# 91 FR 35437: Attainment Date Extension for the San Joaquin Valley, California 2012 Annual PM2.5 Fine Particulate Matter Nonattainment Area

> Federal · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/FR_PRORULE_2026-11735

## Section

- **Citation:** 91 FR 35437
- **Heading:** Attainment Date Extension for the San Joaquin Valley, California 2012 Annual PM2.5 Fine Particulate Matter Nonattainment Area
- **Jurisdiction:** Federal
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Federal Register / Vol. 91 / 91 FR 35437

## Text

ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [EPA-R09-OAR-2026-3665; FRL-13380-01-R9] Attainment Date Extension for the San Joaquin Valley, California 2012 Annual PM 2.5 Fine Particulate Matter Nonattainment Area AGENCY:
Environmental Protection Agency (EPA).

ACTION:
Proposed rule.

SUMMARY:
The Environmental Protection Agency (EPA) is proposing to grant an extension of the applicable “Serious” area attainment date for the San Joaquin Valley nonattainment area for the 2012 annual fine particulate matter (PM 2.5 ) national ambient air quality standards (NAAQS or “standards”) from December 31, 2025, to December 31, 2030, based on a proposed determination that the State has satisfied the statutory criteria for this extension. The EPA will accept comments on this proposed rulemaking during a 30-day public comment period.

DATES:
Comments must be received on or before July 13, 2026.

ADDRESSES:
Submit your comments, identified by Docket ID No. EPA-R09-OAR-2026-3665 at https://www.regulations.gov. For comments submitted at Regulations.gov , follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov . 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
The District works cooperatively with the California Air Resources Board (CARB) in preparing these plans. Authority for regulating sources in the San Joaquin Valley nonattainment area is split between the District, which has responsibility for regulating stationary and most area sources, and CARB, which has responsibility for regulating most mobile sources and some categories of consumer products.
4 For a precise description of the geographic boundaries of the San Joaquin Valley PM 2.5 nonattainment area, see 40 CFR 81.305.
Following promulgation of a new or revised NAAQS, the EPA is required under CAA section 107(d) to designate areas throughout the nation as attaining or not attaining the NAAQS. On January 15, 2015, the EPA designated and classified the San Joaquin Valley as “Moderate” nonattainment for the 2012 PM 2.5 NAAQS. 5
5 80 FR 2206 (January 15, 2015) (codified at 40 CFR 81.305).
On May 10, 2019, CARB made two SIP submissions to address the CAA requirements associated with the 2012 annual PM 2.5 NAAQS in the San Joaquin Valley: the “2016 Moderate Area Plan for the 2012 PM 2.5 Standard” (“2016 PM 2.5 Plan”) and the “2018 Plan for the 1997, 2006, and 2012 PM 2.5 Standards” (“2018 PM 2.5 Plan”). 6 On December 13, 2019, CARB submitted additional documents supporting the 2016 and 2018 PM 2.5 Plans that were inadvertently omitted from the May 10, 2019 SIP submission. 7 The 2016 PM 2.5 Plan included a demonstration, to address the requirements of CAA section 189(a)(1)(B), that attainment of the 2012 annual PM 2.5 NAAQS by the December 31, 2021 Moderate area attainment date in the San Joaquin Valley was impracticable. 8 The 2018 PM 2.5 Plan addressed the Serious area attainment plan requirements for the 2012 PM 2.5 NAAQS in anticipation of the reclassification of San Joaquin Valley from Moderate to Serious nonattainment for that PM 2.5 NAAQS
AA section 189(a)(1)(B), that attainment of the 2012 annual PM 2.5 NAAQS by the December 31, 2021 Moderate area attainment date in the San Joaquin Valley was impracticable. 8 The 2018 PM 2.5 Plan addressed the Serious area attainment plan requirements for the 2012 PM 2.5 NAAQS in anticipation of the reclassification of San Joaquin Valley from Moderate to Serious nonattainment for that PM 2.5 NAAQS. Lastly, in 2023, CARB submitted two additional SIP revisions addressing contingency measure requirements for the San Joaquin Valley for numerous standards including the 2012 annual PM 2.5 NAAQS. 9 These SIP revisions are referred to herein as the “2023 Contingency Measure SIP Submittals.”
6 CARB submitted the two plans electronically on May 10, 2019, as an attachment to a letter dated May 9, 2019, from Richard W. Corey, Executive Officer, CARB, to Mike Stoker, Regional Administrator, EPA Region IX.
7 Letter dated December 11, 2019, from Richard W. Corey, Executive Officer, CARB, to Mike Stoker, Regional Administrator, EPA Region IX, with enclosures.
8 86 FR 67343, 67346 (November 26, 2021).
9 CARB submitted the “PM 2.5 Contingency Measure State Implementation Plan Revision (May 18, 2023)” and amendments to District Rule 4901 (Wood Burning Fireplaces and Wood Burning Heaters) to the EPA on June 8, 2023. See letter dated June 7, 2023, from Steven S. Cliff, Ph.D., Executive Officer, CARB, to Martha Guzman, Regional Administrator, EPA Region IX. CARB submitted amendments to District Rule 8051 (Open Areas) to the EPA on October 16, 2023. See letter dated October 13, 2023, from Steven S. Cliff, Ph.D., Executive Officer, CARB, to Martha Guzman, Regional Administrator, EPA Region IX.
Effective December 27, 2021, the EPA approved all of the 2012 annual PM 2.5 Moderate area requirements included in the 2016 PM 2.5 Plan except for contingency measures and, pursuant to CAA section 188(b)(1), reclassified the area as a Serious nonattainment area for the 2012 annual PM 2.5 NAAQS
even S. Cliff, Ph.D., Executive Officer, CARB, to Martha Guzman, Regional Administrator, EPA Region IX.
Effective December 27, 2021, the EPA approved all of the 2012 annual PM 2.5 Moderate area requirements included in the 2016 PM 2.5 Plan except for contingency measures and, pursuant to CAA section 188(b)(1), reclassified the area as a Serious nonattainment area for the 2012 annual PM 2.5 NAAQS. 10 The EPA took final action to approve the 2023 Contingency Measure SIP Submittals as satisfying the Moderate contingency measure requirement for the San Joaquin Valley 2012 annual PM 2.5 nonattainment area on October 4, 2024. 11
10 86 FR 67343, 67346 and 67347 (November 26, 2021).
11 89 FR 80749 (October 4, 2024).
Upon reclassification as a Serious PM 2.5 nonattainment area, the San Joaquin Valley area became subject to a new statutory attainment date of as expeditiously as practicable but no later than the end of the tenth calendar year following designation ( i.e., December 31, 2025) and a requirement to submit a Serious area plan satisfying the requirements of CAA title I, part D, including the requirements of subpart 4, for the 2012 annual PM 2.5 NAAQS. 12 As explained in the EPA's final reclassification action, the Serious area plan for the San Joaquin Valley must include, among other things, provisions to assure that, under CAA section 189(b)(1)(B), the best available control measures (BACM) for the control of direct PM 2.5 and PM 2.5 precursors shall be implemented no later than four years after the area is reclassified and a demonstration (including air quality modeling) that the plan provides for attainment as expeditiously as practicable and no later than the applicable attainment date. The EPA also noted that California may choose to submit a request for an extension of the December 31, 2025 Serious area attainment date pursuant to CAA section 188(e)
74310 (December 29, 2021).
16 87 FR 60494 (October 5, 2022).
17 Letter dated October 27, 2022, from Samir Shiekh, Executive Director, SJVUAPCD, to Martha Guzman, Regional Administrator, EPA Region IX, and letter dated October 27, 2022, from Steven S. Cliff, Executive Officer, CARB, to Martha Guzman, Regional Administrator, EPA Region IX (both letters submitted electronically October 27, 2022).
On November 21, 2023, CARB submitted the “Initial SIP Requirements for the 2012 Annual PM 2.5 Standard,” which addressed Serious area requirements for the San Joaquin Valley 2012 annual PM 2.5 nonattainment area, including emissions inventory and BACM requirements. 18 On August 22, 2.5 Standard” (“2024 San Joaquin Valley PM 2.5 Plan” or “Plan”), adopted by SJVUAPCD on June 20, 2024, and by CARB on July 25, 2024. 19 The 2024 San Joaquin Valley PM 2.5 Plan addresses the Serious area nonattainment plan requirements for the 2012 annual PM 2.5 NAAQS in the San Joaquin Valley nonattainment area and includes a request under CAA section 188(e) for an extension of the Serious area attainment date for the area for these NAAQS from December 31, 2025, to December 31, 2030.
18 Letter dated November 17, 2023, from Steven S. Cliff, Executive Officer, CARB, to Martha Guzman, Regional Administrator, EPA Region IX, with enclosures (submitted electronically on November 21, 2023).
19 Letter dated August 22, 2024, from Steven S. Cliff, Executive Officer, CARB, to Martha Guzman, Regional Administrator, EPA Region IX, with enclosures (submitted electronically on August 22, 2024).
II. Completeness Review of the 2024 San Joaquin Valley PM 2.5 Plan
CAA sections 110(a)(1) and (2) and 110(l) require each State to provide reasonable public notice and opportunity for public hearing prior to the adoption and submission of a SIP or SIP revision to the EPA
satisfaction of the Administrator that the plan for the area includes the “most stringent measures” (MSM) that are included in the implementation plan of any state or are achieved in practice in any state and can feasibly be implemented in the area;
(4) Submit a modeled attainment demonstration showing attainment of the NAAQS in the area by the most expeditious alternative date practicable; and
(5) Apply for an extension of the attainment date beyond the Serious area attainment date. 21
21 CAA section 188(e) and 40 CFR 51.1005(b). For a discussion of the EPA's interpretation of the requirements of CAA section 188(e), see 81 FR 58010, 58094 through 58097 (August 24, 2016), and 59 FR 41998, 42002 (August 16, 1994).
A State must seek an extension of the Serious area attainment date at the same time it submits the Serious area attainment plan if the State cannot demonstrate attainment by the otherwise applicable statutory attainment date. 22
22 40 CFR 51.1005(b)(2).
The EPA established regulatory requirements and provided further interpretive guidance on the statutory SIP requirements that apply to areas designated nonattainment for the PM 2.5 standards in an August 24, 2016 final rule entitled “Fine Particulate Matter National Ambient Air Quality Standards: State Implementation Plan Requirements” (“PM 2.5 SIP Requirements Rule”). Under the EPA's regulations at 40 CFR 51.1005(b)(2), a State seeking an extension of the Serious area attainment date under CAA section 188(e) must also submit a Serious area attainment plan that meets the following requirements:
(1) Base year and attainment projected emissions inventory requirements in 40 CFR 51.1008(b);
(2) The MSM requirement in 40 CFR 51.1005(b)(1)(iii) and 51.1010(b), and best available control measures not previously submitted;
(3) Attainment demonstration and modeling requirements in 40 CFR 51.1011 and 40 CFR 51.1005(b)(1)(i);
(4) Reasonable further progress (RFP) requirements in 40 CFR 51.1012;
(e) include the specific ambient air quality conditions in CAA section 188(d)(2) that must be met for an area to qualify for an extension of a Moderate area attainment date.
24 CAA section 188(e).
The EPA is evaluating the State's request for an extension of the Serious area attainment date in accordance with these statutory criteria and regulatory requirements, as further described below.
1. Demonstrate That Attainment by the Serious Area Attainment Date Is Impracticable
Section 188(e) of the Act authorizes the EPA to grant a State request for an extension of the Serious area attainment date if, among other things, attainment by the date established under CAA section 188(c) would be impracticable. In order to demonstrate impracticability, 25 For the San Joaquin Valley, the Serious area attainment date for the 2012 annual PM 2.5 NAAQS under CAA section 188(c)(2) is December 31, 2025. 26
25 81 FR 58010, 58094 (August 24, 2016).
26 Under CAA section 188(c)(2), the attainment date for a Serious area “shall be as expeditiously as practicable but no later than the end of the tenth calendar year beginning after the area's designation as nonattainment. . . .” The EPA designated the San Joaquin Valley as nonattainment for the 2012 annual PM 2.5 NAAQS effective April 15, 2015 (80 FR 2206 (January 15, 2015)). Therefore, the latest permissible attainment date under CAA section 188(c)(2), for purposes of the 2012 annual PM 2.5 NAAQS in this area, is December 31, 2025.
The EPA has defined BACM in the PM 2.5 SIP Requirements Rule to mean “any technologically and economically feasible control measure that can be implemented in whole or in part within 4 years after the date of reclassification of a Moderate PM 2.5 nonattainment area to Serious and that generally can achieve greater permanent and enforceable emissions reductions in direct PM 2.5 emissions and/or emissions of PM 2.5 plan precursors from sources in the area than can be achieved through the implementation of RACM on the same source(s)
t can be implemented in whole or in part within 4 years after the date of reclassification of a Moderate PM 2.5 nonattainment area to Serious and that generally can achieve greater permanent and enforceable emissions reductions in direct PM 2.5 emissions and/or emissions of PM 2.5 plan precursors from sources in the area than can be achieved through the implementation of RACM on the same source(s). BACM includes BACT.” 27
27 40 CFR 51.1000 (definitions). In longstanding guidance, the EPA has similarly defined BACM to mean, “among other things, the maximum degree of emissions reduction achievable for a source or source category, which is determined on a case-by-case basis considering energy, environmental, and economic impacts.” 59 FR 41998, 42010, 42013 (August 16, 1994).
Consistent with longstanding EPA guidance, 28 the preamble to the PM 2.5 SIP Requirements Rule discusses the following steps for determining BACM and BACT:
28 59 FR 41998 (August 16, 1994).
(1) Develop a comprehensive emissions inventory of the sources of PM 2.5 and PM 2.5 precursors;
(2) Identify potential control measures;
(3) Determine whether an available control measure or technology is technologically feasible;
(4) Determine whether an available control measure or technology is economically feasible; and
(5) Determine the earliest date by which a control measure or technology can be implemented in whole or in part. 29
29 81 FR 58010, 58083 through 58085 (August 24, 2016).
The EPA allows consideration of factors such as physical plant layout, energy requirements, needed infrastructure, and workforce type and habits when considering technological feasibility. For purposes of evaluating economic feasibility, the EPA allows consideration of factors such as the capital costs, operating and maintenance costs, and cost effectiveness ( i.e., cost per ton of pollutant reduced by a measure or technology) associated with the measure or control. 30
30 40 CFR 51.1010(a)(3) and 81 FR 58010, 58041 and 58042 (August 24, 2016).
2
dering technological feasibility. For purposes of evaluating economic feasibility, the EPA allows consideration of factors such as the capital costs, operating and maintenance costs, and cost effectiveness ( i.e., cost per ton of pollutant reduced by a measure or technology) associated with the measure or control. 30
30 40 CFR 51.1010(a)(3) and 81 FR 58010, 58041 and 58042 (August 24, 2016).
2. Comply With All Requirements and Commitments in the Applicable Implementation Plan
A second precondition for an extension of the Serious area attainment date under CAA section 188(e) is a showing that the State has complied with all requirements and commitments pertaining to that area in the implementation plan. We interpret this criterion to mean that the state has implemented the control measures and commitments in the SIP revisions it has submitted to address the applicable requirements in CAA sections 172 and 189 for that particular PM 2.5 nonattainment area, in this case the San Joaquin Valley nonattainment area for the 2012 annual PM 2.5 NAAQS. 31 For a Serious area attainment date extension request being submitted simultaneously with the initial Serious area attainment plan for the area, the EPA interprets CAA section 188(e) not to require the area to have a fully approved Moderate area attainment plan and to allow for extension of the attainment date if the area has complied with all Moderate area requirements and commitments pertaining to that area in the State's submitted Moderate area implementation plan. 32 This interpretation is based on the plain language of CAA section 188(e), which requires the State to comply with all requirements and commitments pertaining to the area in the implementation plan
ow for extension of the attainment date if the area has complied with all Moderate area requirements and commitments pertaining to that area in the State's submitted Moderate area implementation plan. 32 This interpretation is based on the plain language of CAA section 188(e), which requires the State to comply with all requirements and commitments pertaining to the area in the implementation plan. 33
31 Although the EPA has previously interpreted this requirement as applying to additional PM 2.5 NAAQS for the same area (see 85 FR 17382, 17405), this position is not required by the statute or our regulations, and the EPA no longer believes that this interpretation is the best available reading of the Act. The EPA maintains that the implementation of a plan developed for an entirely separate NAAQS should not have an impact on the relevant requirements for the NAAQS at issue. There is no indication that Congress intended such an additional hurdle for areas that are in nonattainment for multiple NAAQS. Accordingly, the EPA believes that the best interpretation of the statute is that “compliance with all requirements and commitments pertaining to that area in the implementation plan” refers only to the implementation plan for the particular NAAQS at issue.
32 81 FR 58010, 58095 (August 24, 2016).
33 The Ninth Circuit Court of Appeals upheld this interpretation of CAA section 188(e) in Vigil v. Leavitt, 366 F.3d 1025, amended at 381 F.3d 826 (9th Cir. 2004).
3. Demonstrate the Inclusion of the Most Stringent Measures
A third precondition for an extension of the Serious area attainment under CAA section 188(e) is for the State to demonstrate to the satisfaction of the Administrator that the plan for the area includes the MSM that are included in the implementation plan of any state, or are achieved in practice in any state, and can feasibly be implemented in the area
e Inclusion of the Most Stringent Measures
A third precondition for an extension of the Serious area attainment under CAA section 188(e) is for the State to demonstrate to the satisfaction of the Administrator that the plan for the area includes the MSM that are included in the implementation plan of any state, or are achieved in practice in any state, and can feasibly be implemented in the area. The EPA has defined the term MSM as “any permanent and enforceable control measure that achieves the most stringent emissions reductions in direct PM 2.5 emissions and/or emissions of PM 2.5 plan precursors from among those control measures which are either included in the SIP for any other NAAQS, or have been achieved in practice in any state, and that can feasibly be implemented in the relevant PM 2.5 NAAQS nonattainment area.” 34 The EPA has interpreted the Act to require implementation of MSM as expeditiously as practicable and no later than one year before the extended Serious area attainment date identified by the State in its extension request. 35
34 40 CFR 51.1000 and 81 FR 58010, 58096 and 58097 (August 24, 2016); see also 59 FR 41998, 42010 (August 16, 1994) and 65 FR 19964, 19968 (April 13, 2000).
35 81 FR 58010, 58097 (August 24, 2016).
An MSM demonstration must satisfy the requirements of the PM 2.5 SIP Requirements Rule as described in the preamble to the rule, as follows: 36
36 40 CFR 51.1010(b) and 81 FR 58010, 58095 through 58097 (August 24, 2016).
(1) Update the emissions inventory to identify all sources of direct PM 2.5 and PM 2.5 precursor emissions in the nonattainment area;
(2) Identify all potential MSM to reduce emissions from sources of direct PM 2.5 and PM 2.5 plan precursors that are approved into any state implementation plan or used in practice in any state;
51.1010(b) and 81 FR 58010, 58095 through 58097 (August 24, 2016).
(1) Update the emissions inventory to identify all sources of direct PM 2.5 and PM 2.5 precursor emissions in the nonattainment area;
(2) Identify all potential MSM to reduce emissions from sources of direct PM 2.5 and PM 2.5 plan precursors that are approved into any state implementation plan or used in practice in any state;
(3) Compare the potential MSM for each relevant source category to the measures, if any, already adopted for that source category in the nonattainment area to determine whether such potential MSM would further reduce emissions and, where the State chooses to reject a measure from further consideration, demonstrate that it is not technologically or economically feasible to implement the measure in whole or in part within five years after
(4) Adopt and implement all potential MSM identified through this process that collectively will achieve attainment as expeditiously as practicable and no later than five years after the applicable attainment date, except those measures for which the state has provided reasoned justification for rejection, based on technological or economic feasibility.
Notably, the “to the satisfaction of the Administrator” qualifier on the MSM requirement is an explicit grant by Congress to the EPA of discretion to determine whether a plan includes MSM.
4. Submit a Demonstration of Attainment by the Most Expeditious Alternative Date Practicable
Section 189(b)(1)(A) of the Act requires that the State submit a demonstration of attainment, including air quality modeling, by the most expeditious date practicable after the statutory Serious area attainment date. 37 Section 188(e) of the CAA states that the threshold requirement is submission of such a demonstration. 38 Accordingly, the EPA must evaluate whether the submission containing the extension request also includes such a demonstration.
37 Id. at 58097
stration of attainment, including air quality modeling, by the most expeditious date practicable after the statutory Serious area attainment date. 37 Section 188(e) of the CAA states that the threshold requirement is submission of such a demonstration. 38 Accordingly, the EPA must evaluate whether the submission containing the extension request also includes such a demonstration.
37 Id. at 58097.
38 The CAA does not require the EPA to act on the submitted attainment demonstration as a precondition to granting an extension. Section 188(e) of the Act states that “[a]t the time of such application, the State must submit a revision to the implementation plan that includes a demonstration of attainment by the most expeditious alternative date practicable.” In particular, the statute provides that “[t]he Administrator may not approve an extension until the State submits an attainment demonstration for the area.”
5. Apply for an Attainment Date Extension
Finally, the State must apply in writing to the EPA for an extension of a Serious area attainment date, and this request must accompany the submission of the modeled attainment demonstration showing attainment by the most expeditious alternative date practicable. Additionally, the State must provide the public reasonable notice and opportunity for a public hearing on the attainment date extension request before submitting it to the EPA in accordance with the requirements for SIP revisions in CAA section 110.
IV. Review of the State's Request
In this section of the preamble, we present our evaluation of the State's request to extend the Serious area attainment date from December 31, 2025, to December 31, 2030, under CAA section 188(e).
A. Demonstration That Attainment by Serious Area Attainment Date Is Impracticable
The 2024 San Joaquin Valley PM 2.5 Plan includes a demonstration, based on air quality modeling, that even with the implementation of BACM and BACT for all appropriate sources, attainment by December 31, 2025, is not practicable
tainment date from December 31, 2025, to December 31, 2030, under CAA section 188(e).
A. Demonstration That Attainment by Serious Area Attainment Date Is Impracticable
The 2024 San Joaquin Valley PM 2.5 Plan includes a demonstration, based on air quality modeling, that even with the implementation of BACM and BACT for all appropriate sources, attainment by December 31, 2025, is not practicable. The impracticability demonstration is described in Chapter 5.2.1 of the Plan and references the modeling information provided in Appendix J of the Plan. The BACM/BACT demonstration is included in Appendices C (for District measures) and D (for State measures) of the Plan. Because of the substantial overlap in the source categories and controls evaluated for BACM and those evaluated for MSM, the BACM demonstration is discussed alongside our evaluation of the Plan's MSM demonstration in section IV.C of this document.
Table 26 in Appendix J of the plan presents modeled 2030 annual PM 2.5 design values. The results of the District's modeling are summarized in table 1 of this document.
Table 1—Impracticability Demonstration, 2030 Projected PM 2.5 Design Values Site AQS ID Name 2017 Monitored annual design value (µg/m 3 ) 2030 Projected annual design value (µg/m 3 ) 060290016 Bakersfield—Planz 16.97 11.98 060311004 Hanford 15.73 11.04 060290010 Bakersfield—Golden 15.52 10.82 061072002 Visalia 15.43 10.50 060290014 Bakersfield—California Ave 15.12 10.52 060310004 Corcoran 14.95 10.90 060195025 Fresno—Hamilton 13.99 9.81 060190011 Fresno—Garland 13.69 9.49 060990006 Turlock 12.7 9.69 060195001 Clovis 12.69 8.99 060470003 Merced—S. Coffee 12.28 9.31 060771002 Stockton 12.21 10.16 060392010 Madera 12.11 8.75 060472510 Merced—M. Street 11.73 8.73 060990005 Modesto 11.16 8.54 060772010 Manteca 10.37 8.38 060192009 Tranquillity 8.19 6.37 Source: 2024 San Joaquin Valley PM 2.5 Plan, Chapter 5, Table 5-3
ford—Irwin 12.5 11.8 11.8 11.8 0.0 Visalia—W. Ashland Avenue 11.7 13.0 11.5 11.7 1.7 Source: EPA, AQS Design Value Report (AMP480), Report Request ID 2384983, May 28, 2026. The EPA found that three monitoring sites in the San Joaquin Valley Air Basin would need to have 2025 annual mean concentrations 19 percent or more below their corresponding historical lows in order to attain by the end of 2025. The most extreme example is the Bakersfield-Airport (Planz) monitoring site, which would require concentrations approximately 35 percent below the lowest previously recorded concentration at this site. Considering the District's assertion that the control strategy in the 2024 San Joaquin Valley PM 2.5 Plan includes all BACM and MSM, there is no indication that the control strategy could achieve such steep reductions so quickly.
In sum, the District's air quality modeling projections for 2030, which account for the implementation of controls according to the implementation schedules submitted in the Plan, and monitored air quality data from 2023 and 2024 indicate that it is impracticable for the San Joaquin Valley nonattainment area to show attainment of the 2012 annual PM 2.5 NAAQS by December 31, 2025. Thus, our review of the impracticability demonstration and related information in the Plan as well as monitoring data from the San Joaquin Valley nonattainment area indicate that the area could not practicably attain the 2012 annual PM 2.5 NAAQS by the applicable attainment date of December 31, 2025.
B. Compliance With State Implementation Plan Requirements and Commitments
We interpret this criterion to mean that the State has implemented the control measures and commitments in the plan revisions it has submitted to address the applicable requirements in CAA sections 172 and 189 for the relevant PM 2.5 NAAQS for the nonattainment area
by the applicable attainment date of December 31, 2025.
B. Compliance With State Implementation Plan Requirements and Commitments
We interpret this criterion to mean that the State has implemented the control measures and commitments in the plan revisions it has submitted to address the applicable requirements in CAA sections 172 and 189 for the relevant PM 2.5 NAAQS for the nonattainment area. 40 For the San Joaquin Valley for the 2012 annual PM 2.5 NAAQS, the State has submitted, and the EPA has approved into the California SIP, the control measure requirements and commitments in the 2016 PM 2.5 Plan that pertained to the Moderate area planning requirements for the 2012 annual PM 2.5 NAAQS. In the remainder of this section, we describe the State's and District's implementation of those control measures.
40 81 FR 58010, 58094 (August 24, 2016). Under 40 CFR 51.1005(b)(ii), a State must have complied with all requirements and commitments in the applicable implementation plan. The applicable attainment plan for a Serious PM 2.5 nonattainment area for which a State seeks an attainment date extension under 40 CFR 51.1005(a)(2)(ii) is defined as the Moderate area plan submitted to meet the requirements of 40 CFR 51.1003(a).
As discussed in section I of this document, CARB submitted the 2016 PM 2.5 Plan to the EPA on May 10, 2019. On November 26, 2021, the EPA approved all but the contingency measure element of the submitted SIP revision as meeting all applicable Moderate area requirements for the 2012 annual PM 2.5 NAAQS. 41 The EPA approved the 2012 annual PM 2.5 Moderate area contingency measure element for the San Joaquin Valley on October 4, 2024. 42
41 86 FR 67343 (November 26, 2021).
42 89 FR 80749 (October 4, 2024).
The 2024 San Joaquin Valley PM 2.5 plan addresses compliance with the applicable 2016 PM 2.5 Plan Moderate area planning requirements and commitments for the 2012 annual PM 2.5 NAAQS in Chapter 5.2.2 of the Plan
e 2012 annual PM 2.5 Moderate area contingency measure element for the San Joaquin Valley on October 4, 2024. 42
41 86 FR 67343 (November 26, 2021).
42 89 FR 80749 (October 4, 2024).
The 2024 San Joaquin Valley PM 2.5 plan addresses compliance with the applicable 2016 PM 2.5 Plan Moderate area planning requirements and commitments for the 2012 annual PM 2.5 NAAQS in Chapter 5.2.2 of the Plan. While the 2016 PM 2.5 Plan includes an evaluation of potential control measures for adoption as RACM, RACT, or additional reasonable measures, the District did not identify any feasible control measures beyond those that had already been adopted and implemented, and thus the District did not include any commitments for additional measures for purposes of meeting the Moderate area planning requirements. Given that the EPA has fully approved the Moderate area planning requirements for the area and that there are no outstanding commitments or other obligations relating to those requirements, our review indicates that the State has complied with all requirements and commitments in the plan revisions it has submitted to address the applicable requirements in CAA sections 172 and 189 for the 2012 annual PM 2.5 NAAQS for the San Joaquin Valley nonattainment area.
C. Demonstration That the Implementation Plan Includes the Most Stringent Measures
Before the EPA may extend the attainment date for a Serious nonattainment area under CAA section 188(e), the State must, among other things, demonstrate to the satisfaction of the Administrator that the plan for the area includes the most stringent measures (MSM) that are included in the implementation plan of any state, or are achieved in practice in any state, and can feasibly be implemented in the area. The State must implement MSM as expeditiously as practicable and no later than the beginning of the year containing the attainment date identified by the State in its extension request, i.e., in this case, by January 1, 2030
SIP Requirements Rule, generally: (1) an emissions inventory identifying sources of emissions of direct PM 2.5 and applicable precursors; (2) identifying potential control measures for the sources identified in step 1; (3) assessing the stringency and feasibility of the control measures identified in step 2; and (4) adoption and implementation of the feasible control measures identified in step 3. 45
44 Appendix F of 2024 San Joaquin Valley PM 2.5 Plan contains a demonstration that emissions of VOC, SO X , and ammonia do not contribute significantly to exceedances of the 2012 annual PM 2.5 NAAQS in the San Joaquin Valley nonattainment area and that such emissions should be excluded from certain CAA requirements (including BACM and MSM), consistent with the EPA's recommendations in the “Fine Particulate Matter (PM 2. ) Precursor Demonstration Guidance” (see memorandum dated May 30, 2019, from Scott Mathias, Acting Director, Air Quality Policy Division, EPA Office of Air Quality Planning and Standards (OAQPS), and Richard Wayland, Director, Air Quality Assessment Division, OAQPS, to Regional Air Division Directors, Regions 1-10, with attachment titled “PM 2.5 Precursor Demonstration Guidance;” available at https://www.epa.gov/sites/default/files/2019-05/documents/transmittal_memo_and_pm25_precursor_demo_guidance_5_30_19.pdf ). The BACM and MSM evaluations in the Plan therefore focus on sources of emissions of direct PM 2.5 and NO X and excludes sources of VOC and SO X, and ammonia.
45 2024 San Joaquin Valley PM 2.5 Plan, section 5.2.3.
CARB's demonstration includes descriptions of CARB's key mobile source programs and regulations and a comprehensive evaluation of on-road and non-road mobile source regulatory actions taken by CARB and other states. Based on its review, CARB determined that its control program for sources under its jurisdiction satisfies BACM and MSM requirements
24 San Joaquin Valley PM 2.5 Plan, section 5.2.3.
CARB's demonstration includes descriptions of CARB's key mobile source programs and regulations and a comprehensive evaluation of on-road and non-road mobile source regulatory actions taken by CARB and other states. Based on its review, CARB determined that its control program for sources under its jurisdiction satisfies BACM and MSM requirements.
The District followed a similar process to identify candidate BACM/MSM measures that are technologically and economically feasible for stationary and area sources under its jurisdiction. The District structured its evaluation around its existing control program; for each existing District rule, the District identified the affected sources and associated emissions of direct PM 2.5 and NO X , identified potential opportunities for further emissions reductions by comparing the District rule to Federal and State rules and regulations and rules in other California air districts (as well as potential new technologies not yet required in other areas, in some instances) and evaluated technological and economic feasibility of each potential emissions reduction opportunity. For most source categories, the District found that its existing control measures provide the maximum degree of emission reduction required or implemented in any other area. For all identified potential emission reduction opportunities, the District concluded that the potential measure was infeasible due to economic and/or technological considerations. Thus, the District concluded that, for all sources of direct PM 2.5 or PM 2.5 precursors in the San Joaquin Valley nonattainment area, the District's existing control program provides for the maximum degree of emission reduction that has been required or achieved in other areas that can feasibly be implemented in the nonattainment area and therefore meets or exceeds BACM and MSM requirements
nt by the most expeditious alternative date practicable and that the EPA may not approve the extension until such a demonstration has been submitted. Section 189(b)(1)(A)(ii) of the CAA also provides that a State seeking an extension of the attainment date under CAA section 188(e) must submit a demonstration that the plan provides for attainment by the most expeditious alternative date practicable.
For the purpose of the CAA section 188(e) requirement that the District submit a demonstration that the plan provides for attainment by the most expeditious alternative date practicable, the EPA's review of the submission indicates that the submission contains the requisite demonstration. Chapter 5.2.4.2 and Appendix J of the 2024 San Joaquin Valley PM 2.5 Plan contain the State's demonstration that the implementation of all feasible control measures in the San Joaquin Valley, as required in the Plan, will provide for attainment of the 2012 annual PM 2.5 NAAQS in the San Joaquin Valley as expeditiously as practicable, i.e., by December 31, 2030. Furthermore, the District cites Appendix G of the Plan as validating the assertion in the Plan that the San Joaquin Valley will attain the standard as expeditiously as practicable. 48 Appendix G addresses the reasonable further progress, quantitative milestone, and contingency measure requirements and includes an evaluation of potential control measures for consideration as contingency measures. As a result of this evaluation, the District concludes that the District and CARB are currently implementing the most stringent measures feasible, and no opportunities exist for additional measures beyond those adopted in the Plan, supporting the District's position that the San Joaquin Valley could not practicably attain the 2012 annual PM 2.5 NAAQS sooner than December 31, 2030, as projected in the attainment demonstration in the Plan
rict concludes that the District and CARB are currently implementing the most stringent measures feasible, and no opportunities exist for additional measures beyond those adopted in the Plan, supporting the District's position that the San Joaquin Valley could not practicably attain the 2012 annual PM 2.5 NAAQS sooner than December 31, 2030, as projected in the attainment demonstration in the Plan. In addition, the RFP demonstration in Appendix G reports the most expeditious timeline by which the San Joaquin Valley can achieve emissions reductions from the implementation of BACM and MSM in light of factors such as the timeline required for the development, adoption, and implementation of the rules included in the Plan, supporting the District's position that the San Joaquin Valley could not practicably attain the 2012 annual PM 2.5 NAAQS sooner than December 31, 2030, as projected in the attainment demonstration in the Plan.
48 2024 San Joaquin Valley PM 2.5 Plan, Chapter 5.2.4.2.
While the EPA will evaluate this analysis in a future rulemaking action, for the purpose of the CAA section 188(e) extension prerequisite that a complete submission from the State must contain the requisite demonstration under CAA section 189(b)(1)(A)(ii), our review of the 2024 San Joaquin Valley PM 2.5 Plan indicates that the State has made such a submission.
E. Application for an Attainment Date Extension
As discussed in section I.B of this document, the Serious area attainment date for the San Joaquin Valley for the 2012 annual PM 2.5 NAAQS under CAA section 188(c)(2) is December 31, 2025. The remaining criterion for an extension of the attainment date beyond this statutory attainment date is that the State must apply for such extension. In the 2024 San Joaquin Valley PM 2.5 Plan, CARB and SJVUAPCD submitted a complete application for an extension of the Serious area attainment date for the San Joaquin Valley to December 31, 2030, for the 2012 annual PM 2.5 NAAQS
the reasons discussed in this proposed rulemaking, the EPA is proposing to grant the State's request for an extension of the Serious area attainment date from December 31, 2025, to December 31, 2030, based on a conclusion that the State has satisfied the requirements for such an extension in section 188(e) of the Act.
The EPA is soliciting public comments on the issues discussed in this document. We will accept comments from the public on this proposal for the next 30 days.
VI. Statutory and Executive Order Reviews
Additional information about these statutes and Executive Orders can be found at https://www.epa.gov/laws-regulations/laws-and-executive-orders.
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
This action is not expected to be an Executive Order 14192 regulatory action because this action is not significant 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
may disproportionately affect children, per the definition of “covered regulatory action” in section 2-202 of the Executive Order. Therefore, this action is not subject to Executive Order 13045 because it merely proposes to approve a State request for an attainment date extension as meeting Federal requirements. Furthermore, the EPA's Policy on Children's Health does not apply to this action.
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, Ammonia, Incorporation by reference, Intergovernmental relations, Nitrogen dioxide, Particulate matter, Reporting and recordkeeping requirements, Sulfur dioxide, Volatile organic compounds.

Authority:
42 U.S.C. 7401 et seq.
Dated: May 29, 2026. Michael Martucci, Acting Regional Administrator, EPA Region IX.

[FR Doc. 2026-11735 Filed 6-10-26; 8:45 am] BILLING CODE 6560-50-P

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/FR_PRORULE_2026-11735. Check the current official text before relying on it. Not legal advice.