' and the
EPA's consideration of RULOF in applying a standard of performance in
certain circumstances. This action also finalizes amendments to the
subpart Ba definition of ``standard of performance'' and finalizes
clarifications associated with CAA section 111(d) compliance
flexibilities. Finally, this action finalizes requirements for the
electronic submission of state plans and several other clarifications
and minor revisions to the implementing regulations. While the EPA is
finalizing most amendments as proposed, in response to comments
submitted on the proposal, the EPA is extending the state plan
submittal timeline and the timeline for requirement of IoPs; providing
for additional flexibility and guidance for meaningful engagement; as
well as revising and streamlining the requirements for accounting for
RULOF in applying a less-stringent standard. There are also other
provisions that we are finalizing with slight revisions relative to
proposal. Further detail is provided in the following sections of this
preamble and additional detailed responses to comments are located in
the response to comment document (RTC).
    While this action amends the generally applicable requirements of
subpart Ba, the EPA has recognized that, under certain circumstances,
some provisions of the implementing regulations may not fit the needs
of a specific EG. Therefore, the existing implementing regulations
provide that each EG may include specific implementing provisions in
addition to or that supersede the requirements of subpart Ba. 40 CFR
60.20a(a)(1). The EPA will address source category-specific
circumstances or facts that are not accommodated by the general
provisions of subpart Ba through a specific EG, as the time and
processes needed for development and adoption of state plans to
implement the EG may be affected by unique characteristics of a source
category. For example, if a proposed EG addresses a particularly large
and complex source category that necessitates a relatively long
timeframe for state planning, the EPA may provide a state plan
submission deadline that is longer than the 18 months being finalized
for subpart Ba.\15\
---------------------------------------------------------------------------

    \15\ See, e.g., 88 FR 33240, 33402-03 (May 23, 2023) (proposing
a 24-month state plan submission deadline for the EG for GHG
emissions from fossil fuel-fired electric generating units).
---------------------------------------------------------------------------

A. Revised Implementing Timelines

    As described in section II.A. of this preamble, the subpart Ba
timing requirements were vacated by the D.C. Circuit in the ALA
decision. These vacated timing requirements include: the timeline for
state plan submissions, the timeline for the EPA to act on a state
plan, the timeline for the EPA to promulgate a Federal plan, and the
timeline that dictates when state plans must include IoPs. These
timelines are all critical to ensuring that the emission reductions
anticipated by the EPA when promulgating an EG become federally
enforceable measures that are timely implemented by the designated
facilities.
    The EPA proposed the following timelines to replace those vacated
in ALA (87 FR 79176, Dec. 23, 2022): 15 months for state plan
submissions after publication of a final EG; 60 days after submission
for the EPA to determine if a plan is complete; 12 months for the EPA
to take final action on a complete state plan (i.e., approve,
disapprove); 12 months for the EPA to promulgate a Federal plan either
after the state plan submission deadline if a state has failed to
submit a complete plan, or after the EPA's disapproval of a state plan
submission; and requiring state plans to include IoPs if the plan
requires final compliance with standards of performance later than 16
months after the plan submission deadline.\16\
---------------------------------------------------------------------------

    \16\ See 87 FR 79176, 79181-90 (Dec. 23, 2022).
---------------------------------------------------------------------------

    The EPA received numerous comments on these proposed timelines,
most of which expressed support for timelines longer than those
proposed. Some commenters asserted that the ALA decision does not
direct the EPA to necessarily reduce timelines from those vacated, only
to justify the timelines more fully. In particular, most commenters
expressed the need for a longer state plan submittal timeline in order
to accommodate state regulatory processes associated with plan
submittals (i.e., legislative and/or administrative state processes),
as well as to accommodate technical development of the plans and to
implement the proposed meaningful engagement requirements. However, a
few commenters noted that the EPA should not accommodate all lengthy
state administrative processes that would unnecessarily postpone
emission-reduction obligations. Some

commenters asserted that if the EPA were to finalize the state plan
submittal timeline as proposed, the EPA should include a mechanism in
the rule for states to request for extensions for state plan
submittals.
    While some commenters also asserted the need for longer timelines
associated with the EPA's obligations to take action on a state plan
submittal and to promulgate a Federal plan when required, as well as
allowing a longer timeline before IoPs are required in the state plans,
other commenters supported the proposed timelines for these milestones
based, among other concerns, on the need for timely protection of
health and welfare and in consideration of the EPA's ability to extend
timelines if warranted in a particular EG.
    In consideration of these comments and for the reasons described in
detail in the sections that follow, the EPA is finalizing extended
timelines from those proposed for submission of state plans, for
significant state plan revisions, and for when IoPs must be considered
for inclusion in state plans. The EPA is finalizing the remaining
timelines as proposed. The EPA determined that these timelines will
appropriately balance the need to reasonably accommodate the processes
generally required by states and the EPA to develop, evaluate, and
adopt plans to effectuate the EG with the need to ensure that
designated facilities control emissions of dangerous pollutants as
expeditiously as reasonably possible, consistent with the health and
welfare-based objectives of CAA section 111(d). A summary of the
timelines finalized in this action is shown in Table 1.
    The final subpart Ba timelines are applicable to any final EG
published pursuant to CAA section 111(d) after July 8, 2019, including,
if finalized, those recently proposed to regulate GHG emissions from
sources in the oil and natural gas industry (86 FR 63110, November 15,
202187 and FR 74702, December 6, 2022) and those proposed to regulate
GHG emissions from fossil fuel-fired electric generating units (88 FR
33240, May 23, 2023), to the extent that the final EGs do not contain
provisions superseding any of these timelines in subpart Ba.\17\
---------------------------------------------------------------------------

    \17\ Under each of these EGs the EPA proposed to supersede the
15-month state plan submittal timeline in proposed subpart Ba based
on the size and complexity of the source sectors at issue.

Table 1--Final 40 CFR Part 60, Subpart Ba, Timeline Compared With Those Initially Proposed, Vacated From Subpart
                                             Ba, and From Subpart B
----------------------------------------------------------------------------------------------------------------
                                    2023 Subpart Ba     2022 Subpart Ba    Subpart Ba (2019)
          Process step                   final             proposal        vacated timelines   Subpart B (1975)
----------------------------------------------------------------------------------------------------------------
State Plan submittal after        18 months.........  15 months.........  36 months.........  9 months.
 publication of EG in the
 Federal Register.
State Plan completeness           60 days after       60 days after       *6 months after     N/A.
 determination.                    State Plan          State Plan          State Plan
                                   submission.         submission.         submission.
State Plan evaluation...........  12 months after     12 months after     12 months after     4 months after
                                   completeness.       completeness.       completeness.       State Plan
                                                                                submittal
                                                                                deadline.
EPA Federal Plan promulgation...  12 months after     12 months after     24 months after     6 months after
                                   failure to submit   failure to submit   finding of          State Plan
                                   or disapproval.     or disapproval.     failure to submit   submittal
                                                                           or disapproval.     deadline.
Requirements for Increments of    If compliance is    If compliance is    If compliance is    If compliance is
 Progress after submittal          >20 months.         >16 months.         >24 months.         >12 months.
 deadline.
----------------------------------------------------------------------------------------------------------------
* Although the timeline for the state plan completeness determinations was not vacated, the EPA has evaluated
  this timeline light of the court vacatur of the related timelines.

    As described in greater detail in section II. of this preamble, the
D.C. Circuit's vacatur of the extended timelines in subpart Ba was
based both on the EPA's failure to substantiate the necessity for the
additional time at each step of the administrative process, and the
EPA's failure to address how those extended implementation timelines
would impact public health and welfare. Accordingly, the EPA has
evaluated these factors and is finalizing timelines, as described in
the following sections, based on the minimum administrative time
reasonably necessary for each step in the implementation process, thus
minimizing impacts on public health and welfare by proceeding as
expeditiously as reasonably possible while accommodating the time
needed for states or the EPA to develop an effective plan. This
approach addresses both aspects of the ALA decision because the EPA and
states will take no longer than necessary to develop and adopt plans
that impose requirements consistent with the overall objectives of CAA
section 111(d).
    The EPA acknowledges these timelines are not identical to those for
SIPs under CAA section 110. This is consistent with the requirement of
CAA section 111(d) that the EPA promulgate a procedure ``similar'' to
that of CAA section 110, rather than an identical procedure. This is
also consistent with the ALA decision, which requires the EPA to
``engage meaningfully with the different scale'' of CAA section 111(d)
and 110 plans. 985 F.3d at 993. In proposing the revised timelines, the
EPA evaluated each step of the state plan implementation process to
independently determine the appropriate duration needed to accomplish a
given step as part of the overall process. After receiving comments on
the proposed timelines, the EPA again evaluated each step in light of
the new information; the timelines being finalized in this action
represent the Agency's revised assessment of the most reasonably
expeditious timelines that are appropriate to provide as a default for
EGs under these generally applicable implementing regulations.
    The EPA recognizes that, under certain circumstances, the timelines
being finalized in this action may not fit the needs of a specific EG
because of the specific characteristics of an EG. The EPA will address
source category-specific circumstances or facts that are not
accommodated by the timelines of subpart Ba through a specific EG.
Examples of circumstances that may require consideration for different

timelines could include EGs that require states to perform extensive
engineering and/or economic analyses before submitting their plans; EGs
with an exceptional need to expedite implementation (e.g., in order to
address immediate health and welfare impacts); EGs that apply to an
extraordinary number of disparate designated facilities; or EGs that
are novel and/or unusually complex. For situations like these, 40 CFR
60.20a(a)(1) provides that an EG may supersede any aspect of the
implementing regulations, including the implementation timelines. It is
within the EPA's discretion to determine whether a proposed change in
implementation time may be justified within an individual EG based on
these or other appropriate factors. For EGs that supersede
implementation timelines, the EPA will, in the EG, both provide a
justification for the differing timelines and address how the change in
timeline will impact health and welfare.
1. State Plan Submission Timelines
    This section discusses the amount of time states will have to
submit plans and plan revisions to the EPA following the publication of
a final or revised EG in the Federal Register. As described in further
detail in section III.E of this preamble, under CAA section 111(d), the
EPA first determines a BSER and the degree of emission limitation for
designated facilities and promulgates these determinations in an EG.
CAA section 111(a)(1), 40 CFR 60.22a(b)(5). It is then each state's
obligation to submit a plan to the EPA which establishes standards of
performance based on the EG for each designated facility. See CAA
section 111(d)(1), 40 CFR 60.24a(c). The implementing regulations
promulgated in 1975 under subpart B provide that states have 9 months
to submit a state plan after publication of a final EG. 40 CFR
60.23(a)(1). In 2019, the EPA promulgated subpart Ba and provided 3
years for states to submit plans or plan revisions for subsequently
promulgated or revised EGs, consistent with the timelines provided for
submission of SIPs pursuant to CAA section 110(a)(1). This 3-year
timeframe was vacated by the D.C. Circuit in the ALA decision, and thus
currently there is no applicable deadline for state plan submissions
and revisions required under EGs subject to subpart Ba.
    As laid out in the notice of proposed rulemaking and summarized
below, in evaluating the appropriate timeline for plan submittal to
replace the vacated provisions in subpart Ba, the EPA reviewed steps
that states need to carry out to develop, adopt, and submit a state
plan to the EPA, and its history in implementing EGs under the timing
provisions of subpart B. The EPA further evaluated the statutory
deadlines and processes for relatively comparable state plans under CAA
section 129, and attainment planning SIPs submitted pursuant CAA
sections 189(a)(2)(B) and 189(b)(2) for the 2012 National Ambient Air
Quality Standards (NAAQS) for fine particulate matter
(PM2.5). 78 FR 3085 (January 15, 2013). Finally, the EPA
incorporated consideration of the ALA decision addressing expediency in
implementation of EGs for protection of public health and welfare.
    To develop a CAA section 111(d) state plan, a state must complete a
series of steps to ensure that the plan will meet all applicable
requirements. Subpart Ba specifies the elements that must be included
in a state plan submission (see 40 CFR 60.24a, 60.25a, 60.26a) as well
as certain processes that a state must undertake in adopting and
submitting a plan (see 40 CFR 60.23a). In addition to the requirements
of these implementing regulations, there are also state-specific
processes applicable to the development and adoption of a state plan,
including the administrative processes (e.g., permitting processes,
regulatory development, legislative approval) necessary to develop and
adopt enforceable standards of performance. State plan development
generally involves several phases, including providing notice that the
state agency is considering adopting a rule; taking public comment; and
approving or adopting a final rule. The process required to formally
adopt a rule at the state level differs from state to states.\18\
---------------------------------------------------------------------------

    \18\ In many states, the agency must submit its rule to a
particular independent commission or the legislature for review and
approval before the rule is finally adopted. Generally, adopted
rules are filed with a state entity, such as the secretary of state,
and eventually published in a register and placed into the state's
administrative code. State law establishes when an adopted rule is
effective.
---------------------------------------------------------------------------

    As previously mentioned, subpart B provides 9 months for states to
submit plans after publication of a final EG. The EPA's review of
state's timeliness for submitting CAA section 111(d) plans under the 9-
month timeline indicated that most states either did not submit plans
or submitted plans that were substantially late.\19\ The EPA also noted
that the plans submitted under subpart B were not subject to additional
requirements for meaningful engagement and consideration of RULOF,
which may add time to the state development process relative to plans
developed and submitted under subpart B. For these reasons, the EPA
found that 9 months is not a reasonable amount of time for most states
to adequately develop a plan for an EG.
---------------------------------------------------------------------------

    \19\ The EPA reviewed the information available in 40 CFR part
62. The supporting information reviewed is available at Docket ID
No. EPA-HQ-OAR-2021-0527. Part 62 codifies the Administrator's
approval and disapproval of state plans for the control of
pollutants and facilities under CAA section 111(d), and under CAA
section 129 as applicable, and the Administrator's promulgation of
such plans or portions of plans thereof.
---------------------------------------------------------------------------

    To help inform the proposal for the state plan submission deadline,
the EPA also reviewed CAA section 129's statutory deadline and
requirements for state plans, and the timeliness and responsiveness of
states under CAA section 129 EGs. CAA section 129 references CAA
section 111(d) in many instances, creating considerable overlap in the
functionality of the programs. The processes for CAA sections 111(d)
and 129 are similar in that states are required to submit plans to
implement and enforce the EPA's EGs. However, there are some key
distinctions between the two programs, most notably that CAA section
129(b)(2) specifies that state plans be submitted no later than 1 year
from the promulgation of a corresponding EG, whereas the statute does
not specify a particular timeline for state plan submissions under CAA
section 111(d). Moreover, CAA section 129 plans are required by statute
to be at least as protective as the EPA's EGs, without exception. CAA
section 129(b)(2). While CAA section 111(d) permits states to take into
account remaining useful life and other factors to set less stringent
standards for particular sources. This suggests that the development of
a CAA section 111(d) plan could involve more complicated analyses than
a CAA section 129 plan and that a longer timeframe is likely reasonable
for state plans under CAA section 111(d) than the 1-year timeframe the
statute provides under CAA section 129.
    Additionally, the EPA found that a considerable number of states
have not made timely state plan submissions in response to previous CAA
section 129 EGs. In instances where states submitted CAA section 129
plans, a significant number of states submitted plans between 14 to 17
months after the promulgated EG.\20\ This again suggests that states
will typically need more than

one year to develop a state plan to implement an EG.
---------------------------------------------------------------------------

    \20\ The EPA reviewed the information available in 40 CFR part
62. The supporting information reviewed is available at Docket ID
No. EPA-HQ-OAR-2021-0527. Part 62 codifies the Administrator's
approval and disapproval of state plans for the control of
pollutants and facilities under CAA section 111(d), and under CAA
section 129 as applicable.
---------------------------------------------------------------------------

    In the 2019 promulgation of subpart Ba, the EPA mirrored CAA
section 110 by giving states 3 years to submit plans. As previously
described, the D.C. Circuit faulted the EPA for adopting the CAA
section 110 timelines without accounting for the differences in scale
and scope between CAA section 110 and 111(d) plans. Therefore, in
proposing the revised timelines the EPA closely evaluated other
statutory deadlines and requirements for state implementation plans to
determine what is feasible for a CAA section 111(d) state plan
submission timeline. The EPA specifically focused on statutory SIP
submission deadlines and requirements in the context of attainment
plans for the 2012 PM2.5. NAAQS under CAA section 189
because it provided a comparable process. CAA section 189(a)(2)(B)
requires states to submit attainment planning SIPs within 18 months
after an area is designated nonattainment and there is a record of
successful state submittals pursuant to this timeline. The 2012
PM2.5. NAAQS attainment plans were, in most cases, more
complicated for states to develop when compared to a typical plan that
may be required under CAA sections 111(d). For example, attainment
plans require states to determine how to control a variety of sources,
based on extensive modeling and analyses, in order to bring a
nonattainment area into attainment of the PM2.5 NAAQS by a
specified date. Identification of contributing emission sources and the
development of effective control strategies can be challenging because
particulate matter pollution is comprised of both primary emissions and
secondary particle formation. By contrast, under CAA section 111(d), it
is clear which designated facilities are subject to a state plan, in
general what control methods are available for the designated pollutant
from that facility, and that the standards of performance for these
sources must reflect the level of stringency for the facility as
determined by the EG unless a state chooses to account for RULOF.
    Informed by these analyses, the EPA proposed to require that each
state adopt and submit to the Administrator a plan for the control of
the designated pollutant(s) to which the EG applies within 15 months of
publication of a final EG. Some commenters supported the proposed
timeline based on the need for urgency in achieving the emission
reductions targeted by an EG. Additionally, some commenters noted that,
in comparison with NAAQS SIP requirements, states are generally well-
positioned to address the source sectors historically regulated under
CAA section 111(d) and have access to information about control
strategies and regulatory approaches for controlling emissions. Most
commenters on this issue were state agencies or other state-related
entities that generally expressed the need for a longer state plan
submittal timeline in order to accommodate state regulatory processes
associated with plan submittals (i.e., legislative and/or
administrative state processes), as well as to accommodate technical
development of the plans and to implement the proposed meaningful
engagement requirements. Approximately 10 states responded to the EPA's
request with information about their state processes. The information
received indicates that states argued that they need anywhere from 15
months to 36 months to adopt and submit state plans. As discussed
further below, the EPA is finalizing a state plan submittal timeline of
18 months. It is doing so after consideration of comments received on
the proposal and recognizing the need to protect public health and
welfare. The EPA has determined that 18 months is the appropriate
timeline for these general implementing regulations; for a generic EG,
this represents a reasonable balance between providing states
sufficient time to develop and submit a plan that satisfies the
applicable requirements and ensuring that the emission reductions
contemplated in an EG are achieved as expeditiously as practicable.
Consistent with the existing regulations of subpart Ba, 40 CFR
60.20a(a)(1), the EPA may supersede this 18-month state plan submittal
timeline in an individual EG.
    The proposed 15-month submittal timeline was based on the EPA's
proposed determination that this was a reasonably expeditious deadline
that would provide states and stakeholders sufficient time to develop
and submit an approvable state plan. However, based on public comments
received, we no longer believe that 15 months will provide sufficient
time to complete the substantive and procedural requirements under
subpart Ba. For example, the EPA is revising subpart Ba to require that
states demonstrate meaningful engagement as part of their state plan
development. While the time needed to conduct meaningful engagement
will depend highly on the source category, the designated pollutant,
and the types of impacts associated with designated facilities and
potential controls, as well as on the pertinent stakeholders under a
given EG within each state, it is very likely to require additional
time relative to the existing public notice and hearing requirements
under CAA section 110 and subpart Ba. We received comments that 15
months would be insufficient time to identify pertinent stakeholders,
develop public participation strategies, and conduct outreach and
engagement. Some commenters also pointed out that adding requirements,
such as meaningful engagement and RULOF, without a corresponding
extension of time to develop plans may undermine states' abilities to
submit timely, approvable plans. While some commenters requested 36
months to submit state plans, several indicated that a minimum
timeframe of 18 months would be appropriate for a state plan under a
generic EG. Given the preponderance of comments suggesting that 15
months was not a reasonable amount of time to develop an approvable
state plan and in recognition of the need to promulgate a timeline that
achieves emission reductions as expeditiously as practicable, the EPA
believes 18 months is the most reasonable timeline to include in these
generally applicable implementing regulations.
    The EPA acknowledges that, as commenters asserted, state regulatory
and legislative processes and resources can vary significantly and
influence the time needed to develop and submit state plans (e.g.,
legislative procedures and timelines vary by state). Some commenters
opposed to a shorter state plan submission timeline asserted that they
need 36 months to complete their administrative and legislative
processes. However, because the CAA contains numerous, long-standing
requirements under other programs for states to develop and submit
plans within 18 months (or fewer),\21\ the EPA believes that states
should be well positioned to accommodate an 18-month submittal timeline
for plans under section 111(d). In designing a submittal deadline for
state plans, it is reasonable to look to what Congress has determined
are appropriate timelines for SIPs and to assume that states should be
able to accommodate comparable timelines under CAA section 111(d).
Indeed, some commenters recommend that the EPA not defer to lengthy
state administrative processes, and expressed concern that some states
have adopted, or may adopt, procedures that are longer than necessary
and that will unnecessarily postpone Federal emission-reduction
obligations. To this point, extending

state plan submittal timelines to account for any and all unique state
procedures would inappropriately delay reductions in emissions that
have been found under CAA section 111 to endanger health or the
environment.
---------------------------------------------------------------------------

    \21\ See, e.g., CAA sections 110(k)(5); 129; 179(d)(1); 189.
---------------------------------------------------------------------------

    Some commenters asserted that the ALA decision does not preclude
the EPA from adopting a 36-month time frame for state plan submittals
and that the Agency need only justify a longer timelines more fully.
However, the EPA recognizes that the D.C. Circuit, in ALA, faulted the
Agency for failing to consider the potential impacts to public health
and welfare associated with extending planning deadlines. In response,
the EPA is promulgating a state plan submittal timeline that reflects
the generally expeditious period of time for states to develop and
submit a plan per the corresponding emission guidelines that is both
comprehensive and legally sound. The EPA does not interpret the court's
direction to require a quantitative measure of impact, but rather
consideration of the importance of meeting the public health and
welfare goals when determining appropriate deadlines for implementation
of regulations under CAA section 111(d). Based on EPA's assessment of
the time it will take for states to develop and submit plans under
these general implementing regulations, both in the notice of proposed
rulemaking and this preamble and after consideration of comments
received, the EPA has determined that 18 months represents the
generally expeditious period of time.
    Some commenters stated that reduction of the designated pollutants
addressed by currently proposed emission guidelines (i.e., GHG) is not
urgent based on the fraction of global GHG reduced by currently
proposed emission guidelines, so a longer state plan timeline would be
justified. The EPA disagrees with the commenters' characterizations of
the threat posed by elevated concentrations of greenhouse gases in the
atmosphere. The EPA has determined that greenhouse gas air pollution
may reasonably be anticipated to endanger public health or welfare \22\
and has explained that ``scientific assessments, EPA analyses, and
documented observed changes in the climate of the planet and of the
U.S. present clear support regarding the current and future dangers of
climate change and the importance of GHG emissions mitigation.'' \23\
Moreover, subpart Ba applies to any EG promulgated after July 8, 2019,
not only to the recently proposed EGs addressing GHG emissions from two
source categories. The EPA regulates source categories, through EGs,
that emit pollutants the Agency has determined under CAA section 111(d)
to cause or significantly contribute to an endangerment of public
health or welfare. Accordingly, consistent with ALA, it is appropriate
for the EPA to set an expeditious but reasonable schedule in these
general provisions for state plan development and submission to ensure
that emission reductions occur in a timely manner.
---------------------------------------------------------------------------

    \22\ See, e.g., 80 FR 64510, 64530 (Oct. 23, 2015).
    \23\ 88 FR 33240, 33252 (May 23, 2023).
---------------------------------------------------------------------------

    Finally, some commenters asserted that if the EPA were to finalize
the state plan submittal timeline as proposed, the EPA should include a
mechanism in subpart Ba for states to ask for extensions of the state
plan submittal deadline. However, as we are providing additional time
for state plan submittals relative to proposal, we are not providing a
mechanism for states to request deadline extensions in subpart Ba.
Additionally, the EPA has the ability to supersede the timelines in
subpart Ba in individual EGs and will take into account any unique
considerations that may result in the need for longer or shorter
timelines on an EG-by-EG basis.
    In summary, while the EPA proposed a 15-month state plan submittal
timeline, after consideration of comments, the EPA is finalizing 40 CFR
60.23a(a)(1) to provide an 18-month timeline for the submission of
state plans following publication in the Federal Register of a final
EG. The EPA has determined that this is the generally expeditious
period in which states can create and submit a plan per the EPA's
corresponding EGs that is both comprehensive and legally sound. In
considering the appropriate timeline, the EPA has evaluated data from
previously implemented EGs and the statutory deadlines and data from
analogous programs (e.g., CAA sections 129 and 189). We have also
considered comments that some of the requirements the EPA had proposed
for subpart Ba would require additional time to implement, as well as
comments asserting that certain states need up to 36 months to complete
their administrative and legislative processes. While a reasonable
state plan submittal timeline must provide states sufficient time to
develop and submit plans that comport with the applicable requirements,
the EPA also believes that state processes should be able to
accommodate an 18-month timeline because the CAA already contains
numerous deadlines that require SIP submissions to be developed and
submitted to the Agency within 18 or fewer months. Thus, this finalized
timeline should provide states reasonable time to adopt and submit
approvable plans, and is also sufficiently expeditious to protect
against significant adverse impacts to health and welfare resulting
from foregone emission reductions during the state planning process.
Providing states sufficient time to develop feasible implementation
plans for their designated facilities that adequately address public
health and environmental objectives also ultimately helps ensure more
timely implementation of an EG, and therefore achievement in actual
emission reductions, than would an unattainable deadline. Because 18
months is an expeditious time period, it follows that the EPA has
appropriately considered the potential impacts to public health and
welfare associated with this extension of time by providing no more
time than the states reasonably need to ensure a plan is comprehensive
and timely.
    The EPA is also finalizing the proposed amendment to 40 CFR
60.27a(a) replacing the word ``shorten'' with ``amend''. The
applicability provision at 40 CFR 60.20a(a)(1) states that ``each
emission guideline may include specific provisions in addition to or
that supersede requirements of this subpart.'' However, the existing
provision in 40 CFR 60.27a(a) only provides for the Administrator to
``shorten the period for submission of any plan or plan revision or
portion thereof.'' To make these two provisions consistent in light of
the timelines for plan submission finalized in this action, the EPA is
replacing the word ``shorten'' with ``amend.'' One commenter opposed
the amendment stating there is no regulatory certainty for the state in
state plan submittal if the Administrator can simply change the
timeline as he deems necessary. However, the appropriate timeline would
undergo notice and comment rulemaking as the EG is proposed and
finalized so that states would have sufficient notice of the timeline.
To the extent the EPA considers deviating from this 18-month timeframe
in promulgating an EG in the future, the EPA will consider the public
health and welfare impacts associated with extending the state plan
submission timeline, consistent with the D.C. Circuit's direction in
ALA.
    The EPA is also finalizing two amendments to 40 CFR 60.28a(a),
which addresses plan revisions by the state. First, the EPA is
finalizing the proposed clarification that meaningful engagement
requirements apply to any significant plan revision by the state.
Second, the EPA is finalizing revisions

to the timeline for state plan revisions required in response to a
revised emission guideline. At proposal, the EPA indicated in the
revised regulatory text that it was proposing to shorten the timeline
for state plan revisions in this specific circumstance from three years
to 12 months.\24\ The EPA received comments on this proposed revision
asserting that the same process-related challenges that apply to
initial state plan submissions, including conducting meaningful
engagement and RULOF procedures and working through states'
administrative and legislative processes, also apply to state plan
revisions. Commenters requested that the EPA extend the timeline for
state plan revisions in response to revised emission guidelines; one
commenter specifically requested that the EPA leave it at 36 months.
However, the EPA anticipates that, in most instances, plan revisions
required in response to a revised emission guideline would be narrower
in scope than the initial state plan and would not require states to
reevaluate standards of performance or conduct significant new
analysis. For example, the EPA may revise an emission guideline to
provide for additional or updated monitoring or compliance protocols or
to clarify applicability provisions. In such instances, the full period
of time provided for initial state plan development and submission
would not be necessary.\25\ Thus, the EPA believes it is reasonable to
set a default timeline for the submission of state plan revisions in
these general implementing guidelines that is shorter than the timeline
for initial state plan submission. Because the EPA is providing an
additional three months for state plan submission in this final rule
relative to the proposed timeline (18 months versus 15 months), it is
finalizing a timeline for the submission of state plan revisions in
response to a revised emission guideline of fifteen months, which is
also three months longer than the twelve months proposed. Additionally,
in recognition that some state plan revisions in response to a revised
emission guideline may in fact be more complex or necessitate
additional analysis or rulemaking, the EPA is finalizing the provision
at 40 CFR 60.28a(a) to allow the Agency to determine a different
timeline for the submission of revised state plans, which it will
provide in the revised emission guideline.
---------------------------------------------------------------------------

    \24\
``Docket_memo_outlining_proposed_changes_to_regulatory_text.pdf,''
available at https://www.epa.gov/stationary-sources-air-pollution/adoption-and-submittal-state-plans-designated-facilities-40-cfr, as
well as Docket ID No. EPA-HQ-OAR-2021-0527-0002.
    \25\ The EPA's response to comments that the state plan
submission timelines should accommodate every state's unique
administrative and legislative processes is also relevant here and
is provided elsewhere in this section of the preamble.
---------------------------------------------------------------------------

2. Timeline for the EPA To Determine Completeness of State Plans
    Once a state plan has been submitted to the EPA, the EPA reviews
the plan for ``completeness'' to determine whether it includes certain
elements necessary to ensure that the EPA can substantively evaluate
the plan. The EPA determines completeness by comparing the state's
submission against the administrative and technical criteria specified
in subpart Ba to determine whether the submission contains the
specified elements (see 40 CFR 60.27a(g)(2) for completeness criteria).
The timeline to make completeness determinations in the version of
subpart Ba the EPA promulgated in 2019 mirrored the language for SIPs
in CAA section 110(k)(1)(B): ``Within 60 days of the Administrator's
receipt of a plan or plan revision, but no later than 6 months after
the date, if any, by which a State is required to submit the plan or
revision, the Administrator shall determine whether the minimum
criteria [for completeness] have been met.'' Like CAA section
110(k)(1)(B), subpart Ba also provided that a state plan would be
deemed complete by operation of law if the EPA had not made an
affirmative determination by the date 6 months after receipt of the
plan submission. 40 CFR 60.27a(g)(1).
    After a state plan is deemed complete through either an affirmative
determination or by operation of law, the EPA will act on the state
plan submission through notice-and-comment rulemaking. The timeline for
the EPA to act on a state plan submission runs from the date a
submission is deemed complete; more on this timeline can be found in
section III.A.3. of this preamble.
    If a state plan submission does not contain the elements required
by the completeness criteria, the EPA would find that the state has
failed to submit a complete plan and notify the state through a letter.
The determination of incompleteness treats the state as if the state
has made no submission at all. The determination that a submission is
incomplete and that the state has failed to submit a plan is
ministerial in nature.
    As part of the EPA's overall effort to set implementation timelines
under CAA section 111(d) that are as expeditious as possible, the EPA
proposed to revise the timing element of the completeness review at 40
CFR 60.27a(g)(1). In light of the ministerial nature of the
completeness determination, the EPA proposed a maximum of 60 days from
receipt of the state plan submission for the EPA to make a
determination of completeness. The EPA additionally proposed that any
state plan or plan revision submitted to the EPA that has not received
a completeness determination within 60 days of receipt, shall on that
date be deemed, by operation of law, to meet the completeness criteria,
which will trigger the EPA's obligation to take substantive action on
the state plan. Sixty days provides an expeditious timeframe for the
EPA to evaluate state plans for completeness and to notify the states
of the determination. Because the EPA may be required to evaluate up to
50 state plans during this period, in addition to plans submitted by
territories and tribes, the EPA explained at proposal that it did not
find that this timeframe could reasonably be shortened any further.
    While most commenters supported the 60-day completeness period,
some commenters expressed concern that a state plan that is
automatically deemed complete by operation of law as of the allotted 60
days could cause unnecessary turbulence in state plan implementation if
the plan is later disapproved by the EPA due to missing information.
Other commenters noted that if a plan is determined to be incomplete, a
60-day period will not allow states sufficient time to correct the
deficiency and submit a complete plan. First, the EPA notes that the
completeness determination is ministerial in nature and does not affect
the Agency's subsequent responsibility and authority to substantively
review a state plan submission against the requirements of the Act and
applicable regulations, including this subpart Ba and the relevant EG.
That is, a determination that a state plan is complete does not signify
that it necessarily satisfies the substantive requirements. The
commenters fail to explain how deeming a state plan submission complete
by operation of law, in this case after 60 days, and later finding it
does not satisfy an applicable requirement is a new phenomenon or would
cause unnecessary turbulence in state plan implementation. Rather, a
shorter period for deeming plans complete by operation of law would be
less disruptive than a longer period in this instance because the EPA
will complete its substantive evaluation of the plan sooner and the
state will have notice earlier on of any deficiencies. Additionally,
because states may submit plan revisions at any time, states may

work collaboratively with the EPA on any portions of a plan identified
as being deficient during both the completeness determination period
and the period for the EPA's substantive review of the plan. Thus,
again, a shorter completeness determination period that includes a
cutoff for deeming submissions complete by operation of law merely
keeps the state plan review process moving expeditiously and does not
foreclose any state opportunities to correct or supplement submissions
at any point in the EPA's review process.
    Moreover, the EPA intends to review for completeness as soon as
possible after submittal. Although the EPA believes that it will be
able to provide a timely completeness determination for most if not all
state plan submissions, providing for completeness through operation of
the law will help ensure that the EPA's action on state plans does not
significantly delay plan processing or implementation.
    The EPA is therefore finalizing the completeness provision at 40
CFR 60.27a(g)(1) as proposed. The EPA notes that if the EPA determines
a plan is incomplete, the EPA is required to promulgate, through
notice-and-comment rulemaking, a Federal plan. See sections III.A.4.
and III.B. for the discussion and final amendments associated with the
timeline and triggers of the Federal Plan respectively. If a state
submits a plan prior to the state plan submission deadline and the EPA
also makes a determination that the plan is incomplete prior to that
deadline, the EPA will treat the state as if the state has made no
submission at all, but this determination does not yet trigger further
action by the EPA. Instead, because the state still has an opportunity
to submit a complete plan before the state plan submission deadline,
the EPA's authority to promulgate a Federal plan is only triggered if
the state fails to timely submit a new plan to replace the incomplete
plan by the state plan deadline.
3. Timeline for the EPA's Action on State Plans
    After a state plan has been determined to be complete or is deemed
complete by operation of law, CAA section 111(d) provides that the EPA
must evaluate whether the plan is ``satisfactory''; that is, whether
the components of the plan meet all the requirements of the statute,
these implementing regulations, and the corresponding EG. The EPA does
so by evaluating a plan (or plan revision) to determine whether the
plan or plan revision is approvable, in part or in whole (see section
III.D.1. of this preamble for discussion on partial plan approvals),
through a notice-and-comment rulemaking process. After the EPA proposes
an action on a state plan submission (e.g., approval, partial approval/
partial disapproval, disapproval) and reviews comments on the proposed
action, the EPA will finalize its action on the plan. If the EPA
approves a state plan, the standards of performance and other
components of that state plan become federally enforceable. If the
state plan is disapproved, in part or in whole, the EPA is obligated to
promulgate a Federal plan for designated facilities within the state
that were covered by the disapproved portions of the plan (see section
III.A.4. of this preamble below for the EPA's timeline to publish a
Federal plan).
    Subpart B requires the EPA to take action on applicable state plans
(e.g., approve or disapprove) within 4 months after the date required
for submission. 40 CFR 60.27(b). In the development of subpart Ba, the
EPA contended that 4 months was an inadequate time to review and take
action on state plans and therefore instead provided a deadline of 12
months for final action on a state plan (mirroring the maximum time
permitted under CAA section 110(k)(1)(2) for the EPA's action on
complete SIPs). 84 FR 32520, July 8, 2019. In the ALA decision, the
D.C. Circuit vacated this revised timeline in subpart Ba on the basis
that the EPA did not adequately justify the extended timeframes and did
not consider the public health and welfare impacts of extending the
implementation times. As is discussed below, the EPA has in this
rulemaking closely evaluated the process, steps, and timeframes for the
EPA to substantively review and act upon each state plan submission
through a public notice-and-comment rulemaking process. After
considering the time anticipated to be necessary for generally
expeditious EPA action on state plans, the EPA again proposed that it
must take final action on a state plan or plan revision submission
within 12 months after a plan is determined to be complete or becomes
complete by operation of law.\26\
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    \26\ The deadlines for the EPA action under subpart Ba would
apply to any state plan submission regardless of when it is
submitted.
---------------------------------------------------------------------------

    In the notice of proposed rulemaking, the EPA explained that the
first step it takes once a state plan submittal has been deemed
``complete'' under 40 CFR 60.27a(g) is for an intra-agency workgroup to
review the plan components to determine whether they conform to the
applicable regulatory requirements. The workgroup may require a broad
range of expertise in legal, technical, and policy areas, potentially
including attorneys, engineers, scientists, economists, air monitoring
experts, health and welfare analysts, and/or policy analysts from
across a variety of the EPA programs. After review and coordination,
the workgroup then develops recommendations for approval or disapproval
of each plan component and presents them to Agency decision-makers for
review. Once the Agency completes its internal decision-making process,
the workgroup proceeds to prepare a written notice of proposed
rulemaking. The notice of proposed rulemaking contains the EPA's legal,
policy, and technical bases for its proposed action on a state plan
submission, which must be thoroughly developed and explained in writing
to provide clear and concise information and reasoning to support the
public in understanding the Agency's decision and the justification for
that decision, and so that the public may provide informed comments on
the proposal. The EPA may further develop technical support documents
as record support for the proposal. The draft proposed rulemaking and
any record support then undergo a multi-layered review process across
the EPA offices and levels of management before being processed for
signature. The process to evaluate the state plan, draft a proposed
action on a CAA section 111(d) state plan, and get the proposed action
edited, reviewed, and signed typically requires a minimum of between 6
to 8 months to complete. The signed notice of proposed rulemaking is
then submitted for publication in the Federal Register, which may
require several weeks of review and processing prior to publication.
    The publication of the proposed rulemaking triggers the start of a
public comment period of at least 30 days with possible extension, if
requested by commenters. Because of the types of sources and pollutants
regulated under CAA section 111(d), the EPA reasonably anticipates that
many of its proposed actions on state plans will garner significant
public interest from individuals, industry, states, and environmental
and public health advocates. After completion of the comment period,
the EPA then reviews all comments and determines whether, based on any
information provided by the comments, it should alter its proposed
action or further augment the legal, policy, and technical rationales

supporting that action. Comments received on a proposed action may
include technical information that was not available to the EPA at the
time of proposal. In the event technical data are received as part of
comments on the proposed action, the EPA would then be required to
review the new data and evaluate whether and how it should affect the
EPA's proposed conclusions regarding the state plan. If a substantive
comment is raised that merits reconsideration of the EPA's proposed
action, the EPA may determine that it is necessary to revise and
repropose its action on the state plan or it may go to the state for
more information to help the Agency determine how to proceed.
    Once this review of comments is complete, the workgroup drafts and
presents updated recommendations for action for internal review and
consideration by Agency decision-makers. Once the Agency completes its
internal decision-making process, the workgroup then drafts a notice of
final rulemaking on the plan submission, which includes responses to
comments, any necessary record support, and may also include final
regulatory text. The draft final action is then reviewed by senior
management and other interested EPA offices within the Agency prior to
signature of the final rulemaking approving or disapproving, in whole
or in part, a state plan. It is reasonable to permit at least 4 to 7
months for evaluation of the comments received, any necessary technical
analysis, decision-making, and drafting and review of the final action.
    The duration of each step in this deliberative process varies. The
amount of time the EPA needs to review a state plan submission and the
time it needs to finalize a notice of proposed rulemaking depends in
part on the plan's complexity and the nature of the technical, policy,
and legal issues that it implicates. For example, a state plan
submission that includes standards of performance for dozens of
facilities on different compliance schedules would be more complex and
time consuming to review than a plan that simply establishes standards
of performance reflecting the presumptive level of stringency for all
sources. Similarly, the amount of time needed to respond to comments
and issue a final rulemaking depends in part on the number and type of
comments received on the EPA's proposed rulemaking. Additionally, the
EPA reasonably anticipates that it will be required to review multiple
plan submissions at a given time, and these phases of review for a
given plan are impacted by the EPA's review of other state plan
submissions, as the EPA will need to assure its review across multiple
plans and regional offices is consistent from a legal, technical, and
policy perspective.
    While some commenters supported 12 months as an expeditious
timeframe for the EPA review and action on state plan submittals,
several noted that 12 months may be insufficient. These commenters
asserted that the EPA must meaningfully evaluate and take action on a
state plan and a 12-month timeframe may be too short for this process.
However, as detailed in the discussion above, the EPA has a mapped out
the time necessary to take action on a generic plan submission and
believes that 12 months is the most expeditious and therefore the most
appropriate period to provide for these generally applicable
implementing regulations. Additionally, the EPA has completed hundreds
of actions on CAA section 110 SIPs within 12 months over the past 4
years. Given that the EPA may choose to supersede the requirements of
subpart Ba as necessary in an individual EG, we believe that providing
the shortest period here is consistent with considering health and
welfare impacts by designing timelines to achieve state plan
implementation as expeditiously as reasonably possible.
    The EPA is therefore finalizing as proposed 40 CFR 60.23a(b) to
provide that it will take action on a state plan or plan revision
within 12 months of a determination of a complete plan pursuant to 40
CFR 60.27a(g). This is a reasonably expeditious timeframe to
accommodate the EPA action on a state plan or plan revision submission
and the considerations described above, while ensuring that an EG is
expeditiously implemented. The process and steps described in this
action highlight the fact that it would be unreasonable, if not
impossible, to accomplish all of the steps in a legally and technically
sound manner within a 4-month timeframe as required under subpart B.
Particularly, any proposed action by the EPA has to be open for public
comment for at least 30 days, and therefore the 4-month timeline
provided in subpart B only gave the EPA 3 months to do the substantive
work of both the proposed and final actions, including evaluating the
state plan submission, drafting preamble notices, responding to
comments, and developing record support at both the proposed and final
action stages. A 12-month timeframe after a plan is determined to be
complete more reasonably accommodates the process and steps described
in this action.\27\
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    \27\ While the EPA would have the discretion to act on a state's
submission more quickly than 12 months where specific circumstances
allow (e.g., where there are no public comments on the proposed
action), the EPA does not believe that it would be reasonably
possible to act significantly more quickly than 12 months in most
cases.
---------------------------------------------------------------------------

    As explained at proposal, the EPA recognizes that the court in ALA
faulted the Agency for failing to consider the potential impacts to
public health and welfare associated with extending planning deadlines.
The EPA does not interpret the court's direction to require a
quantitative measure of impact, but rather consideration of the
importance of the public health and welfare goals of CAA section 111(d)
when determining appropriate deadlines. Because 12 months is an
adequate period of time in which the EPA can both expeditiously act on
a plan submission and ensure that its action is technically and legally
sound, it follows that the EPA has appropriately considered the
potential impacts to public health and welfare associated with this
extension of time by providing no more time than the EPA reasonably
needs to ensure a plan submission contains appropriate and protective
emission reduction measures. If the EPA does not have adequate time to
evaluate a state plan submission, its ability to ensure the plan
contains appropriate measures to satisfactorily implement and enforce
the standards necessary to comply with the EG may be compromised, which
would in turn compromise the EPA's ability to ensure that the public
health and welfare objectives of the EG are satisfied. Although several
commenters noted that the review of some plans may require a more in
depth analysis, the EPA believes 12 months is a both reasonable and
expeditious timeframe to evaluate and act on most state plans.
Accordingly, in order to ensure that the public health and welfare
objectives of CAA section 111 are timely realized, and consistent with
the direction in ALA, the EPA does not believe it would be appropriate
to finalize a timeframe longer than 12 months for the EPA action on
state plans.
4. Timeline for the EPA To Promulgate a Federal Plan
    CAA section 111(d)(2) provides that the EPA has the same authority
to prescribe a Federal plan for a state that fails to submit a
satisfactory plan as it does for promulgating a FIP under CAA section
110(c). Accordingly, the EPA's obligation to promulgate a Federal plan
is triggered in three situations: where a state does not submit a plan
by the plan

submission deadline; where the EPA determines a portion or all of a
state plan submission did not meet the completeness criteria and the
time period for state plan submission has elapsed and, therefore, the
state is treated as having not submitted a required plan; and where the
EPA disapproves a state's plan. 40 CFR 60.27a(c). The EPA is finalizing
as proposed the revisions to 40 CFR 60.27a(c) providing that the Agency
will promulgate a Federal plan at any time within 12 months of any of
the triggers in Sec.  60.27a(c)(1) and (2) (see section III.B. of this
preamble for discussion).\28\
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    \28\ The EPA has discretion to address its obligation to
promulgate a Federal plan in a variety of ways for states that do
not have an approved state plan. For example the EPA may initially
promulgate a single Federal plan that applies to all appropriate
states and then update that Federal plan as necessary to accommodate
the inclusion of other states that trigger the need for a Federal
plan in the future (e.g., a Federal plan that applies to states that
fail to submit a plan can be updated to include applicability for
states that later have a plan disapproved); or the EPA may
promulgate separate Federal plans each time its authority to do so
has been triggered (e.g., the EPA will promulgate a Federal plan for
all states that fail to submit a plan and another Federal plan for
all states that have their plan disapproved).
---------------------------------------------------------------------------

    The EPA is obligated to promulgate a Federal plan for states that
have not submitted a plan by the submission deadline. Once the
obligation to promulgate a Federal plan is triggered, it can only be
tolled by the EPA's approval of a state plan. If a Federal plan is
promulgated, a state may still submit a plan to replace the Federal
plan. A Federal plan under CAA section 111(d) is a means to ensure
timely implementation of EGs, and a state may choose to accept a
Federal plan for their sources rather than submit a state plan. While
the EPA encourages states to timely submit plans for EGs, there are no
sanctions associated with failing to timely submit an approvable plan
or with the implementation of a Federal plan.\29\
---------------------------------------------------------------------------

    \29\ CAA section 179 provides that sanctions should be applied
in states that fail to submit approvable SIPs for certain specified
requirements for NAAQS implementation. The EPA has not promulgated
any similar sanctions provisions governing the submission of state
plans pursuant to section 111(d).
---------------------------------------------------------------------------

    The original implementing regulations in subpart B provided the EPA
with 6 months to promulgate a Federal plan once its obligation to do so
was triggered. 40 CFR 60.27(d). When the EPA promulgated subpart Ba in
2019, it concluded that this amount of time was insufficient and
consequently extended the time for the EPA to promulgate a Federal plan
to 24 months, mirroring the timeframe permitted for promulgation of a
FIP under CAA section 110. 84 FR 32520, July 8, 2019. In the ALA
decision, the D.C. Circuit vacated this revised timeline in subpart Ba
on the basis that the EPA did not adequately justify the extended
timeframe and did not consider the health and welfare impacts of
extending the implementation timeframe.
    At proposal, the EPA reevaluated the process, steps, and timeframes
for the EPA to promulgate a Federal plan through a public notice-and-
comment rulemaking process and proposed a 12-month timeframe to
promulgate a Federal plan once its obligation to do so is
triggered.\30\ As explained in the notice of proposed rulemaking, a
Federal plan must meet the requirements of CAA section 111(d) and
therefore contain the same components as a state plan, namely standards
of performance for designated facilities and measures that provide for
the implementation and enforcement of such standards. CAA section
111(d)(2)(B) also explicitly requires the EPA to consider RULOF in
promulgating a standard of performance under a Federal plan.
Additionally, Federal plans containing standards of performance are
subject to the procedural requirements of CAA section 307(d), such as
the requirements for proposed rulemaking and opportunity for public
hearing. CAA section 307(d)(1)(C). The EPA's regulations at 40 CFR
60.27a implement these various statutory requirements and contain
general regulatory requirements for the EPA's promulgation of a Federal
plan. The process, and steps for the EPA to promulgate a Federal plan
consistent with these applicable requirements is described in the
following paragraphs.
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    \30\ The EPA reviewed the information available in 40 CFR part
62 associated with the promulgation of Federal Plans under CAA
section 111(d). The supporting information reviewed is available at
Docket ID No. EPA-HQ-OAR-2021-0527. Under the provisions of CAA
section 111 and subpart B, the EPA promulgated Federal plans for
municipal solid waste landfills EG 40 CFR part 60, subpart Cc
(Federal plan codified at 40 CFR part 62, subpart GGG) and municipal
solid waste landfills EG 40 CFR part 60, subpart Cf (Federal plan
codified at 40 CFR part 62, subpart OOO).
    The EPA also reviewed information available in 40 CFR part 62
associated with the promulgation of Federal Plans under CAA 129. The
supporting information reviewed is available at Docket ID No. EPA-
HQ-OAR-2021-0527. Under the provisions of CAA sections 111 and 129
and subpart B, the EPA has promulgated Federal plans for large
municipal waste combustors EG 40 CFR part 60, subpart Cb (Federal
plan codified at 40 CFR part 62, subpart FFF); small municipal waste
combustors EG 40 CFR part 60, subpart BBBB (Federal plan codified at
40 CFR part 62, subpart JJJ); hospital, medical, and infectious
waste incinerators EG 40 CFR part 60, subpart Ce (Federal plan
codified at 40 CFR part 62, subpart HHH); commercial and industrial
solid waste incinerators EG 40 CFR part 60, subpart DDDD (Federal
plan codified at 40 CFR part 62, subpart III) and sewage sludge
incinerators EG 40 CFR part 60, subpart MMMM (Federal plan codified
at 40 CFR part 62, subpart LLL).
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    Once the EPA's obligation to promulgate a Federal plan is
triggered, the EPA establishes an intra-agency workgroup to develop the
rulemaking action to address that obligation. The workgroup first
develops recommendations for the components of the Federal plan to be
proposed, and on legal, policy, and technical rationales that support
the recommendations. These components are identified in subpart Ba as
well as in the corresponding EG and are generally the same as those
required for a state plan. One of these fundamental components is the
determination of standards of performance for designated facilities.
Based on the requirements of CAA sections 111(d) and 111(a)(1), these
standards must generally reflect the degree of emission limitation
achievable through application of the BSER as determined by the EPA as
part of the EG. Depending on the form of the BSER and the degree of
emission limitation in a particular EG, the EPA may need to do
additional work to calculate standards of performance that reflect this
level of stringency. For example, an EG may translate the degree of
emission limitation into a presumptive standard in the form of
numerical emission rates, which a Federal plan could simply adopt as
the requisite standards of performance. However, if an EG provides the
degree of emission limitation in a form other than presumptive
numerical standards, and the EPA may need to calculate appropriate
standards of performance in the context of a Federal plan. Further, CAA
section 111(d)(2) requires the EPA to consider RULOF for sources in the
source category in setting standards of performance as part of a
Federal plan which requires the EPA to identify whether the remaining
useful lives of relevant designated facilities, among other appropriate
factors, merit the EPA establishing different standards of performance
for those facilities. The development of a Federal plan may also
necessitate that the EPA determine appropriate testing, monitoring,
reporting, and recordkeeping requirements to implement the standard if
the EG does not provide presumptive requirements to address those
aspects of implementation. Further, the EPA will need to consider
associated compliance times for designated facilities in circumstances
where they are not provided by an EG, or in cases where a standard of
performance is adjusted to account for RULOF. There may also be
situations where IoPs are warranted,

and the EPA will correspondingly need to identify and determine the
appropriate IoPs. The development of a Federal plan with these
components, or of significant revision to a Federal plan, will also
include elements of meaningful engagement, as finalized in this action
including revision to section 40 CFR 60.29a and as further described in
section III.C. of this preamble.
    Once the recommendations for each component are developed, the
workgroup presents them to Agency decision-makers for review. After the
Agency completes its internal decision-making process, the workgroup
proceeds to prepare a written notice of proposed rulemaking. The
proposal must include the following elements, as required by CAA
section 307(d)(3): the factual data on which the proposed rulemaking is
based; the methodology used in obtaining the data and in analyzing the
data; and the major legal interpretations and policy considerations
underlying the proposed rulemaking. These elements must be thoroughly
developed and explained in the proposal to meaningfully provide the
public adequate information to comment on the proposal. The EPA may
further develop a technical support document as record support for the
proposal.
    The draft proposed rulemaking and any record support are then
reviewed by the relevant EPA offices and processed for signature. The
signed notice of proposed rulemaking is then submitted for publication
in the Federal Register. To develop the proposed Federal plan
rulemaking, establish unique standards for RULOF, allow review of
materials by senior management, go through an interagency review
process and have the package signed typically requires a minimum of
between six to nine months to complete.
    As previously noted, the EPA's promulgation of a Federal plan is
subject to the requirements of CAA section 307(d), which includes
providing the public with an opportunity to provide an oral
presentation at a public hearing. CAA section 307(d)(5). The Federal
Register Act requires the EPA to provide sufficient notice of a public
hearing, which (in the absence of a different time specifically
prescribed by the relevant Act of Congress) is satisfied if the EPA
provides at least 15 days' notice. 44 U.S.C. 1508. Section 307(d)(5) of
the CAA further provides that the EPA must keep the record for the
proposed action open for public comment for 30 days after any public
hearing for the submission of rebuttal and supplemental information.
Because the EPA reasonably expects to provide notice of the required
public hearing at the time its proposed action is published in the
Federal Register, in order to allow for both a 15-day notice of the
public hearing and a subsequent 30-day comment period on the open
record, the EPA should allow for at least 45 days for public comment on
the notice of proposed action.
    As with state plans, because of the types of sources and pollutants
regulated under CAA section 111(d), the EPA reasonably anticipates that
many of its proposed actions on a Federal plan will garner significant
public interest from individuals, industry, states, and environmental
and public health advocates. After completion of the comment period,
the EPA then reviews all comments and determines whether, based on any
comment, it should alter any components of the proposed Federal plan,
or further augment the legal, policy, and technical rationales
supporting that proposed action. Additionally, in the EPA's experience,
comments may include technical information that was not in front of the
Agency at the time of proposal. In the event technical data are
received as part of comments on the proposed action, the EPA would then
be required to review the new data and evaluate whether and how it
should affect the EPA's proposed Federal plan. If a substantive comment
is raised that merits reconsideration of any component in the proposed
Federal plan, the EPA would need to repropose the plan.
    Once this review of comments is complete, the workgroup drafts and
presents updated recommendations for internal review and decision
making. Once the Agency completes its internal decision-making process,
the workgroup then drafts a notice of final rulemaking, which includes
responses to comments and any necessary record support, and final
regulatory text as the Federal plan directly regulates certain
designated facilities. The draft final action is then reviewed by
relevant offices within the Agency prior to signature of the final rule
promulgating the Federal plan. The EPA typically anticipates that the
process of reviewing comments received, making corresponding changes to
the rulemaking, and promulgating the final Federal plan to be between 4
and 8 months.
    The duration of each step in this deliberative process varies. The
amount of time the EPA needs to develop, propose, and finalize a
Federal plan depends in part of the plan's complexity and the nature of
the technical, policy, and legal issues that it implicates. For
example, some states needing a Federal plan may have thousands, if not
hundreds of thousands, of designated facilities for which the EPA will
need to establish standards of performance and implementation measures,
while other Federal plans may be significantly smaller in scale.
Similarly, the amount of time needed to respond to comments and issue a
final rule depends in part on the number and type of comments received
on the EPA's proposed rulemaking. Additionally, the EPA reasonably
anticipates that it may need to promulgate a Federal plan for multiple
states at a given time, which can amplify the amount of time and work
needed.
    In response to this proposed timeline, several commenters asserted
that the EPA should provide itself more than the proposed 12 months to
promulgate a Federal plan, with some commenters noting additional time
needed for the EPA to provide for meaningful engagement and
consideration of RULOF. However, based on the assessment as presented
in the preceding paragraphs, recognizing that much of the evaluation
needed for promulgating a Federal plan will be performed by the EPA
during development of the EG, considering the need for expeditious
implementation of EGs, and noting that RULOF is expected to only be
needed for certain limited circumstances, the EPA is finalizing the
requirement that it promulgate a Federal plan within 12 months once its
obligation to do so is triggered, i.e., either the date required for
submission of a state plan (for states that fail to submit a complete
plan) or the date the EPA disapproves a state's plan. As with the other
timelines in subpart Ba, the EPA may supersede the 12 month timeline
for a Federal plan as appropriate depending on the circumstances of the
applicable EG.
    The EPA also recognizes that some commenters stated that the EPA
need not and should not wait for its Federal plan obligation to be
``triggered'' to begin developing such a plan. The EPA agrees that
early development of the Federal plan, where possible before the EPA's
obligation is formally triggered, could provide the EPA with additional
time to meet this deadline. The EPA notes that to further streamline
the timeline associated to the issuance of a Federal plan, the EPA is
also finalizing the proposed change to the trigger for the EPA's
obligation and timeline to provide a Federal plan for states that do
not submit a timely plan. That discussion is found in section III.B. of
this preamble.

    Thus, the EPA is finalizing as proposed the revisions to 40 CFR
60.27a(c) providing that the Agency will promulgate a Federal plan at
any time within 12 months of any of the triggers in Sec.  60.27a(c)(1)
and (2). While retaining the authority to supersede this timeline in an
EG if appropriate, the EPA has determined that 12 months reasonably
accommodates the amount of time that the EPA needs to undertake the
process, steps, and the considerations described above, while ensuring
that an EG is expeditiously implemented. The process and steps
described earlier that the EPA must be taken in promulgating a Federal
plan highlight the fact that it would be unreasonable, if not an
impossibility, to accomplish all of the steps in a legally and
technically sound manner within a 6-month timeframe as required under
subpart B.\31\
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    \31\ While the EPA would have the discretion to promulgate a
Federal plan more quickly than 12 months where specific
circumstances allow (e.g., where there are no public comments on the
proposed action), the EPA does not believe that would be reasonably
possible to act significantly more quickly than 12 months in most
cases.
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    As with the EPA's finalized timeline to act on state plan
submissions, 12 months is generally the period of time in which the EPA
can both expeditiously complete a Federal plan and ensure it is
technically and legally sound. Therefore, this time period considers
potential impacts to public health and welfare by giving the EPA a
reasonably expeditious timeframe to promulgate a Federal plan that
contains appropriate and protective emission reduction measures. This
is especially true in the context of a Federal plan, where there is
otherwise no state plan in place that is adequately protective of
public health and welfare. If the EPA does not have adequate time to
promulgate a Federal plan, its ability to ensure the plan contains
appropriate measures to satisfactorily implement and enforce the
standards necessary to comply with the EG may be compromised, which
would in turn compromise the EPA's ability to ensure that the public
health and welfare objectives of the EG are satisfied.
    The EPA notes that a state may submit a plan to replace a Federal
plan, even after the state plan submission deadline. However, once the
EPA's authority and obligation to promulgate a Federal plan has been
triggered, the act of a state submitting a plan alone does not abrogate
the EPA's authority or obligatory timeline to promulgate a Federal
plan. Only an approved state plan can supplant an already promulgated
Federal plan or abrogate the EPA's responsibility to timely promulgate
a Federal plan. Where a state submits a late plan, that may have the
practical effect of concurrent timelines for promulgation of the
Federal plan and the EPA's action on that late state plan; the EPA is
not obligated to act on a late state plan prior to promulgating a
Federal plan (40 CFR 60.27a(d)).
5. Timeline for Increments of Progress (IoPs)
    As part of the EPA's statutory responsibility to determine the
degree of emission limitation achievable through application of the
BSER and to include it in an EG, the EPA also determines in an EG ``the
time within which compliance with standards of performance can be
achieved.'' 40 CFR 60.22a(b)(5). Accordingly, state plans must include
both standards of performance for designated facilities and compliance
schedules for achieving those standards of performance.\32\
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    \32\ ``Each plan shall include standards of performance and
compliance schedules.'' 40 CFR 60.24a(a).
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    In 1975, the EPA defined in subpart B ``compliance schedule'' as
``a legally enforceable schedule specifying a date or dates by which a
source or category of sources must comply with specific standards of
performance contained in a plan or with any increments of progress to
achieve such compliance.'' In subpart B the EPA also defined
``increments of progress'' as steps to achieve compliance which must be
taken by an owner or operator of a designated facility including: (1)
submittal of a final control plan for the designated facility to the
appropriate air pollution control agency; (2) awarding of contracts for
emission control systems or for process modifications, or issuance of
orders for the purchase of component parts to accomplish emission
control or process modification; (3) initiation of on-site construction
or installation of emission control equipment or process change; (4)
completion of on-site construction or installation of emission control
equipment or process change; and (5) final compliance. The EPA adopted
these definitions without change when it promulgated subpart Ba in
2019.
    Subpart B requires that each state plan include emission standards
and compliance schedules. 40 CFR 60.24a. In addition, subpart B
specifies in 40 CFR 60.24(e)(1) that any compliance schedule extending
more than 12 months from the date required for submittal of the plan
must include legally enforceable increments of progress to achieve
compliance for each designated facility or category of facilities.
Unless otherwise specified in the applicable subpart, increments of
progress must include, where practicable, each increment of progress
specified in Sec.  60.21(h) and must include such additional increments
of progress as may be necessary to permit close and effective
supervision of progress toward final compliance. The provision in 40
CFR 60.24(e)(1) was amended in 2000.\33\ The 2000 amendments to 40 CFR
60.24(e)(1) added the words ``Unless otherwise specified in the
applicable subpart'' to the requirements associated with IoPs. The EPA
described in the 1999 proposal that the purpose of this amendment was
to allow the EPA, in a specific subpart, discretion in the number of
IoPs that a designated facility must meet. Without this amendment
subpart B required designated facilities to meet all five IoPs
specified in the IoP definition. In the 1999 proposal the EPA
recognized that while for some categories of designated facilities the
five increments are appropriate, all five IoPs may not be necessary to
ensure compliance for other categories of designated facilities.
Therefore, EPA proposed and finalized amendments to 40 CFR 60.24(e) to
allow discretion and flexibility in establishing IoPs for a particular
subpart.
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    \33\ 65 FR 76380 (Dec 6, 2000).
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    In promulgating subpart Ba in 2019, the EPA largely carried over
the requirement of subpart B at 40 CFR 60.24(e)(1) in a new provision
40 CFR 60.24a(d).\34\ However, to align the trigger of IoPs in 40 CFR
60.24a(d) to the updated timelines it was finalizing in subpart Ba, in
2019 the EPA adopted a timeframe trigger for IoPs of 24-months instead