Proposed Rule2026-00782
Determination of Attainment by the Attainment Date; 1997 Ozone Standards; California; Coachella Valley
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
January 15, 2026
Issuing agencies
Environmental Protection Agency
Abstract
The Environmental Protection Agency (EPA) is proposing to determine that the Riverside County (Coachella Valley) 1997 ozone Extreme nonattainment area ("Coachella Valley") attained the 1997 ozone national ambient air quality standards (NAAQS) by its June 15, 2025, attainment date. This proposed determination is based on quality- assured and certified ambient air quality monitoring data from 2022 through 2024. We are taking comments on this proposal and plan to follow with a final action.
Full Text
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<title>Federal Register, Volume 91 Issue 10 (Thursday, January 15, 2026)</title>
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[Federal Register Volume 91, Number 10 (Thursday, January 15, 2026)]
[Proposed Rules]
[Pages 1732-1737]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-00782]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R09-OAR-2025-3127; FRL-13098-01-R9]
Determination of Attainment by the Attainment Date; 1997 Ozone
Standards; California; Coachella Valley
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed determination.
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SUMMARY: The Environmental Protection Agency (EPA) is proposing to
determine that the Riverside County (Coachella Valley) 1997 ozone
Extreme nonattainment area (``Coachella Valley'') attained the 1997
ozone national ambient air quality standards (NAAQS) by its June 15,
2025, attainment date. This proposed determination is based on quality-
assured and certified ambient air quality monitoring data from 2022
through 2024. We are taking comments on this proposal and plan to
follow with a final action.
DATES: Comments must be received on or before February 17, 2026.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R09-
OAR-2025-3127 at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. For comments submitted at
<a href="http://Regulations.gov">Regulations.gov</a>, follow the online instructions for submitting
comments. Once submitted, comments cannot be edited or removed from
<a href="http://Regulations.gov">Regulations.gov</a>. The EPA may publish any comment received to its public
docket. Do not submit electronically any
[[Page 1733]]
information you consider to be Confidential Business Information (CBI)
or other information whose disclosure is restricted by statute.
Multimedia submissions (audio, video, etc.) must be accompanied by a
written comment. The written comment is considered the official comment
and should include discussion of all points you wish to make. The EPA
will generally not consider comments or comment contents located
outside of the primary submission (i.e., on the web, cloud, or other
file sharing system). For additional submission methods, please contact
the person identified in the FOR FURTHER INFORMATION CONTACT section.
For the full EPA public comment policy, information about CBI or
multimedia submissions, and general guidance on making effective
comments, please visit <a href="https://www.epa.gov/dockets/commenting-epa-dockets">https://www.epa.gov/dockets/commenting-epa-dockets</a>. 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: Tom Kelly, EPA Region IX, 75 Hawthorne
St., San Francisco, CA 94105; phone: (415) 972-3856; email:
<a href="/cdn-cgi/l/email-protection#1c777970706532687473717d6f6c5c796c7d327b736a"><span class="__cf_email__" data-cfemail="82e9e7eeeefbacf6eaedefe3f1f2c2e7f2e3ace5edf4">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us,''
and ``our'' refer to the EPA.
Table of Contents
I. Background
A. Regulatory Context
B. Coachella Valley 1997 Ozone Designation, Classifications and
SIP Revisions
II. EPA Analysis
A. Applicable Statutory and Regulatory Provisions
B. Determination of Attainment
C. Monitoring Network Considerations
D. Data Considerations
E. Effects of This Proposed Determination
III. Action Summary
IV. Statutory and Executive Order Reviews
I. Background
A. Regulatory Context
The Clean Air Act (CAA or ``Act'') requires the EPA to establish
primary and secondary NAAQS for certain pervasive pollutants that ``may
reasonably be anticipated to endanger public health and welfare.'' \1\
The primary NAAQS is designed to protect public health with an adequate
margin of safety, and the secondary NAAQS is designed to protect public
welfare and the environment. The EPA has set standards for six common
air pollutants, referred to as criteria pollutants, including ozone.
These standards represent the air quality levels an area must meet to
comply with the CAA.
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\1\ CAA section 108(a).
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Ground-level ozone pollution is formed from the reaction of
volatile organic compounds (VOC) and oxides of nitrogen
(NO<INF>X</INF>) in the presence of sunlight.\2\ These two pollutants,
referred to as ozone precursors, are emitted by many types of sources,
including on- and off-road motor vehicles and engines, power plants and
industrial facilities, and smaller area sources such as lawn and garden
equipment and paints.
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\2\ The State of California refers to reactive organic gases
(ROG) rather than VOC in some of its ozone related SIP submissions.
As a practical matter, ROG and VOC refer to the same set of chemical
constituents, and for the sake of simplicity, we refer to this set
of gases as VOC in this determination notification.
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Scientific evidence indicates that adverse public health effects
occur following exposure to ozone, particularly in children and adults
with lung disease. Breathing air containing ozone can reduce lung
function and inflame airways, which can increase respiratory symptoms
and aggravate asthma or other lung diseases.\3\
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\3\ EPA, Health Effects of Ozone Pollution, available at <a href="https://www.epa.gov/ground-levelozone-pollution/health-effects-ozone-pollution">https://www.epa.gov/ground-levelozone-pollution/health-effects-ozone-pollution</a>.
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On July 18, 1997, the EPA revised the primary and secondary NAAQS
for ozone to set the acceptable level of ozone in the ambient air at
0.08 parts per million (ppm), averaged over an 8-hour period.\4\
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\4\ 62 FR 38856 (July 18, 1997). Primary standards provide
public health protection, including protecting the health of
``sensitive'' populations such as asthmatics, children, and the
elderly. Secondary standards provide public welfare protection,
including protection against decreased visibility and damage to
animals, crops, vegetation, and buildings. Since the primary and
secondary standards established in 1997 are set at the same level,
we refer to them herein using the singular ``1997 ozone NAAQS'' or
``1997 ozone standards.''
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The EPA set the 1997 ozone NAAQS over an 8-hour period based on
scientific evidence demonstrating that ozone causes adverse health
effects at lower concentrations and over longer periods of time than
was understood when the pre-existing 1-hour ozone standards were set.
The EPA determined that the 8-hour standards would be more protective
of human health, especially for children and for adults who are active
outdoors, and for individuals with a preexisting respiratory disease,
such as asthma.
In March 2008, the EPA completed another review of the primary and
secondary ozone standards and tightened them further by lowering the
level for both to 0.075 ppm.\5\ The EPA revoked the 1997 ozone NAAQS
effective April 6, 2015; \6\ however, to comply with anti-backsliding
requirements of the Act, areas designated nonattainment at the time
that the 1997 ozone NAAQS was revoked remain subject to certain
requirements based on their classification at the time of revocation.
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\5\ 73 FR 16436 (March 27, 2008). The EPA further strengthened
the primary and secondary eight-hour ozone NAAQS in October 2015
from 0.075 ppm to 0.070 ppm. 80 FR 65291 (October 26, 2015). This
action relates only to the 1997 ozone NAAQS.
\6\ 80 FR 12264 (March 6, 2015).
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The EPA's determination that an area failed to attain by its
attainment date, which is made under CAA section 301 and consistent
with section 181(b)(2), triggers these anti-backsliding requirements.
See South Coast Air Quality Mgmt. Dist. v. EPA, 882 F.3d 1138, 1147
(D.C. Cir. 2018). On October 26, 2015, the EPA again revised the level
of the primary (and secondary) ozone NAAQS once more to 0.70 ppm.
B. Coachella Valley 1997 Ozone Designation, Classifications and SIP
Revisions
Following promulgation of a new or revised NAAQS, the EPA is
required by the CAA to designate areas throughout the nation as
attaining or not attaining the standards. Effective June 15, 2004, we
designated nonattainment areas for the 1997 ozone standards.\7\ The
designations and classifications for the 1997 ozone standards for
California areas are codified at 40 CFR 81.305. In a rule governing
certain facets of implementation of the 1997 ozone standards (the Phase
1 Rule), the EPA classified the Coachella Valley as ``Serious'' for the
1997 ozone standards, with an attainment date no later than June 15,
2013.\8\ This classification applied to areas under the jurisdiction of
the State of California and the areas of Indian country within the
Coachella Valley.
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\7\ 69 FR 23858 (April 30, 2004).
\8\ 69 FR 23858 (April 30, 2004).
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The Coachella Valley includes a part of the Colorado Desert in
Riverside County, California, as well as parts of the adjacent mountain
ranges. For a precise description of the geographic boundaries of the
area, see 40 CFR 81.305. The Coachella Valley is under the jurisdiction
of the South Coast Air Quality Management District (SCAQMD or
``District''). The District and California Air Resources Board (CARB or
``State'') are responsible for adopting and submitting a state
implementation plan (SIP) to attain the 1997 ozone standards for
nonattainment areas in
[[Page 1734]]
their jurisdiction. The District primarily regulates stationary sources
while CARB regulates mobile sources.
On November 28, 2007, CARB requested that the EPA reclassify the
Coachella Valley 1997 ozone nonattainment area from ``Serious'' to
``Severe-15.'' EPA's proposed rulemaking explained that California's
request applied only to areas subject to the jurisdiction of the State
of California.\9\ It further explained that the Tribes of the Coachella
Valley had not requested authority to administer any Clean Air Act
programs in Indian country. In such circumstances, the EPA implements
relevant reclassification provisions of the CAA, and that EPA was
proposing reclassification for the areas of Indian Country, following
notification of Tribal leaders and an invitation for consultation.\10\
The EPA granted the reclassification request from CARB and finalized
the reclassification of areas of Indian country to Severe, effective
June 4, 2010, with an attainment date of not later than June 15,
2019.\11\
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\9\ 74 FR 43654 (August 27, 2009).
\10\ Indian Country within the boundaries of the 1997 ozone
nonattainment area are the Tribal lands of Agua Caliente Band of
Cahuilla Indians of the Augustine Caliente Reservation, the
Augustine Band of Cahuilla Indians, the Cabazon Band of Mission
Indians, the Santa Rosa Band of Cahuilla Indians and the Torress
Martinez Desert Cahuilla Indians and the Twenty-Nine Palms Band of
Mission Indians of California.
\11\ 75 FR 24409 (May 5, 2010).
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On June 12, 2017, the EPA approved District and CARB submittals
addressing many of the Severe nonattainment area planning requirements
under the CAA for Coachella Valley.\12\ On June 11, 2019, the State
requested a reclassification of Coachella Valley from ``Severe-15'' to
``Extreme,'' which the EPA granted with an attainment date of not later
than June 15, 2024.\13\ In a final rule dated September 5, 2025, EPA
granted a one-year extension of the applicable attainment date to June
15, 2025 at the State's request, upon finding the area satisfied the
statutory criteria under CAA section 181(a)(5).\14\
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\12\ 82 FR 26854 (June 12, 2017).
\13\ 84 FR 32841 (July 10, 2019).
\14\ 90 FR 42844 (September 5, 2025).
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As explained in the action reclassifying the area to Extreme
nonattainment, the EPA's reclassification only applied to the portions
of the Coachella Valley subject to the State's jurisdiction, and the
EPA did not reclassify any areas of Indian country within the
boundaries of the nonattainment area. The EPA only reclassifies
nonattainment areas to Extreme nonattainment on a voluntary basis. The
timing of the State's request so close to the Severe nonattainment date
did not allow the EPA sufficient time to consult with the Tribes of the
Coachella Valley on their interest in a reclassification to Extreme
nonattainment; however, the Tribes were notified of the planned action
for part of the Coachella Valley subject to State jurisdiction.\15\
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\15\ 84 FR 32841, 32842 (July 10, 2019).
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On April 16, 2024, the EPA proposed approval of District and CARB
submittals addressing many of the Extreme area planning requirements
under the CAA for Coachella Valley.\16\ On June 12, 2024, the EPA
finalized approval of certain elements of the Extreme area plan,
including the attainment demonstration, but deferred action on the
reasonable further progress demonstration and the vehicle miles
traveled offset demonstration.\17\ On January 21, 2025, EPA finalized
approval of the remaining elements of the plan, the vehicle miles
traveled offset demonstration and the reasonable further progress
demonstration.\18\ The State submitted a CAA 185 fee rule on August 13,
2024, but the EPA has yet to act on that submittal.\19\
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\16\ The proposal, 89 FR 26817 (April 16,2024), did not address
the submittal's reasonably available control technology
demonstration.
\17\ 89 FR 49815 (June 12, 2024).
\18\ 90 FR 6823 (January 21,2025).
\19\ Letter from Steven S. Cliff CARB to Martha Guzman, EPA
Region IX, dated August 9, 2024 and electronically submitted on
August 13, 2024.
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The State submitted a contingency measure for the 1997 ozone NAAQS
as part of the Severe Area attainment Plan,\20\ but the State later
withdrew the measure because it relied on previously implemented
reductions.\21\ The nonattainment area's Extreme Area attainment plan
explained the District's intent to amend SCAQMD Rule 445, ``Wood
Burning Devices,'' to include potential contingency provisions for
Coachella Valley for the 1997 ozone standards.\22\ To date, the EPA has
not received a submittal to address the 1997 ozone contingency measures
requirements of CAA sections 172(c)(9) and 182(c)(9) for the Coachella
Valley.
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\20\ Letter from James N. Goldstene, CARB, to Wayne Nastri, EPA
Region IX, dated 11/28/2007.
\21\ Letter from Richard Corey, CARB, to John Busterud, EPA
Region IX, dated April 28, 2020. In Bahr v. EPA, 836 F.3d 1218,
1235-1237 (9th Cir. 2016), the Ninth Circuit Court of Appeals held
that already-implemented pollution control measures cannot be used
as contingency measures. Instead, contingency measures must be
conditional and prospective, meaning the measures are triggered by
specific events and implemented to achieve emission reductions only
after those events occur.
\22\ ``Final Coachella Valley Extreme Area Plan for the 1997 8-
Hour Ozone Standard,'' South Coast Air Quality Management District,
dated December 2020, and submitted to EPA in a letter from CARB
dated December 29, 2020, p. 6-30.
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II. EPA Analysis
A. Applicable Statutory and Regulatory Provisions
For the revoked 1997 ozone NAAQS, the EPA is required to determine
whether an ozone nonattainment area attained the ozone standard by the
area's attainment date solely for purposes of triggering any applicable
anti-backsliding requirements. For Extreme areas, applicable
requirements triggered upon a finding that an area failed to attain by
the attainment date are nonattainment contingency measures and CAA
section 185 fee programs.\23\ A determination of whether an area's air
quality meets the 1997 ozone NAAQS is generally based on three years of
complete, quality-assured, and certified air quality monitoring data
gathered at established State and Local Air Monitoring Stations
(``SLAMS'') in the area and entered into the EPA's Air Quality System
(AQS) database.\24\ Data from ambient air monitors operated by state/
local agencies in compliance with EPA monitoring requirements must be
submitted to the AQS database. Monitoring agencies annually certify
that these data are accurate to the best of their knowledge.
Accordingly, the EPA relies primarily on data in its AQS database when
determining the attainment status of an area.\25\ All data are reviewed
to determine the area's air quality status in accordance with 40 CFR
part 50, appendix I.
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\23\ 40 CFR 51.1105(d)(2)(iii).
\24\ Generally, a ``complete'' data set for determining
attainment of ozone NAAQS is one that includes three years of data.
There are less stringent data requirements for showing that a
monitor has failed an attainment test and thus has recorded a
violation of the standard.
\25\ 40 CFR 50.15; 40 CFR part 50, appendix I; 40 CFR part 53;
40 CFR part 58, appendices A, C, D, and E.
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Under EPA regulations at 40 CFR 50.10, an area attains the 1997
ozone NAAQS when the 3-year average of the annual fourth-highest daily
maximum 8-hour average ozone monitor concentrations is less than or
equal to 0.08 ppm (i.e., 0.084 ppm when rounding, based on the
truncating conventions in 40 CFR part 50, appendix I). This 3-year
average is referred to as the ``design value.'' When the design value
is greater than 0.084 ppm at any monitor within the area, then the area
is violating the NAAQS.\26\
[[Page 1735]]
The data completeness requirement is met when the average percent of
days with valid ambient monitoring data is greater than or equal to 90
percent and no single year has less than 75 percent data completeness,
as determined under appendix I of 40 CFR part 50.\27\
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\26\ The data handling convention in 40 CFR part 50, appendix I
dictates that concentrations shall be reported in ppm to the third
decimal place, with additional digits to the right being truncated.
Thus, a computed 3-year average ozone concentration of 0.085 ppm is
greater than 0.08 ppm and would exceed the standard, but a design
value of 0.084 is truncated to 0.08 and attains the 1997 ozone
NAAQS.
\27\ 40 CFR part 50, appendix I, section 2.3(b).
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B. Determination of Attainment
Section 179(c) of the CAA requires that within six months following
the applicable attainment date, the EPA shall determine whether an
ozone nonattainment area attained the standard based on the area's
design value as of that date.\28\ This determination, also referred to
as a determination of attainment by the attainment date, is based on
certified data leading up to the attainment date, i.e., in this case,
data for 2022-2024. Section 179(c)(2) of the CAA requires the EPA to
publish the determination in the Federal Register.
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\28\ A determination that an area has attained by the applicable
attainment date does not constitute a redesignation to attainment.
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The EPA is proposing to determine that the Coachella Valley has
attained the 1997 ozone NAAQS by its applicable attainment date; that
is, that the average of the annual fourth-highest daily maximum 8-hour
average ozone concentrations was at or below 0.084 ppm in the three
years leading up to the applicable attainment date. This proposed
determination is based on three years of quality-assured and certified
ambient air quality monitoring data in AQS for the 2022-2024 monitoring
period.
The EPA's proposed determination of attainment is based upon data
that have been collected and quality assured in accordance with 40 CFR
part 58 and recorded in the EPA's AQS database.\29\ As discussed in
section II.D of this document, ambient air quality monitoring data for
the 3-year period preceding the attainment date (i.e., 2022-2024 for
the 1997 ozone NAAQS for the Coachella Valley, based on the applicable
attainment date of June 15, 2025) meet the data completeness
requirements in 40 CFR part 50, appendix I.
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\29\ The EPA maintains the AQS, a database that contains ambient
air pollution data collected by the EPA, state, local, and Tribal
air pollution control agencies. The AQS also contains meteorological
data, descriptive information about each monitoring station
(including its geographic location and its operator) and data
quality assurance/quality control information. The AQS data is used
to (1) assess air quality, (2) assist in attainment/non-attainment
designations, (3) evaluate SIPs for nonattainment areas, (4) perform
modeling for permit review analysis, and (5) prepare reports for
Congress as mandated by the CAA. Access is through the website at
<a href="https://www.epa.gov/aqs">https://www.epa.gov/aqs</a>.
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C. Monitoring Network Considerations
Section 110(a)(2)(B)(i) of the CAA requires states to establish and
operate air monitoring networks to compile data on ambient air quality
for all criteria pollutants. The ambient air monitoring network in the
Coachella Valley includes air monitoring stations that are managed and
operated by SCAQMD. SCAQMD submits annual network plans to the EPA.
These plans document the status of the District's air monitoring
networks, as required under 40 CFR 58.10. The EPA reviews these annual
network plans for compliance with specific requirements in 40 CFR part
58. With respect to ozone, we have found that the annual network plans
submitted by SCAQMD meet the minimum monitoring requirements of 40 CFR
part 58.\30\
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\30\ We have included copies of CARB and SCAQMD's annual network
plans for 2022-2024 in the docket for this action, along with our
reviews of these plans and our associated transmittal
correspondence.
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Finally, the EPA conducts regular Technical Systems Audits (TSAs)
to review and inspect state and local ambient air monitoring programs
to assess compliance with applicable regulations concerning the
collection, analysis, validation, and reporting of ambient air quality
data. As a Primary Quality Assurance Organization (PQAO) in California,
SCAQMD is responsible for overseeing the quality of the data it
collects. For the purposes of this determination, we reviewed the
findings from the EPA's most recent TSA of the SCAQMD ambient air
monitoring program.\31\ The results of this TSA found that the
District's PQAO quality system was functioning well and produced ozone
data suitable for use in regulatory decision-making. Therefore, the
results of the TSA do not preclude the EPA from determining that the
Coachella Valley has attained the 1997 ozone NAAQS.
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\31\ Letter from Matthew Lakin, EPA to Dr. Jason Low, SCAQMD
(Technical Systems Audit), dated June 6, 2025.
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D. Data Considerations
In accordance with 40 CFR 58.15, SCAQMD annually certifies that the
previous year's ambient concentration and quality assurance data are
completely submitted to AQS and that the ambient concentration data are
accurate, taking into consideration the quality assurance findings.\32\
The monitoring sites within the Coachella Valley for calendar years
2022 through 2024 are located in Joshua Tree National Park, Palm
Springs, and Indio. Table 1 of this document summarizes the ozone
monitoring data from the monitoring sites by showing, if available, the
annual 4th highest daily maximum concentrations and design values over
the 2022-2024 period. The monitoring data is representative of the
areas of Indian country as well as land under the jurisdiction of the
State of California.
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\32\ We have included SCAQMD's and CARB's annual data
certifications for 2022, 2023, and 2024 in the docket for this
action.
Table 1--Coachella Valley Monitors With Valid Fourth High 8-Hour Ozone Average Concentrations and Design Values
(ppm) for 2022-2024
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4th Highest daily maximum
AQS site ID Site name Design value --------------------------------------
(2022-2024) 2022 2023 2024
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060650010..................... Joshua Tree National 0.070 0.070 0.071 0.070
Park, Cottonwood
Visitor Center.
060652007..................... Indio-Amistad High Invalid \b\ \a\ N/A \a\ N/A 0.079
School \a\.
060655001..................... Palm Springs-Fire 0.084 0.084 \c\ 0.083 0.087
Station.
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\a\ The former Indio-Jackson station closed April 20, 2022 and SCAQMD relocated the monitoring site to the
nearby Indio-Amistad High School and began monitoring January 1, 2024. EPA approved this relocation on October
29, 2024 after being notified via letter on April 2, 2024, and data from the old and new sites was combined to
form one continuous data record for design value calculations.
\b\ The 2024 design value at the Indio--Amistad High School is invalid due to incomplete data capture in
calendar years 2022 (30%) and 2023 (0%).
\c\ The 2023 design value excludes concurred upon wildfire-driven exceedances of the 1997 ozone NAAQS at the
Palms Springs--Fire Station monitoring site on July 14-15, 2023, under the Exceptional Events Rule.
Source: EPA, AQS Design Value (AMP480), Report Request ID: May 27, 2025.
[[Page 1736]]
Consistent with the requirements contained in 40 CFR part 50, the
EPA has reviewed the quality-assured and certified ozone ambient air
monitoring data for completeness. The EPA reviewed the data as recorded
in AQS for the applicable monitoring period, collected at the
monitoring sites in the Coachella Valley, and has determined that the
data are generally complete, with the exception of the Indio-Amistad
High School monitor. The former Indio-Jackson monitoring site was
closed April 20, 2022, due to loss of the lease and reopened at the
nearby Indio-Amistad High School location on January 1, 2024. SCAQMD
notified the EPA of this closure via letter on April 2, 2024, and
documented it in its 2024 annual network plan. The combined data for
the Indio-Jackson Street and Indio-Amistad monitoring sites had design
values that were 0.003-0.013 ppm lower than the highest design value
site for the previous ten valid design value years (2011-2022) \33\ and
has had design values below the 1997 ozone NAAQS since 2020. In
addition, the 2024 4th highest daily maximum concentration observed at
the Indio-Amistad High School monitoring site was below the level of
the 1997 ozone NAAQS and 0.008 ppm lower than that observed at Palm
Springs-Fire Station.
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\33\ AQS Design Value (AMP480), Report Request ID: 2294814, May
27, 2025.
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The remaining ozone monitoring sites meet the data completeness
requirements of 40 CFR part 50, Appendix I, and, therefore, the data
summarized in table 1 of this document are considered complete for the
purposes of determining if the standard is met. In light of the extent
and reliability of the applicable ozone monitoring network, and the
data collected from that network and summarized in table 1 of this
document, we are proposing to determine that the Coachella Valley
attained the revoked 1997 ozone NAAQS (as defined in 40 CFR part 50,
appendix I) by the applicable attainment date (i.e., June 15, 2025).
E. Effects of This Proposed Determination
A determination of attainment by the attainment date does not have
the effect of redesignating an area to attainment. Redesignation of an
area to attainment requires that an area has met all applicable
requirements of CAA section 110 and part D, and that the area has
submitted, and the EPA has approved, a redesignation request and
maintenance plan.\34\ Therefore, if we finalize this determination as
proposed, Coachella Valley will remain designated nonattainment for the
1997 ozone NAAQS and will retain its current classification of Extreme
for this standard. In addition, a final determination of attainment by
the extended Extreme area attainment date would not apply to Tribal
land, because areas of Indian country in the Coachella Valley
nonattainment area remained classified as Severe nonattainment
following EPA's action on the voluntary reclassification request to
Extreme of state land from CARB and the SCAQMD.\35\
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\34\ Memorandum dated September 4, 1992 from John Calcagni, EPA,
to Regional Air Directors, titled ``Procedures for Processing
Requests to Redesignate Areas to Attainment.''
\35\ 84 FR 32841 (July 10, 2019).
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If we finalize our proposed determination that the Coachella Valley
has attained the 1997 ozone NAAQS by the attainment date, then
attainment contingency measures for the 1997 ozone NAAQS would never be
required to be implemented, regardless of whether the area continued to
attain the NAAQS, and Reasonable Further Progress contingency measures
could not be triggered and would therefore no longer be necessary.\36\
In addition, the Coachella Valley would not collect CAA section 185
fees. A final determination of attainment, however, would not prevent
the EPA from exercising its authority under the CAA to address any
subsequent violations of the NAAQS.
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\36\ See, e.g., 87 FR 42126, 42130 (July 14, 2022). See also 57
FR 13498, 13564 (April 16, 1992) and Memorandum dated May 10, 1995,
from John D. Seitz, EPA, to EPA Regional Air Directors, Regions I-X,
Subject: ``Reasonable Further Progress, Attainment Demonstration,
and Related Requirements for Ozone Nonattainment Areas Meeting the
Ozone National Ambient Air Quality Standard,'' p. 4.
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III. Action Summary
We are proposing to determine that the Coachella Valley has
attained the revoked 1997 ozone NAAQS by its June 15, 2025, attainment
date, based on quality-assured and certified ambient air quality
monitoring data from 2022 through 2024. The EPA is soliciting public
comments on this proposed action, our rationale for the proposed
action, and any other pertinent matters related to the proposed
decision. We will accept comments from the public on this proposal for
the next 30 days and will consider comments before taking final action.
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
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 proposed action:
<bullet> 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);
<bullet> Is not subject to Executive Order 14192 (90 FR 9065,
February 6, 2025) because SIP actions are exempt from review under
Executive Order 12866;
<bullet> Does not impose an information collection burden under the
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
<bullet> 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.);
<bullet> 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);
<bullet> Does not have federalism implications as specified in
Executive Order 13132 (64 FR 43255, August 10, 1999);
<bullet> Is not subject to Executive Order 13045 (62 FR 19885,
April 23, 1997) because it approves a State program;
<bullet> Is not a significant regulatory action subject to
Executive Order 13211 (66 FR 28355, May 22, 2001); and
<bullet> 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 Tribal 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).
[[Page 1737]]
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Nitrogen oxides, Ozone,
Reporting and recordkeeping requirements, Volatile organic compounds.
Dated: January 5, 2026.
Michael Martucci,
Acting Regional Administrator, Region IX.
[FR Doc. 2026-00782 Filed 1-14-26; 8:45 am]
BILLING CODE 6560-50-P
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</html>Indexed from Federal Register on January 15, 2026.
This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.