Air Plan Approval; Arizona; Interstate Transport Requirements for the 2012 Fine Particulate Matter National Ambient Air Quality Standards

[Federal Register Volume 91, Number 73 (Thursday, April 16, 2026)]
[Rules and Regulations]
[Pages 20365-20368]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2026-07400]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2025-0191; FRL-12978-02-R9]

Air Plan Approval; Arizona; Interstate Transport Requirements for
the 2012 Fine Particulate Matter National Ambient Air Quality Standards

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Clean Air Act (CAA) requires each state implementation
plan (SIP) to contain adequate provisions prohibiting emissions that
will significantly contribute to nonattainment or interfere with
maintenance of air quality in other states. The State of Arizona
submitted SIP revisions to the Environmental Protection Agency (EPA) to
address these requirements for the 2012 fine particulate matter
(PM2.5) national ambient air quality standards (NAAQS). The
EPA is finalizing approval of Arizona's SIP submission as meeting the
requirement that the Arizona SIP contains adequate provisions to
prohibit emissions activity, within the State, from emitting air
pollutants in amounts that will significantly contribute to
nonattainment or interfere with maintenance of the 2012
PM2.5 NAAQS in any other state.

DATES: This rule is effective May 18, 2026.

ADDRESSES: The EPA has established a docket for this action under
Docket ID No. EPA-R09-OAR-2025-0191. All documents in the docket are
listed on the https://www.regulations.gov website. Although potentially
listed in the index, some information is not publicly available, e.g.,
Confidential Business Information 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 through https://www.regulations.gov, or please contact the
person identified in the FOR FURTHER INFORMATION CONTACT section for
additional availability information. If you need assistance in a
language other than English or if you are a person with a disability
who needs a reasonable accommodation at no cost to you, please contact
the person identified in the FOR FURTHER INFORMATION CONTACT section.

FOR FURTHER INFORMATION CONTACT: Michael Dorantes, Geographic
Strategies and Modeling Section (AIR 2-2), EPA Region IX, 75 Hawthorne
Street, San Francisco, CA, telephone number: (415) 972-3934, email
address: dorantes.michael@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us,''
and ``our'' refer to the EPA.

Table of Contents

I. Summary of Proposed Action
II. Public Comments and EPA Responses
III. Final Action
IV. Statutory and Executive Order Reviews

I. Summary of Proposed Action

On October 23, 2025, the EPA proposed to approve the SIP revisions
submitted by the State of Arizona on December 11, 2015, and on February
10, 2022, (collectively referred to herein as ``Arizona's 2012
PM2.5 I-SIP submittals'') with respect to the interstate
transport requirements of CAA section 110(a)(2)(D)(i)(I) for the 2012
PM2.5 NAAQS.\1\ Based on our evaluation summarized in our
proposed rulemaking and fully detailed in the accompanying technical
support document, we proposed to find that Arizona's 2012
PM2.5 I-SIP submittals contained adequate provisions to
prohibit any source or other type of emissions activity within the
state from emitting air pollutants in amounts that will significantly
contribute to nonattainment of the 2012 PM2.5 NAAQS in
another state (prong 1) or interfere with maintenance of the 2012
PM2.5 NAAQS in another state (prong 2). Additionally, we
proposed that Arizona's 2012 PM2.5 I-SIP submittals met the
procedural requirements for

[[Page 20366]]

public participation under CAA section 110(a)(2) and 40 CFR 51.102.
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\1\ 90 FR 48502 (October 23, 2025).
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II. Public Comments and EPA Responses

The EPA's proposed action provided a 30-day public comment period
that ended on November 24, 2025. During this period, the EPA received
two comments, one from a private citizen and the other from a private
organization.\2\ The comment submission from the private citizen was
supportive of our proposed approval of the Arizona's 2012
PM2.5 I-SIP submittals with respect to the interstate
transport requirements of CAA section 110(a)(2)(D)(i)(I). This
supportive comment does not require a response. The comment submittal
from the private organization raised several issues in opposition to
our proposed action, so we address each one individually in this
section.
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\2\ Both comments are available in the docket associated with
this rulemaking action at https://www.regulations.gov, docket ID No.
EPA-R09-OAR-2025-0191.
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Comment 1A: First, the commenter references the Regulatory
Flexibility Act (RFA) and Small Business Regulatory Flexibility Act
(SBREFA) and states that the EPA has done a conclusory certification
under 5 U.S.C. 605(b) that the action will not have a significant
economic impact on a substantial number of small entities. They state
that by approving Arizona's 2012 PM2.5 I-SIP submittals,
state control measures relied upon by the EPA and the State in its
submittal become enforceable under Federal law, materially changing the
legal risk for small entities. The commenter states that the EPA should
either prepare an initial Federal regulatory flexibility analysis under
5 U.S.C. 603 or supplement the certification with a broader analysis
than what was provided in the proposal.
Response 1A: The EPA disagrees with this comment. The regulatory
analysis provisions of the RFA are only triggered by a threshold
determination by the Agency that this rule will have a significant
economic impact on a substantial number of small entities. This action
approving Arizona's 2012 PM2.5 I-SIP submittals for the
interstate transport provisions of CAA section 110(a)(2)(D)(i)(I) will
not have a significant economic impact on a substantial number of small
entities under the RFA or SBREFA. This action merely approves Arizona's
weight of evidence analysis that emissions from sources in Arizona will
not significantly contribute to nonattainment or interfere with
maintenance of the 2012 PM2.5 NAAQS in any other state, as
required by the CAA, and does not impose any additional requirements
beyond those already approved into the SIP or otherwise required by
State law. Because the Agency has certified this rule will not have a
significant economic impact, section 603 of the RFA does not apply to
this rulemaking.\3\
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\3\ See 5 U.S.C. 605(b).
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Comment 1B: Citing the Paperwork Reduction Act (PRA) and its
implementing regulations at 5 CFR 1320, the commentor asserts that
Federal agencies must obtain OMB approval for `` `collection of
information' that an agency `conducts or sponsors,' including third-
party or state submissions when a Federal agency requires persons to
obtain, maintain, or disclose information to third parties.'' The
commentor states that many SIP provisions relied upon by Arizona in its
submittal require recordkeeping, plan preparation, and third-party
disclosure, such as maintaining dust control logs onsite for inspectors
and maintaining vendor records. The commentor states that once these
provisions are ``federally approved'' as part of the EPA's action on
Arizona's 2012 PM2.5 I-SIP submittals for interstate
transport, EPA inspectors can require production of these records. The
commentor states that the EPA must clarify whether any SIP
recordkeeping or reporting obligations relied upon in Arizona's
submittal are subject to the requirements of the PRA and if not,
provide a reasoned explanation as to why the recordkeeping and
reporting requirements are not collections of information ``conducted
or sponsored'' by the EPA.
Response 1B: The PRA does not apply to this action. The PRA
generally provides that every Federal agency must obtain Office of
Management and Budget approval before using identical questions to
collect information from 10 or more persons.\4\ The EPA is not
conducting nor sponsoring the collection of information from 10 or more
persons. The EPA is merely approving Arizona's weight of evidence
analysis that emissions from sources in Arizona do not significantly
contribute to nonattainment or interfere with maintenance of the 2012
PM2.5 NAAQS in any other state, as required by the CAA, and
does not impose any additional requirements beyond those already
approved into the SIP or otherwise required by State law.
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\4\ See 44 U.S.C. 3502(3); 3507.
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Comment 1C: Citing 2 U.S.C. 1532, the commentor states that ``the
[Unfunded Mandates Reform Act (UMRA)] requires a written statement for
any rule that includes a `Federal mandate' that may result in
expenditures by State, local, and Tribal governments, in the aggregate,
or by the private sector, of $100 million or more in any one year.''
The commentor asserts that the EPA should either provide an UMRA
analysis that shows expenditures from the EPA's approval of Arizona's
interstate transport plan will not approach the $100 million threshold
or explain why the proposed approval falls outside the UMRA's
definition of a ``Federal mandate.''
Response 1C: The EPA disagrees that this action triggers any
obligations under the UMRA. The EPA has complied by making its own
determination that this rule will not result in expenditures of $100
million or more in any one year, and therefore the Agency does not need
to complete a statement under 2 U.S.C. 1532. As previously stated, this
action merely approves Arizona's weight of evidence analysis that
emissions from sources in Arizona do not significantly contribute to
nonattainment or interfere with maintenance of the 2012
PM2.5 NAAQS in any other state, as required by the CAA. This
action therefore does not impose any Federal mandate on Arizona as that
term is defined in the Act. 2 U.S.C. 1555 (``Notwithstanding section 3
of this Act [2 U.S.C. 1502], for purposes of this title [2 U.S.C. 1551
et seq.] the term ``Federal mandate'' means any provision in statute or
regulation or any Federal court ruling that imposes an enforceable duty
upon State, local, or Tribal governments including a condition of
Federal assistance or a duty arising from participation in a voluntary
Federal program.'').
Comment 1D: The commentor claims that the proposed action ``raises
novel policy and legal issues in the current administrative law
landscape (including post-Loper Bright interpretive standards) and has
broad intergovernmental and economic implications by federalizing
source-level obligations across a large number of small entities in
Arizona.'' The commentor states that the ``novel policy issues'' and
``intergovernmental implications'' of the action warrant review by the
Office of Information and Regulatory Affairs (OIRA), pursuant to
Executive Order (E.O.) 12866. The commentor states that the EPA should
either submit the rulemaking for review by OIRA or explain why
``federalizing SIP obligations'' does not present novel legal or policy
issues and explain why the ``intergovernmental implications'' are not
significant for purposes of E.O. 12866.

[[Page 20367]]

Response 1D: The EPA disagrees that a non-significance analysis is
required under E.O. 12866. The Agency has complied with E.O. 12866 by
determining that this rulemaking is not a significant regulatory action
as defined in E.O. 12866. This action is not ``federalizing SIP
obligations.'' As stated above, the EPA is merely approving Arizona's
weight of evidence analysis that emissions from sources in Arizona do
not significantly contribute to nonattainment or interfere with
maintenance of the 2012 PM2.5 NAAQS in any other state, as
required by the CAA. This action is consistent with the EPA's actions
on other states' plans across the country. Accordingly, this action
does not raise any novel legal or policy issues but merely concludes
that Arizona's 2012 PM2.5 I-SIP submittals meet the
requirements of prongs 1 and 2 of CAA section 110(a)(2)(D)(i)(I).
Comment 1E: The commentor notes that Arizona contains numerous
Tribal lands that can be affected by the downwind transport of air
emissions. Because Tribal governments' air quality interests are at
stake, the commentor asserts that the EPA should clarify whether any
consultation was undertaken or provide a reasoned basis for concluding
that there are no Tribal implications. The commentor states that the
EPA should also revisit E.O. 13132 statement on federalism ``in light
of the practical enforcement and programmatic effects on counties that
administer key SIP measures relied upon in the transport
demonstration.''
Response 1E: The EPA has complied with E.O. 13175 relating to
consultation with Indian tribes by certifying that the action does not
fall under ``policies that have Tribal implications'' as that term is
defined in E.O. 13175. As stated elsewhere, our action merely approves
Arizona's weight of evidence analysis that it does not cause or
contribute to nonattainment or interfere with maintenance in any other
state, including on downwind Tribal lands. The action also does not
incorporate any new rules or control measures into the Arizona SIP for
which there might be federalism implications as defined by E.O. 13132.

III. Final Action

For the reasons set forth in our proposed rulemaking and summarized
herein, the EPA is taking final action to approve Arizona's 2012
PM2.5 I-SIP submittals for compliance with the 2012
PM2.5 NAAQS infrastructure SIP requirements of CAA section
110(a)(2)(D)(i)(I). Specifically, the EPA is finalizing our
determination that the Arizona SIP, through the 2012 PM2.5
I-SIP submittals, contains adequate provisions to ensure that emissions
from sources in Arizona will not significantly contribute to
nonattainment or interfere with the maintenance of the 2012
PM2.5 NAAQS in any other state.

IV. Statutory and Executive Order Reviews

Under the CAA, the Administrator is required to approve a SIP
submission that complies with the provisions of the Act and applicable
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in
reviewing SIP submissions, the EPA's role is to approve state choices,
provided that they meet the criteria of the CAA. Accordingly, this
final action merely approves state law as meeting Federal requirements
and does not impose additional requirements beyond those imposed by
state law. For that reason, this action:
• Is not a significant regulatory action subject to review
by the Office of Management and Budget under Executive Order 12866 (58
FR 51735, October 4, 1993);
• Is not subject to Executive Order 14192 (90 FR 9065,
February 6, 2025) because SIP actions are exempt from review under
Executive Order 12866;
• Does not impose an information collection burden under the
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
• Is certified as not having a significant economic impact
on a substantial number of small entities under the Regulatory
Flexibility Act (5 U.S.C. 601 et seq.);
• Does not contain any unfunded mandate or significantly or
uniquely affect small governments, as described in the Unfunded
Mandates Reform Act of 1995 (Pub. L. 104-4);
• Does not have federalism implications as specified in
Executive Order 13132 (64 FR 43255, August 10, 1999);
• Is not subject to Executive Order 13045 (62 FR 19885,
April 23, 1997) because it approves a state program;
• Is not a significant regulatory action subject to
Executive Order 13211 (66 FR 28355, May 22, 2001); and
• Is not subject to requirements of section 12(d) of the
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272
note) because application of those requirements would be inconsistent
with the CAA.
In addition, the SIP is not approved to apply on any Indian
reservation land or in any other area where the EPA or an Indian Tribe
has demonstrated that a Tribe has jurisdiction. In those areas of
Indian country, the rule does not have Tribal implications and will not
impose substantial direct costs on Tribal governments or preempt Tribal
law as specified by Executive Order 13175 (65 FR 67249, November 9,
2000).
This action is subject to the Congressional Review Act, 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).
Under section 307(b)(1) of the Clean Air Act, petitions for
judicial review of this action must be filed in the United States Court
of Appeals for the appropriate circuit by June 15, 2026. Filing a
petition for reconsideration by the Administrator of this final rule
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 may be filed, and shall not postpone the effectiveness
of such rule or action. This action may not be challenged later in
proceedings to enforce its requirements. (See section 307(b)(2).)

List of Subjects in 40 CFR Part 52

Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Nitrogen dioxide, Ozone,
Particulate matter, Reporting and recordkeeping requirements, Volatile
organic compounds.

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

Dated: April 6, 2026.
Michael Martucci,
Acting Regional Administrator, Region IX.

For the reasons stated in the preamble, EPA amends 40 CFR part 52
as follows:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

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

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

Subpart D--Arizona

0
2. In Sec. 52.120, amend table 1 in paragraph (e) by, under the
heading ``Clean Air Act Section 110(a)(2) State Implementation Plan
Elements (Excluding Part D Elements and Plans)'', adding the entry
``State Implementation Plan Revision: Clean Air Act Section 110(a)(2)
for the 2012 Fine Particulate & 2015 Ozone NAAQS (dated February
2022)'' immediately before the entry for ``Ordinance No. 1993-128,
Section 1, 17.040.190 ``Composition'' Section 6, 17.24.040 ``Reporting
for compliance evaluation'' '' to read as follows:

[[Page 20368]]

Sec. 52.120 Identification of plan

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(e) * * *

Table 1--EPA-Approved Non-Regulatory and Quasi-Regulatory Measures
[Excluding certain resolutions and statutes, which are listed in Tables 2 and 3, respectively] \1\
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Applicable geographic
Name of SIP provision or nonattainment area State submittal date EPA approval Explanation
or title/subject date
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* * * * * * *
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The State of Arizona Air Pollution Control Implementation Plan
Clean Air Act Section 110(a)(2) State Implementation Plan Elements (Excluding Part D Elements and Plans)
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* * * * * * *
State Implementation Plan State-wide........... February 10, 2022....... 4/16/2026, 91 Adopted by the
Revision: Clean Air Act FR [INSERT Arizona
Section 110(a)(2) for the FEDERAL Department of
2012 Fine Particulate & 2015 REGISTER PAGE Environmental
Ozone NAAQS (dated February WHERE THE Quality on
2022). DOCUMENT February 10,
BEGINS]. 2022.
As of 4/16/2026
EPA has
approved all
elements of
the submittal
addressing
requirements
for the 2012
PM2.5 NAAQS.

* * * * * * *
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\1\ Table 1 is divided into three parts: Clean Air Act Section 110(a)(2) State Implementation Plan Elements
(excluding Part D Elements and Plans), Part D Elements and Plans (other than for the Metropolitan Phoenix or
Tucson Areas), and Part D Elements and Plans for the Metropolitan Phoenix and Tucson Areas.

* * * * *
[FR Doc. 2026-07400 Filed 4-15-26; 8:45 am]
BILLING CODE 6560-50-P

Air Plan Approval; Arizona; Interstate Transport Requirements for the 2012 Fine Particulate Matter National Ambient Air Quality Standards

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