Proposed Rule2025-09999
Determination of Attainment by the Attainment Date; California; Mariposa County; 2015 8-Hour Ozone National Ambient Air Quality Standards
Primary source
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Published
June 3, 2025
Issuing agencies
Environmental Protection Agency
Abstract
The Environmental Protection Agency (EPA) is proposing to determine that the Mariposa County nonattainment area in California ("Mariposa area"), classified as "Moderate" for the 2015 ozone national ambient air quality standards (NAAQS or "standard"), attained the 2015 ozone NAAQS by the August 3, 2024 attainment date. Our proposed determination of attainment is based upon the exclusion of exceedances of the 2015 ozone NAAQS that occurred on multiple days in 2021 and 2022, because the exceedances are due to exceptional events. This action, if finalized as proposed, will fulfill the EPA's statutory obligation to determine whether the Mariposa area attained the NAAQS by the August 3, 2024 attainment date.
Full Text
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<title>Federal Register, Volume 90 Issue 105 (Tuesday, June 3, 2025)</title>
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[Federal Register Volume 90, Number 105 (Tuesday, June 3, 2025)]
[Proposed Rules]
[Pages 23501-23505]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2025-09999]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R09-OAR-2025-0084; FRL-12611-01-R9]
Determination of Attainment by the Attainment Date; California;
Mariposa County; 2015 8-Hour Ozone National Ambient Air Quality
Standards
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The Environmental Protection Agency (EPA) is proposing to
determine that the Mariposa County nonattainment area in California
(``Mariposa area''), classified as ``Moderate'' for the 2015 ozone
national ambient air quality standards (NAAQS or ``standard''),
attained the 2015 ozone NAAQS by the August 3, 2024 attainment date.
Our proposed determination of attainment is based upon the exclusion of
exceedances of the 2015 ozone NAAQS that occurred on multiple days in
2021 and 2022, because the exceedances are due to exceptional events.
This action, if finalized as proposed, will fulfill the EPA's statutory
obligation to determine whether the Mariposa area attained the NAAQS by
the August 3, 2024 attainment date.
DATES: Comments must be received by July 3, 2025.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R09-
OAR-2025-0084 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 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 disabilities
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: Roxana Sierra-Hern[aacute]ndez, Air
Planning Office (AIR-2), EPA Region IX, 75 Hawthorne Street, San
Francisco, CA 94105. By phone at (213) 244-1891, or by email at
<a href="/cdn-cgi/l/email-protection#590a303c2b2b38313c2b3738373d3c23772b3621383738193c2938773e362f"><span class="__cf_email__" data-cfemail="1c4f75796e6e7d74796e727d72787966326e73647d727d5c796c7d327b736a">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us,''
and ``our'' refer to the EPA.
Table of Contents
I. Background
A. Statutory and Regulatory Background
B. Mariposa Area Designation for the 2015 Ozone NAAQS
II. EPA Analysis
A. Applicable Statutory and Regulatory Provisions
B. Proposed Determination of Attainment by the Attainment Date
C. Monitoring Network Considerations
D. Data Considerations
E. Effects of This Proposal
III. Summary of Proposal
IV. Statutory and Executive Order Reviews
I. Background
A. Statutory and Regulatory Background
Under section 109 of the Clean Air Act (CAA or ``the Act''), the
EPA promulgates NAAQS for pervasive air pollutants, such as ozone. The
NAAQS are concentration limits the EPA has determined to be requisite
to protect public health and welfare.
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.\1\ 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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\1\ The State of California refers to reactive organic gases
(ROG) 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 proposed rulemaking.
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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.\2\
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\2\ ``Fact Sheet--2008 Final Revisions to the National Ambient
Air Quality Standards for Ozone,'' dated March 2008.
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The EPA has previously promulgated NAAQS for ozone in 1979, 1997,
and 2008.\3\ In 2015, the EPA revised the NAAQS to 0.070 parts per
million (ppm) (``2015 ozone NAAQS'') to replace the 2008 ozone NAAQS of
0.075 ppm.\4\ Most recently, in December 2020, the EPA finalized review
of the ozone NAAQS, retaining the form and level of the standards. As
such, no ozone area designations were triggered under the CAA, and
therefore, no nonattainment areas were designated and no new
requirements were triggered.\5\
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\3\ 44 FR 8202 (February 8, 1979), 62 FR 38856 (July 18, 1997),
and 73 FR 16436 (March 27, 2008).
\4\ 80 FR 65292 (October 26, 2015).
\5\ 85 FR 87256 (December 31, 2020).
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Following promulgation of a new or revised NAAQS, the EPA is
required by CAA section 107(d) to designate areas throughout the nation
as either attaining or not attaining the standards. The EPA
[[Page 23502]]
must designate an area as nonattainment if it is violating a standard
or if it has sources contributing to a violation of a standard in a
nearby area. The EPA makes designations and classifications
individually for each area and each standard. For ozone standards, the
EPA classifies nonattainment areas as ``Marginal,'' ``Moderate,''
``Serious,'' ``Severe,'' or ``Extreme,'' depending upon ambient air
monitoring data calculated as an ozone design value for the area at the
time of designation.\6\ An ozone nonattainment area with a higher
classification is subject to a greater number of, and more stringent,
CAA planning and control requirements than lower classification areas,
but the state is provided more time to attain the NAAQS.\7\
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\6\ See CAA section 181(a)(1).
\7\ See generally, subpart 2 of part D of title I of the CAA.
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B. Mariposa Area Designation for the 2015 Ozone NAAQS
The Mariposa area is located in the southern portion of the Sierra
Nevada Mountain range of the State of California, and its boundaries
align with Mariposa County boundaries.\8\
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\8\ See 40 CFR 81.305.
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Effective August 3, 2018, the EPA designated the Mariposa area as
nonattainment for the 2015 ozone NAAQS and classified the area as
Marginal.\9\ Areas classified as Marginal must attain the NAAQS within
3 years of the effective date of the nonattainment designation.\10\
Following this initial classification as Marginal, the EPA found in
2022 that the area did not attain the 2015 ozone standards by the
Marginal attainment deadline of August 3, 2021.\11\ As a result of our
finding, the area was reclassified by operation of law to Moderate
nonattainment. Moderate nonattainment areas have 6 years to attain the
standard, and the Moderate attainment date for the Mariposa area was
August 3, 2024.\12\
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\9\ 83 FR 25776 (June 4, 2018).
\10\ See CAA section 181(a)(1), 40 CFR 51.1102.
\11\ 87 FR 60897 (October 7, 2022).
\12\ Id.
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II. EPA Analysis
A. Applicable Statutory and Regulatory Provisions
The EPA is required to determine whether areas designated
nonattainment attained the NAAQS by the applicable attainment date, and
to take certain steps for areas that failed to attain.\13\ For the 2015
ozone NAAQS, the determination of attainment or failure to attain is
based on a nonattainment area's design value. Under EPA regulations at
40 CFR part 50, appendix U, the 2015 ozone NAAQS is attained at a site
when the design value (i.e., the 3-year average of the annual fourth
highest daily maximum 8-hour average ambient air quality ozone
concentration) does not exceed 0.070 ppm.\14\
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\13\ CAA section 181(b)(2).
\14\ The data handling convention in Appendix P 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 0.071 ppm is greater
than 0.070 ppm and would exceed the standard, but a design value of
0.0709 is truncated to 0.070 and attains the 2015 ozone NAAQS.
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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 Air Quality System (AQS) database.
Ambient air quality monitoring data for the 3-year period preceding the
attainment date must meet the data completeness requirements in
Appendix U.\15\ The completeness requirements are met for the 3-year
period at a monitoring site if daily maximum 8-hour average
concentrations of ozone are available for at least 90 percent of the
days within the ozone monitoring season, on average, for the 3-year
period, and no single year has less than 75 percent data completeness.
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\15\ See 40 CFR part 50, appendix U, section 4(b).
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B. Proposed Determination of Attainment by the Attainment Date
The EPA is proposing this action to fulfill its statutory
obligation under CAA section 181(b)(2) to determine whether the
Mariposa area attained the ozone standard by its applicable attainment
date. Specifically, we are proposing to determine that the Mariposa
area attained the 2015 ozone NAAQS by the attainment date of August 3,
2024.
We are also proposing to determine that, if we finalize the
proposed determination of attainment by the attainment date for the
Mariposa area, then the requirement for the state to have contingency
measures for failure to attain for the 2015 ozone NAAQS will no longer
apply, because contingency measures would never be needed given the
attainment of the NAAQS by the attainment date (see section II.E of
this document).
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. There are two ozone monitoring sites in
the Mariposa area, Jerseydale and Yosemite NP-Turtleback Dome. The
California Air Resources Board (CARB) operates the Jerseydale ozone
monitoring site between April and October when the site is physically
accessible and peak ozone levels are expected, and the National Park
Service operates the Yosemite NP-Turtleback Dome monitor year-round. As
required under 40 CFR 58.10, CARB submits annual network plans (ANP) to
the EPA documenting the status of monitoring sites and instruments
operating in California, including both ozone monitors in the Mariposa
area. The EPA reviews these ANP for compliance with specific
requirements in 40 CFR part 58. We determined that the ANP submitted by
CARB meet the minimum monitoring requirements of 40 CFR part 58.\16\
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\16\ We have included copies of CARB's ANPs for 2021-2023 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. CARB is the Primary Quality Assurance Organization (PQAO) in
California that is responsible for overseeing the quality of data
collected by local air monitoring organizations. For the purposes of
this determination, we reviewed the findings from the EPA's most recent
TSA of CARB's ambient air monitoring program.\17\ We found that the
CARB PQAO quality system 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 Mariposa area has attained
the 2015 ozone NAAQS.
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\17\ See letter from Matthew Lakin, Director, Air and Radiation
Division, U.S. EPA Region IX, to Edie Chang, Deputy Executive
Officer, CARB, dated March 14, 2024, and enclosure titled
``Technical Systems Audit of the Ambient Air Monitoring Program:
CARB, December 2021 through August 2022.''
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D. Data Considerations
Because the design value is based on three complete calendar years
of data, attainment must occur no later than December 31 of the year
prior to the attainment date. Accordingly, the Mariposa area, with an
attainment date of August 3, 2024, must show attainment by December 31,
2023. Our proposed determination is therefore based upon the 2021-2023
design value, which is based upon complete, quality-assured, and
certified ozone monitoring data from calendar years 2021, 2022, and
2023. The data the EPA is using to
[[Page 23503]]
calculate the 2021-2023 design values can be found in the docket for
this proposed rulemaking.\18\
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\18\ See ``U.S. EPA, Design Value Report (AMP480)'' dated
February 24, 2025.
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1. Determination of Attainment and EPA's Analysis of Relevant Air
Quality Monitoring Data
The EPA evaluated air quality data to determine if the Mariposa
area attained or failed to attain the 2015 ozone NAAQS by the
applicable attainment date. CARB contends that some of the exceedances
or violations of the NAAQS in 2021 and 2022 were due to uncontrollable
wildfire smoke. CARB submitted a request to exclude the affected data
from regulatory decisions on the basis that they are exceptional
events,\19\ and the EPA concurred. Our evaluation of the exceptional
events is described in section II.D.2 of this document and the
technical support document (TSD). The design values, excluding
exceedances due to exceptional events, and completeness requirements
for the 2021-2023 period for the two monitoring sites in the Mariposa
area are summarized in Table 1.
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\19\ CARB, ``Exceptional Events Demonstration for Ozone
Exceedances Mariposa County Wildfire Impacts 2021-2022,'' September
26, 2024.
Table 1--2015 Ozone NAAQS Monitoring Data Summary for the Mariposa Area \a\
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4th Highest daily maximum 8- Percent valid days (data 2021-2023
hour average value (ppm) 2021-2023 completeness) Average
AQS site ID Monitoring site name --------------------------------- Design value --------------------------------- percent
2021 2022 2023 (ppm) \a\ 2021 2022 2023 valid days
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06-043-0003........................ Yosemite NP-Turtleback 0.077 0.067 0.068 0.070 98 100 99 99
Dome.
06-043-0006........................ Jerseydale............ 0.081 0.070 0.060 0.070 92 87 92 90
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\a\ The data shown exclude exceedances due to exceptional events.
Source: EPA, AQS Design Value (AMP 480), Report Request ID: 2265346, February 24, 2025.
As explained in section II.A of this document, the 2015 ozone NAAQS
is met at an ambient monitoring site when the design value for the area
does not exceed 0.070 ppm. The design values in Table 1 of this
document show that the Mariposa area has met the 2015 ozone NAAQS.
Additionally, Table 1 of this document shows that the minimum data
completeness requirements are also met because the average percent of
days with valid ambient monitoring data are at least 90 percent, and no
single year has less than 75 percent data completeness in both
monitoring sites. The design value reports from the EPA's AQS database,
and data certification materials from CARB for the relevant years can
be found in the docket for this proposed rulemaking.
2. Exceptional Events Evaluation
Congress has recognized that it may not be appropriate for the EPA
to use certain monitoring data, collected by the ambient air quality
monitoring network and maintained in the EPA's AQS database, in certain
regulatory determinations. Thus, in 2005, Congress provided the
statutory authority for the exclusion of data influenced by
``exceptional events'' meeting specific criteria by adding section
319(b) to the CAA. To implement this section, on March 22, 2007, the
EPA adopted a final rule, ``Treatment of Data Influenced by Exceptional
Events,'' also known as the Exceptional Events Rule (EER).\20\ On
October 3, 2016, the EPA adopted revisions to this rule.\21\ Under the
EER, the EPA may exclude data showing exceedances and/or violations of
the NAAQS from use in specified regulatory determinations if a state
demonstrates that an exceptional event caused the exceedance or
violation.\22\ Before the EPA can exclude data from these regulatory
determinations, the state must flag the data in the EPA's AQS database,
notify the EPA of the state's intent to submit an exceptional event
demonstration, and, after public notice and opportunity for comment,
submit documentation to the EPA to justify the exclusion. The EPA
considers it and concurs or nonconcurs with the state's demonstration.
If the EPA concurs that the exceedance was due to an exceptional event
covered under the EER, the data is excluded from regulatory
determinations, including from a determination of whether the area
attained a NAAQS by its attainment date.
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\20\ 72 FR 13560 (March 22, 2007).
\21\ 81 FR 68216 (October 3, 2016).
\22\ See 40 CFR 50.1 and 50.14.
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In a submittal dated September 26, 2024,\23\ with an attached
transmittal letter dated September 27, 2024,\24\ CARB provided
documentation for ozone exceedances that occurred on multiple days in
2021 and 2022, and which the State had flagged as due to wildfire
exceptional events. These events occurred during the August 7, 2021,
August 27 through 28, 2021, and September 8 through 9, 2022, time
periods. A full list of days identified as exceptional events at each
monitor is included in Table 2.
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\23\ CARB, ``Exceptional Events Demonstration for Ozone
Exceedances Mariposa County Wildfire Impacts 2021-2022,'' September
26, 2024.
\24\ Letter dated September 27, 2024, from Michael Benjamin,
Division Chief, Air Quality Planning and Science Division, CARB, to
Matthew Lakin, Director, Air and Radiation Division, EPA Region IX.
Table 2--Exceedances and/or Violations due to Exceptional Events in the Mariposa Area for the 2015 Ozone NAAQS
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2015 8-hour avg.
Exceedance date Monitoring site name AQS site ID (ppm)
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August 7, 2021............................. Yosemite NP-Turtleback Dome.. 06-043-0003 0.078
August 27, 2021............................ Yosemite NP-Turtleback Dome.. 06-043-0003 0.079
August 28, 2021............................ Yosemite NP-Turtleback Dome.. 06-043-0003 0.086
September 8, 2022.......................... Jerseydale................... 06-043-0006 0.079
September 8, 2022.......................... Yosemite NP-Turtleback Dome.. 06-043-0003 0.068
September 9, 2022.......................... Jerseydale................... 06-043-0006 0.081
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September 9, 2022.......................... Yosemite NP-Turtleback Dome.. 06-043-0003 0.070
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The EPA reviewed the documentation submitted by the State and
concurred with CARB's determinations that the exceedances and/or
violations identified by CARB in 2021 and 2022 were caused by wildfire
exceptional events, and that these exceedances and/or violations meet
the criteria for exclusion from regulatory determinations under the
EER. Accordingly, the EPA concurred with the exclusion flags for the
days flagged in 2021 and 2022 for these areas and is excluding the
monitored exceedances or violations associated with these exceptional
events from use in evaluation of whether the Mariposa area has attained
the 2015 ozone NAAQS by the attainment date in accordance with CAA
section 181(b)(2)(A). The TSD in the docket contains more information
summarizing the EER requirements, the exceptional events, and the EPA's
review process.
A concurrence letter notifying CARB of our decision was sent on
February 19, 2025.\25\ Included with the letter was the TSD setting
forth in detail the bases for the EPA's concurrences.\26\
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\25\ See letter dated February 19, 2025, from Matthew Lakin,
Director, Air and Radiation Division, EPA Region IX, to Michael
Benjamin, Division Chief, Air Quality Planning and Science Division,
CARB.
\26\ EPA, ``Enclosure: Technical Support Document for EPA
Concurrence on Ozone Exceedances Measured in Mariposa County, CA on
August 2, 2021, August 27-28, 2021, and September 8-9, 2022, as
Exceptional Events.''
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Because the demonstration meets the criteria of the EER, the EPA is
proposing to exclude from regulatory consideration data showing
exceedances or violations due to exceptional events at the monitoring
sites in the Mariposa area on August 7, 2021, August 27 through 28,
2021, and September 8 through 9, 2022.
E. Effects of This Proposal
1. Designation and Classification
If the EPA finalizes this proposed determination, the Mariposa area
will remain designated nonattainment and will retain its current
classification. 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.\27\
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\27\ Memorandum dated September 4, 1992, from John Calcagni,
Director, Air Quality Management Division, EPA, to Regional Air
Directors, Subject: ``Procedures for Processing Requests to
Redesignate Areas to Attainment.''
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2. Contingency Measures
Based on our proposed finding of attainment by the applicable
attainment date, we are also proposing to find that the CAA section
172(c)(9) requirement for a state implementation plan (``SIP'') to
include contingency measures to be implemented in the event the area
fails to attain (``attainment contingency measures'') or fails to
achieve reasonable further progress (``RFP contingency measures'') will
no longer apply to the Mariposa area for purposes of the 2015 ozone
NAAQS.
Under CAA section 172(c)(9), attainment contingency measures must
be implemented only if the area fails to attain by the attainment date.
Therefore, if we finalize the determination that the Mariposa area has
attained the 2015 ozone standard by the applicable attainment date,
then attainment contingency measures for this NAAQS would never be
required to be implemented, regardless of whether the area continues to
attain the NAAQS.\28\ This proposed finding will not prevent the EPA,
in the event that the Mariposa area subsequently violates the NAAQS,
from exercising its authority under the CAA to address violations of
the NAAQS.\29\
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\28\ See Bahr v. Regan, 6 F.4th 1059, 1084 (9th Cir. 2021).
\29\ See id. at 1085.
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Additionally, the RFP contingency measure requirement would no
longer apply to the Mariposa area for the 2015 ozone NAAQS, for the
reasons that follow. The purpose of the RFP requirements under the CAA
is to ``ensur[e] attainment of the applicable [NAAQS] by the applicable
date.'' \30\ Consistent with this purpose, under CAA section 182(g),
ozone nonattainment areas classified Serious or higher are required to
meet RFP emission reduction ``milestones'' and to demonstrate
compliance with those milestones, except when the milestone coincides
with the attainment date and the standard has been attained.\31\ This
specific statutory exemption from milestone compliance demonstration
submittals for areas that attained by the attainment date indicates
that Congress intended that a finding that an area attained the
standard--the finding made in a determination of attainment by the
attainment date--would serve as a demonstration that RFP requirements
for the area have been met. In other words, if a Serious or above area
has attained the NAAQS by the attainment date, the RFP milestones have
been sufficiently achieved. Accordingly, such a finding would also
indicate that RFP contingency measures could not be triggered and are
therefore no longer necessary.
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\30\ CAA section 171(1).
\31\ CAA section 182(g)(2).
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In the case of Moderate areas, there are no RFP milestone
compliance demonstration requirements.\32\ Accordingly, the EPA's long-
standing interpretation is that RFP contingency measures for Moderate
areas would be triggered only by a finding that the area has failed to
attain the standard by the attainment date.\33\ In other words, as with
Serious and above areas, a determination of attainment by the
attainment date for a Moderate area serves as demonstration that RFP
requirements for the area have been met and that RFP contingency
measures are no longer needed. Thus, the EPA concludes that RFP
contingency measures for Moderate areas are no longer needed if the
area has attained the relevant NAAQS. Accordingly,
[[Page 23505]]
because we have proposed to determine that the Mariposa area has
attained the 2015 ozone NAAQS by the attainment date, we are now also
proposing to determine that RFP contingency measures are no longer
required for this standard in this area. Therefore, if we finalize our
proposed determination of attainment by the attainment date, neither
attainment nor RFP contingency measures would be required for the
Mariposa area for the 2015 ozone NAAQS.
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\32\ CAA section 182(g)(1) (exempting areas classified as
Moderate from milestone requirements).
\33\ See 57 FR 13498, 13511 (April 16, 1992) (contrasting
Moderate areas, for which ``contingency measures would be needed
when the area fails to attain the standard by the attainment date''
with Serious and above areas, for which contingency measures would
also be triggered ``if the area fails to meet the rate-of-progress
requirements for any milestone other than one falling on an
attainment year''). See also memorandum dated March 11, 1993, from
G.T. Helms, Chief Ozone/Carbon Monoxide Programs Branch, to Air
Branch Chief, Regions I-X (``The test for moderate areas will be
whether they attained the standard because the attainment date for
moderate areas coincides with the milestone demonstration date.
Failure to attain will cause an area to be required to implement its
contingency measures . . .'').
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III. Summary of Proposal
We are proposing to determine that the Mariposa area attained the
2015 ozone NAAQS by the August 3, 2024 attainment date based on
quality-assured and certified ambient air quality monitoring data from
2021 through 2023. If this action is finalized, the CAA requirement for
the SIP to provide for attainment and RFP contingency measures will no
longer apply to the Mariposa area for the 2015 ozone NAAQS. If
finalized, the EPA's obligation under section 181(b)(2)(A) to determine
whether the Mariposa area attained by its attainment date will no
longer apply and the area will not be reclassified. The area will
remain designated nonattainment and thus the State will continue to
comply with applicable requirements for a Moderate ozone nonattainment
area.
IV. Statutory and Executive Order Reviews
This rulemaking proposes to make an attainment determination based
on air quality data and would, if finalized, result in the suspension
of certain Federal requirements and would not impose any additional
requirements. Additional information about these statutes and Executive
Orders can be found at <a href="https://www.epa.gov/laws-regulations/laws-and-executive-orders">https://www.epa.gov/laws-regulations/laws-and-executive-orders</a>.
A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review
This action is not a significant regulatory action and was
therefore not submitted to the Office of Management and Budget (OMB)
for review.
B. Executive Order 14192: Unleashing Prosperity Through Deregulation
Executive Order 14192 does not apply because actions that make
attainment determinations under Clean Air Act section 181(b)(2) are
exempted from review under Executive Order 12866.
C. Paperwork Reduction Act (PRA)
This action does not impose an information collection burden under
the PRA because this action does not impose additional requirements
beyond those imposed by state law.
D. 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. This
action will not impose any requirements on small entities beyond those
imposed by state law.
E. 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. This action does not impose additional requirements
beyond those imposed by state law. Accordingly, no additional costs to
state, local, or Tribal governments, or to the private sector, will
result from this action.
F. 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.
G. Executive Order 13175: Coordination With Indian Tribal Governments
This action does not have tribal implications, as specified in
Executive Order 13175, because the action 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, and will
not impose substantial direct costs on Tribal governments or preempt
Tribal law. Thus, Executive Order 13175 does not apply to this action.
H. Executive Order 13045: Protection of Children From Environmental
Health Risks 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.
I. 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.
J. National Technology Transfer and Advancement Act (NTTAA)
Section 12(d) of the NTTAA directs the EPA to use voluntary
consensus standards in its regulatory activities unless to do so would
be inconsistent with applicable law or otherwise impractical. The EPA
believes that this action is not subject to the requirements of section
12(d) of the NTTAA because application of those requirements would be
inconsistent with the CAA.
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.
(Authority: 42 U.S.C. 7401 et seq.)
Dated: May 21, 2025.
Joshua F.W. Cook,
Regional Administrator, Region IX.
[FR Doc. 2025-09999 Filed 6-2-25; 8:45 am]
BILLING CODE 6560-50-P
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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.