[Federal Register Volume 86, Number 135 (Monday, July 19, 2021)]
[Rules and Regulations]
[Pages 37918-37935]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-13905]


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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 51 and 52

[EPA-HQ-OAR-2019-0435; FRL-10017-29-OAR]
RIN 2060-AU46


New Source Review Regulations; Correction

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule; correction.

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

SUMMARY: The Environmental Protection Agency (EPA) is amending several 
New Source Review (NSR) regulations by making the following types of 
changes: Correcting typographical and grammatical errors, removing 
court vacated rule language, removing or updating outdated or incorrect 
cross references, conforming certain provisions to changes contained in 
the 1990 Clean Air Act (CAA or Act) Amendments, and removing certain 
outdated grandfathering or transitional exemptions.

DATES: This final rule is effective on August 18, 2021.

ADDRESSES: The EPA has established a docket for this action, identified 
by Docket ID No. EPA-HQ-OAR-2019-0435. All documents in the docket are 
listed in the http://www.regulations.gov website. Although listed in 
the index, 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 either electronically in the docket or in hard 
copy at the EPA Docket Center Reading Room, WJC West Building, Room 
3334, 1301 Constitution Avenue NW, Washington, DC 20004. Out of an 
abundance of caution for members of the public and our staff, the EPA 
Docket Center and Reading Room are closed to the public, with limited 
exceptions, to reduce the risk of transmitting COVID-19. Our Docket 
Center staff will continue to provide remote customer service via 
email, phone, and webform. For further information on EPA Docket Center 
services and the current status, please visit us online at https://www.epa.gov/dockets. The hours of operation at the EPA Docket Center 
Reading Room are 8:30 a.m.-4:30 p.m., Monday-Friday. The telephone 
number for the EPA Docket Center is (202) 566-1744.

FOR FURTHER INFORMATION CONTACT: For general questions about this 
document, please contact Mr. Ben Garwood, New Source Review Group, Air 
Quality Policy Division, Office of Air Quality Planning and Standards 
(C504-03), Environmental Protection Agency, Research Triangle Park, 
North Carolina, 27711; telephone number (919) 541-1358; fax number 
(919) 541-4028; email address: [email protected].

SUPPLEMENTARY INFORMATION: Throughout this document wherever ``we,'' 
``us,'' or ``our'' is used, we mean the EPA.

Table of Contents

I. Background
II. Response to Comments
III. Final Action
IV. Removal of Vacated Ozone NAAQS Grandfathering and Ozone 
Interprecursor Trading Provisions
V. Environmental Justice Considerations
VI. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and 
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Paperwork Reduction Act (PRA)
    C. Regulatory Flexibility Act (RFA)
    D. Unfunded Mandates Reform Act (UMRA)
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From 
Environmental Health and Safety Risks
    H. Executive Order 13211: Actions That Significantly Affect 
Energy Supply, Distribution, or Use
    I. National Technology Transfer and Advancement Act (NTTA)
    J. Executive Order 12898: Federal Actions To Address 
Environmental Justice in Minority Populations and Low-Income 
Populations
    K. Congressional Review Act (CRA)
    L. Judicial Review
VII. Statutory Authority

I. Background

    The EPA published a notice of proposed rulemaking (NPRM) on 
December 20, 2019 (``2019 NPRM'' or ``2019 proposal'') \1\ including 
revisions to four sets of NSR regulations.\2\ The proposed revisions 
were intended to correct various typographical and grammatical errors, 
remove regulatory provisions that have been vacated by the court, 
remove or update outdated or incorrect cross references, conform 
certain provisions to changes contained in the 1990 CAA Amendments, and 
remove outdated exemptions.
---------------------------------------------------------------------------

    \1\ 84 FR 70092 (December 20, 2019).
    \2\ The four sets of NSR regulations include the Prevention of 
Significant Deterioration regulations at 40 CFR 51.166 and 52.21, 
and the Nonattainment NSR regulations at 40 CFR 51.165 and part 51 
Appendix S (also known as the Emission Offset Interpretative 
Ruling).
---------------------------------------------------------------------------

    The NSR regulations have undergone revisions and restructurings by 
the EPA during their long history as a result of statutory and policy 
changes, as well as numerous court decisions. These revisions and 
restructurings have sometimes introduced errors within those 
regulations. In this action, the EPA is finalizing revisions to address 
these inadvertent errors. The agency is also finalizing other revisions 
to reflect statutory changes enacted by Congress which have already 
been applied in practice or changes that have been necessitated by 
court decisions. Thus, the EPA considers this final rule to be 
administrative in nature. The EPA's intent is to provide clarity to the 
affected NSR regulations, but not to alter the substantive requirements 
of those regulations. The NSR regulations affected by this action 
contain requirements for the preconstruction review of new major 
stationary sources and major modifications of existing major stationary 
sources.
    In response to the 2019 proposal, the EPA received 15 sets of 
comments: Five from industries and industry associations, five from 
anonymous commenters, four from state agencies, and one from an 
individual. The commenters generally agreed with most of the editorial 
and typographical changes that the EPA had proposed. Some commenters, 
however, disagreed with some of the proposed changes and made 
alternative recommendations for consideration in the final rule. In 
addition, some commenters identified additional regulatory text needing 
changes. The following section addresses some of the significant 
comments and provides the EPA's responses. For a complete description 
of the comments received and the EPA's responses, please refer to the 
Response to Comment (RTC) document that the EPA has placed in the 
docket for this rulemaking.
    In order to provide a clear description of the regulatory revisions 
contained in the 2019 proposal, the EPA also included a separate table 
in the rulemaking docket showing each of the

[[Page 37919]]

proposed changes in a redline/strikeout (RLSO) format to clearly 
illustrate where and what changes were proposed. Some commenters 
correctly noted that there were some inconsistencies between the 
changes shown in the docketed table and the revised regulatory text in 
the 2019 NPRM. These inconsistencies have been corrected in this final 
rule and the table has been revised to show all of the changes that are 
being made to the four sets of NSR regulations, including those that 
have been made since the 2019 proposal. Further, the EPA has made some 
very minor, non-substantive rule language format conforming revisions 
in this final rule as required by Office of the Federal Register (OFR) 
guidelines for rule language publication in the Federal Register 
according to the Document Drafting Handbook.\3\ These rule language 
consistency edits from OFR are contained in the final rule language and 
the revised table. The revised table is available in the docket for 
this final rule (see Reference Table of New Source Review Error 
Corrections--Final Rule, in Docket ID. No. EPA-HQ-OAR-2019-0435).
---------------------------------------------------------------------------

    \3\ See https://www.archives.gov/files/federal-register/write/handbook/ddh.pdf.
---------------------------------------------------------------------------

II. Response to Comments

    Based on the comments received, the EPA is not finalizing some of 
the proposed changes or is finalizing revised versions of the proposed 
changes. The following section provides a summary of many of the 
comments received and the EPA's response to those comments, including 
our rationale for not finalizing some of the proposed changes or 
modifying changes that were originally proposed. All of comments and 
responses, including those not discussed in this preamble, are included 
in the RTC, which the EPA has placed in the docket for this rulemaking.

Comments Received and the EPA's Responses

    A. Typographical, grammatical and punctuation errors. The EPA 
proposed to correct misspelled words, such as those contained in 40 CFR 
51.165(a)(1)(viii) and 51.166(j)(4). No adverse comments were received 
concerning these types of corrections. The EPA did, however, receive 
comments providing notification of similar typographical errors, 
including the incorrect use of the word ``and'' in lieu of ``through'' 
in 40 CFR 51.166(b)(48)(ii) and 52.21(b)(49)(ii), and is making these 
corrections along with similar proposed corrections such as the use of 
``that'' in lieu of ``than'' in 40 CFR 52.21(b)(1)(iii)(z). The EPA is 
also updating the rule language to correct other errors identified by 
commenters, including an inadvertent reference to ``Class II'' in the 
proposed revision to 40 CFR 52.21(u)(3), and other minor clarifying 
edits (see 40 CFR 51.165(a)(1)(xxi)(A) through (D), 51.165(a)(1)(xl), 
Appendix S II.A.12, Appendix S II.A.37, 51.166(b)(2)(iii)(a), 
51.166(b)(12), 51.166(b)(32)(i) through (iv), 51.166(b)(48)(ii), 
51.166(j)(1), 51.166(w)(9)(ii), 52.21(b)(12), 52.21(b)(33)(i) through 
(iv), 52.21(b)(49)(iii), and 52.21(j)(1)). These corrections are a 
logical outgrowth of the proposal but, in any event, the EPA also finds 
there is good cause to make these corrections without soliciting public 
comment on them because it would be unnecessary given that the changes 
are not substantive.\4\
---------------------------------------------------------------------------

    \4\ See 5 U.S.C. 553(b)(3)(B); 42 U.S.C. 7407(d)(1). For more 
information on the good cause exception to notice and comment 
rulemaking, see Section IV of this notice.
---------------------------------------------------------------------------

    In numerous instances, the EPA proposed to correct inappropriate 
words or punctuation, including capitalizations, commas and hyphens, 
such as those contained in 40 CFR 51.165(a)(2)(iii), Appendix S 
II.A.4.(iii), and 52.21(b)(23)(ii). One adverse comment was received on 
an edit proposed to the definition of ``emissions increase'' to change 
``is'' to ``shall be'' to make the language consistent throughout the 
paragraph. The EPA had only proposed this change in 40 CFR 52.21. The 
commenter pointed out that the use of ``is'' is already consistent 
within the paragraph and raised concern that the proposed change could 
be seen as suggesting that the provision would function as a 
significant emissions rate even though the EPA has not yet completed a 
rulemaking to set a significance level for GHGs. See 81 FR 68110 
(October 3, 2016). Instead the commenter suggested deleting a comma to 
clarify the provision. The EPA agrees with the commenter and is not 
changing ``is'' to ``shall be'' in 40 CFR 52.21(b)(49)(iii) and 
51.166(b)(48)(iii).
    Other errors identified by commenters or identified by the EPA 
subsequent to the 2019 proposal include the inadvertent capitalization 
of ``for'' in 40 CFR 52.21(b)(48)(i)(c) and the incorrect pluralization 
of the term ``standard'' in 40 CFR 51.166(j)(1). Correction of these 
errors is a logical outgrowth of the proposal but, in any event, the 
EPA also finds there is good cause to make these corrections without 
soliciting public comment because it would be unnecessary given that 
the changes are not substantive.
    B. Regulatory references. The EPA proposed to correct the way in 
which reference is made in one regulation to requirements contained in 
another regulation, such as references contained in 40 CFR 
51.165(a)(1)(v)(C)(5)(i), 51.166(b)(2)(iii)(e)(1), 
51.166(b)(2)(iii)(f), Appendix S II.A.5.(iii)(e)(1), and Appendix S 
II.A.5.(iii)(f). In some cases, the references were outdated, while 
others simply referenced an incorrect paragraph. The EPA did not 
receive adverse comment on these changes and the EPA is finalizing them 
in this rule. The EPA is also updating a reference made in 40 CFR 
51.165(a)(3)(ii)(D) in response to a comment requesting that a 
reference made within this regulation to a memorandum be updated to 
reflect the subsequent codification of the referenced language. The EPA 
is similarly amending a dated reference in 40 CFR 51 Appendix S I. 
Introduction and correcting an erroneous cross reference in Paragraph 
IV.D from V to IV in response to comments received. These corrections 
are a logical outgrowth of the proposal but, in any event, the EPA also 
finds there is good cause to make these corrections without soliciting 
public comment given that the changes are not substantive.
    C. Court vacaturs. Some of the proposed changes involve the removal 
of text that the EPA needed to remove to implement the vacatur of the 
provision in a court ruling. These changes include the following:
    1. In 2003, the U.S. Court of Appeals for the District of Columbia 
Circuit (D.C. Circuit) indefinitely stayed the effective date of the 
NSR provision known as the Equipment Replacement Provision (ERP), which 
amended the NSR requirements in 2003 to add a Routine Maintenance, 
Repair, and Replacement Exclusion.\5\ The ERP allowed sources to avoid 
NSR when replacing equipment under certain circumstances. The stay of 
the affected paragraphs was subsequently noted in the CFR under the 
three affected NSR regulations, 40 CFR 51.165, 51.166, 52.21.\6\ Later, 
in a 2006 decision, the court vacated the ERP, concluding that the 
provision was ``contrary to the plain language of section 111(a)(4) of 
the Act.'' New York v. EPA, 443 F.3d 880, 883 (D.C. Cir. 2006) (``New 
York II''). The EPA is now

[[Page 37920]]

removing the vacated ERP provisions consistent with New York II as well 
as the notes contained in the affected NSR regulations describing the 
indefinite stay of the various affected provisions. See proposed 40 CFR 
51.165(a)(1)(v)(C)(1), 51.165(h), 51.166(b)(2)(iii)(a), 51.166(y), 
52.21(b)(2)(iii)(a), and 52.21(cc).
---------------------------------------------------------------------------

    \5\ 68 FR 61248 (October 27, 2003).
    \6\ For example, in 40 CFR 52.21, the following note was added: 
``NOTE TO PARAGRAPH (b)(2)(III)(a): ``By court order on December 24, 
2003, the second sentence of this paragraph (b)(2)(iii)(a) is stayed 
indefinitely. The stayed provisions will become effective 
immediately if the court terminates the stay. At that time, EPA will 
publish a document in the Federal Register advising the public of 
the termination of the stay.''
---------------------------------------------------------------------------

    Additionally, in the proposal, the EPA noted that two components of 
the 2003 ERP rule, the criteria for ``basic design parameters'' 
(contained at 40 CFR 51.165(h)(2), 51.166(y)(2), and 52.21(cc)(2)), and 
``process units'' (contained at 40 CFR 51.165(a)(1)(xliii), 
51.166(b)(53), and 52.21(b)(55)), are incorporated within the 
definition of ``replacement unit,'' which was not part of the New York 
II decision. See 40 CFR 51.165(a)(1)(xxi), 51.166(b)(32), and 
52.21(b)(33). The EPA proposed to move definitions and criteria for 
``basic design parameters'' and ``process unit,'' into the definition 
of ``replacement unit'' in each of the three affected NSR regulations. 
See proposed 40 CFR 51.165(a)(1)(xxi)(E)-(F), 51.166(b)(32)(v)-(vi), 
and 52.21(b)(33)(v)-(vi).\7\ The EPA's 2019 proposal to move this 
language to a different location in the regulation necessitated 
revising a cross reference made to the definition of ``basic design 
parameters'' to cite its new location. See proposed 40 CFR 
51.165(a)(1)(xxi)(C), 51.166(b)(32)(iii), and 52.21(b)(33)(iii).\8\
---------------------------------------------------------------------------

    \7\ There is language related to ``process unit'' that is only 
relevant to the ERP and was therefore not proposed to be retained 
within the definition of ``replacement unit.''
    \8\ The EPA also notes that the ERP provisions and definition of 
``replacement unit'' (promulgated under a separate rulemaking not 
affected by the court's ERP vacatur) were not added to the NSR 
regulations at 40 CFR part 51 Appendix S when the EPA amended the 
other NSR regulations in 2003. To fix this omission of the 
replacement unit provision, the EPA proposed to add the definition 
of ``replacement unit,'' including the criteria for ``basic design 
parameters'' and ``process unit,'' to Appendix S. See proposed 
paragraph II.A.37. In addition, a provision explaining that a 
replacement unit is considered to be an existing emissions unit was 
proposed to be added to the definition of ``emissions unit.'' See 
proposed paragraph II.A.7.(ii). Together, these proposed changes 
were intended to make the Appendix S provisions concerning 
replacement units consistent with the other NSR regulations.
---------------------------------------------------------------------------

    Commenters had a variety of different recommendations in response 
to the EPA's 2019 proposal to relocate two definitions which the EPA 
did not consider to be subject to the court's vacatur decision. Those 
recommendations introduced alternative language for these provisions. 
Some commenters questioned the EPA's proposal to relocate certain 
components without also providing a more comprehensive rationale and 
opportunity for public comment. One commenter objected to moving the 
definition of ``process unit'' in an error corrections action, claiming 
that retaining provisions that were vacated by the court in a different 
location amounted to a substantive change because it ``represents 
neither a statutory change nor a change required by a court decision.'' 
The same commenter claimed that the EPA provided no rationale for why 
the vacated definition of ``process unit'' should be retained, and 
further stated that ``[i]f EPA believes a definition is necessary, it 
should provide an analysis of why the specific definition it has 
proposed is appropriate, instead of simply relying on a definition 
included in a rule that was vacated by a federal court.'' The commenter 
continued, however, that, should the EPA decide to define ``process 
unit'' as part of the definition of ``replacement unit,'' then ``[EPA] 
should clarify that this definition is limited to determining whether a 
unit meets the criteria for a replacement unit. This clarification 
would prevent confusion on the implication of this term.'' Finally, the 
commenter recommended, as an alternative, that the EPA ``could propose 
to eliminate the reference to process unit in the definition of 
`replacement unit' and instead reference an `emissions unit.' ''
    Three commenters recommended that the EPA retain the definition of 
``functionally equivalent component'' (e.g., 40 CFR 52.21(b)(56)), 
which the EPA proposed to remove as part of the ERP vacatur component 
of this rule. One of the commenters recommended that the EPA 
incorporate the definition of ``functionally equivalent component'' 
into the definition of ``replacement unit'' ``in order to retain the 
clarification that the `functionally equivalent component' definition 
provides.'' One of the commenters noted that ``[t]he replacement unit 
provision was intended to recognize that identical replacement is not 
required and often is not possible, which is why EPA will look to the 
`function' and the `basic design parameters.' '' This commenter 
concluded that ``[b]y deleting this definition, the intent of the 
replacement unit concept could be undermined.'' Finally, one of the 
commenters also recommended that the EPA retain the definition of 
``functionally equivalent component,'' as well as the definitions of 
``process unit'' and ``basic design parameters,'' as separate 
definitions rather than as part of the definition of ``replacement 
unit.''
    A state commenter did not agree with the EPA's 2019 proposal to 
relocate the three examples of ``process units'' for source categories, 
including refineries, municipal waste incinerators, and steam electric 
generating facilities. Another commenter recommended that if the EPA 
chose to retain an example of a process unit for a steam electric 
generating facility, the example should not include equipment that does 
not contribute to the production of electricity. The commenter claimed 
that ``EPA provides no explanation for the inconsistency between its 
example for a pulverized coal-fired facility and the proposed 
regulatory text for a steam electric generating facility, which states 
that only portions of the plant that contribute directly to the 
production of electricity would be included in the definition of 
`process unit.'''
    Another state agency commenter noted that in the 2019 proposal the 
EPA ``inadvertently'' left out the paragraph describing ``pollution 
control equipment,'' which the commenter stated was supposed to have 
been included in the definition of ``process unit'' and therefore 
should have been included with the EPA's proposal to relocate the 
definition of ``process unit.'' The affected provision, previously 
contained at 40 CFR 51.165(a)(1)(xliii)(B), 51.166(b)(53)(ii), and 
52.21(b)(55)(ii), reads as follows: ``Pollution control equipment is 
not part of the process unit, unless it serves a dual function as both 
process and control equipment. Administrative and warehousing 
facilities are not part of the process unit.''
    The EPA has carefully considered the adverse comments concerning 
the proposal to relocate certain provisions that were part of the 2003 
ERP rule vacated by the court in 2006. Due to the concerns expressed in 
the comments, the EPA has decided to also remove provisions pertaining 
to ``process unit'' and ``basic design parameters'' in this final rule. 
Based upon comments received, we have been persuaded that the better 
interpretation of the judgment in New York II is that the court vacated 
the ERP rule in its entirety, such that the EPA should remove all of 
this content to effectuate the judgment. While the replacement unit 
definition was adopted in a separate 2003 rulemaking that was not 
vacated by the court, that rulemaking action (which pre-dated New York 
II) does not provide a sufficient basis to conclude that content from 
the ERP rule that is referenced in definition of the ``replacement 
unit'' survived the vacatur. Since this dynamic is not addressed in New 
York II and that opinion post-dates the 2003 rule, the EPA believes New 
York II is best read as vacating all the content

[[Page 37921]]

adopted in the ERP rule. Therefore, at this time, the EPA is removing 
the entirety of the ERP rule from the NSR regulations and is not moving 
the definitions of ``basic design parameters'' and ``process unit'' 
into the ``replacement unit'' definition in this final rule. For the 
same reason, the EPA is removing the definition of ``functionally 
equivalent component'' as proposed.
    As a result of this action, the NSR regulations will lack a 
definition of ``basic design parameters'' and ``process unit'' that can 
be applied in the context of identifying whether a unit is a 
``replacement unit.'' However, while not controlling, the EPA and 
stakeholders may continue to look to the vacated definitions from the 
ERP rule to guide their understanding of the definition of 
``replacement unit.'' The EPA will evaluate whether further rulemaking 
is needed to restore definitions of ``basic design parameter'' and 
``process unit.'' If this need does arise, such a rulemaking would 
provide an opportunity for more targeted public input on the way such 
terms should be defined when applied in the specific context of 
defining a ``replacement unit'' for purposes of determining the method 
of calculating the change in emissions from a project. 2. In 2007, the 
EPA removed certain provisions pertaining to Clean Units (CU) and 
Pollution Control Projects (PCP), which were vacated by the D.C. 
Circuit in New York v. EPA, 413 F.3d 3 (D.C. Cir. 2005) (``New York 
I'').\9\ The EPA explained that, although the court's opinion addressed 
the CU and PCP provisions in 40 CFR 52.21, but not the corresponding 
provisions in 40 CFR 51.165 and 51.166, ``the plain language of the 
Court's opinion clearly applies to the parallel constructions in those 
latter provisions . . . .'' 72 FR 32526, 32527 (June 13, 2007). 
Accordingly, the EPA's 2007 action was intended to remove the relevant 
provisions from all three NSR regulations, but the EPA only specified 
its removal from 40 CFR 51.165 and not 40 CFR 51.166 and 52.21. 
Therefore, in the 2019 NPRM, the EPA proposed to remove the remaining 
CU and PCP provisions that were vacated in accordance with New York I. 
See proposed 40 CFR 51.166(b)(3)(iii)(c), 52.21(b)(3)(iii)(b), and 
cross references to vacated PCP provisions 40 CFR 51.165(a)(2)(ii)(A), 
51.166(a)(7)(iv)(a), and 52.21(a)(2)(iv)(a). The EPA did not receive 
any adverse comments addressing this aspect of the 2007 proposal and is 
therefore finalizing the changes to the regulatory text addressing the 
vacatur as proposed.
---------------------------------------------------------------------------

    \9\ 72 FR 32526 (June 13, 2007).
---------------------------------------------------------------------------

    D. Outdated and incorrect references.
    1. In 1980, the EPA made significant revisions to the PSD 
regulations under parts 51 and 52.\10\ One revision deleted existing 
paragraph (k) and redesignated paragraphs (l) through (s) as (k) 
through (r). The EPA proposed to correct incorrect references affected 
by the 1980 redesignation of paragraphs (l) through (s). The EPA 
received no adverse comment on this proposed revision and will be 
finalizing this change. See 40 CFR 51.166(r)(2) and 52.21(r)(4).
---------------------------------------------------------------------------

    \10\ 45 FR 52676 (August 7, 1980).
---------------------------------------------------------------------------

    2. In the same 1980 rulemaking, the EPA added a provision under the 
source obligation requirements at 40 CFR 52.21(r)(2) applicable to 
stationary sources that might be granted a future relaxation of a 
preconstruction permit that previously enabled the source or 
modification to be regulated as a ``minor'' rather than as a major 
stationary source. The provision requires the owner or operator of a 
source or modification obtaining a relaxation of the limits referenced 
to comply with the permit requirements for a major stationary source or 
major modification as if construction had not yet commenced on the 
source or modification. The provision references the permit 
requirements contained under paragraphs (j) through (s) of 40 CFR 
51.166. However, paragraph (s) contains discretionary provisions 
concerning the application of innovative control technology. In light 
of the non-mandatory nature of those provisions, it should not have 
been included in the reference to required permit elements. 
Accordingly, the EPA proposed to correct the source obligation 
requirement at 40 CFR 51.166(r)(2) by removing the reference to 
paragraph (s) and replacing it with a reference to paragraph (r). See 
proposed 40 CFR 51.166(r)(2). The EPA received a comment supporting 
this proposed change, but no adverse comments, and will therefore 
finalize this change as proposed.
    3. The Nonattainment New Source Review (NNSR) regulations at 40 CFR 
51.165 and 40 CFR part 51 Appendix S contain a restriction which 
prohibits sources that replace one hydrocarbon compound with another of 
lesser reactivity from obtaining emissions credit for that replacement. 
See 40 CFR 51.165(a)(3)(ii)(D) and part 51 Appendix S IV.C.4. At the 
same time, the provisions make it clear that a source may obtain an 
emissions credit, also referred to as an offset credit (when intended 
to be used as an emissions offset), in cases where a VOC is replaced by 
an organic compound that is not considered to be a VOC (i.e., 
recognized to have negligible photochemical reactivity). The EPA has 
now included as part of the regulatory definition of ``volatile organic 
compounds,'' codified at 40 CFR 51.100(s), organic compounds that are 
not VOCs that the EPA included in the definition because they have 
negligible photochemical reactivity. Accordingly, we proposed to revise 
both sets of NNSR regulations to provide an updated reference to the 
organic compounds that the EPA does not define as VOC.
    Two commenters recommended that the EPA completely delete, rather 
than edit, these provisions, asserting that they are outdated offset 
conditions. One of the commenters, using CAA section 173(c) as their 
basis, noted that ``[w]hen the EPA changed from regulating hydrocarbons 
to regulating VOC as a single pollutant, the EPA no longer considered 
reactivity in the offsets provision.''
    The EPA recognizes that because of the shift in how the EPA 
regulates photochemically reactive compounds that form ozone, this 
restriction on offsets may no longer be necessary. However, the EPA did 
not provide a rationale for the wholesale removal of this restriction. 
Therefore, the EPA is making the proposed change, with some small 
variations. The provisions will be revised to update the list of 
negligible photochemical reactive compounds and to more clearly reflect 
the fact that the organic compounds listed with negligible 
photochemical reactivity are, by definition, not VOCs. At worst, the 
continued inclusion of this restriction on offsets is merely redundant. 
The EPA may consider whether to remove it in a future action. See 40 
CFR 51.100(s)(1) and paragraph IV.C.4. at part 51 Appendix S.
    4. In 1986, the NSR provisions in 40 CFR 51.18 were moved in a 
restructuring rule that placed them under new subpart I of part 51.\11\ 
40 CFR 51.18 is an obsolete reference to the NSR regulations that were 
applicable to minor sources, major sources locating in areas that do 
not meet the National Ambient Air Quality Standards (NAAQS) (40 CFR 
51.18(j)), and major sources locating in areas that meet the NAAQS, but 
significantly impact an area that is not meeting the NAAQS (40 CFR 
51.18(k)). Subpart I now contains the preconstruction review 
requirements for state minor NSR programs (40 CFR 51.160-164) as well 
as state major NNSR programs (40 CFR

[[Page 37922]]

51.165) and state PSD programs (40 CFR 51.166).\12\ The EPA proposed to 
update the reference to 40 CFR 51.18 in Appendix S V.A. by replacing it 
with a reference to 40 CFR 51.165, which includes NSR requirements for 
major stationary sources in nonattainment areas. See proposed section 
V.A. [2nd paragraph] of 40 CFR part 51, Appendix S. The EPA received 
two comments supporting this change as proposed and received no adverse 
comments regarding this proposed change. Upon review for the final 
rule, the EPA determined that the citation referencing 40 CFR 51.165 
should be changed to 40 CFR 51.102 since the reference in Appendix S 
Paragraph V.A. concerns the proper public participation process for a 
state implementation revision if necessary to make an offset 
enforceable. 40 CFR 51.102 addresses the public notice for the 
preparation, adoption and submittal of implementation plans and is 
therefore a more appropriate reference than the proposed reference to 
40 CFR 51.165.
---------------------------------------------------------------------------

    \11\ 51 FR 40656 (November 7, 1986).
    \12\ Subpart I of part 51 also contains the PSD regulations at 
40 CFR 51.166, which were previously codified at 40 CFR 51.24.
---------------------------------------------------------------------------

    5. On December 31, 2002, the EPA amended its NSR regulations to 
add, among other things, provisions for Plantwide Applicability 
Limitations (PALs).\13\ In each of the NSR regulations, new provisions 
were added to require major stationary sources with PAL permits to 
monitor affected emissions units in accordance with monitoring 
requirements set forth elsewhere in the regulations. The PSD 
regulations at 40 CFR 51.166 incorrectly provided a reference to the 
recordkeeping requirements under paragraph (w)(13) instead of the 
intended monitoring requirements for PALs at paragraph (w)(12). The 
other NSR regulations provided the correct cross reference to the 
monitoring requirements. The EPA proposed to correctly reference the 
monitoring requirements for PALs in 40 CFR 51.166(w)(7)(vii). The EPA 
received no adverse comments on this proposed change and will therefore 
finalize the change as proposed.
---------------------------------------------------------------------------

    \13\ 67 FR 80186 (December 31, 2002).
---------------------------------------------------------------------------

    6. On December 21, 2007, the EPA amended the NSR regulations by, 
among other things, adding new paragraphs to explain when a stationary 
source will have a ``reasonable possibility'' of causing a significant 
emissions increase.\14\ In 40 CFR 51.166(r)(6)(vi)(b), reference is 
incorrectly made to ``paragraph (a)(6)(vi)(a)'' and ``paragraphs 
(a)(6)(ii) through (v).'' Both references mistakingly reference 
paragraph (a), which is where similar references are made in the 
``reasonable possibility'' provision contained in 40 CFR 
51.165(a)(6)(vi)(B). The EPA proposed to correct the references in 40 
CFR 51.166 by changing the language to reference the applicable 
subparagraphs under paragraph (r). The EPA did not receive any adverse 
comments on the proposed changes and will therefore finalize the 
changes as proposed.
---------------------------------------------------------------------------

    \14\ 72 FR 72607 (December 21, 2007).
---------------------------------------------------------------------------

    E. Clean Air Act Amendments. Some of the corrections result from 
new statutory requirements introduced in the 1990 CAA Amendments, which 
the EPA did not address in subsequent rulemakings involving the 
affected NSR regulations.
    1. Major source threshold for municipal incinerators. The 1990 CAA 
Amendments amended the definition of ``major emitting facility'' at 
section 169(1) by striking out the words ``two hundred and'' as those 
words appeared in the phrase ``municipal incinerators capable of 
charging more than two hundred and fifty tons of refuse per day.'' \15\ 
This amendment had the effect of lowering the charging capacity 
threshold for qualifying a municipal incinerator as a ``major emitting 
facility'' from 250 tons of refuse per day to 50 tons per day when such 
incinerator emits or has the potential to emit at least 100 tons per 
year of any regulated NSR pollutant. In the 2019 NPRM, the EPA proposed 
to revise all four sets of major NSR regulations to reflect this change 
with regards to the statutory definition of ``major emitting facility'' 
for municipal incinerators. See proposed 40 CFR part 51 Appendix S 
II.A.4.(iii)(h), Appendix S II.F.8, 40 CFR 51.165(a)(1)(iv)(C)(8), 
51.165(a)(4)(viii), 51.166(b)(1)(i)(a), 51.166(b)(1)(iii)(h), 
51.166(i)(1)(ii)(h), 52.21(b)(1)(i)(a), 52.21(b)(1)(iii)(h), and 
52.21(i)(1)(vii)(h). The EPA did not receive any adverse comments on 
the proposed changes and will finalize the changes as proposed.
---------------------------------------------------------------------------

    \15\ Par. (1). Public Law 101-549, section 305(b) (1990).
---------------------------------------------------------------------------

    2. Standards under section 112 of the Act. The NSR regulations in 
several places refer to emissions standards established pursuant to 40 
CFR part 61. See e.g., 40 CFR 51.166(b)(12). Part 61 contains national 
emission standards for hazardous air pollutants (NESHAP), which the EPA 
promulgated based on the pre-1990 CAA Amendment version of section 112. 
The 1990 CAA Amendments revised section 112, causing the EPA to 
promulgate additional NESHAP, which are included in part 63. 
Accordingly, to ensure that the requirements associated with the 
section 112 standards are adequately addressed in the NSR regulations, 
the EPA proposed that each regulatory reference to part 61 should also 
include a reference to part 63. The EPA proposed to make the necessary 
updates in the affected NSR regulations.
    Several commenters recommended various options that differed from 
the 2019 EPA proposal. A state agency commenter recommended that the 
EPA add reference to not only part 63 but also to part 62. This, the 
commenter noted, would ``include all potentially applicable federal 
standards'' to specific provisions under the affected NSR regulations. 
40 CFR part 62 sets forth the Administrator's approval and disapproval 
of state plans for the control of pollutants from facilities regulated 
under CAA 111(d) and 129 and the Administrator's promulgation of such 
plans or portions of plans when a state has failed to provide an 
approvable plan or portions thereof. Plans under part 62 contain 
standards of performance that apply to existing sources that would be 
subject to 40 CFR part 60 (standards of performance for new stationary 
sources) if such existing sources were new sources. Such plans are 
approved state plans or federal plans for each separate source 
category.
    Two commenters claimed that the EPA has incorrectly proposed to add 
reference to part 63 because the CAA at section 112(b)(6), added to the 
Act in 1990, explicitly removes section 112 hazardous air pollutants 
(HAPs) from the PSD program. One of the commenters noted that the NNSR 
program ``inherently does not directly regulate a HAP as it is not a 
criteria pollutant with a national ambient air quality standard.'' 
Thus, the commenters argued that the EPA was incorrect in proposing to 
add reference to part 63 and should additionally be removing reference 
to part 61, which also contains standards for HAPs. One of the 
commenters concluded that ``including part 61 and, as proposed, part 63 
in various NSR definitions will give the mistaken impression that HAPs 
are regulated by the NSR programs.'' The commenters acknowledged that 
the statutory definition of ``best available control technology'' did 
include a reference to standards promulgated pursuant to CAA section 
112; therefore, one of the commenters recommended that ``[i]n order to 
reduce confusion from the insertion of parts 61 and 63 to the PSD BACT 
requirements and to remain consistent with the 1991 transitional 
guidance, EPA should clarify in the rule that BACT applies to a 
regulated NSR pollutant by adding the term `for a regulated NSR 
pollutant'

[[Page 37923]]

after the term `major stationary source or major modification' in 40 
CFR 51.166(j)(1) and 52.21(j)(1).''
    One commenter was concerned about the EPA's 2019 proposal to add 
reference to part 63 to the definition of ``allowable emissions.'' The 
commenter indicated that the addition of a reference to part 63 therein 
would indicate that Congress intended that compliance with limits 
issued under CAA section 112, as amended in 1990, should not be 
considered creditable reductions for netting purposes. The commenter 
further stated that ``there is no indication that Congress intended 
Maximum Achievable Control Technology (`MACT') (or CAA section 112(f)) 
reductions to be excluded under a creditability rationale.'' Moreover, 
the commenter argued that ``[i]f EPA intends this result . . . then the 
agency must do it in a more substantive rulemaking, not as part of this 
`error correction' rulemaking.''
    In light of several commenters' adverse comments expressing 
concerns about adding a reference to part 63 emissions standards to the 
NSR regulations, the EPA has decided not to finalize the proposed 
changes concerning the part 63 reference, with one exception. The EPA 
agrees that additional assessment is needed to determine how including 
HAPs in the definitions of ``allowable emissions'' and ``federally 
enforceable'' would function in practice and whether the commenters' 
concerns are justified. However, in one particular case--the definition 
of ``BACT''--the statute expressly requires the inclusion of emissions 
standards under CAA section 112 in that definition (which includes 
emissions limitations contained in both 40 CFR parts 61 and 63). By 
adding the restriction that BACT cannot allow emissions in excess of 
112 standards, the EPA is not suggesting that HAPs are regulated under 
NSR. Rather, there are certain NSR regulated pollutants that inherently 
include HAP pollutants. For instance, PM may contain constituents that 
include HAPs, such as cadmium. By including the CAA section 112 
standards in the restriction in the definition of BACT, the EPA is 
ensuring that BACT cannot allow emissions of HAPs in excess of any 
applicable section 112 standard under 40 CFR parts 61 and 63. See 
revised 40 CFR 51.165(a)(1)(xl), 51.166(b)(12), part 51 Appendix S 
II.A.34, and 52.21(b)(12).
    F. Outdated exemptions. The PSD regulations at 40 CFR 51.166 and 
52.21 contain various exemption provisions that allow certain permit 
applicants--e.g., portable stationary sources and nonprofit health or 
nonprofit educational institutions--to be exempt from all or a portion 
of the PSD preconstruction review requirements. In some cases, these 
provisions allowed permit applicants to be excluded from certain 
requirements--e.g., new or revised PM2.5 NAAQS or PSD 
increments--which became effective before a final permit could be 
issued, commonly known as PM2.5 grandfathering provisions 
(see 40 CFR 51.166(i)(10) and 52.21(i)(11)). Some of the existing 
exemption provisions are outdated because the time in which they were 
relevant has long since passed. Accordingly, the EPA proposed to remove 
such outdated provisions, which allow for grandfathering or the 
implementation of alternative procedures for PSD permit applicants, 
under the regulations at 40 CFR 51.166 and 52.21.
    The EPA received a few adverse comments concerning the proposed 
removal of outdated exemptions. One of these comments pertained to an 
exemption that the EPA did not actually propose to remove. The 
commenter correctly pointed out that the PSD exemption applicable to 
portable sources, 40 CFR 52.21(i)(1)(viii), continues to be relevant 
and should not be removed. The EPA acknowledges that the preamble text 
indicated that the EPA proposed to delete paragraphs (i)(1)(viii) 
through (x) of the 40 CFR 52.21 PSD regulations, which include the 
portable source provision at paragraph (i)(1)(viii). However, it was 
not the EPA's intention to delete paragraph (i)(1)(viii) and a review 
of the proposed regulatory text and the Error Corrections Table in the 
docket shows that the EPA did not actually include the deletion of this 
paragraph in the 2019 proposal. Instead, the proposed regulatory text 
shows the deletion of only paragraphs (i)(1)(ix) and (x). Accordingly, 
the EPA is not deleting the portable source exemption provision at 40 
CFR 52.21(i)(1)(viii) in this final action. As proposed, the EPA is 
deleting the following outdated exemption provisions in the final rule: 
40 CFR 51.166(i)(6) through (11); 52.21(i)(1)(i) through (v), 
52.21(i)(6) through (12), and 52.21(m)(1)(v), and 52.21(m)(1)(vii) and 
(viii) and 52.21(i)(1)(ix) and (x).
    The EPA received one comment asking that the EPA retain the 
outdated exclusion of carbon dioxide emissions from biogenic material 
(the combustion or decomposition of non-fossilized and biodegradable 
organic material originating from plants, animals, or micro-organisms) 
from the definition of ``subject to regulation.'' This temporary 
exclusion was vacated by a court in 2013 \16\ and expired on its own 
terms on July 21, 2014. The commenter suggested that, because this 
expiration was relatively recent, ``[r]etaining this language will aid 
regulatory personnel, owners/operators, and consultants in the future 
when trying to fully understand the basis for recent NSR permitting 
determinations based on EPA's prior GHG requirements.'' The EPA is not 
persuaded that this justifies retaining the vacated and outdated 
provision. If anyone seeks to understand the basis of older NSR 
permitting decisions, they can consult the version of the Code of 
Federal Regulations that applied at the time of those decisions. 
Therefore, the EPA is finalizing removal of the vacated and outdated 
exclusion of carbon dioxide emissions from biogenic material from the 
definition of ``subject to regulation.'' See 40 CFR 
51.166(b)(48)(ii)(a) and 52.21(b)(49)(ii)(a).
---------------------------------------------------------------------------

    \16\ Center for Biological Diversity v. EPA, 722 F.3d 401 (D.C. 
Cir. 2013).
---------------------------------------------------------------------------

III. Final Action

    This final action corrects minor, inadvertent, and non-substantive 
errors in 40 CFR parts 51 and 52 which govern NSR permitting programs, 
and updates the regulatory text to reflect statutory changes and 
certain court decisions vacating elements of the regulatory text, but 
does not change the requirements within these programs. Based upon 
comments received, as noted in this preamble and the RTC document in 
the docket, the EPA is moving forward with the majority of the proposed 
minor edits without change. Additionally, regarding state SIP 
submittals, the 2019 NPRM proposed that states need not be subject to 
any deadline to make conforming changes. The EPA received one comment 
in support of this position and no adverse comments. The EPA is 
therefore reaffirming that states can have discretion as to when to 
make these changes and may choose to combine them with other SIP 
submittals. Also, please refer to the RTC for further discussion about 
comments which are not included in Section II of this final rule 
preamble.

IV. Removal of Vacated Ozone NAAQS Grandfathering and Ozone 
Interprecursor Trading Provisions

    This final action removes an exemption in the PSD regulations 
vacated by the D.C. Circuit in 2019 as well as the ozone interprecursor 
trading (IPT provision in the NNSR regulations vacated by the D.C. 
Circuit in 2021. This section explains the court's vacatur of

[[Page 37924]]

these provisions and the basis for their removal.
    On October 26, 2015, the EPA promulgated a final rule containing 
revised NAAQS for ozone and grandfathering provisions that enabled 
pending PSD permit applications to be issued on the basis of a 
demonstration that the proposed source would not cause or contribute to 
a violation of the prior ozone NAAQS in effect at the time the permit 
application was deemed to be complete or noticed for public 
comment.\17\ The PSD grandfathering provisions were promulgated as a 
transition plan to reduce delays to pending PSD permit applications 
that may have otherwise been caused by the revised ozone standards. The 
PSD regulations implement CAA section 165(a)(3)(B) at 40 CFR 
52.21(k)(1) and 51.166(k)(1) and require that PSD permit applications 
include a demonstration that emissions from the proposed facility will 
not cause or contribute to a violation of any NAAQS, which generally 
means any NAAQS in effect on the date of a PSD permit issuance. Absent 
the PSD grandfathering provision, this demonstration requirement would 
have applied to the 2015 ozone NAAQS in any PSD permit application 
pending at the time the 2015 ozone NAAQS became effective. However, on 
August 23, 2019, the U.S. Court of Appeals for the District of Columbia 
Circuit concluded that the EPA lacked the authority to grandfather 
pending PSD permit applications in this manner and vacated the ozone 
NAAQS grandfathering provisions in a decision resolving challenges 
brought by industry, state, and environmental and public health 
petitioners to the 2015 primary and secondary ozone NAAQS and the PSD 
grandfathering provisions that were promulgated with these 
standards.\18\
---------------------------------------------------------------------------

    \17\ 80 FR 65292 (October 26, 2015).
    \18\ Murray Energy Corp. v. EPA, 936 F.3d 597 (D.C. Cir. 2019).
---------------------------------------------------------------------------

    On December 6, 2018, the EPA promulgated the final implementation 
rules for the 2015 ozone NAAQS, including provisions to address for 
ozone ground level ozone precursors Oxides of Nitrogen (NOX) 
and VOC. The provisions at 51.165(a)(11)(i) and Part 51 Appendix S 
Paragraph IV.G.5. were promulgated to allow permit applications to use 
IPT to satisfy the NNSR offset requirement for ozone in nonattainment 
areas. The IPT provisions were designed to support the EPA's long-
standing policy allowing NNSR permit applicants to satisfy their offset 
obligation for ozone precursors substituting NOX for VOC, or 
vice versa, supported by a technical demonstration showing an 
equivalent, or greater, air quality benefit with respect to ground 
level ozone concentrations in the ozone nonattainment area.\19\ On 
January 29, 2021, the D.C. Circuit concluded that Ozone IPT is not 
permissible under the CAA and vacated this part of the 2018 
regulation.\20\ Thus, in this action, EPA is removing the language 
allowing interprecursor trading for ozone and restoring the language in 
the NNSR regulations to the form it was in after the EPA's 2008 
PM2.5 implementation rule.
---------------------------------------------------------------------------

    \19\ 83 FR 62998 (December 6, 2018).
    \20\ Sierra Club v. EPA, No. 15-1465 (D.C. Cir. 2021).
---------------------------------------------------------------------------

    The EPA did not include the removal of these court-vacated 
provisions at 40 CFR 51.166(i)(11), 52.21(i)(12), 51.165(a)(11) and 
Part 51 Appendix S Paragraph IV.G.5. in the proposal to this rule. 
However, the EPA is adding this action to this final rule without 
providing an opportunity for public comment or a public hearing because 
the EPA finds that the Administrative Procedure Act (APA) good cause 
exemption applies here. In general, the APA and section 307(d) of the 
CAA require that general notice of proposed rulemakings shall be 
published in the Federal Register. Such notice must provide an 
opportunity for public participation in the rulemaking process. 
However, the APA and section 307(d) of the CAA provide an avenue for an 
agency to directly issue a final rulemaking in certain specific 
instances. This may occur, in particular, when an agency for good cause 
finds (and incorporates the finding and a brief statement of reasons in 
the rule issued) that notice and public procedure thereon are 
impracticable, unnecessary or contrary to the public interest. See 5 
U.S.C. 553(b)(3)(B); 42 U.S.C. 7407(d)(1). The EPA has determined that 
it is not necessary to provide a public hearing or an opportunity for 
public comment on this action because amending the regulations to 
remove the vacated grandfathering and ozone IPT provisions is a 
necessary ministerial act. Since the court vacated these provisions, 
the EPA no longer has the authority to allow the use of the affected 
provisions. Therefore, in as much as this action to remove the affected 
regulatory text simply implements the decision of the court, providing 
an opportunity for public comment or a public hearing on this issue 
would serve no useful purpose.
    In addition, providing notice and comment would be contrary to the 
public interest because it would unnecessarily delay the removal of the 
unlawful grandfathering and ozone IPT provisions from the Code of 
Federal Regulations, which could result in confusion for the regulated 
industry and state, local, and tribal air agencies about the PSD and 
NNSR regulations and permitting. Promulgation of this rule serves to 
clarify that sources cannot continue to demonstrate their compliance 
with the PSD and NNSR requirements by relying on the prior ozone NAAQS, 
or ozone IPT, respectively, as was previously allowed. It is thus in 
the public interest for the EPA to remove the PSD Grandfathering and 
Ozone IPT provisions without delay. Consistent with the approach 
described in section III, the EPA is not establishing a deadline in 
this rule for states to remove these provisions form the SIPs. States 
thus have the discretion as to when they amend their SIPs to remove the 
Ozone PSD grandfathering and Ozone IPT provisions and may combine such 
changes with other SIP submittals.
    For these reasons, the EPA finds good cause to issue a final 
rulemaking to remove the ozone NAAQS grandfathering and ozone NNSR IPT 
provisions pursuant to section 553 of the APA, 5 U.S.C. 553(b)(B). 
Therefore, the requirements of CAA section 307(d), including the 
requirement for public comment and hearing on proposed rulemakings, do 
not apply to this action.

V. Environmental Justice Considerations

    This action corrects minor, inadvertent, and non-substantive errors 
in 40 CFR parts 51 and 52 governing NSR permitting programs and updates 
the regulatory text to reflect statutory changes and certain court 
decisions vacating elements of the regulatory text but does not change 
the requirements within these programs. Therefore, this final rule will 
not change the protection for all those residing, working, attending 
school, or otherwise present in the applicable areas, regardless of 
minority and economic status. Further, this action will not have 
potential disproportionately high and adverse human health or 
environmental effects on minority, low-income, or indigenous 
populations.

VI. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    This action is not a significant regulatory action and was, 
therefore, not

[[Page 37925]]

submitted to the Office of Management and Budget (OMB) for review.

B. Paperwork Reduction Act (PRA)

    This action does not impose an information collection burden under 
the PRA. This action is clerical in nature and addresses non-
controversial edits to errors in the NSR regulatory text. Therefore, 
this final rulemaking does not impose any new information collection 
burden under the PRA. OMB has previously approved the information 
collection activities contained in the existing regulations and has 
assigned OMB control number 2060-0003.

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA. In 
making this determination, the impact of concern is any significant 
adverse economic impact on small entities. An agency may certify that a 
rule will not have a significant economic impact on a substantial 
number of small entities if the rule relieves regulatory burden, has no 
net burden or otherwise has a positive economic effect on the small 
entities subject to the rule. This action corrects minor, inadvertent 
and non-substantive errors in existing rules. We have therefore 
concluded that this action will have no net regulatory burden for all 
directly regulated small entities.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain any unfunded mandate as described in 
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect 
small governments. The action imposes no enforceable duty on any state, 
local or tribal governments or the private sector. This action corrects 
minor, inadvertent and non-substantive errors in existing rules.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial direct effects on the states, on the relationship between 
the national government and the states, or on the distribution of power 
and responsibilities among the various levels of government.

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    This action does not have tribal implications as specified in 
Executive Order 13175. This action only makes technical amendments to 
correct minor, inadvertent, and non-substantive errors in existing 
rules. None of these technical amendments has a substantial direct 
effect on any tribal land; thus, Executive Order 13175 does not apply 
to this action.

G. Executive Order 13045: Protection of Children From Environmental 
Health and Safety Risks

    The EPA interprets Executive Order 13045 as applying only to those 
regulatory actions that concern environmental health or safety risks 
that the EPA has reason to believe may disproportionately affect 
children, per the definition of ``covered regulatory action'' in 
section 2-202 of the Executive Order. This action is not subject to 
Executive Order 13045 because it does not concern an environmental 
health risk or safety risk.

H. Executive Order 13211: Actions That Significantly Affect Energy 
Supply, Distribution or Use

    This action is not subject to Executive Order 13211, because it is 
not a significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act (NTTAA)

    This rulemaking does not involve technical standards.

J. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations

    This action does not have disproportionately high and adverse human 
health or environmental effects on minority populations, low-income 
populations, and/or indigenous peoples, as specified in Executive Order 
12898 (59 FR 7629, February 16, 1994).
    The documentation for this decision is contained in Section IV of 
this preamble titled ``Environmental Justice Considerations.'' This 
action makes technical amendments to correct minor, inadvertent, and 
non-substantive errors to existing rules.

K. Congressional Review Act (CRA)

    This action is subject to the CRA, and the EPA will submit a rule 
report to each House of the Congress and to the Comptroller General of 
the United States. This action is not a ``major rule'' as defined by 5 
U.S.C. 804(2).

L. Judicial Review

    Under CAA section 307(b)(1), petitions for judicial review of any 
nationally applicable regulation, or any action the Administrator 
``finds and publishes'' as based on a determination of nationwide scope 
or effect must be filed in the United States Court of Appeals for the 
District of Columbia Circuit within 60 days of the date the 
promulgation, approval, or action appears in the Federal Register.\21\ 
These technical amendments are nationally applicable, as it corrects 
minor, inadvertent, and non-substantive errors to existing rules. As a 
result, petitions for review of this final action must be filed in the 
United States Court of Appeals for the District of Columbia Circuit by 
September 17, 2021. Filing a petition for reconsideration by the 
Administrator of this final action does not affect the finality of this 
action for the purposes of judicial review nor does it extend the time 
within which a petition for judicial review must be filed and shall not 
postpone the effectiveness of this action.\22\
---------------------------------------------------------------------------

    \21\ 42 U.S.C. 7607(b)(1).
    \22\ 42 U.S.C. 7607(d)(7)(B).
---------------------------------------------------------------------------

VII. Statutory Authority

    The statutory authority for this action is provided by 42 U.S.C. 
7401, et seq.

List of Subjects

40 CFR Part 51

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Carbon monoxide, Intergovernmental relations, 
Lead, National Ambient Air Quality Standards, New Source Review, 
Nitrogen dioxide, Ozone, Particulate matter, Preconstruction 
permitting, Sulfur oxides, Transportation, Volatile organic compounds.

40 CFR Part 52

    Environmental protection, Administrative practice and procedure, 
Air pollution control, BACT, Carbon monoxide, Incorporation by 
reference, Intergovernmental relations, Lead, National Ambient Air 
Quality Standards, New Source Review, Nitrogen dioxide, Ozone, 
Particulate matter, Preconstruction permitting, Sulfur oxides, Volatile 
organic compounds.

Michael S. Regan,
Administrator.

    For the reasons set forth in the preamble, title 40, chapter I of 
the Code of Federal Regulations is amended as follows:

[[Page 37926]]

PART 51--REQUIREMENTS FOR PREPARATION, ADOPTION AND SUBMITTAL OF 
IMPLEMENTATION PLANS

0
1. The authority citation for part 51 continues to read as follows:

    Authority: 42 U.S.C. 7401, et seq.

Subpart I--Review of New Sources and Modifications

0
2. Amend Sec.  51.165 by:
0
a. Revising paragraph (a)(1)(iv)(C)(8);
0
b. Revising paragraph (a)(1)(v)(C)(1);
0
c. Revising paragraph (a)(1)(v)(C)(5)(i);
0
d. Revising paragraph (a)(1)(v)(C)(6);
0
e. Revising paragraph (a)(1)(viii);
0
f. Revising paragraph (a)(1)(xxi)(A) through (D);
0
g. Revising paragraph (a)(1)(xl);
0
h. Removing paragraphs (a)(1)(xliii) through (xlvi);
0
i. Revising paragraph (a)(2)(ii)(A);
0
j. Adding paragraph (a)(2)(iii);
0
k. Revising paragraph (a)(3)(ii)(D);
0
l. Revising paragraph (a)(4)(viii);
0
m. Revising paragraph (a)(11); and
0
n. Removing and reserving paragraph (h);
    The revisions read as follows:


Sec.  51.165  Permit requirements.

    (a) * * *
    (1) * * *
    (iv) * * *
    (C) * * *
    (8) Municipal incinerators capable of charging more than 50 tons of 
refuse per day;
* * * * *
    (v) * * *
    (C) * * *
    (1) Routine maintenance, repair and replacement;
* * * * *
    (5) * * *
    (i) The source was capable of accommodating before December 21, 
1976, unless such change would be prohibited under any federally 
enforceable permit condition which was established after December 12, 
1976, pursuant to 40 CFR 52.21 or under regulations approved pursuant 
to 40 CFR part 51, subpart I.
* * * * *
    (6) An increase in the hours of operation or in the production 
rate, unless such change is prohibited under any federally enforceable 
permit condition which was established after December 21, 1976, 
pursuant to 40 CFR 52.21 or regulations approved pursuant to 40 CFR 
part 51, subpart I.
* * * * *
    (viii) Secondary emissions means emissions which would occur as a 
result of the construction or operation of a major stationary source or 
major modification, but do not come from the major stationary source or 
major modification itself. For the purpose of this section, secondary 
emissions must be specific, well defined, quantifiable, and impact the 
same general area as the stationary source or modification which causes 
the secondary emissions. Secondary emissions include emissions from any 
offsite support facility which would not be constructed or increase its 
emissions except as a result of the construction or operation of the 
major stationary source or major modification. Secondary emissions do 
not include any emissions which come directly from a mobile source, 
such as emissions from the tailpipe of a motor vehicle, from a train, 
or from a vessel.
* * * * *
    (xxi) * * *
    (A) The emissions unit is a reconstructed unit within the meaning 
of Sec.  60.15(b)(1) of this chapter, or the emissions unit completely 
takes the place of an existing emissions unit;
    (B) The emissions unit is identical to or functionally equivalent 
to the replaced emissions unit;
    (C) The replacement does not alter the basic design parameters of 
the process unit; and
    (D) The replaced emissions unit is permanently removed from the 
major stationary source, otherwise permanently disabled, or permanently 
barred from operation by a permit that is enforceable as a practical 
matter. If the replaced emissions unit is brought back into operation, 
it shall constitute a new emissions unit.
* * * * *
    (xl) Best available control technology (BACT) means an emissions 
limitation (including a visible emissions standard) based on the 
maximum degree of reduction for each regulated NSR pollutant which 
would be emitted from any proposed major stationary source or major 
modification which the reviewing authority, on a case-by-case basis, 
taking into account energy, environmental, and economic impacts and 
other costs, determines is achievable for such source or modification 
through application of production processes or available methods, 
systems, and techniques, including fuel cleaning or treatment or 
innovative fuel combustion techniques for control of such pollutant. In 
no event shall application of best available control technology result 
in emissions of any pollutant which would exceed the emissions allowed 
by any applicable standard under 40 CFR part 60, 61, or 63. If the 
reviewing authority determines that technological or economic 
limitations on the application of measurement methodology to a 
particular emissions unit would make the imposition of an emissions 
standard infeasible, a design, equipment, work practice, operational 
standard, or combination thereof, may be prescribed instead to satisfy 
the requirement for the application of BACT. Such standard shall, to 
the degree possible, set forth the emissions reduction achievable by 
implementation of such design, equipment, work practice or operation, 
and shall provide for compliance by means which achieve equivalent 
results.
* * * * *
    (2) * * *
    (ii) * * *
    (A) Except as otherwise provided in paragraph (a)(2)(iii) of this 
section, and consistent with the definition of major modification 
contained in paragraph (a)(1)(v)(A) of this section, a project is a 
major modification for a regulated NSR pollutant (as defined in 
paragraph (a)(1)(xxxvii) of this section) if it causes two types of 
emissions increases--a significant emissions increase (as defined in 
paragraph (a)(1)(xxvii) of this section) and a significant net 
emissions increase (as defined in paragraphs (a)(1)(vi) and (x) of this 
section). The project is not a major modification if it does not cause 
a significant emissions increase. If the project causes a significant 
emissions increase, then the project is a major modification only if it 
also results in a significant net emissions increase.
* * * * *
    (iii) The plan shall require that for any major stationary source 
with a PAL for a regulated NSR pollutant, the major stationary source 
shall comply with requirements under paragraph (f) of this section.
    (3) * * *
    (ii) * * *
    (D) No emissions credit may be allowed for replacing one 
hydrocarbon compound with another of lesser reactivity, except that 
emissions credit may be allowed for the replacement with those 
compounds listed as having negligible photochemical reactivity in Sec.  
51.100(s).
* * * * *
    (4) * * *
    (viii) Municipal incinerators capable of charging more than 50 tons 
of refuse per day;
* * * * *
    (11) The plan shall require that, in meeting the emissions offset 
requirements of paragraph (a)(3) of this section, the emissions offsets 
obtained shall be for the same regulated NSR

[[Page 37927]]

pollutant, unless interprecursor offsetting is permitted for a 
particular pollutant as specified in this paragraph. The plan may allow 
the offset requirements in paragraph (a)(3) of this section for direct 
PM2.5 emissions or emissions of precursors of 
PM2.5 to be satisfied by offsetting reductions in direct 
PM2.5 emissions or emissions of any PM2.5 
precursor identified under paragraph (a)(1)(xxxvii)(C) of this section 
if such offsets comply with the interprecursor trading hierarchy and 
ratio established in the approved plan for a particular nonattainment 
area.
* * * * *

0
3. Amend Sec.  51.166 by:
0
a. Revising paragraph (a)(7) introductory text;
0
b. Revising paragraph (a)(7)(iv)(a);
0
c. Revising paragraph (a)(7)(v);
0
d. Revising paragraphs (b)(1)(i)(a) and (c);
0
e. Revising paragraph (b)(1)(iii)(h);
0
f. Revising paragraph (b)(1)(iii)(z);
0
g. Revising paragraph (b)(2)(iii)(a);
0
h. Revising paragraph (b)(2)(iii)(e)(1);
0
i. Revising paragraph (b)(2)(iii)(f);
0
j. Removing and reserving paragraph (b)(3)(iii)(c);
0
k. Revising paragraph (b)(12);
0
l. Revising paragraph (b)(23)(ii);
0
m. Revising paragraphs (b)(32)(i) through (iv);
0
n. Revising paragraph (b)(48)(i);
0
o. Revising paragraphs (b)(48)(ii) introductory text and 
(b)(48)(ii)(a);
0
p. Revising paragraph (b)(48)(iii);
0
q. Revising paragraph (b)(48)(iv)(b);
0
r. Removing paragraphs (b)(53) through (56);
0
s. Revising paragraph (g)(4);
0
t. Revising paragraph (i)(1)(ii)(h);
0
u. Removing and reserving paragraphs (i)(6) through (11);
0
v. Revising paragraphs (j)(1) and (2);
0
w. Revising paragraph (j)(4);
0
x. Revising paragraph (k)(1) introductory text;
0
y. Revising paragraph (m)(1)(iii);
0
z. Revising paragraphs (p)(3) and (4);
0
aa. Revising paragraphs (p)(5)(i) and (iii);
0
bb. Revising paragraph (p)(6)(iii);
0
cc. Revising paragraph (p)(7) introductory text;
0
dd. Revising paragraph (r)(2);
0
ee. Revising paragraph (r)(6)(vi)(b);
0
ff. Revising paragraph (w)(7)(vii);
0
gg. Revising paragraph (w)(9)(ii); and
0
hh. Removing paragraph (y).
    The revisions read as follows:


 Sec.  51.166  Prevention of significant deterioration of air quality.

    (a) * * *
    (7) Applicability. Each plan shall contain procedures that 
incorporate the requirements in paragraphs (a)(7)(i) through (v) of 
this section.
* * * * *
    (iv) * * *
    (a) Except as otherwise provided in paragraph (a)(7)(v) of this 
section, and consistent with the definition of major modification 
contained in paragraph (b)(2) of this section, a project is a major 
modification for a regulated NSR pollutant if it causes two types of 
emissions increases--a significant emissions increase (as defined in 
paragraph (b)(39) of this section), and a significant net emissions 
increase (as defined in paragraphs (b)(3) and (23) of this section). 
The project is not a major modification if it does not cause a 
significant emissions increase. If the project causes a significant 
emissions increase, then the project is a major modification only if it 
also results in a significant net emissions increase.
* * * * *
    (v) The plan shall require that for any major stationary source 
with a PAL for a regulated NSR pollutant, the major stationary source 
shall comply with requirements under paragraph (w) of this section.
    (b) * * *
    (1)(i) * * *
    (a) Any of the following stationary sources of air pollutants which 
emits, or has the potential to emit, 100 tons per year or more of any 
regulated NSR pollutant: Fossil fuel-fired steam electric plants of 
more than 250 million British thermal units per hour heat input, coal 
cleaning plants (with thermal dryers), kraft pulp mills, portland 
cement plants, primary zinc smelters, iron and steel mill plants, 
primary aluminum ore reduction plants (with thermal dryers), primary 
copper smelters, municipal incinerators capable of charging more than 
50 tons of refuse per day, hydrofluoric, sulfuric, and nitric acid 
plants, petroleum refineries, lime plants, phosphate rock processing 
plants, coke oven batteries, sulfur recovery plants, carbon black 
plants (furnace process), primary lead smelters, fuel conversion 
plants, sintering plants, secondary metal production plants, chemical 
process plants (which does not include ethanol production facilities 
that produce ethanol by natural fermentation included in NAICS codes 
325193 or 312140), fossil-fuel boilers (or combinations thereof) 
totaling more than 250 million British thermal units per hour heat 
input, petroleum storage and transfer units with a total storage 
capacity exceeding 300,000 barrels, taconite ore processing plants, 
glass fiber processing plants, and charcoal production plants;
* * * * *
    (c) Any physical change that would occur at a stationary source not 
otherwise qualifying under paragraph (b)(1) of this section as a major 
stationary source, if the change would constitute a major stationary 
source by itself.
* * * * *
    (iii) * * *
    (h) Municipal incinerators capable of charging more than 50 tons of 
refuse per day;
* * * * *
    (z) Fossil fuel-fired steam electric plants of more than 250 
million British thermal units per hour heat input, and
* * * * *
    (2) * * *
    (iii) * * *
    (a) Routine maintenance, repair and replacement;
* * * * *
    (e) * * *
    (1) The source was capable of accommodating before January 6, 1975, 
unless such change would be prohibited under any federally enforceable 
permit condition which was established after January 6, 1975, pursuant 
to 40 CFR 52.21 or under regulations approved pursuant to 40 CFR part 
51, subpart I.
* * * * *
    (f) An increase in the hours of operation or in the production 
rate, unless such change would be prohibited under any federally 
enforceable permit condition which was established after January 6, 
1975, pursuant to 40 CFR 52.21 or under regulations approved pursuant 
to 40 CFR part 51, subpart I.
* * * * *
    (12) Best available control technology means an emissions 
limitation (including a visible emissions standard) based on the 
maximum degree of reduction for each regulated NSR pollutant which 
would be emitted from any proposed major stationary source or major 
modification which the reviewing authority, on a case-by-case basis, 
taking into account energy, environmental, and economic impacts and 
other costs, determines is achievable for such source or modification 
through application of production processes or available methods, 
systems, and techniques, including fuel cleaning or treatment or 
innovative fuel combination techniques for control of such pollutant. 
In no event shall application of best available control technology 
result in emissions of any pollutant which would exceed the emissions 
allowed by any applicable standard under 40 CFR part 60, 61, or 63. If 
the reviewing authority determines that technological or economic 
limitations on the application of measurement methodology to a 
particular emissions unit would make

[[Page 37928]]

the imposition of an emissions standard infeasible, a design, 
equipment, work practice, operational standard or combination thereof, 
may be prescribed instead to satisfy the requirement for the 
application of best available control technology. Such standard shall, 
to the degree possible, set forth the emissions reduction achievable by 
implementation of such design, equipment, work practice or operation, 
and shall provide for compliance by means which achieve equivalent 
results.
* * * * *
    (23) * * *
    (ii) Significant means, in reference to a net emissions increase or 
the potential of a source to emit a regulated NSR pollutant that 
paragraph (b)(23)(i) of this section does not list, any emissions rate.
* * * * *
    (32) * * *
    (i) The emissions unit is a reconstructed unit within the meaning 
of Sec.  60.15(b)(1) of this chapter, or the emissions unit completely 
takes the place of an existing emissions unit;
    (ii) The emissions unit is identical to or functionally equivalent 
to the replaced emissions unit;
    (iii) The replacement does not change the basic design parameter(s) 
of the process unit;-and
    (iv) The replaced emissions unit is permanently removed from the 
major stationary source, otherwise permanently disabled, or permanently 
barred from operation by a permit that is enforceable as a practical 
matter. If the replaced emissions unit is brought back into operation, 
it shall constitute a new emissions unit.
* * * * *
    (48) * * *
    (i) Greenhouse gases (GHGs), the air pollutant defined in Sec.  
86.1818-12(a) of this chapter as the aggregate group of six greenhouse 
gases: Carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, 
perfluorocarbons, and sulfur hexafluoride, shall not be subject to 
regulation except as provided in paragraph (b)(48)(iv) of this section.
    (ii) For purposes of paragraphs (b)(48)(iii) and (iv) of this 
section, the term tpy CO2 equivalent emissions 
(CO2e) shall represent an amount of GHGs emitted, and shall 
be computed as follows:
    (a) Multiplying the mass amount of emissions (tpy), for each of the 
six greenhouse gases in the pollutant GHGs, by the gas's associated 
global warming potential published at Table A-1 to subpart A of part 98 
of this chapter--Global Warming Potentials.
* * * * *
    (iii) The term emissions increase as used in paragraph (b)(48)(iv) 
of this section shall mean that both a significant emissions increase 
(as calculated using the procedures in paragraph (a)(7)(iv) of this 
section) and a significant net emissions increase (as defined in 
paragraphs (b)(3) and (23) of this section) occur. For the pollutant 
GHGs, an emissions increase shall be based on tpy CO2e, and 
shall be calculated assuming the pollutant GHGs is a regulated NSR 
pollutant and ``significant'' is defined as 75,000 tpy CO2e 
instead of applying the value in paragraph (b)(23)(ii) of this section.
    (iv) * * *
    (b) The stationary source is an existing major stationary source 
for a regulated NSR pollutant that is not GHGs, and also will have an 
emissions increase of a regulated NSR pollutant, and an emissions 
increase of 75,000 tpy CO2e or more.
* * * * *
    (g) * * *
    (4) The plan shall provide that lands within the exterior 
boundaries of Indian Reservations may be redesignated only by the 
appropriate Indian Governing Body. The appropriate Indian Governing 
Body may submit to the Administrator a proposal to redesignate areas 
Class I, Class II, or Class III provided that:
* * * * *
    (i) * * *
    (1) * * *
    (ii) * * *
    (h) Municipal incinerators capable of charging more than 50 tons of 
refuse per day;
* * * * *
    (j) * * *
    (1) A major stationary source or major modification shall meet each 
applicable emissions limitation under the State implementation plan and 
each applicable emission standard-and standard of performance under 40 
CFR part 60, 61, or 63.
    (2) A new major stationary source shall apply best available 
control technology for each regulated NSR pollutant that it would have 
the potential to emit in significant amounts.
* * * * *
    (4) For phased construction projects, the determination of best 
available control technology shall be reviewed and modified as 
appropriate at the latest reasonable time which occurs no later than 18 
months prior to commencement of construction of each independent phase 
of the project. At such time, the owner or operator of the applicable 
stationary source may be required to demonstrate the adequacy of any 
previous determination of best available control technology for the 
source.
    (k) * * *
    (1) Required demonstration. The plan shall provide that the owner 
or operator of the proposed source or modification shall demonstrate 
that allowable emission increases from the proposed source or 
modification, in conjunction with all other applicable emissions 
increases or reductions (including secondary emissions), would not 
cause or contribute to air pollution in violation of:
* * * * *
    (m) * * *
    (1) * * *
    (iii) The plan shall provide that with respect to any such 
pollutant (other than nonmethane hydrocarbons) for which such a 
standard does exist, the analysis shall contain continuous air quality 
monitoring data gathered for purposes of determining whether emissions 
of that pollutant would cause or contribute to a violation of the 
standard or any maximum allowable increase.
* * * * *
    (p) * * *
    (3) Denial--impact on air quality related values. The plan shall 
provide a mechanism whereby a Federal Land Manager of any such lands 
may present to the State, after the reviewing authority's preliminary 
determination required under procedures developed in accordance with 
paragraph (q) of this section, a demonstration that the emissions from 
the proposed source or modification would have an adverse impact on the 
air quality-related values (including visibility) of any Federal 
mandatory Class I lands, notwithstanding that the change in air quality 
resulting from emissions from such source or modification would not 
cause or contribute to concentrations which would exceed the maximum 
allowable increases for a Class I area. If the State concurs with such 
demonstration, the reviewing authority shall not issue the permit.
    (4) Class I variances. The plan may provide that the owner or 
operator of a proposed source or modification may demonstrate to the 
Federal Land Manager that the emissions from such source would have no 
adverse impact on the air quality related values of such lands 
(including visibility), notwithstanding that the change in air quality 
resulting from emissions from such source or modification would cause 
or contribute to concentrations which would exceed the maximum 
allowable increases for a Class I area. If the Federal land manager 
concurs with such demonstration and so certifies to

[[Page 37929]]

the State, the reviewing authority may, provided that the applicable 
requirements are otherwise met, issue the permit with such emission 
limitations as may be necessary to assure that emissions of sulfur 
dioxide, PM2.5, PM10, and nitrogen oxides would 
not exceed the following maximum allowable increases over minor source 
baseline concentration for such pollutants:
    (5) * * *
    (i) The owner or operator of a proposed source or modification 
which cannot be approved under procedures developed pursuant to 
paragraph (p)(4) of this section may demonstrate to the Governor that 
the source or modification cannot be constructed by reason of any 
maximum allowable increase for sulfur dioxide for periods of twenty-
four hours or less applicable to any Class I area and, in the case of 
Federal mandatory Class I areas, that a variance under this clause 
would not adversely affect the air quality related values of the area 
(including visibility);
* * * * *
    (iii) If such variance is granted, the reviewing authority may 
issue a permit to such source or modification in accordance with 
provisions developed pursuant to paragraph (p)(7) of this section 
provided that the applicable requirements of the plan are otherwise 
met.
    (6) * * *
    (iii) If such a variance is approved, the reviewing authority may 
issue a permit in accordance with provisions developed pursuant to the 
requirements of paragraph (p)(7) of this section provided that the 
applicable requirements of the plan are otherwise met.
    (7) Emission limitations for Presidential or gubernatorial 
variance. The plan shall provide that, in the case of a permit issued 
under procedures developed pursuant to paragraph (p)(5) or (6) of this 
section, the source or modification shall comply with emission 
limitations as may be necessary to assure that emissions of sulfur 
dioxide from the source or modification would not (during any day on 
which the otherwise applicable maximum allowable increases are 
exceeded) cause or contribute to concentrations which would exceed the 
following maximum allowable increases over the baseline concentration 
and to assure that such emissions would not cause or contribute to 
concentrations which exceed the otherwise applicable maximum allowable 
increases for periods of exposure of 24 hours or less for more than 18 
days, not necessarily consecutive, during any annual period:
* * * * *
    (r) * * *
    (2) The plan shall provide that at such time that a particular 
source or modification becomes a major stationary source or major 
modification solely by virtue of a relaxation in any enforceable 
limitation which was established after August 7, 1980, on the capacity 
of the source or modification otherwise to emit a pollutant, such as a 
restriction on hours of operation, then the requirements of paragraphs 
(j) through (r) of this section shall apply to the source or 
modification as though construction had not yet commenced on the source 
or modification.
* * * * *
    (6) * * *
    (vi) * * *
    (b) A projected actual emissions increase that, added to the amount 
of emissions excluded under paragraph (b)(40)(ii)(c) of this section, 
sums to at least 50 percent of the amount that is a ``significant 
emissions increase,'' as defined under paragraph (b)(39) of this 
section (without reference to the amount that is a significant net 
emissions increase), for the regulated NSR pollutant. For a project for 
which a reasonable possibility occurs only within the meaning of this 
paragraph (r)(6)(vi)(b), and not also within the meaning of paragraph 
(r)(6)(vi)(a) of this section, then the provisions under paragraphs 
(r)(6)(ii) through (v) of this section do not apply to the project.
* * * * *
    (w) * * *
    (7) * * *
    (vii) A requirement that the major stationary source owner or 
operator monitor all emissions units in accordance with the provisions 
under paragraph (w)(12) of this section.
* * * * *
    (9) * * *
    (ii) Each emissions unit(s) shall comply with the allowable 
emission limitation on a 12-month rolling basis. The reviewing 
authority may approve the use of monitoring systems (source testing, 
emission factors, etc.) other than CEMS, CERMS, PEMS, or CPMS to 
demonstrate compliance with the allowable emission limitation.
* * * * *

0
4. Appendix S to part 51 is amended:
0
a. In section I by revising the first two undesignated paragraphs;
0
b. In section II by:
0
i. Revising paragraph A.4.(i)(a);
0
ii. Revising paragraphs A.4.(iii) introductory text and A.4.(iii)(h);
0
iii. Revising paragraphs A.5.(iii)(e)(1) and (2) and (f);
0
iv. Revising paragraphs A.7.(ii) and A.34 and 35;
0
v. Adding paragraph A.37;
0
vi. Revising paragraph B;
0
vii. Revising paragraph F.(8); and
0
viii. Revising paragraph II.G;
0
c. In section III by:
0
i. Revising paragraphs B and C; and
0
ii. Revising paragraph D. Condition 1;
0
d. In section IV by:
0
i. Revising paragraphs A. Condition 1 and Condition 4;
0
ii. Revising paragraph B introductory text;
0
iii. Revising paragraph B.(i).1;
0
iv. Revising paragraph C.3.(i);
0
v. Revising paragraphs C.3.(ii) introductory text and C.3.(ii)(2);
0
vi. Revising paragraphs C.4 and 5;
0
vii. Revising paragraphs D and G.1 and 5;
0
viii. Revising paragraph H;
0
ix. Revising paragraph I.2;
0
x. Revising paragraph J.6.(ii); and
0
xi. Revising paragraph K.5 and paragraph K.14 introductory text; and
0
e. In section V by revising paragraph A.
    The revisions read as follows:

Appendix S to Part 51--Emission Offset Interpretative Ruling

I. Introduction

    This appendix sets forth EPA's Interpretative Ruling on the 
preconstruction review requirements for stationary sources of air 
pollution (not including indirect sources) under 40 CFR part 51, 
subpart I. A major new source or major modification which would 
locate in any area designated under section 107(d) of the Act as 
attainment or unclassifiable for ozone that is located in an ozone 
transport region or which would locate in an area designated in 40 
CFR part 81, subpart C, as nonattainment for a pollutant for which 
the source or modification would be major may be allowed to 
construct only if the stringent conditions set forth below are met. 
These conditions are designed to ensure that the new source's 
emissions will be controlled to the greatest degree possible; that 
more than equivalent offsetting emission reductions (emission 
offsets) will be obtained from existing sources; and that there will 
be progress toward achievement of the NAAQS.
    For each area designated as exceeding a NAAQS (nonattainment 
area) under 40 CFR part 81, subpart C, or for any area designated 
under section 107(d) of the Act as attainment or unclassifiable for 
ozone that is located in an ozone transport region, this 
Interpretative Ruling will be superseded after June 30, 1979 (a) by 
preconstruction review provisions of the revised SIP, if the SIP 
meets the requirements of part D, Title 1, of the Act; or (b) by a 
prohibition on construction under the applicable SIP and section 
110(a)(2)(I) of the Act, if the SIP does not meet the requirements 
of part D. The Ruling will remain in effect to the extent not 
superseded

[[Page 37930]]

under the Act. This prohibition on major new source construction 
does not apply to a source whose permit to construct was applied for 
during a period when the SIP was in compliance with part D, or 
before the deadline for having a revised SIP in effect that 
satisfies part D.
* * * * *

II. Initial Screening Analyses and Determination of Applicable 
Requirements

    A. * * *
    4. (i) * * *
    (a) Any stationary source of air pollutants which emits, or has 
the potential to emit, 100 tons per year or more of a regulated NSR 
pollutant (as defined in paragraph II.A.31 of this Ruling), except 
that lower emissions thresholds shall apply in areas subject to 
subpart 2, subpart 3, or subpart 4 of part D, title I of the Act, 
according to paragraphs II.A.4(i)(a)(1) through (8) of this Ruling.
* * * * *
    (iii) The fugitive emissions of a stationary source shall not be 
included in determining for any of the purposes of this Ruling 
whether it is a major stationary source, unless the source belongs 
to one of the following categories of stationary sources:
* * * * *
    (h) Municipal incinerators capable of charging more than 50 tons 
of refuse per day;
* * * * *
    5. * * *
    (iii) * * *
    (e) * * *
    (1) The source was capable of accommodating before December 21, 
1976, unless such change would be prohibited under any federally 
enforceable permit condition which was established after December 
21, 1976, pursuant to 40 CFR 52.21 or under regulations approved 
pursuant to 40 CFR part 51, subpart I; or
    (2) The source is approved to use under any permit issued under 
this Ruling;
* * * * *
    (f) An increase in the hours of operation or in the production 
rate, unless such change is prohibited under any federally 
enforceable permit condition which was established after December 
21, 1976, pursuant to 40 CFR 52.21 or under regulations approved 
pursuant to 40 CFR part 51, subpart I;
* * * * *
    7. * * *
    (ii) An existing emissions unit is any emissions unit that does 
not meet the requirements in paragraph II.A.7(i) of this Ruling. A 
replacement unit, as defined in paragraph II.A.37 of this Ruling, is 
an existing emissions unit.
* * * * *
    34. Best available control technology (BACT) means an emissions 
limitation (including a visible emissions standard) based on the 
maximum degree of reduction for each regulated NSR pollutant which 
would be emitted from any proposed major stationary source or major 
modification which the reviewing authority, on a case-by-case basis, 
taking into account energy, environmental, and economic impacts and 
other costs, determines is achievable for such source or 
modification through application of production processes or 
available methods, systems, and techniques, including fuel cleaning 
or treatment or innovative fuel combustion techniques for control of 
such pollutant. In no event shall application of best available 
control technology result in emissions of any pollutant which would 
exceed the emissions allowed by any applicable standard under 40 CFR 
part 60, 61, or 63. If the reviewing authority determines that 
technological or economic limitations on the application of 
measurement methodology to a particular emissions unit would make 
the imposition of an emissions standard infeasible, a design, 
equipment, work practice, operational standard, or combination 
thereof, may be prescribed instead to satisfy the requirement for 
the application of BACT. Such standard shall, to the degree 
possible, set forth the emissions reduction achievable by 
implementation of such design, equipment, work practice or 
operation, and shall provide for compliance by means which achieve 
equivalent results.
    35. Prevention of Significant Deterioration (PSD) permit means 
any permit that is issued under a major source preconstruction 
permit program that has been approved by the Administrator and 
incorporated into the plan to implement the requirements of Sec.  
51.166, or under the program in Sec.  52.21 of this chapter.
* * * * *
    37. Replacement unit means an emissions unit for which all the 
criteria listed in paragraphs II.A.37(i) through (iv) of this Ruling 
are met. No creditable emission reductions shall be generated from 
shutting down the existing emissions unit that is replaced.
    (i) The emissions unit is a reconstructed unit within the 
meaning of Sec.  60.15(b)(1) of this chapter, or the emissions unit 
completely takes the place of an existing emissions unit;
    (ii) The emissions unit is identical to or functionally 
equivalent to the replaced emissions unit;
    (iii) The replacement does not alter the basic design parameters 
of the process unit; and
    (iv) The replaced emissions unit is permanently removed from the 
major stationary source, otherwise permanently disabled, or 
permanently barred from operation by a permit that is enforceable as 
a practical matter. If the replaced emissions unit is brought back 
into operation, it shall constitute a new emissions unit.
    B. Review of all sources for emission limitation compliance. The 
reviewing authority must examine each proposed major new source and 
proposed major modification \1\ to determine if such a source will 
meet all applicable emission requirements in the SIP, any applicable 
new source performance standard in part 60 of this chapter, or any 
national emission standard for hazardous air pollutants in part 61 
or 63 of this chapter. If the reviewing authority determines that 
the proposed major new source cannot meet the applicable emission 
requirements, the permit to construct must be denied.
    \1\ Hereafter the term source will be used to denote both any 
source and any modification.
* * * * *
    F. * * *
    (8) Municipal incinerators capable of charging more than 50 tons 
of refuse per day;
* * * * *
    G. Secondary emissions. Secondary emissions need not be 
considered in determining whether the emission rates in section 
II.C. above would be exceeded. However, if a source is subject to 
this Ruling on the basis of the direct emissions from the source, 
the applicable conditions of this Ruling must also be met for 
secondary emissions. However, secondary emissions may be exempt from 
Conditions 1 and 2 of section IV of this Ruling. Also, since EPA's 
authority to perform or require indirect source review relating to 
mobile sources regulated under Title II of the Act (motor vehicles 
and aircraft) has been restricted by statute, consideration of the 
indirect impacts of motor vehicles and aircraft traffic is not 
required under this Ruling.

III. * * *

    B. Sources to which this section applies must meet Conditions 1, 
2, and 4 of section IV.A. of this Ruling.\2\ However, such sources 
may be exempt from Condition 3 of section IV.A. of this Ruling.
    \2\ The discussion in this paragraph is a proposal, but 
represents EPA's interim policy until final rulemaking is completed.
    C. Review of specified sources for air quality impact. For 
stable air pollutants (i.e., SO2, particulate matter and 
CO), the determination of whether a source will cause or contribute 
to a violation of a NAAQS generally should be made on a case-by-case 
basis as of the proposed new source's start-up date using the 
source's allowable emissions in an atmospheric simulation model 
(unless a source will clearly impact on a receptor which exceeds a 
NAAQS).
    For sources of nitrogen oxides, the initial determination of 
whether a source would cause or contribute to a violation of the 
NAAQS for NO2 should be made using an atmospheric 
simulation model assuming all the nitric oxide emitted is oxidized 
to NO2 by the time the plume reaches ground level. The 
initial concentration estimates may be adjusted if adequate data are 
available to account for the expected oxidation rate.
    For ozone, sources of volatile organic compounds, locating 
outside a designated ozone nonattainment area, will be presumed to 
have no significant impact on the designated nonattainment area. If 
ambient monitoring indicates that the area of source location is in 
fact nonattainment, then the source may be permitted under the 
provisions of any State plan adopted pursuant to section 
110(a)(2)(D) of the Act until the area is designated nonattainment 
and a State implementation plan revision is approved. If no State 
plan pursuant to section 110(a)(2)(D) of the Act has been adopted 
and approved, then this Ruling shall apply.
    As noted above, the determination as to whether a source would 
cause or contribute to a violation of a NAAQS should be made as of 
the new source's start-up date.

[[Page 37931]]

Therefore, if a designated nonattainment area is projected to be an 
attainment area as part of an approved SIP control strategy by the 
new source start-up date, offsets would not be required if the new 
source would not cause a new violation.
    D. * * *
    Condition 1. The new source is required to meet a more stringent 
emission limitation\3\ and/or the control of existing sources below 
allowable levels is required so that the source will not cause a 
violation of any NAAQS.
    \3\ If the reviewing authority determines that technological or 
economic limitations on the application of measurement methodology 
to a particular class of sources would make the imposition of an 
enforceable numerical emission standard infeasible, the authority 
may instead prescribe a design, operational, or equipment standard. 
In such cases, the reviewing authority shall make its best estimate 
as to the emission rate that will be achieved and must specify that 
rate in the required submission to EPA (see part V of this Ruling). 
Any permits issued without an enforceable numerical emission 
standard must contain enforceable conditions which assure that the 
design characteristics or equipment will be properly maintained (or 
that the operational conditions will be properly performed) so as to 
continuously achieve the assumed degree of control. Such conditions 
shall be enforceable as emission limitations by private parties 
under section 304. Hereafter, the term emission limitation shall 
also include such design, operational, or equipment standards.
* * * * *

IV. * * *

    A. * * *
    Condition 1. The new source is required to meet an emission 
limitation\4\ which specifies the lowest achievable emission rate 
for such source.
    \4\ If the reviewing authority determines that technological or 
economic limitations on the application of measurement methodology 
to a particular class of sources would make the imposition of an 
enforceable numerical emission standard infeasible, the authority 
may instead prescribe a design, operational or equipment standard. 
In such cases, the reviewing authority shall make its best estimate 
as to the emission rate that will be achieved and must specify that 
rate in the required submission to EPA (see part V of this Ruling). 
Any permits issued without an enforceable numerical emission 
standard must contain enforceable conditions which assure that the 
design characteristics or equipment will be properly maintained (or 
that the operational conditions will be properly performed) so as to 
continuously achieve the assumed degree of control. Such conditions 
shall be enforceable as emission limitations by private parties 
under section 304. Hereafter, the term emission limitation shall 
also include such design, operational, or equipment standards.
* * * * *
    Condition 4. The emission offsets will provide a positive net 
air quality benefit in the affected area (see section IV.D. of this 
Ruling). Atmospheric simulation modeling is not necessary for 
volatile organic compounds and NOX. Fulfillment of 
Condition 3 under section IV.A. of this Ruling and the requirements 
under section IV.D. of this Ruling will be considered adequate to 
meet this condition.
* * * * *
    B. Exemptions from certain conditions. The reviewing authority 
may exempt the following sources from Condition 1 under section 
III.D. of this Ruling or Conditions 3 and 4 under section IV.A. of 
this Ruling:
    (i) * * *
    1. The applicant demonstrates that it made its best efforts to 
obtain sufficient emission offsets to comply with Condition 1 under 
section III.D. of this Ruling or Conditions 3 and 4 under section 
IV.A. of this Ruling and that such efforts were unsuccessful;
* * * * *
    C. * * *
    3. * * *
    (i) Emissions reductions achieved by shutting down an existing 
source or curtailing production or operating hours may be generally 
credited for offsets if they meet the requirements in paragraphs 
IV.C.3.(i)(1) and (2) of this Ruling.
* * * * *
    (ii) Emissions reductions achieved by shutting down an existing 
source or curtailing production or operating hours and that do not 
meet the requirements in paragraphs IV.C.3.(i)(1) and (2) of this 
Ruling may be generally credited only if:
* * * * *
    (2) The applicant can establish that the proposed new source is 
a replacement for the shutdown or curtailed source, and the 
emissions reductions achieved by the shutdown or curtailment met the 
requirements of paragraphs IV.C.3.(i)(1) and (2) of this Ruling.
    4. Credit for VOC substitution. No emission offset credit may be 
allowed for replacing one hydrocarbon compound with another of 
lesser reactivity, except that an emission credit may be allowed for 
the replacement with those compounds listed as having negligible 
photochemical reactivity in Sec.  51.100(s).
    5. ``Banking'' of emission offset credit. For new sources 
obtaining permits by applying offsets after January 16, 1979, the 
reviewing authority may allow offsets that exceed the requirements 
of reasonable progress toward attainment (Condition 3 under 
paragraph IV.A of this Ruling) to be ``banked'' (i.e., saved to 
provide offsets for a source seeking a permit in the future) for use 
under this Ruling. Likewise, the reviewing authority may allow the 
owner of an existing source that reduces its own emissions to bank 
any resulting reductions beyond those required by the SIP for use 
under this Ruling, even if none of the offsets are applied 
immediately to a new source permit. A reviewing authority may allow 
these banked offsets to be used under the preconstruction review 
program required by part D of the Act, as long as these banked 
emissions are identified and accounted for in the SIP control 
strategy. A reviewing authority may not approve the construction of 
a source using banked offsets if the new source would interfere with 
the SIP control strategy or if such use would violate any other 
condition set forth for use of offsets. To preserve banked offsets, 
the reviewing authority should identify them in either a SIP 
revision or a permit, and establish rules as to how and when they 
may be used.
* * * * *
    D. Location of offsetting emissions. The owner or operator of a 
new or modified major stationary source may comply with any offset 
requirement in effect under this Ruling for increased emissions of 
any air pollutant only by obtaining emissions reductions of such air 
pollutant from the same source or other sources in the same 
nonattainment area, except that the reviewing authority may allow 
the owner or operator of a source to obtain such emissions 
reductions in another nonattainment area if the conditions under 
paragraphs IV.D.1 and 2 of this Ruling are met.
* * * * *
    G. * * *
    1. In meeting the emissions offset requirements of Condition 3 
under paragraph IV.A. of this Ruling, the ratio of total actual 
emissions reductions to the emissions increase shall be at least 1:1 
unless an alternative ratio is provided for the applicable 
nonattainment area in paragraphs IV.G.2 through IV.G.4 of this 
Ruling.
* * * * *
    5. Interpollutant offsetting. In meeting the emissions offset 
requirements of paragraph IV.A, Condition 3 of this Ruling, the 
emissions offsets obtained shall be for the same regulated NSR 
pollutant unless interpollutant offsetting is permitted for a 
particular pollutant as specified in this paragraph IV.G.5. The 
offset requirements of paragraph IV.A, Condition 3 of this Ruling 
for direct PM2.5 emissions or emissions of precursors of 
PM2.5 may be satisfied by offsetting reductions of direct 
PM2.5 emissions or emissions of any PM2.5 
precursor identified under paragraph II.A.31 (iii) of this Ruling if 
such offsets comply with an interprecursor trading hierarchy and 
ratio approved by the Administrator.
* * * * *
    H. Additional provisions for emissions of nitrogen oxides in 
ozone transport regions and nonattainment areas. The requirements of 
this Ruling applicable to major stationary sources and major 
modifications of volatile organic compounds shall apply to nitrogen 
oxides emissions from major stationary sources and major 
modifications of nitrogen oxides in an ozone transport region or in 
any ozone nonattainment area, except in ozone nonattainment areas 
where the Administrator has granted a NOX waiver applying 
the standards set forth under section 182(f) of the Act and the 
waiver continues to apply
    I. * * *
    2. For any major stationary source with a PAL for a regulated 
NSR pollutant, the major stationary source shall comply with 
requirements under paragraph IV.K of this Ruling.
    J. * * *
    6. * * *
    (ii) A projected actual emissions increase that, added to the 
amount of emissions excluded under paragraph II.A.24(ii)(c) of

[[Page 37932]]

this Ruling, sums to at least 50 percent of the amount that is a 
``significant emissions increase,'' as defined under paragraph 
II.A.23 of this Ruling (without reference to the amount that is a 
significant net emissions increase), for the regulated NSR 
pollutant. For a project for which a reasonable possibility occurs 
only within the meaning of paragraph IV.J.6(ii) of this Ruling, and 
not also within the meaning of paragraph IV.J.6(i) of this Ruling, 
then provisions in paragraphs IV.J.2 through IV.J.5 of this Ruling 
do not apply to the project.
* * * * *
    K. * * *
    5. Public participation requirement for PALs. PALs for existing 
major stationary sources shall be established, renewed, or increased 
through a procedure that is consistent with Sec. Sec.  51.160 and 
51.161. This includes the requirement that the reviewing authority 
provide the public with notice of the proposed approval of a PAL 
permit and at least a 30-day period for submittal of public comment. 
The reviewing authority must address all material comments before 
taking final action on the permit.
* * * * *
    14. Reporting and notification requirements. The owner or 
operator shall submit semi-annual monitoring reports and prompt 
deviation reports to the reviewing authority in accordance with the 
applicable title V operating permit program. The reports shall meet 
the requirements in paragraphs IV.K.14(i) through (iii) of this 
Ruling.
* * * * *
    V. * * *
    A. Source initiated emission offsets. A source may propose 
emission offsets which involve:
    (1) Reductions from sources controlled by the source owner 
(internal emission offsets); and/or (2) reductions from neighboring 
sources (external emission offsets). The source does not have to 
investigate all possible emission offsets. As long as the emission 
offsets obtained represent reasonable progress toward attainment, 
they will be acceptable. It is the reviewing authority's 
responsibility to assure that the emission offsets will be as 
effective as proposed by the source. An internal emission offset 
will be considered enforceable if it is made a SIP requirement by 
inclusion as a condition of the new source permit and the permit is 
forwarded to the appropriate EPA Regional Office.\7\ An external 
emission offset will not be enforceable unless the affected 
source(s) providing the emission reductions is subject to a new SIP 
requirement to ensure that its emissions will be reduced by a 
specified amount in a specified time. Thus, if the source(s) 
providing the emission reductions does not obtain the necessary 
reduction, it will be in violation of a SIP requirement and subject 
to enforcement action by EPA, the State, and/or private parties.
    \7\ The emission offset will, therefore, be enforceable by EPA 
under section 113 of the Act as an applicable SIP requirement and 
will be enforceable by private parties under section 304 of the Act 
as an emission limitation.
    The form of the SIP revision may be a State or local regulation, 
operating permit condition, consent or enforcement order, or any 
other mechanism available to the State that is enforceable under the 
Clean Air Act. If a SIP revision is required, the public hearing on 
the revision may be substituted for the normal public comment 
procedure required for all major sources under Sec.  51.102. The 
formal publication of the SIP revision approval in the Federal 
Register need not appear before the source may proceed with 
construction. To minimize uncertainty that may be caused by these 
procedures, EPA will, if requested by the State, propose a SIP 
revision for public comment in the Federal Register concurrently 
with the State public hearing process. Of course, any major change 
in the final permit/SIP revision submitted by the State may require 
a reproposal by EPA.
* * * * *

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

0
5. The authority citation for part 52 continues to read as follows:

    Authority: 42 U.S.C. 7401, et seq.

Subpart A--General Provisions

0
6. Amend Sec.  52.21 by:
0
a. Revising paragraphs (a)(2)(iv)(a) and (f);
0
c. Revising paragraphs (b)(1)(i)(a) through (c);
0
d. Revising paragraphs (b)(1)(iii)(h) and (z);
0
e. Revising paragraphs (b)(2)(iii)(a) and (b);
0
f. Revising paragraphs (b)(2)(iii)(e)(1) and (f);
0
g. Removing and reserving paragraph (b)(3)(iii)(b);
0
h. Revising paragraph (b)(3)(vi)(c);
0
i. Revising paragraph (b)(12);
0
j. Revising paragraph (b)(23)(ii);
0
k. Revising paragraphs (b)(33)(i) through (iv);
0
l. Revising paragraph (b)(41)(ii)(c);
0
m. Revising paragraph (b)(48)(i)(c);
0
n. Revising paragraph (b)(48)(ii)(d);
0
o. Revising paragraphs (b)(49)(i), (b)(49)(ii) introductory text, 
(b)(49)(ii)(a), and (b)(49)(iii);
0
p. Revising paragraph (b)(49)(iv)(b);
0
q. Revising paragraphs (b)(51);
0
r. Removing paragraphs (b)(55) through (58);
0
s. Revising paragraph (g)(4) introductory text;
0
t. Removing and reserving paragraphs (i)(1)(i) through (v);
0
u. Revising paragraph (i)(1)(vii)(h);
0
v. Removing paragraphs (i)(1)(ix) and (x);
0
w. Removing and reserving paragraphs (i)(6) through (12);
0
x. Revising paragraph (j)(1);
0
y. Revising paragraph (m)(1)(i)(a);
0
z. Removing and reserving paragraphs (m)(1)(v), (vii), and (viii);
0
aa. Revising paragraph (n)(1) introductory text;
0
bb. Revising paragraphs (p)(5) introductory text, (p)(6) and (7), and 
(p)(8) introductory text;
0
cc. Revising paragraph (r)(4);
0
dd. Revising paragraphs (u)(2)(ii) and (u)(3);
0
ee. Revising paragraph (w)(1); and
0
ff. Removing paragraph (cc).
    The revisions read as follows: Sec.  52.21 Prevention of 
significant deterioration of air quality.
    (a) * * *
    (2) * * *
    (iv) * * *
    (a) Except as otherwise provided in paragraph (a)(2)(v) of this 
section, and consistent with the definition of major modification 
contained in paragraph (b)(2) of this section, a project is a major 
modification for a regulated NSR pollutant if it causes two types of 
emissions increases--a significant emissions increase (as defined in 
paragraph (b)(40) section) and a significant net emissions increase (as 
defined in paragraphs (b)(3) and (23) of this section). The project is 
not a major modification if it does not cause a significant emissions 
increase. If the project causes a significant emissions increase, then 
the project is a major modification only if it also results in a 
significant net emissions increase.
* * * * *
    (f) Hybrid test for projects that involve multiple types of 
emissions units. A significant emissions increase of a regulated NSR 
pollutant is projected to occur if the sum of the difference for all 
emissions units, using the method specified in paragraphs (a)(2)(iv)(c) 
and (d) of this section as applicable with respect to each emissions 
unit, equals or exceeds the significant amount for that pollutant (as 
defined in paragraph (b)(23) of this section).
* * * * *
    (b) * * *
    (1)(i) * * *
    (a) Any of the following stationary sources of air pollutants which 
emits, or has the potential to emit, 100 tons per year or more of any 
regulated NSR pollutant: Fossil fuel-fired steam electric plants of 
more than 250 million British thermal units per hour heat input, coal 
cleaning plants (with thermal dryers), kraft pulp mills, portland 
cement plants, primary zinc smelters, iron and steel mill plants, 
primary aluminum ore reduction plants (with thermal dryers), primary 
copper smelters, municipal incinerators capable of charging more than 
50 tons of refuse per day,

[[Page 37933]]

hydrofluoric, sulfuric, and nitric acid plants, petroleum refineries, 
lime plants, phosphate rock processing plants, coke oven batteries, 
sulfur recovery plants, carbon black plants (furnace process), primary 
lead smelters, fuel conversion plants, sintering plants, secondary 
metal production plants, chemical process plants (which does not 
include ethanol production facilities that produce ethanol by natural 
fermentation included in NAICS codes 325193 or 312140), fossil-fuel 
boilers (or combinations thereof) totaling more than 250 million 
British thermal units per hour heat input, petroleum storage and 
transfer units with a total storage capacity exceeding 300,000 barrels, 
taconite ore processing plants, glass fiber processing plants, and 
charcoal production plants;
    (b) Notwithstanding the stationary source size specified in 
paragraph (b)(1)(i)(a) of this section, any stationary source which 
emits, or has the potential to emit, 250 tons per year or more of a 
regulated NSR pollutant; or
    (c) Any physical change that would occur at a stationary source not 
otherwise qualifying under paragraph (b)(1) of this section as a major 
stationary source, if the change would constitute a major stationary 
source by itself.
* * * * *
    (iii) * * *
    (h) Municipal incinerators capable of charging more than 50 tons of 
refuse per day;
* * * * *
    (z) Fossil fuel-fired steam electric plants of more than 250 
million British thermal units per hour heat input, and
* * * * *
    (2) * * *
    (iii) * * *
    (a) Routine maintenance, repair and replacement;
    (b) Use of an alternative fuel or raw material by reason of an 
order under sections 2(a) and (b) of the Energy Supply and 
Environmental Coordination Act of 1974 (or any superseding legislation) 
or by reason of a natural gas curtailment plan pursuant to the Federal 
Power Act;
* * * * *
    (e) * * *
    (1) The source was capable of accommodating before January 6, 1975, 
unless such change would be prohibited under any federally enforceable 
permit condition which was established after January 6, 1975, pursuant 
to 40 CFR 52.21 or under regulations approved pursuant to 40 CFR part 
51, subpart I; or
* * * * *
    (f) An increase in the hours of operation or in the production 
rate, unless such change would be prohibited under any federally 
enforceable permit condition which was established after January 6, 
1975, pursuant to 40 CFR 52.21 or under regulations approved pursuant 
to 40 CFR part 51, subpart I.
* * * * *
    (vi) * * *
    (c) It has approximately the same qualitative significance for 
public health and welfare as that attributed to the increase from the 
particular change.
* * * * *
    (12) Best available control technology means an emissions 
limitation (including a visible emission standard) based on the maximum 
degree of reduction for each pollutant subject to regulation under the 
Act which would be emitted from any proposed major stationary source or 
major modification which the Administrator, on a case-by-case basis, 
taking into account energy, environmental, and economic impacts and 
other costs, determines is achievable for such source or modification 
through application of production processes or available methods, 
systems, and techniques, including fuel cleaning or treatment or 
innovative fuel combustion techniques for control of such pollutant. In 
no event shall application of best available control technology result 
in emissions of any pollutant which would exceed the emissions allowed 
by any applicable standard under 40 CFR part 60, 61, or 63. If the 
Administrator determines that technological or economic limitations on 
the application of measurement methodology to a particular emissions 
unit would make the imposition of an emissions standard infeasible, a 
design, equipment, work practice, operational standard, or combination 
thereof, may be prescribed instead to satisfy the requirement for the 
application of best available control technology. Such standard shall, 
to the degree possible, set forth the emissions reduction achievable by 
implementation of such design, equipment, work practice or operation, 
and shall provide for compliance by means which achieve equivalent 
results.
* * * * *
    (23) * * *
    (ii) Significant means, in reference to a net emissions increase or 
the potential of a source to emit a regulated NSR pollutant that 
paragraph (b)(23)(i) of this section does not list, any emissions rate.
* * * * *
    (33) * * *
    (i) The emissions unit is a reconstructed unit within the meaning 
of Sec.  60.15(b)(1) of this chapter, or the emissions unit completely 
takes the place of an existing emissions unit;
    (ii) The emissions unit is identical to or functionally equivalent 
to the replaced emissions unit;
    (iii) The replacement does not alter the basic design parameters of 
the process unit; and
    (iv) The replaced emissions unit is permanently removed from the 
major stationary source, otherwise permanently disabled, or permanently 
barred from operation by a permit that is enforceable as a practical 
matter. If the replaced emissions unit is brought back into operation, 
it shall constitute a new emissions unit.
* * * * *
    (41) * * *
    (ii) * * *
    (c) Shall exclude, in calculating any increase in emissions that 
results from the particular project, that portion of the unit's 
emissions following the project that an existing unit could have 
accommodated during the consecutive 24-month period used to establish 
the baseline actual emissions under paragraph (b)(48) of this section 
and that are also unrelated to the particular project, including any 
increased utilization due to product demand growth; or
* * * * *
    (48) * * *
    (i) * * *
    (c) For a regulated NSR pollutant, when a project involves multiple 
emissions units, only one consecutive 24-month period must be used to 
determine the baseline actual emissions for the emissions units being 
changed. A different consecutive 24-month period can be used for each 
regulated pollutant.
* * * * *
    (ii) * * *
    (d) For a regulated NSR pollutant, when a project involves multiple 
emissions units, only one consecutive 24-month period must be used to 
determine the baseline actual emissions for all the emissions units 
being changed. A different consecutive 24-month period can be used for 
each regulated NSR pollutant.
* * * * *
    (49) * * *
    (i) Greenhouse gases (GHGs), the air pollutant defined in Sec.  
86.1818-12(a) of this chapter as the aggregate group of six greenhouse 
gases: Carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, 
perfluorocarbons, and sulfur hexafluoride, shall not be subject to 
regulation except as provided in paragraph (b)(49)(iv) of this section

[[Page 37934]]

and shall not be subject to regulation if the stationary source 
maintains its total source-wide emissions below the GHG PAL level, 
meets the requirements in paragraphs (aa)(1) through (15) of this 
section, and complies with the PAL permit containing the GHG PAL.
    (ii) For purposes of paragraphs (b)(49)(iii) through (iv) of this 
section, the term tpy CO2 equivalent emissions 
(CO2e) shall represent an amount of GHGs emitted, and shall 
be computed as follows:
    (a) Multiplying the mass amount of emissions (tpy), for each of the 
six greenhouse gases in the pollutant GHGs, by the gas's associated 
global warming potential published at Table A-1 to subpart A of part 98 
of this chapter--Global Warming Potentials.
* * * * *
    (iii) The term emissions increase as used in paragraph (b)(49)(iv) 
of this section shall mean that both a significant emissions increase 
(as calculated using the procedures in paragraph (a)(2)(iv) of this 
section) and a significant net emissions increase (as defined in 
paragraphs (b)(3) and (23) of this section) occur. For the pollutant 
GHGs, an emissions increase shall be based on tpy CO2e, and 
shall be calculated assuming the pollutant GHGs is a regulated NSR 
pollutant and ``significant'' is defined as 75,000 tpy CO2e 
instead of applying the value in paragraph (b)(23)(ii) of this section.
    (iv) * * *
    (b) The stationary source is an existing major stationary source 
for a regulated NSR pollutant that is not GHGs, and also will have an 
emissions increase of a regulated NSR pollutant, and an emissions 
increase of 75,000 tpy CO2e or more.
* * * * *
    (51) Reviewing authority means the State air pollution control 
agency, local agency, other State agency, Indian tribe, or other agency 
authorized by the Administrator to carry out a permit program under 
Sec.  51.165 or Sec.  51.166 of this chapter, or the Administrator in 
the case of EPA-implemented permit programs under this section.
* * * * *
    (g) * * *
    (4) Lands within the exterior boundaries of Indian Reservations may 
be redesignated only by the appropriate Indian Governing Body. The 
appropriate Indian Governing Body may submit to the Administrator a 
proposal to redesignate areas Class I, Class II, or Class III provided 
that:
* * * * *
    (i) * * *
    (1) * * *
    (vii) * * *
    (h) Municipal incinerators capable of charging more than 50 tons of 
refuse per day;
* * * * *
    (j) * * *
    (1) A major stationary source or major modification shall meet each 
applicable emissions limitation under the State Implementation Plan and 
each applicable emissions standard and standard of performance under 40 
CFR part 60, 61, or 63.
* * * * *
    (m) * * *
    (1) * * *
    (i) * * *
    (a) For the source, each pollutant that it would have the potential 
to emit in a significant amount;
* * * * *
    (n) * * *
    (1) With respect to a source or modification to which paragraphs 
(j), (k), (m), and (o) of this section apply, such information shall 
include:
* * * * *
    (p) * * *
    (5) Class I variances. The owner or operator of a proposed source 
or modification may demonstrate to the Federal Land Manager that the 
emissions from such source or modification would have no adverse impact 
on the air quality related values of any such lands (including 
visibility), notwithstanding that the change in air quality resulting 
from emissions from such source or modification would cause or 
contribute to concentrations which would exceed the maximum allowable 
increases for a Class I area. If the Federal Land Manager concurs with 
such demonstration and he so certifies, the State may authorize the 
Administrator, provided that the applicable requirements of this 
section are otherwise met, to issue the permit with such emission 
limitations as may be necessary to assure that emissions of sulfur 
dioxide, PM2.5, PM10, and nitrogen oxides would 
not exceed the following maximum allowable increases over minor source 
baseline concentration for such pollutants:
* * * * *
    (6) Sulfur dioxide variance by Governor with Federal Land Manager's 
concurrence. The owner or operator of a proposed source or modification 
which cannot be approved under paragraph (p)(5) of this section may 
demonstrate to the Governor that the source cannot be constructed by 
reason of any maximum allowable increase for sulfur dioxide for a 
period of 24 hours or less applicable to any Class I area and, in the 
case of Federal mandatory Class I areas, that a variance under this 
clause would not adversely affect the air quality related values of the 
area (including visibility). The Governor, after consideration of the 
Federal Land Manager's recommendation (if any) and subject to his 
concurrence, may, after notice and public hearing, grant a variance 
from such maximum allowable increase. If such variance is granted, the 
Administrator shall issue a permit to such source or modification 
pursuant to the requirements of paragraph (p)(8) of this section 
provided that the applicable requirements of this section are otherwise 
met.
    (7) Variance by the Governor with the President's concurrence. In 
any case where the Governor recommends a variance with which the 
Federal Land Manager does not concur, the recommendations of the 
Governor and the Federal Land Manager shall be transmitted to the 
President. The President may approve the Governor's recommendation if 
he finds that the variance is in the national interest. If the variance 
is approved, the Administrator shall issue a permit pursuant to the 
requirements of paragraph (p)(8) of this section provided that the 
applicable requirements of this section are otherwise met.
    (8) Emission limitations for Presidential or gubernatorial 
variance. In the case of a permit issued pursuant to paragraph (p)(6) 
or (7) of this section, the source or modification shall comply with 
such emission limitations as may be necessary to assure that emissions 
of sulfur dioxide from the source or modification would not (during any 
day on which the otherwise applicable maximum allowable increases are 
exceeded) cause or contribute to concentrations which would exceed the 
following maximum allowable increases over the baseline concentration 
and to assure that such emissions would not cause or contribute to 
concentrations which exceed the otherwise applicable maximum allowable 
increases for periods of exposure of 24 hours or less for more than 18 
days, not necessarily consecutive, during any annual period:
* * * * *
    (r) * * *
    (4) At such time that a particular source or modification becomes a 
major stationary source or major modification solely by virtue of a 
relaxation in any enforceable limitation which was established after 
August 7, 1980, on the capacity of the source or modification otherwise 
to emit a pollutant, such as a restriction on hours of operation, then 
the requirements of paragraphs (j) through (s) of this section shall 
apply to

[[Page 37935]]

the source or modification as though construction had not yet commenced 
on the source or modification.
* * * * *
    (u) * * *
    (2) * * *
    (ii) The delegate agency shall send a copy of any public comment 
notice required under paragraph (q) of this section to the 
Administrator through the appropriate Regional Office.
    (3) In the case of a source or modification which proposes to 
construct in a Class III area, emissions from which would cause or 
contribute to air quality exceeding the maximum allowable increase 
applicable if the area were designated a Class II area, and where no 
standard under section 111 of the Act has been promulgated for such 
source category, the Administrator must approve the determination of 
best available control technology as set forth in the permit.
* * * * *
    (w) * * *
    (1) Any permit issued under this section or a prior version of this 
section shall remain in effect, unless and until it expires under 
paragraph (r)(2) of this section or is rescinded under this paragraph 
(w).
* * * * *
[FR Doc. 2021-13905 Filed 7-16-21; 8:45 am]
BILLING CODE 6560-50-P