SUPPLEMENTARY INFORMATION:

Throughout this document, the use of “we,” “us,” or “our” is intended to refer to the EPA. We use multiple abbreviations and terms in this proposed rule. While this list may not be exhaustive, for ease of reading and for reference purposes, the EPA defines the following terms and abbreviations here:

2016 Ozone Plan—SJVUAPCD and CARB's “2016 Plan for the 2008 8-Hour Ozone Standard”

2016 State SIP Strategy—CARB's 2016 “Revised Proposed State Strategy for the State Implementation Plan”

2018 PM_2.5 Plan—SJVUAPCD and CARB's “2018 Plan for the 1997, 2006, and 2012 PM_2.5 Standards”

2022 State SIP Strategy—CARB's “2022 State Strategy for the State Implementation Plan”

2023 CARB Staff Report—CARB's “Review of the San Joaquin Valley 2022 Plan for the 70 ppb 8-Hour Ozone Standard”

2024 SJV Ozone Contingency Measures Plan—SJVUAPCD and CARB's 2024 “Ozone Contingency Measure State Implementation Plan Revision for the 2008 and 2015 8-Hour Ozone Standards”

2025 ANP—SJVUAPCD's “2025 Air Monitoring Network Plan”

2026 Extreme Ozone SIP Revision—CARB's “2026 State Implementation Plan Revisions for the California Extreme Ozone Nonattainment Areas”

ACF—Advanced Clean Fleets

ACT—Advanced Clean Trucks

BACM—Best Available Control Measures

Budgets—Motor Vehicle Emissions Budgets

CAA—Clean Air Act

CCR—California Code of Regulations

CARB—California Air Resources Board

CEPAM—California Emission Projection Analysis Model

CFFP—Clean Fuels for Fleets Program

CFR—Code of Federal Regulations

CMAQ—Congestion Mitigation and Air Quality

DPR—California Department of Pesticide Regulation

EMFAC—EMission FACtor

EPA—U.S. Environmental Protection Agency

EPA's District Rules and Motor Vehicle Emission Budgets TSD—EPA Region IX, “Technical Support Document, EPA Evaluation of District Control Measures and Transportation Conformity Budgets for the San Joaquin Valley 70 ppb Ozone SIP,” October 2026

EPA's Modeling TSD—EPA Region IX, “Technical Support Document, EPA Review of Attainment Modeling in the San Joaquin Valley 2022 Ozone Plan for the 2015 Ozone NAAQS,” October 2026

ERCs—Emissions Reduction Credits

FHWA—Federal Highway Administration

FR—Federal Register

FSTIP—Federal State Transportation Improvement Program

FTA—Federal Transit Administration

General Preamble—the EPA's “General Preamble for the Implementation of the Clean Air Act Amendments of 1990”

HD I/M Regulation—Heavy-Duty Vehicle Inspection and Maintenance Regulation

Heavy-Duty Warranty Phase 1—Heavy-Duty Warranty Regulations and Maintenance Provisions

I/M—Vehicle Inspection and Maintenance

LDAR—Leak Detection and Repair

MIR—Maximum Incremental Reactivity

Modeling Guidance—the EPA's “Modeling Guidance for Demonstrating Air Quality Goals for Ozone, PM_2.5, and Regional Haze”

MPO—Metropolitan Planning Organization

NAAQS—National Ambient Air Quality Standards

NEI—National Emissions Inventory

NO_X —Oxides of Nitrogen

NSR—New Source Review

Omnibus Low NO_X Program—Heavy-Duty Engine and Vehicle Omnibus Regulation and Amendments ( printed page 69911)

ORVR—Onboard Refueling Vapor Recovery

PAMS—Photochemical Assessment Monitoring Station

Ppm—Parts Per Million

Ppb—Parts Per Billion

PM_2.5 —Particulate Matter Less Than 2.5 µm in Diameter

RACM—Reasonably Available Control Measures

RACT—Reasonably Available Control Measures

RFP—Reasonable Further Progress

ROP—Rate of Progress

RRF—Relative Response Factor

RTP—Regional Transportation Plan

SIP—State Implementation Plan

SJV 2022 Ozone Plan—SJVUAPCD and CARB's “2022 Plan for the 2015 8-Hour Ozone Standard” for the San Joaquin Valley

SJV 70 ppb Ozone SIP—the San Joaquin Valley attainment plan for the 2015 ozone NAAQS (collectively, all or portions of three SIP submissions)

SJVUAPCD or “District”—San Joaquin Valley Unified Air Pollution Control District

SRR—SIP Requirements Rule

SORE—Small Off-Road Engines

Stage II—Gasoline dispensing systems for vehicle refueling vapor recovery

TCM—Transportation Control Measure

TSD—Technical Support Document

VOC—Volatile Organic Compounds

VMT—Vehicle Miles Traveled

WRF—Weather Research and Forecasting

Table of Contents

I. Overview of Proposed Action

A. What action is the EPA taking?

B. What is the legal authority and what are the requirements?

II. EPA Review of the SJV 70 ppb Ozone SIP

A. Background

B. Summary of the State's Submissions for the 2015 Ozone NAAQS in San Joaquin Valley

C. Emissions Inventories

D. Reasonably Available Control Measures Demonstration

E. Attainment Demonstration

F. Rate of Progress Plan and Reasonable Further Progress Demonstration

G. Motor Vehicle Emissions Budgets for Transportation Conformity

H. Other Clean Air Act Requirements Applicable to Extreme Ozone Nonattainment Areas

III. EPA Review of CARB's Consumer Products Regulations

A. Background

B. Summary of the State's Submissions for the Consumer Products Regulations

C. The EPA's Review of the State's Submission

IV. Proposed Action and Public Comment

V. Incorporation by Reference

VI. Statutory and Executive Order Reviews

I. Overview of Proposed Action

A. What action is the EPA taking?

The EPA is proposing to approve certain submitted revisions to the San Joaquin Valley portion of the California SIP for the 2015 ozone NAAQS. We refer to these revisions as the SJV 70 ppb Ozone SIP, and they address the “Extreme” ozone nonattainment area requirements for emissions inventories, reasonably available control measures (RACM), attainment demonstration (including aggregate emission reduction commitments and CAA section 182(e)(5) new technology provisions), rate of progress (ROP) and reasonable further progress (RFP), motor vehicle emissions budgets (“budgets”), and enhanced monitoring. In addition, the EPA is initiating the adequacy review process for the budgets for VOC and NO_X for the 2026, 2029, 2032, and 2035 RFP milestone years and the 2037 attainment year included in the SJV 70 ppb Ozone SIP. For the attainment demonstration, the EPA proposes to approve CARB's aggregate emission reduction commitments for 2037 and CARB's commitment to submit contingency measures by January 1, 2034, to cover any anticipated shortfall in emission reductions to be achieved by the plan's CAA section 182(e)(5) new technology provisions. If the EPA finalizes this proposed action, CARB's aggregate emission reduction commitments and CAA section 182(e)(5) contingency measure commitments would become federally enforceable and transportation conformity demonstrations in the San Joaquin Valley would be required to conform to the regional (whole nonattainment area) motor vehicle emissions budgets for VOC and NO_X for the 2026, 2029, 2032, and 2035 RFP milestone years and the 2037 attainment year.

The EPA is also proposing to approve amendments to the SIP to incorporate changes to California's consumer products regulations and CARB Method 310, which apply statewide. Specifically, the 2021 amendments to CARB's Consumer Products Regulations concern VOC emissions from antiperspirants, deodorants, consumer products, and aerosol coating products, and the 2022 amendments to CARB Method 310 are used to determine the VOC and reactive organic compounds content of these products. If the EPA finalizes this proposed action, the amended Consumer Products Regulations and amended Method 310 would be federally enforceable within the State of California.

We will accept comments from the public for 30 days following publication of this proposal in the Federal Register and will consider relevant comments before taking final action.

B. What is the legal authority and what are the requirements?

The EPA has legal authority to approve, disapprove, or conditionally approve, in whole or in part, submissions of SIPs and SIP revisions under CAA section 110(k). The applicable requirements for the actions proposed by the EPA in this document include those for SIP submissions in general, ozone nonattainment areas, motor vehicle emissions budgets, and enforceable emission limitations.

For SIP submissions in general, CAA sections 110(a)(1) and (2) and 40 CFR 51.102 establish certain procedural requirements with respect to States for adoption and submittal of SIPs and SIP revisions to the EPA to meet CAA requirements. CAA section 110(l) prohibits the EPA from approving SIP revisions that would interfere with any applicable requirements concerning attainment and RFP or any other applicable requirement of the Act.

For SIP submissions addressing ozone nonattainment SIP requirements, the statutory requirements are set forth in CAA sections 171 through 179B of subpart 1 (“Nonattainment Areas in General”) and CAA sections 181 through 185 of subpart 2 (“Additional Provisions for Ozone Nonattainment Areas”) and the regulatory requirements for the 2015 ozone NAAQS are codified in 40 CFR part 51, subpart CC (“Provisions for Implementation of the 2015 Ozone [NAAQS]”). In this document, we refer to these regulatory requirements and related preamble collectively as the 2015 ozone NAAQS SIP Requirements Rule (“2015 Ozone SRR”).^[1] For budgets, the regulatory requirements are codified in 40 CFR 93.118(e) (“Motor vehicle emissions budgets in submitted control strategy State implementation plan revisions and submitted maintenance plans”). More specifically, the budget adequacy criteria are codified in 40 CFR 93.118(e)(4). For more detail on these requirements, as well as background on the EPA's review of the SJV 70 ppb Ozone SIP, see the applicable subsections of section II of this document for emissions inventories, RACM, attainment demonstration, ROP and RFP, motor vehicle emissions budgets, and other requirements.

For SIP submissions related to consumer products and aerosol coatings regulations, the applicable requirements are found in CAA sections 110(a)(2) (“Each such plan shall (A) include enforceable emission limitations . . . (E) provide necessary assurances that ( printed page 69912) the State . . . will have adequate personnel, resources and authority . . .”) and 110(l). In addition, 40 CFR part 51, subpart K (“Source Surveillance”) requires SIPs to have enforceable procedures for monitoring the status of compliance with the requirements in the control strategy. For more detail on these requirements, as well as background on the EPA's review of CARB's Consumer Products Regulations, see section III of this document.

II. EPA Review of the SJV 70 ppb Ozone SIP

A. Background

1. Ozone Standards, Area Designations, and SIPs

Ground-level ozone pollution is formed from the reaction of VOC and oxides of nitrogen (NO_X ) in the presence of sunlight.^[2] These 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 area sources such as residential fuel combustion and farming operations.

Under CAA sections 108 and 109, the EPA promulgates air quality criteria and NAAQS for pervasive air pollutants meeting certain requirements, such as ozone, to protect public health and welfare. Under CAA section 110, following promulgation of a new or revised NAAQS, States are required to adopt and submit plans that provide for implementation, maintenance, and enforcement of the NAAQS (referred to as State Implementation Plans or SIPs). Under CAA section 107(d), the EPA is required to designate areas throughout the nation as either attaining or not attaining the NAAQS, or as unclassifiable. States with designated nonattainment areas are required to submit SIP revisions to, among other things, provide for attainment within the applicable statutory timeline.

In 1979, the EPA established primary and secondary NAAQS for ozone at 0.12 parts per million (ppm) averaged over a 1-hour period (“1979 ozone NAAQS”).^[3] In 1997, the EPA revised the primary and secondary standards for ozone in the ambient air to 0.08 ppm averaged over an 8-hour period (“1997 ozone NAAQS”).^[4]

In 2008, the EPA lowered the 8-hour ozone NAAQS to 0.075 ppm (“2008 ozone NAAQS”).^[5] Then in 2015, the EPA further lowered the 8-hour ozone NAAQS to 0.070 ppm (“2015 ozone NAAQS”).^[6] On December 31, 2020, the EPA finalized its most recent periodic review of the ozone NAAQS, retaining the form and level of the standards.^[7] The EPA has revoked both the 1979 ozone NAAQS and the 1997 ozone NAAQS but not the 2008 ozone NAAQS.^[8]

In 2018, the EPA designated San Joaquin Valley as nonattainment for the 2015 ozone NAAQS and classified the area as Extreme.^[9] The attainment date for areas classified as Extreme for the 2015 ozone NAAQS is as expeditiously as practicable but not later than 20 years from the effective date of the nonattainment designation.^[10] Designations of nonattainment for a given NAAQS trigger requirements under the CAA to prepare and submit SIP revisions. The State of California submitted the SIP revisions that comprise the SJV 70 ppb Ozone SIP and that are the subject of this document to address the Extreme nonattainment area requirements that apply to the San Joaquin Valley for the 2015 ozone NAAQS.

Under California law, CARB is the State agency that is responsible for the adoption and submission to the EPA of California SIP revisions, and it has state-law authority to establish emissions standards and other requirements for mobile sources and certain area sources, such as consumer products. Local and regional air pollution control districts in California are responsible for the regulation of stationary sources and are generally responsible for the development of regional air quality management plans (“plans”). In the San Joaquin Valley, the San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD or “District”) develops and adopts plans to address CAA planning requirements applicable to that area. Such plans are then submitted to CARB for adoption and submission to the EPA as revisions to the California SIP.

Under CAA section 110(k), the EPA is charged with evaluation of each SIP revision submitted by States for compliance with applicable CAA requirements and with taking action on each submission. The EPA evaluates SIP submissions and takes action to approve or disapprove them through notice-and-comment rulemaking, including proposed and final rules published in the Federal Register . Where appropriate, the EPA may act on separate portions of a SIP submission in separate rulemaking actions.

2. The San Joaquin Valley Ozone Nonattainment Area

The San Joaquin Valley nonattainment area for the 2015 ozone standards consists of San Joaquin, Stanislaus, Merced, Madera, Fresno, Tulare, and Kings counties and the western portion of Kern County. The San Joaquin Valley nonattainment area stretches over 250 miles from north to south, averages a width of 80 miles, and encompasses over 23,000 square miles. It is partially enclosed by the Coast Mountain range to the west, the Tehachapi Mountains to the south, and the Sierra Nevada range to the east.^[11] The population of the San Joaquin Valley in 2020 was estimated to be more than 4.4 million people and is projected to increase to nearly 5 million people by 2035.^[12]

B. Summary of the State's Submissions for the 2015 Ozone NAAQS in San Joaquin Valley

In this document, the EPA proposes action on all or portions of three SIP submissions, which we describe in the following paragraphs. Collectively, we refer to the relevant portions of the three SIP submissions as the SJV 70 ppb Ozone SIP.

1. SJV 2022 Ozone Plan

On February 23, 2023, CARB submitted the “2022 Plan for the 2015 8-Hour Ozone Standard” (“SJV 2022 Ozone Plan”) to the EPA as a revision to the California SIP.^[13] The SIP revision includes the SJV 2022 Ozone Plan main document and appendices and CARB's aggregate emissions reduction commitment specified in CARB's Staff ( printed page 69913) Report titled “CARB Review of the San Joaquin Valley 2022 Plan for the 70 ppb 8-Hour Ozone Standard (Hearing Date: January 26, 2023)” (“2023 CARB Staff Report”).^[14]

In addition to the SIP revision, the February 23, 2023 SIP submission includes SJVUAPCD Resolution 22-12-13 (December 15, 2022), through which the District adopted the SJV 2022 Ozone Plan, and CARB Resolution 23-3 (January 26, 2023), through which CARB adopted the SJV 2022 Ozone Plan and its original aggregate emissions reduction commitment (including a subset from on-road mobile source measures for transportation conformity purposes) in support of the attainment demonstration in the SJV 2022 Ozone Plan. The February 23, 2023 SIP submission of the SJV 2022 Ozone Plan also included public process documentation at both the District and CARB levels.

The SJV 2022 Ozone Plan addresses certain nonattainment area SIP requirements for San Joaquin Valley for the 2015 ozone NAAQS. More specifically, the SJV 2022 Ozone Plan includes, among other elements, an updated base year (2017) emissions inventory, RACM demonstration, RFP demonstration, attainment demonstration, motor vehicle emissions budgets for RFP milestone years and the attainment year, and enhanced monitoring. The appendices to the SJV 2022 Ozone Plan provide documentation for the emissions inventories, RACM demonstrations for stationary and mobile sources, and the photochemical modeling conducted in support of the attainment demonstration.

The attainment demonstration in the SJV 2022 Ozone Plan relies on the 2022 State SIP Strategy and the aggregate emissions reductions commitment by CARB. We further describe the 2022 State SIP Strategy in section II.B.2 of this document. Also, since the submission of the SJV 2022 Ozone Plan, the District and CARB have replaced or updated certain elements of the plan, including the future year emissions inventories, attainment control strategy and associated commitments, the RFP demonstration, the motor vehicle emissions budgets, and the contingency measure elements, as discussed further below.

2. 2022 State SIP Strategy

On February 23, 2023, CARB submitted the “2022 State Strategy for the State Implementation Plan” (“2022 State SIP Strategy”) to the EPA as a revision to the California SIP.^[15] The SIP revision for the 2022 State SIP Strategy includes the main document itself plus CARB's resolution of adoption of the 2022 State SIP Strategy (CARB Resolution 22-14). Considered together, the 2022 State SIP Strategy and CARB Resolution 22-14 originally committed the State of California to pursue 19 new SIP measures or otherwise address each measure as described in the 2022 State SIP Strategy by the dates specified in an attachment to CARB Resolution 22-14.^[16] The overall 2022 State SIP Strategy combines the commitment to pursue certain new SIP measures on a specified schedule with an aggregate emissions reduction commitment for individual nonattainment areas made at the time CARB adopted attainment plans for the individual areas. In the case of the San Joaquin Valley for the 2015 ozone NAAQS, CARB's original aggregate emissions reductions commitment was made through CARB Resolution 23-3 adopting the SJV 2022 Ozone Plan.

3. 2026 Extreme Ozone SIP Revision

On September 23, 2026, CARB submitted the “2026 State Implementation Plan Revisions for the California Extreme Ozone Nonattainment Areas” (“2026 Extreme Ozone SIP Revision”) to the EPA as a revision to the California SIP.^[17] CARB adopted the 2026 Extreme Ozone SIP Revision on July 23, 2026. The 2026 Extreme Ozone SIP Revision includes revisions to the future year emissions inventories, attainment demonstration and associated commitments, RFP demonstration, and motor vehicle emissions budgets in the SJV 2022 Ozone Plan. The budgets in the SJV 2022 Ozone Plan were derived from EMFAC2017 and the budgets in the 2026 Extreme Ozone SIP Revision are intended to update the EMFAC2017-derived budgets with revised budgets derived from the most recent EPA-approved motor vehicle emissions model for California, i.e., EMFAC2021, with off-model adjustment factors accounting for Congress' enactment of statutes disapproving the waivers of preemption previously issued by the EPA for certain CARB mobile source regulations ^[18] and adjustment factors accounting for the EPA's partial approval and partial disapproval of CARB's Heavy-Duty Vehicle Inspection and Maintenance Regulation (“HD I/M Regulation”).^[19] The 2026 Extreme Ozone SIP Revision also includes revisions to the 2022 State SIP Strategy and revisions to the control strategy and RFP demonstration from the SJV 2022 Ozone Plan to reflect the updated budgets. The 2026 Extreme Ozone SIP Revision includes revisions for other nonattainment area plans, but in this document, we propose action only on the 2026 Extreme Ozone SIP Revision as it pertains to the San Joaquin Valley for the 2015 ozone NAAQS.

4. Clean Air Act Procedural Requirements for Adoption and Submission of SIP Revisions

CAA sections 110(a) and 110(l) require a State to provide reasonable public notice and opportunity for public hearing prior to the adoption and submission of a SIP or SIP revision. To meet this requirement, every covered SIP submission should include evidence that adequate public notice was given and an opportunity to submit written comments and request a public hearing was provided consistent with the EPA's implementing regulations in 40 CFR 51.102.

Both the District and CARB have satisfied the applicable statutory and regulatory requirements for reasonable public notice and hearing prior to the adoption and submission of the SJV 2022 Ozone Plan, the 2022 State SIP Strategy, and the 2026 Extreme Ozone SIP Revision. With respect to the SJV 2022 Ozone Plan, the District conducted ( printed page 69914) six public workshops on the draft SJV 2022 Ozone Plan.^[20] On November 15, 2022, the District provided notice of an opportunity to submit written comments and notice of a public hearing to be held on December 15, 2022, for the adoption of the proposed SJV 2022 Ozone Plan. On December 15, 2022, the District held the public hearing, and, through Resolution 22-12-13, adopted the SJV 2022 Ozone Plan.

CARB also provided the public notice and opportunity for public comment on the SJV 2022 Ozone Plan. On December 16, 2022, CARB released for public review and comment the 2023 CARB Staff Report and published a notice of public meeting to be held on January 26, 2023, to consider approval of the SJV 2022 Ozone Plan and the related aggregate emissions reduction commitment as described in the 2023 CARB Staff Report. On January 26, 2023, CARB held the hearing and approved the SJV 2022 Ozone Plan and 2023 CARB Staff Report through CARB Resolution 23-3. On February 23, 2023, the Executive Officer of CARB submitted the SJV 2022 Ozone Plan and 2023 CARB Staff Report to the EPA as a revision of the California SIP and included the transcript of the public hearing.

With respect to the 2022 State SIP Strategy, CARB conducted three public workshops on the Draft 2022 State SIP Strategy.^[21] On August 12, 2022, CARB circulated for public review and comment the proposed 2022 State SIP Strategy and provided notice of a public hearing by the CARB Board to be held on September 22, 2022. On September 22, 2022, through Resolution 22-14, CARB adopted the 2022 State SIP Strategy and the commitment to pursue new SIP measures or otherwise address each measure as described in the 2022 State SIP Strategy by the dates specified in Attachment A to Resolution 22-14. On February 23, 2023, CARB submitted the 2022 State SIP Strategy to the EPA as a revision to the California SIP and included the transcript of the public hearing.

With respect to 2026 Extreme Ozone SIP Revision, on April 17, 2026, CARB provided notice of opportunity to submit written comments and notice of a public hearing to be held on May 28, 2026, for adoption of the proposed 2026 Extreme Ozone SIP Revision. On May 18, 2026, CARB posted errata to correct transcription errors in the 2026 Extreme Ozone SIP Revision, and on May 27, 2026, and June 12, 2026, CARB rescheduled the public hearing to July 23, 2026, and extended the comment period to July 13, 2026. CARB held the public hearing and adopted the 2026 Extreme Ozone SIP Revision, through Resolution 26-5, on July 23, 2026. On September 23, 2026, CARB submitted the 2026 Extreme Ozone SIP Revision to the EPA as a revision of the California SIP and included the transcript of the public hearing.

Based on information provided in each SIP revision and summarized herein, the EPA has determined that CARB and the District provided for the required opportunities for public participation in the development and adoption of the SIP revisions that comprise the SJV 70 ppb Ozone SIP. Therefore, we propose to find that the submissions that comprise the SJV 70 ppb Ozone SIP ( i.e., the SJV 2022 Ozone Plan, the 2022 State SIP Strategy, and the 2026 Extreme Ozone SIP Revision) meet the procedural requirements for public notice and hearing in CAA sections 110(a) and 110(l) and 40 CFR 51.102.

C. Emissions Inventories

1. Statutory and Regulatory Requirements

CAA sections 172(c)(3) and 182(a)(1) require States to submit for each ozone nonattainment area a “base year inventory” that is a comprehensive, accurate, current inventory of actual emissions from all sources of the relevant pollutant or pollutants in the area. Emissions inventories for ozone must include emissions of VOC and NO_X and represent emissions for a typical ozone season weekday.^[22] States should include documentation explaining how the emissions data were calculated. In estimating mobile source emissions, States should use the latest emissions models and planning assumptions available at the time the SIP is developed.^[23]

Future year projected emissions inventories must reflect the most recent population, employment, travel, and congestion estimates for the area. Projected inventories will reflect the net effect of emissions resulting from anticipated changes in future activity (such as emissions increases due to growth in vehicle miles traveled (VMT)); emission decreases due to implementation of existing requirements for stationary source and car/truck emissions; and the effects of new control measures needed to reduce emissions and bring nonattainment areas and States into compliance with a particular SIP requirement.^[24] Both the base year and future year inventories are necessary for the RFP demonstration and photochemical modeling to demonstrate attainment.

On July 27, 2020, CARB submitted the base year (2017) emissions inventories for certain nonattainment areas, including San Joaquin Valley, for the 2015 ozone NAAQS. In 2022, the EPA approved the base year emissions inventory for San Joaquin Valley for the 2015 ozone NAAQS as meeting the requirements of CAA sections 172(c)(3) and 182(a)(1) and 40 CFR 51.1315.^[25]

2. Summary of the State's Submission

The SJV 2022 Ozone Plan includes an updated emissions inventory for the base year (2017) and emissions projections for calendar years 2022 through the 2037 attainment year.^[26] The updated base year and future year projected emissions inventories in the SJV 2022 Ozone Plan are presented in terms of average ozone season tons per day (tpd). With respect to the base year emissions inventories, the differences between the approved base year emissions inventory and the updated base year emissions inventory in the SJV 2022 Ozone Plan primarily relate to the emissions estimates for trains, recreational boats, and off-road equipment.^[27]

Documentation for the inventories is found in Appendix B of the SJV 2022 Ozone Plan. Because ozone levels in the area are typically highest during the summer months, the inventories represent average summer day emissions from May through October. The inventories in Appendix B reflect District and CARB rules adopted through the end of calendar year 2021. The future year emissions inventories documented in Appendix B of the SJV 2022 Ozone Plan are referred to as “baseline” future year emissions inventories to distinguish them from other future year emissions inventories. ( printed page 69915)

Baseline future year emissions inventories correspond to the anthropogenic emissions sources within the nonattainment area, reflect regulations adopted by the time of plan development, and are used for the RFP demonstration. The SJV 2022 Ozone Plan also includes other future year emissions inventories, including the modeled attainment emissions inventory for the nonattainment area, which is similar to the baseline future year emissions inventory except that it also reflects emissions reductions that the State has committed to achieve. The emissions inventories developed for modeling purposes are similar to the other emissions inventories, but they include nonanthropogenic emissions sources and cover a geographic area larger than the nonattainment area.

The VOC and NO_X emissions estimates are grouped into two general categories, stationary sources and mobile sources. Stationary sources are further divided into “point” and “area” sources. Point sources typically refer to stationary sources that are permitted facilities and have one or more identified and fixed pieces of equipment and emissions points. Area sources consist of widespread and numerous smaller emissions sources, such as residential fuel combustion, managed burning and disposal, farming operations, consumer products, pesticides, and architectural coatings.^[28] Mobile sources are divided into two major subcategories, “on-road” and “off-road” mobile sources. On-road mobile sources include, among other vehicle classifications, light-duty automobiles; light-, medium-, and heavy-duty trucks; and motorcycles. Off-road mobile sources include farm equipment, off-road equipment (such as construction equipment), locomotives, portable equipment, recreational boats, aircraft, fuel storage and handling, and recreational vehicles.

Emissions from point sources (also referred to as “stationary sources”) for the 2017 base year emissions inventory are calculated using data from facilities using the District's annual emissions reporting program. Under this program, the District requests annual emissions inventories from all permitted sources in the San Joaquin Valley. The District sends each permitted facility an inventory statement or inventory survey form. An emissions inventory statement is required for those facilities that have actual annual emissions of greater than or equal to 25 tons of VOC or NO_X and an emissions inventory survey form is required for sources that have potential annual emissions less than 25 tons.^[29]

Stationary point sources also include smaller point sources, such as gasoline dispensing facilities, that are not inventoried individually but are estimated as a group and reported as a single source category. Emissions from these sources are estimated using various models and methodologies.^[30] Area sources include smaller emissions sources distributed across the nonattainment area. CARB and the District estimate emissions for numerous area source categories using established inventory methods, including publicly available emissions factors and activity information.^[31]

On-road emissions inventories in the SJV 2022 Ozone Plan are calculated using CARB's EMFAC2017 model, the EPA-approved version of California's motor vehicle emissions model available at the time of plan development,^[32] and the travel activity data (VMT and speed distributions) provided by the eight county-based metropolitan planning organizations (MPOs) in the San Joaquin Valley from their 2019 Federal Statewide Transportation Improvement Program (FSTIP) amendments.^[33] Off-road emissions inventories are estimated using specific models for several source categories and OFFROAD2007 for all other source categories.^[34]

CARB used the California Emission Projection Analysis Model (CEPAM), 2019 SIP Baseline Emission Projections, Version 1.04 (“CEPAM2019 version 1.04”) to develop future year emissions forecasts ( i.e., RFP milestone years of 2023, 2026, 2029, 2032, and 2035, and attainment year of 2037). In doing so, CARB and the District reviewed the inventory for accuracy of point source emissions reports, use of the most recently approved models and methodologies for mobile and area sources, and growth and control profiles for point source and area source categories, and updated them to reflect trends, current conditions, and recent economic and demographic forecasts.^[35]

With respect to on-road mobile sources, CEPAM2019 version 1.04 incorporated output from EMFAC2017 but also included emissions reductions attributable to certain CARB regulations adopted after development of EMFAC2017 but before submission of the SJV 2022 Ozone Plan. These regulations originally included California's Advanced Clean Trucks (ACT) Regulation, Heavy-Duty Vehicle and Engine Emission Warranty and Maintenance Provisions (“Heavy-Duty Warranty Phase 1”), Zero-Emission Airport Shuttle Regulation, Heavy-Duty Engine and Vehicle Omnibus Regulation and Amendments (“Omnibus Low NO_X Program”), and CARB's HD I/M Regulation (also referred to as California's “Clean Truck Check” program).

In the 2026 Extreme Ozone SIP Revision, CARB revised the on-road emissions inventories from the SJV 2022 Ozone Plan to reflect developments that occurred since adoption of the SJV 2022 Ozone Plan. Specifically, CARB developed a revised version of CEPAM2019 version 1.04 that takes into account Congress' enactment of statutes disapproving the waivers of preemption previously issued by the EPA for California's ACT Regulation, Heavy-Duty Warranty Phase 1,^[36] Zero-Emission Airport Shuttle Regulation, and Omnibus Low NO_X Program ^[37] by ( printed page 69916) removing the emissions reductions attributable to those regulations.^[38] CARB also revised CEPAM2019 version 1.04 to reflect the EPA's partial disapproval of California's HD I/M Regulation by removing the emissions reductions attributable to implementation of the program to vehicles registered out-of-state and out-of-country (“out-of-state vehicles”).

The 2026 Extreme Ozone SIP Revision did not revise the base year (2017) emissions inventory or the future year emissions projections prepared for the SJV 2022 Ozone Plan for the other major source categories, including stationary and area-wide sources and off-road (nonroad) vehicles and equipment.

The calendar year 2017 is the base year in the SJV 2022 Ozone Plan because 2017 was the most recent calendar year for which a complete triennial inventory was required to be submitted to the EPA under the provisions of 40 CFR part 51, subpart A, at the time of plan development. The 2017 base year inventory was used to forecast all future year emissions for stationary, area, and mobile sources.^[39]

The future year emission estimates in the SJV 2022 Ozone Plan include additional, specific adjustments to account for pre-base year emissions reduction credits (ERCs). Under the EPA's SIP regulations for nonattainment new source review (NSR) programs, a State may allow new major stationary sources or major modifications to use as offsets ERCs that were generated through shutdown or curtailed emissions units occurring before the base year of an attainment plan. However, to use such ERCs, the projected emissions inventories used to develop the RFP and attainment demonstration must explicitly include the emissions from such previously shutdown or curtailed emissions units.^[40]

The District has elected to provide for use of pre-base year ERCs as offsets through an evaluation of the amount of such offsets expected to be used through 2037 relative to the general growth in emissions for the relevant stationary source categories that is included in future year emissions inventories developed using CEPAM.^[41] With respect to VOC, the District expects that general VOC growth included in CEPAM is sufficient to account for the magnitude of pre-baseline VOC ERC usage that is forecasted to be used through 2037. As for NO_X, the District concludes that the general NO_X growth included in CEPAM is not sufficient to account for the magnitude of pre-baseline NO_X ERC usage that is expected to be used through 2037. As such, the District added an additional pre-baseline NO_X ERC usage tonnage of 2.43 tpd to the plan by factoring the additional tonnage into the RFP and attainment demonstrations.^[42 43] Moreover, the District has adopted a cap on the amount of pre-baseline ERCs that can be used through 2037 to assure that the use of pre-baseline ERCs does not interfere with RFP or attainment.^[44]

Table 1 of this document provides a summary of the baseline emissions inventories for the base year and future years in tpd (average summer day) for VOC and NO_X for the 2015 ozone NAAQS.^[45] Based on the emissions inventory for 2017, the largest VOC emission sources are area sources, followed by stationary sources, off-road mobile sources, and finally on-road mobile sources, and the largest NO_X emission sources are on-road and off-road mobile sources, followed by stationary sources, and finally area sources. A comparison of the base year with the future years shows the substantial decrease that is expected to be achieved through CARB's regulations for on-road and off-road mobile sources together with vehicle turnover ( i.e., the replacement of older, more polluting models with new models manufactured to meet tighter emissions standards). For a more detailed discussion of the methodologies used to develop the inventories, see Appendix B of the SJV 2022 Ozone Plan and pages 39 through 40 of the 2026 Extreme Ozone SIP Revision.

( printed page 69917)

3. The EPA's Review of the State's Submission

As noted previously, the EPA approved the base year emissions inventory for San Joaquin Valley for the 2015 ozone NAAQS in 2022. We are reviewing the updated base year emissions inventory in the SJV 2022 Ozone Plan to ensure that it continues to meet the requirements of CAA sections 172(c)(3) and 182(a)(1) and 40 CFR 51.1315.

We have reviewed the 2017 base year emissions inventory in the SJV 2022 Ozone Plan and the inventory methodologies used by the District and CARB for consistency with CAA requirements and EPA guidance. First, we find that the 2017 inventory includes estimates for VOC and NO_X for a typical ozone season weekday and that CARB and the District have provided adequate documentation explaining how the emissions are calculated. Second, we find that the 2017 base year emissions inventory in the SJV 2022 Ozone Plan reflects appropriate emissions models and methodologies and, therefore, represents a comprehensive, accurate, and current inventory of actual emissions during that year in the San Joaquin Valley. Therefore, the EPA proposes to approve the 2017 emissions inventory in the SJV 2022 Ozone Plan as meeting the requirements for base year inventories for the 2015 ozone NAAQS set forth in CAA sections 172(c)(3) and 182(a)(1) and 40 CFR 51.1315.

With respect to the future year baseline emissions inventories, we have reviewed the growth and control factors and find them acceptable and conclude that the future baseline emissions inventories in the SJV 2022 Ozone Plan, as revised by the 2026 Extreme Ozone SIP Revision, reflect appropriate calculation methods and the latest planning assumptions. We have reviewed the documentation for the ERCs and find that they are appropriately accounted for in the future year baseline emissions inventories as an off-model adjustment to the inventories. Moreover, we recognize the District's adoption of a cap on the amount of pre-baseline ERCs that can be used through 2037 as providing further assurance that the use of pre-baseline ERCs does not interfere with RFP or attainment of the 2015 ozone NAAQS in the San Joaquin Valley.

Also, as a general matter, the EPA will approve a SIP revision that takes emissions reduction credit for a control measure only where the EPA has approved the measure as part of the SIP. Thus, to take credit for the emissions reductions from District and CARB rules for stationary, area, and mobile sources, those rules must be approved by the EPA into the SIP.^[46] The EPA performed a review of District and CARB rules relied upon in developing the future baseline emissions inventories for the SJV 2022 Ozone Plan, as revised by the 2026 Extreme Ozone SIP Revision.^[47] Based on our review, we find that most of the rules relied upon in developing the future baseline emissions inventories are approved as part of the SIP.^[48] However, there are several exceptions where EPA action is pending on SIP submissions of District and CARB rules that are relied upon in the future baseline emissions inventories. We discuss these exceptions in further detail in sections II.E (regarding the attainment demonstration) and II.F (regarding the RFP demonstration) of this document.

Broadly speaking, we therefore propose to find that the future year baseline emissions inventories in the SJV 2022 Ozone Plan, as revised by the 2026 Extreme Ozone SIP Revision, are properly supported by SIP-approved stationary, area, and mobile source measures.

D. Reasonably Available Control Measures Demonstration

1. Statutory and Regulatory Requirements

CAA section 172(c)(1) requires that each attainment plan provide for the implementation of all RACM as expeditiously as practicable (“including such reductions in emissions from existing sources in the area as may be obtained through the adoption, at a minimum, of reasonably available control technology (RACT)”), and to provide for attainment of the NAAQS. The 2015 Ozone SRR requires that, for each nonattainment area required to submit an attainment demonstration, the State concurrently submit a SIP revision demonstrating that it has adopted all RACM necessary to demonstrate attainment as expeditiously as practicable and to meet any RFP requirement.^[49]

The EPA has previously provided guidance interpreting the RACM requirement in the “General Preamble for the Implementation of the Clean Air Act Amendments of 1990” (“General Preamble”) and in a memorandum entitled “Guidance on the Reasonably Available Control Measure Requirement and Attainment Demonstration Submissions for Ozone Nonattainment Areas.” ^[50] In short, to address the requirement to adopt all RACM, States should consider all potentially reasonable measures for source categories in the nonattainment area to determine whether they are reasonably available for implementation in that area and whether they would, if implemented individually or collectively, advance the area's attainment date by one year or more.^[51]

For ozone nonattainment areas classified as “Moderate” or above, CAA section 182(b)(2) also requires implementation of RACT for all major sources of VOC and for each VOC source category for which the EPA has issued control techniques guidelines. CAA section 182(f) requires that RACT under CAA section 182(b)(2) also apply to major stationary sources of NO_X . In Extreme areas, a major source is a stationary source that emits or has the potential to emit at least 10 tpy of VOC or NO_X (CAA sections 182(e) and (f)). Under the 2015 Ozone SRR, States were required to submit SIP revisions meeting the RACT requirements of CAA sections 182(b)(2) and 182(f) no later than 24 months after the effective date of designation for the 2015 ozone NAAQS. Implementation of the required RACT measures is required as expeditiously as practicable but no later than January 1 of the 5th year after the effective date of designation for the 2015 ozone NAAQS ( see40 CFR 51.1312(a)).^[52]

( printed page 69918)

2. Summary of the State's Submission

For the SJV 2022 Ozone Plan, the District, CARB, and the local MPOs each undertook a process to identify and evaluate potential RACM that could contribute to expeditious attainment of the 2015 ozone NAAQS in the San Joaquin Valley. We describe each agency's process below.

a. District's RACM Analysis

The District's RACM demonstration and control strategy for the 2015 ozone NAAQS focuses on stationary and area source controls and is described in Chapter 3 and Appendix C of the SJV 2022 Ozone Plan. To identify potential RACM, the District reviewed 60 District rules for the wide array of emission source categories in the San Joaquin Valley and compared those measures against Federal requirements and regulations implemented by the State and other air districts.

Prior to the adoption of the SJV 2022 Ozone Plan, the District developed and implemented comprehensive plans to provide for attainment of the NAAQS for particulate matter less than 2.5 µm in diameter (PM_2.5) ( e.g., the “2018 Plan for the 1997, 2006, and 2012 PM_2.5 Standards” (“2018 PM_2.5 Plan”)) and ozone ( e.g., the “2016 Plan for the 2008 8-Hour Ozone Standard” (“2016 Ozone Plan”)).^[53] These plans have resulted in the District's adoption of many new rules and amendments to existing rules for stationary and area sources, including amendments to District rules for flares; large boilers, steam generators, and process heaters; solid fuel-fired boilers, steam generators, and process heaters; glass melting furnaces; internal combustion engines; and woodburning fireplaces and heaters.

Table 2 identifies the District control measures, as listed in Table 3-1 of the SJV 2022 Ozone Plan, that contribute to attainment of the 2015 ozone NAAQS by 2037 and the dates on which CARB submitted the measure or, if applicable, the EPA approved the measure. As shown in Table 2, the EPA has approved most of these measures into the California SIP.

The District's RACM evaluation in Appendix C of the SJV 2022 Ozone Plan provides the following for each rule reviewed:

• Base year and projected baseline emissions for the affected source category;
• Description of the affected sources and discussion of the current requirements of the rule, including any recent amendments as of the plan's development;
• Discussion of potential additional control measures, including, in many cases, a discussion of the technological and economic feasibility of the additional control measures. This includes comparison of each District rule to analogous control measures adopted by other agencies (including the EPA, the State, and other air districts such as Bay Area Air Quality Management District, South Coast Air Quality Management District, Sacramento Metropolitan Air Quality Management District, and Ventura County Air Pollution Control District); ( printed page 69919)
• Statement of whether potential additional control measures would be available and appropriate for contingency measure requirements; and
• A summary of the District's findings.

Based on its evaluation, the District concludes that it is implementing all RACM for sources under the District's jurisdiction.

b. CARB's RACM Analysis

Chapter 5, subchapter 5.3.2 and Appendix D of the SJV 2022 Ozone Plan contain CARB's evaluation of mobile source and other statewide control measures that reduce emissions of NO_X and VOC in the San Joaquin Valley. Source categories for which CARB has primary responsibility for reducing emissions in California include most new and existing on- and off-road engines and vehicles, motor vehicle fuels, and consumer products. The California Department of Pesticide Regulation (DPR) is responsible for regulating the application of pesticides, which is a significant source of VOC emissions in the San Joaquin Valley.

Given the need for substantial emissions reductions from mobile and area sources to meet the NAAQS in California nonattainment areas, the State has developed stringent control measures for on-road and off-road mobile sources and the fuels that power them. CAA section 209(a) includes a broad preemption provision, which states that “[n]o State or any political subdivision thereof shall adopt or attempt to enforce any standard relating to the control of emissions from new motor vehicles or new motor vehicle engines.” However, Congress provided an exception in CAA section 209(b), under which California can obtain a waiver of preemption from the EPA if certain statutory conditions are met. Under CAA section 209(e)(2)(A), California may similarly seek and obtain a waiver of preemption, also called an authorization, from the EPA to adopt and enforce standards and other requirements related to the control of emissions from nonroad vehicles or engines, with certain exceptions, if certain statutory conditions are met. The EPA has approved mobile source regulations for which waivers or authorizations have been issued as revisions to the California SIP.^[54]

CARB's mobile source program extends beyond regulations that are subject to the preemption and waiver or authorization process set forth in CAA section 209, including standards and other requirements to control emissions from in-use heavy-duty trucks and buses and gasoline and diesel fuel specifications.^[55] Generally, these regulations have been submitted and approved as revisions to the California SIP.^[56]

In addition, CARB presents its RACM analysis of area source programs under the jurisdiction of State agencies, such as those for VOC emissions from consumer products (including CARB's Consumer Products Regulations adopted through 2021) and pesticide application (including DPR's regulations adopted through 2013 that apply in the San Joaquin Valley).^[57] Similarly, these regulations have been submitted and approved as revisions to the California SIP.^[58]

The State concludes that, in light of the comprehensiveness and stringency of the State's mobile and area source programs, all RACM for mobile and area sources under CARB's and DPR's jurisdictions are being implemented, and that no additional reasonably available measure would advance attainment of the 2015 ozone NAAQS by at least a year.

c. Local Jurisdictions' RACM Analysis and Transportation Control Measures

Chapter 5, subchapter 5.3.3 and section D.3.4 and Attachment A of Appendix D of the SJV 2022 Ozone Plan contain the evaluation of transportation control measures (TCMs) for all the San Joaquin Valley MPOs, building upon analyses prepared in the development of the MPOs' 2022 Regional Transportation Plans (RTPs) and 2023 FSTIPs. These RTP and FSTIP amendments were developed in consultation with Federal, State, and local transportation and air quality planning agencies and other stakeholders. The MPOs already implement many of the TCMs identified in CAA section 108(f) through planning efforts such as the Congestion Mitigation and Air Quality (CMAQ) cost effectiveness policy that the MPOs adopted in 2007. While the MPOs found that the selected TCMs contribute to the SJV air quality attainment goals, they also state that the emission reductions from such TCMs were too small or impossible to quantify and they conclude that such TCMs would therefore not advance the attainment date.^[59]

As part of its overall RACM conclusion, the State concludes that all RACM are being implemented in the San Joaquin Valley, inclusive of the local TCMs, and that there are no additional RACM under each agency's jurisdiction that would advance attainment by one year or contribute to RFP in the San Joaquin Valley.

3. The EPA's Review of the State's Submission

The EPA has reviewed the RACM demonstration in the SJV 2022 Ozone Plan for stationary, area, and mobile sources of NO_X and VOC in the San Joaquin Valley, including the processes, analyses, and conclusions presented by the District, CARB, and MPOs with respect to sources under their jurisdictions, as described in the following paragraphs. We provide additional detail on many of the District's control measures for stationary and area sources in the EPA's “Technical Support Document, EPA Evaluation of District Control Measures and Transportation Conformity Budgets for the San Joaquin Valley 70 ppb Ozone SIP,” October 2026 (“EPA's District Rules and Motor Vehicle Emissions Budgets TSD”).

The process the District used in the SJV 2022 Ozone Plan to identify RACM is generally consistent with the EPA's recommendations in the General Preamble. The process included compiling a comprehensive list of potential control measures for sources of NO_X and VOC in the San Joaquin Valley.^[60] As part of this process, the District evaluated potential controls for all relevant source categories for economic and technological feasibility and provided justifications for the rejection of certain identified measures. The District concluded in its RACM evaluation that no additional measures could advance attainment by one year.

We have reviewed the District's determination in the SJV 2022 Ozone Plan that its stationary and area source ( printed page 69920) control measures represent RACM for NO_X and VOC. In our review, we also considered our previous evaluations of the District's rules in connection with our approval of the RACM demonstration for the San Joaquin Valley for the 2008 ozone NAAQS and the approval of the demonstrations of best available control measures (BACM) and most stringent measures (MSM) for NO_X for the San Joaquin Valley for the PM_2.5 NAAQS.^[61]

The District's rules providing for the implementation of RACM for the 2015 ozone NAAQS are accounted for in the plan's baseline control strategy and have been approved by the EPA into the California SIP, except for the most recent amendments to District Rules 4306/4320, 4352, 4354, 4702, and 4905.

The District's RACM evaluation refers to the most recent amendments of these rules as meeting or exceeding the RACT or RACM requirement, as applicable, and thus, we have reviewed the amended rules to determine whether their approval is necessary to meet the requirement or goes beyond the requirement. For the following reasons, we find that we do not need to approve the most recent amendments to District Rules 4306/4320, 4352, 4354, 4702, and 4905 to propose approval of the RACM demonstration for the San Joaquin Valley for the 2015 ozone NAAQS:

• All of these rules establish emission limits for NO_X , and the EPA approved the District rules as meeting the more stringent BACM requirement in 2023 based on the previous versions of the rules that are approved into the SIP; ^[62]
• The District's RACT demonstration for the 2015 ozone NAAQS relies on the previous version of the rules that are approved into the SIP and not the most recent amendments; ^[63]
• The most recent amendments of District Rules 4306/4320,^[64] 4352,^[65] 4354,^[66] and 4702 ^[67] were not adopted for the purpose of meeting the RACT/RACM requirement for ozone but rather for the purpose of providing for attainment of the PM_2.5 NAAQS by the applicable attainment dates; and
• The most recent amendments to District Rule 4905 were intended to extend the implementation period for certain unit types as a response to the limited number of certified compliant units available by the compliance deadline dates,^[68] which means the 2015 version of the rule that is approved into the SIP continues to meet the RACM requirement.

We recognize that emissions reductions from the most recent amendments are included in the baseline emissions estimates used for the RFP and attainment demonstrations for the 2015 ozone NAAQS. Because we cannot credit the emissions reductions from rules or amendments that we have not yet approved, we have taken the foregone emissions reductions into account in our evaluation of the future baseline emissions inventories and the associated RFP and attainment demonstrations, as described in sections II.E.3 and II.F.3 of this document. The emission reductions included under CAA section 182(e)(5) new technology provisions are 32.4 tpd NO_X in 2037, which is approximately ten times the emission reductions estimated for the most recent amendments to District Rules 4306/4320, 4352, 4354, 4702, and 4905.

Given the larger overall reductions needed to attain by 2037, the emissions reductions from the most recent amendments of the rules would serve only to reduce the reductions expected from new technology provisions rather than to advance the attainment date. Furthermore, the emissions from these rules are not necessary to meet the RFP requirements. Because the emissions reductions associated with the most recent amendments would not advance the attainment date nor are they needed to meet the RFP requirements, we do not need to approve the most recent amendments as part of the SIP to propose approval of the submitted RACM demonstration.

With respect to mobile sources and other sources under CARB's primary jurisdiction, CARB has developed and implements stringent control measures for on-road and off-road mobile sources, and its current program addresses the full range of mobile sources in the San Joaquin Valley through regulatory programs for certain aspects of both new and in-use vehicles. With respect to pesticides under DPR's jurisdiction, DPR has developed regulations to limit VOC emissions from agricultural and commercial structural pesticides, including fumigant and non-fumigant pesticides, that are applied in the San Joaquin Valley. CARB's and DPR's rules providing for the implementation of RACM for the 2015 ozone NAAQS are accounted for in the SJV 2022 Ozone Plan's baseline control strategy and have been approved into the California SIP, with several exceptions described in section II.E.3 of this document.

With respect to TCMs, the current TCMs implemented by the San Joaquin Valley MPOs, including those selected from the MPOs' 2021 review of TCMs, are reflected in each MPO's 2022 RTP and 2023 FSTIP. The 2022 RTPs and 2023 FSTIPs were adopted by the MPOs in July to September 2022 and approved by the Federal Highway Administration on December 16, 2022.^[69] We find that the MPOs' process for identifying additional TCM RACM and their conclusions that the TCMs being implemented in the San Joaquin Valley ( i.e., the TCMs in their 2022 RTPs and 2023 FSTIPs and described in section D.3.4 and Attachment A of Appendix D of the SJV 2022 Ozone Plan) represent all TCM RACM to be reasonably justified and supported.

Based on our review of the District's RACM determination in the SJV 2022 Ozone Plan and our analysis of the several District rules where EPA action is pending on the latest rule amendments, as discussed herein, we propose to find that the District's rules provide for the implementation of RACM for stationary and area sources of NO_X and VOC in the San Joaquin Valley for the 2015 ozone NAAQS. Similarly, we find that the programs developed and administered by CARB for mobile ( printed page 69921) sources and consumer products, by DPR for pesticides, and by the MPOs for TCMs provide for the implementation of RACM for applicable sources of NO_X and VOC in the San Joaquin Valley for the 2015 ozone NAAQS.

Overall, based on our review of the plan's RACM demonstrations for stationary, area, and mobile sources of NO_X and VOC, we agree with the State, District, and MPOs' conclusions that there are no additional reasonably available measures that would advance attainment of the 2015 ozone NAAQS in the San Joaquin Valley by at least one year.^[70] We also find that no additional reasonably available TCMs are needed to demonstrate RFP. For the foregoing reasons, we propose to find that the SJV 2022 Ozone Plan, as revised by the 2026 Extreme Ozone SIP Revision, provides for the implementation of all RACM as required by CAA section 172(c)(1) and 40 CFR 51.1312(c).

E. Attainment Demonstration

1. Statutory and Regulatory Requirements

CAA section 182(c)(2)(A) requires that a plan for an ozone nonattainment area classified “Serious” or above include a “demonstration that the plan . . . will provide for attainment of the ozone [NAAQS] by the applicable attainment date. This attainment demonstration must be based on photochemical grid modeling or any other analytical method determined . . . to be at least as effective.” The attainment demonstration predicts future ambient concentrations for comparison to the NAAQS, making use of available information on measured concentrations, meteorology, and current and projected emissions inventories of ozone precursors, including the effect of control measures in the plan.

Areas classified Extreme for the 2015 ozone NAAQS must demonstrate attainment as expeditiously as practicable, but no later than 20 years after the effective date of designation to nonattainment. The San Joaquin Valley was designated nonattainment for the 2015 ozone NAAQS, effective August 3, 2018.^[71] Accordingly, the area must demonstrate attainment of the 2015 ozone NAAQS as expeditiously as practicable, but no later than August 3, 2038.^[72] An attainment demonstration must show attainment of the standards by the ozone season prior to the attainment date, so in practice, Extreme nonattainment areas must demonstrate attainment no later than 2037 for the 2015 ozone NAAQS.

An attainment demonstration consists of: (1) Technical analyses, such as base year and future year modeling, to identify sources of emissions that are contributing to violations of the ozone NAAQS within the nonattainment area; (2) analyses of future year emissions reductions and air quality improvement resulting from existing ( i.e., already-adopted or “on the books”) Federal, State, and local programs and potential additional State and local measures needed for attainment, including RACM and RACT for the area; (3) a list of adopted measures (including RACT) with schedules for implementation and other means and techniques necessary and appropriate for demonstrating attainment as expeditiously as practicable but no later than the outermost attainment date for the area's classification; and (4) a RACM analysis to determine whether any additional RACM measures could advance attainment by one year.^[73] In this section, we address the first two components of the attainment demonstration—the technical analyses and control strategy. We addressed the latter two components in section II.D of this document.

The EPA's recommended procedures for modeling ozone as part of an attainment demonstration are contained in “Modeling Guidance for Demonstrating Air Quality Goals for Ozone, PM_2.5 , and Regional Haze” (“Modeling Guidance”).^[74] The Modeling Guidance includes recommendations for a modeling protocol, model input preparation, model performance evaluation, use of model output for the numerical NAAQS attainment test, and modeling documentation. Air quality modeling is performed using meteorology and emissions from a base year, and the predicted concentrations from this base case modeling are compared to air quality monitoring data from that year to evaluate model performance.

Once the model performance is determined to be acceptable, future year emissions are simulated with the model. The relative (or percent, %) change in modeled concentration due to future emissions reductions provides a relative response factor (RRF). Each monitoring site's RRF is applied to its monitored base year design value to provide the future design value for comparison to the NAAQS. The Modeling Guidance also recommends supplemental air quality analyses, which may be used as part of a weight of evidence analysis. A weight of evidence analysis corroborates the attainment demonstration by considering evidence other than the main air quality modeling attainment test, such as trends and additional monitoring and modeling analyses. Lastly, an unmonitored area analysis is used to predict areas of high ozone concentrations where air quality monitoring data are not available. This analysis utilizes interpolated ambient data with modeled outputs to determine gradient-adjusted spatial fields. Section 4.7 of the Modeling Guidance provides guidelines for estimating design values at unmonitored grid cells.

The Modeling Guidance does not require a particular year to be used as the base year for 8-hour ozone plans.^[75] The Modeling Guidance states that the most recent year of the National Emissions Inventory ^[76] may be appropriate for use as the base year for modeling, but that other years may be more appropriate when considering meteorology, transport patterns, exceptional events, or other factors that may vary from year to year.^[77] Therefore, the base year used for the attainment demonstration need not be the same year used to meet the requirements for emissions inventories and RFP.

With respect to the list of adopted measures, CAA section 172(c)(6) requires that nonattainment area plans include enforceable emission limitations and such other control measures, means, or techniques (including economic incentives such as fees, marketable permits, and auctions of emission rights), as well as schedules and timetables for compliance, as may ( printed page 69922) be necessary or appropriate to provide for timely attainment of the NAAQS.^[78] Under the 2015 Ozone SRR, all control measures needed for attainment must be implemented no later than the beginning of the attainment year ozone season.^[79] The attainment year ozone season is defined as the ozone season immediately preceding a nonattainment area's maximum attainment date.^[80]

In addition, with respect to ozone nonattainment areas that are classified Extreme, CAA section 182(e)(5) allows the Agency to exercise discretion in approving Extreme area attainment plans that rely, in part, on provisions that anticipate the development of new control techniques or improvement of existing control technologies (referred to herein as “new technology” provisions) and an attainment demonstration based on such provisions. The State must demonstrate that such provisions are not necessary to achieve the incremental emission reductions required during the first 10 years after designation as nonattainment ( i.e., emission reductions required through August 3, 2028, as applied to the 2015 ozone NAAQS). Given that controls must be in place throughout the applicable ozone season, and given that the ROP and RFP demonstration requirements call for emissions milestones every three years, in practical terms as applied to the 2015 ozone NAAQS, this means that the new technology provisions can be used, in part, to address emission reduction requirements in the attainment year (2037) and RFP milestone years in the second 10 years of the 20-year attainment period (2029, 2032, and 2035).

CAA section 182(e)(5) also requires the State to submit enforceable commitments with the attainment plan to develop and adopt contingency measures to be implemented if the new technology provisions fall short of the necessary reductions. Such contingency measures must be submitted to the EPA as SIP revisions no later than three years before the proposed implementation of the new technology provisions and must be adequate to achieve sufficient emission reductions, alongside other approved plan provisions, to achieve the applicable periodic emission reductions. As applied to the 2015 ozone NAAQS, the State would identify any anticipated shortfall in emission reductions and submit contingency measures to cover that shortfall by January 1, 2034, ( i.e., three years prior to the 2037 attainment year) or three years prior to any RFP milestone year emissions level ( e.g., by January 1, 2032, for the 2035 RFP milestone year).

2. Summary of the State's Submission

a. Photochemical Modeling

The SJV 2022 Ozone Plan includes photochemical modeling for the 2015 ozone NAAQS performed by CARB. The modeling relies on a 2018 base year and demonstrates attainment of the 2015 ozone NAAQS in 2037.

As a general matter, the modeling for the SJV 2022 Ozone Plan represents the most up-to-date photochemical modeling performed for the area, accounting for improved chemical gaseous and particulate mechanisms, improved computational resources and post-processing utilities, enhanced spatial and temporal allocations of the emissions inventory, and CARB's latest attainment demonstration methodology at the time of plan development. Air quality modeling included in the SJV 2022 Ozone Plan is described briefly in Chapter 5 and in detail in Appendix F (“Modeling Attainment Demonstration and Modeling Protocol”). The plan discusses its modeling emissions inventory in Attachment G (“Modeling Emissions Inventory”) and supplements the plan's modeling results with a weight of evidence analysis in Appendix H (“Weight of Evidence”).

Appendix F of the SJV 2022 Ozone Plan provides a description of model input preparation procedures, various model configuration options, and model performance statistics. The modeling protocol for the SJV 2022 Ozone Plan contains all the elements recommended in the Modeling Guidance, including: selection of model, time period to model, modeling domain, and model boundary conditions and initialization procedures; a discussion of emissions inventory development and other model input preparation procedures; model performance evaluation procedures; selection of days; and other details for calculating RRFs. Appendix F also provides the coordinates of the modeling domain.

Appendix G of the SJV 2022 Ozone Plan thoroughly describes the development of the modeling emissions inventory, including its chemical speciation, its spatial and temporal allocation, its temperature dependence, and quality assurance procedures.

The 2023 CARB Staff Report for the SJV 2022 Ozone Plan provides additional information about CAA requirements that apply to the San Joaquin Valley, including information on the attainment demonstration, CARB's aggregate emission reduction commitments with an associated schedule of control measures to be presented to the Board, and control measure commitments by the District.^[81 82] The 2026 Extreme Ozone SIP Revision revises the State's control strategy to attain the 2015 ozone NAAQS, with corresponding revisions to the SJV 2022 Ozone Plan aggregate emission reduction commitments. We describe these changes in section II.E.2.b of this document. While CARB has revised its schedule of control measures and added CAA section 182(e)(5) new technology provisions into its attainment plan, it intends to achieve the same total emission reductions accounted for in the modeled attainment demonstration of SJV 2022 Ozone Plan.^[83]

The modeling analysis uses version 5.2.1 of the CMAQ photochemical model, developed by the EPA. To prepare meteorological input for CMAQ, the Weather Research and Forecasting (WRF) model version 4.2.1 from the National Center for Atmospheric Research was used. CMAQ and WRF are both recognized in the Modeling Guidance as technically sound, state-of-the-art models. The areal extent and the horizontal and vertical resolution used in these models are adequate for modeling ozone in the San Joaquin Valley.

The WRF meteorological model results and performance statistics are described in sections 3.1 (“Meteorological Model Evaluation”) of Appendix F of the SJV 2022 Ozone Plan. The District and CARB evaluated the performance of the WRF model through a series of simulations and concluded that the daily WRF simulation for 2018 performed comparably to recent WRF modeling studies of ozone formation in California. The District's conclusions are supported by hourly time series for each of the San Joaquin Valley subregions (northern, central, and southern), with performance statistics provided in Table 8 of Appendix F for ( printed page 69923) wind speed, temperature and relative humidity.

Ozone model performance and related statistics are described in the SJV 2022 Ozone Plan, Appendix F, section F.3.3 (“Air Quality Model Evaluation”), which includes tables of statistics recommended in the Modeling Guidance for ozone in the San Joaquin Valley. Model performance metrics provided in the plan include mean bias, mean error, mean fractional bias, mean fractional error, normalized mean bias, normalized mean error, root mean square error, and correlation coefficient. In addition, plots were provided in evaluating the modeling: time-series plots comparing the predictions and observations, scatter plots for comparing modeled and observed ozone concentrations, and box plots summarizing model performance statistics across different averaging times, as well as frequency distributions.

After the State accepted the model performance for the 2018 base case, the model was applied to develop RRFs for the attainment demonstration.^[84] This entailed running the model with the same meteorological inputs as before, but with adjusted emissions inventories to reflect the expected changes between 2018 and the attainment year of 2037. The base year, or “reference year” as referred to by the District and CARB, modeling inventory was the same as the inventory for the modeling base case, except for the exclusion of some emissions events that are random or cannot be projected to the future.^[85] The 2037 inventory projects the base year into the future by including the effect of economic growth and emissions control measures. To develop the RRFs for the 8-hour ozone NAAQS, only the top 10 modeled days were used, consistent with the Modeling Guidance.^[86]

The Modeling Guidance addresses attainment demonstrations with ozone NAAQS based on 8-hour averages, and for the 2015 ozone NAAQS, the SJV 2022 Ozone Plan carried out the attainment test procedure consistent with the Modeling Guidance. The RRFs were calculated as the ratio of future to base year concentrations. The resulting RRFs were then applied to the reference design values at each monitoring site in the San Joaquin Valley to obtain future year 2037 design values, which are summarized in Table 15 of Appendix F of the plan. The modeled 2037 ozone design value at the Clovis monitoring site (the highest ozone concentration site in the nonattainment area) is 0.068 ppm, demonstrating attainment of the 2015 ozone NAAQS.

The SJV 2022 Ozone Plan modeling demonstration includes a weight of evidence demonstration.^[87] The weight of evidence demonstration in Attachment H of the plan includes ambient ozone data and trends, meteorological influences, and precursor emissions trends and reductions to complement the regional photochemical modeling analyses. The 2023 CARB Staff Report for the SJV 2022 Ozone Plan concludes that the weight of evidence analysis supports the conclusions of the photochemical modeling.^[88]

b. Control Strategy

In 2022 through 2023, the State adopted its original control strategy for demonstrating attainment of the 2015 ozone NAAQS in the San Joaquin Valley by 2037 and, in response to intervening events, revised its control strategy in 2026. The revised control strategy includes baseline control measures and aggregate emissions reduction commitments to be fulfilled through CAA section 182(e)(5) new technology provisions, as well as certain control measure commitments.^[89] In the following paragraphs, we summarize the State's original control strategy from the SJV 2022 Ozone Plan and California's 2022 State SIP Strategy, the subsequent events that affected the original control strategy, and the State's revised control strategy from the 2026 Extreme Ozone SIP Revision and related submission materials.

The baseline control measures relied upon in the SJV 2022 Ozone Plan represent rules and regulations adopted through the end of 2021. See Table 2 of this document for the list of District rules relied upon as baseline measures in the SJV 2022 Ozone Plan. CARB's baseline measures include certain area source regulations, including the 2021-2022 amendments to the Consumer Products Regulations and Method 310,^[90] certain on-road mobile source regulations, including the ACT Regulation, Heavy-Duty Warranty Phase 1, Zero-Emission Airport Shuttle Regulation, Omnibus Low NO_X Program, and HD I/M Regulation, and certain off-road mobile source regulations, including the 2016 and 2021 amendments to the Small Off-Road Engine Regulations (“SORE Amendments”).

With respect to control measure commitments, through adoption of the SJV 2022 Ozone Plan, the District committed to explore and implement a variety of stationary source emission reduction opportunities to reduce VOC emissions from equipment and pipeline leaks in the oil and gas sector through enhancements to Leak Detection and Repair (LDAR) requirements or, in the case of sumps, through expansion of applicability.^[91] Specifically, the District committed to explore and implement more stringent LDAR requirements or to reconsider exemptions for sumps for sources regulated under the following District rules:

• Rule 4401 (“Steam-Enhanced Crude Oil Production Well Vents”);
• Rule 4402 (“Crude Oil Production Sumps”);
• Rule 4409 (“Components at Light Crude Oil Production Facilities, Natural Gas Production Facilities, and Natural Gas Processing Facilities”);
• Rule 4455 (“Components at Petroleum Refineries, Gas Liquids Processing Facilities, and Chemical Plants”); ( printed page 69924)
• Rule 4623 (“Storage of Organic Liquids”); and
• Rule 4624 (“Transfer of Organic Liquids”).

The District adopted these commitments as “SIP-strengthening measures” and did not include emissions reductions from them in the attainment demonstration.

For mobile and other sources under CARB's primary jurisdiction, CARB developed and adopted the 2022 State SIP Strategy as a statewide planning document to identify strategies and controls necessary to attain the 2015 ozone NAAQS for multiple nonattainment areas.^[92] CARB committed to pursue new SIP control measures or otherwise address each measure identified in the 2022 State SIP Strategy and directed staff to calculate and commit to emission reductions appropriate to each 2015 ozone NAAQS nonattainment area as the State developed attainment plans for such areas.^[93]

CARB's commitments for the applicable nonattainment areas consisted of two components: (1) a commitment to bring an item to the Board for defined new measures or take other specified actions within CARB's authority by specified dates; and (2) a commitment to achieve aggregate emissions reductions by specified dates.^[94] While the 2022 State SIP Strategy included estimates of the emissions reductions from each of the individual new measures, CARB's overall commitment was to achieve the enforceable emissions reductions necessary from state-regulated sources to attain the NAAQS. Therefore, if a particular measure were to not achieve its expected emissions reductions, the State's overall commitment to achieve the enforceable emissions reductions would still apply.

For the SJV 2022 Ozone Plan, CARB committed to achieve certain aggregate emissions reductions of NO_X and VOC by 2037 in the San Joaquin Valley through 18 control measure commitments from the 2022 State SIP Strategy and three control measure commitments from the previous 2016 State SIP Strategy ^[95] that had not already been fulfilled.^[96] Among the new control measure commitments from the 2022 State SIP Strategy were CARB's Advanced Clean Fleets (ACF) and In-Use Locomotive measures. The Advanced Clean Cars II measure was one of the three control measure commitments from the previous 2016 State SIP Strategy that were relied upon for the attainment demonstration in the SJV 2022 Ozone Plan.

Following the submission of the SJV 2022 Ozone Plan to the EPA, a number of intervening events occurred that affect the control strategy for the San Joaquin Valley for the 2015 ozone NAAQS. Two of these events relate to baseline measures:

• Congress' enactment of statutes disapproving the waivers previously issued by the EPA under CAA section 209(b) for certain on-road regulations, including the ACT Regulation, Heavy-Duty Warranty Phase 1, Zero-Emission Airport Shuttle Regulation, and Omnibus Low NO_X Program; ^[97] and
• Partial disapproval by the EPA of the HD I/M Regulation with respect to vehicles registered out-of-state.^[98]

Three of these events relate to CARB's control measure commitments:

• Congress' enactment of a statute disapproving the waiver issued by the EPA under CAA section 209(b) for the Advanced Clean Cars II Regulation; ^[99]
• Repeal by CARB of the In-Use Locomotive Regulation; ^[100] and
• Partial repeal by CARB of the ACF Regulation.^[101]

Without these Congressionally disapproved CAA section 209(b) waivers, CARB cannot “adopt or attempt to enforce” the corresponding on-road mobile source regulations.^[102] Thus, Congress' disapproval of the waivers means that the corresponding California regulations are no longer enforceable, and the attributed emissions reductions cannot be credited in the baseline emissions projections or, in the case of the Advanced Clean Cars II Regulation, towards meeting CARB's aggregate emission reductions commitments. The partial disapproval by the EPA of the HD I/M Regulation means that the emission reductions attributed to the disapproved portion of the regulation are no longer federally enforceable and thus are not creditable as part of the baseline emissions projections. CARB's repeal of the In-Use Locomotive Regulation and partial repeal of the ACF Regulation, which also never received a waiver of preemption in its original form, affect the State's control strategy commitments because they can no longer be relied upon to contribute emissions reductions towards CARB's aggregate emission reduction commitments for the San Joaquin Valley.

In light of these events, CARB developed, adopted, and submitted the 2026 Extreme Ozone SIP Revision to revise the baseline emissions projections and control strategies for the ozone nonattainment areas classified as Extreme for the 2015 ozone NAAQS, including the San Joaquin Valley. For the San Joaquin Valley, CARB revised the baseline emissions projections to account for Congress' disapprovals of the previously issued waivers for the ACT Regulation, Heavy-Duty Warranty Phase 1, Zero-Emission Airport Shuttle Regulation, and Omnibus Low NO_X Program and the EPA's partial disapproval of the HD I/M Regulation. CARB made this revision by removing the future year emissions reductions attributed to the ACT Regulation, Heavy-Duty Warranty Phase 1, Zero-Emission Airport Shuttle Regulation,^[103] and Omnibus Low NO_X Program, as well as the HD I/M Regulation with respect to vehicles registered out-of-state.

With respect to the State's control strategy commitments, CARB revised or eliminated certain defined measures and revised the aggregate emission reduction commitment for the attainment year (2037) in two steps. In the first step (as adopted in the 2026 Extreme Ozone SIP Revision), CARB ( printed page 69925) narrowed the scope of the ACF Regulation to apply only to State and local government fleets and eliminated the Advanced Clean Cars II, and In-Use Locomotive control measure commitments. In addition, CARB revised the descriptions of certain other defined measures, including those related to on-road heavy-duty trucks, commercial harbor craft, off-road vehicles and equipment, and space and water heaters.

Taking into account the modeled attainment emissions inventory and revisions to the baseline emissions projections and defined control measure commitments, CARB revised its prior emission reductions commitment that had been adopted for the SJV 2022 Ozone Plan. The revised commitment is to achieve aggregate emissions reductions of 36.9 tpd of NO_X and 4.7 tpd of VOC in the San Joaquin Valley by 2037, including a subset for which CARB requests approval under CAA section 182(e)(5) of 24.3 tpd of NO_X and 1.8 tpd of VOC, based on measures identified in the 2026 Extreme Ozone SIP Revision or the 2022 State SIP Strategy.^[104]

In the second step, in adopting the 2026 Extreme Ozone SIP Revision, CARB directed the CARB Executive Officer to work with the EPA and take appropriate action to resolve any approvability issues that may arise regarding the submissions, including the action to revise the commitments that rely on CAA section 182(e)(5), and to address any deficit in the reductions needed to demonstrate attainment, RFP, or other SIP elements.^[105] As duly authorized, CARB's Executive Officer eliminated further control measure commitments for the San Joaquin Valley (such as those for the remaining portion of the ACF Regulation and Commercial Harbor Craft Amendments control measure commitments) and revised the subset of the aggregate emission reduction commitment for the San Joaquin Valley for which CARB requests approval under CAA section 182(e)(5) to 31.2 tpd of NO_X and 4.0 tpd of VOC.^[106] In support of the commitments to the extent they rely on CAA section 182(e)(5), CARB committed to submit contingency measures to the EPA, no later than three years before proposed implementation of the CAA section 182(e)(5) plan provisions, to be implemented if the anticipated technologies do not achieve planned reductions.^[107]

Lastly, in adopting the 2026 Extreme Ozone SIP Revision, CARB included a mechanism in Resolution 26-5 to increase its aggregate emission reduction commitment if the EPA does not approve or act upon any CARB regulation currently pending before the EPA for approval into the California SIP, including as needed to meet requirements for RFP, emissions inventories, or other plan elements, prior to taking action on the 2026 Extreme Ozone SIP Revision.^[108] The SORE Amendments are one such CARB regulation for which the EPA will not take final action prior to final action on the 2026 Extreme Ozone SIP Revision as it pertains to the San Joaquin Valley, and whose emission reductions are not federally enforceable (absent approval into the California SIP) and therefore not creditable as part of the future baseline emissions inventories.

CARB retained emissions reductions attributed to the SORE Amendments in the baseline emissions projections of the 2026 Extreme Ozone SIP Revision. CARB estimates that the emission reductions attributable to the SORE Amendments are approximately 1.24 tpd of NO_X and 8.93 tpd of VOC in the San Joaquin Valley in 2037.^[109] Realigning the emissions reductions attributable to the SORE Amendments from the baseline projection to the aggregate emission reduction commitment, as allowed under CARB Resolution 26-5, CARB's aggregate emission reduction commitment for the San Joaquin Valley would increase to 38.1 tpd of NO_X and 13.6 tpd of VOC in the San Joaquin Valley in 2037, including a subset for which CARB requests approval under CAA section 182(e)(5) of 32.4 tpd of NO_X and 12.9 tpd of VOC, based on measures identified in the 2026 Extreme Ozone SIP Revision or the 2022 State SIP Strategy.

c. Attainment Demonstration

Table 3 of this document summarizes the State's attainment demonstration for the 2015 ozone NAAQS by 2037 in the San Joaquin Valley. For completeness, we include the 2017 base year emissions (which are required for base year emissions purposes, as described in section II.C of this document, and for RFP purposes, as described in section II.F of this document) and the 2018 base year emissions inventory (which the State used for attainment demonstration modeling, as described in section II.E.2.a of this document). Based on the modeled emissions reductions (from 2018 through 2037) necessary to demonstrate attainment, we then present the components of the State's control strategy that would achieve such reductions to demonstrate attainment.

Overall, the State's baseline control strategy, as revised by the 2026 Extreme Ozone SIP Revision and CARB Executive Order S-26-006 and accounting for the emissions reductions attributable to the SORE Amendments as part of CARB's commitments, is projected based on information submitted by the State to achieve 76 percent of the NO_X reductions (121.7 tpd/159.8 tpd) and 63 percent of the VOC reductions (23.5 tpd/37.1 tpd) necessary to attain. The State commits to achieve aggregate emission reductions for the remaining 24 percent of the NO_X reductions and 37 percent of the VOC reductions necessary to attain.

( printed page 69926)

3. The EPA's Review of the State's Submission

a. Photochemical Modeling

As discussed in section II.C of this document, we propose to approve the base year emissions inventory and to find—with certain exceptions discussed herein—that the baseline future year emissions inventories in the SJV 2022 Ozone Plan, as revised by the 2026 Extreme Ozone SIP Revision, reflect appropriate calculation methods and that the latest planning assumptions are properly supported by SIP-approved stationary and mobile source control measures. As such, we propose to find that the use of the baseline future year emissions inventories for modeling purposes is appropriate. In the following paragraphs, we address our findings for the modeling submitted with the SJV 2022 Ozone Plan.

Based on our review of Appendix F of the SJV 2022 Ozone Plan, the EPA finds that the photochemical modeling is adequate for purposes of supporting the attainment demonstration. We present greater detail of our review of the plan's modeling and attainment demonstration in the EPA's “Technical Support Document, EPA Review of Attainment Modeling in the San Joaquin Valley 2022 Ozone Plan for the 2015 Ozone NAAQS,” October 2026 (“EPA's Modeling TSD”). First, we note the extensive discussion of modeling procedures, tests, and performance analyses in the Methodology section of Attachment F and the good model performance. Second, we find the WRF meteorological model results and performance statistics, including hourly time series graphs of wind speed, direction, and temperature for the San Joaquin Valley to be satisfactory and consistent with our Modeling Guidance.^[110] Performance for wind speed, temperature, and relative humidity was evaluated from April to October 2018.^[111] Geographically, model performance is evaluated across the northern, central, and southern San Joaquin Valley subregions. Accurate meteorological predictions in this region are important in simulating chemical transport in the San Joaquin Valley air basin. Overall, the WRF simulation provided reasonable meteorological fields comparable to other WRF modeling studies and is sufficient for the attainment demonstration.

The model performance statistics for ozone are described in Appendix F, section F.3.3 and are based on the statistical evaluation recommended in the Modeling Guidance. Model performance for 8-hour daily maximum ozone in the San Joaquin Valley was evaluated separately for the northern, central, and southern San Joaquin Valley subregions. A geographical and temporal bias is shown in the time series, which sufficiently captures the variability in the maximum daily eight-hour average ozone concentration, with a slight negative bias across the San Joaquin Valley, exhibiting some spatial variability among subregions, including ( printed page 69927) smaller biases in the northern San Joaquin Valley and larger biases in the central and southern San Joaquin Valley in the monitor-based evaluations.

The SJV 2022 Ozone Plan presents scatter plots of monitored and modeled ozone concentrations that also suggest generally good correspondence between modeled and observed concentrations across all San Joaquin Valley subregions. This correspondence reflects the model's capability of reliably predicting the overall magnitude and variability of ozone concentrations, including the higher concentrations that contribute to the top ten days that form the basis for the RRF calculation. While some scatter and bias are present, including a tendency to overpredict at higher concentrations in certain subregions, this does not mean that future concentrations will be overestimated. In addition, the weight of evidence analysis presented in Attachment H of the SJV 2022 Ozone Plan provides additional information with respect to the sensitivity to emissions changes and further supports the model performance. We propose to find the air quality modeling adequate to support the attainment demonstration for the 2015 ozone NAAQS, based on reasonable meteorological and ozone modeling performance, and as supported by the weight of evidence analysis. For additional information regarding the EPA's analysis, please see the EPA's Modeling TSD for this proposed action.

b. Control Strategy

As part of our attainment demonstration review, we must evaluate whether the emission reductions provided by the plan and associated control measures are creditable and sufficient to provide for attainment. We have reviewed the State's submissions for demonstrating attainment of the 2015 ozone NAAQS in the San Joaquin Valley, including the SJV 2022 Ozone Plan and the 2022 State SIP Strategy, which provide the foundations for the State's attainment demonstration for the 2015 ozone NAAQS in the San Joaquin Valley ( e.g., baseline control strategy and emissions inventory, photochemical modeling, and the need for further NO_X and VOC emission reductions), and the 2026 Extreme Ozone SIP Revision and related submission materials, which respond to intervening events and substantially revise the State's control strategy.

We first present our evaluation of the State's baseline control strategy, including CARB's revisions to its mobile source control strategy and consideration of baseline District rule SIP submissions that are pending EPA action. We then present our evaluation of the State's aggregate emission reduction commitments, including CAA section 182(e)(5) new technology provisions and remaining control measure commitments.

i. Baseline Control Strategy

As described in section II.E.2.c of this document, the State's baseline control strategy would achieve a majority of the NO_X and VOC emission reductions necessary to attain the 2015 ozone NAAQS in the San Joaquin Valley. Further, as noted in section II.D.3 of this document, the control measures within the State's baseline control strategy have—with certain exceptions discussed in the following paragraphs—been approved into the California SIP.

First, as shown in Table 2 of this document, we have approved most of the District's control measures relied upon as baseline measures. The exceptions relate to recent amendments to five District rules. In Table 4, we list these rules, the dates on which the rules were amended and submitted for approval as part of the California SIP, and the emissions reductions attributable to each that are not currently SIP-creditable. We further discuss our evaluation of these rules in the EPA's District Rules and Motor Vehicle Emissions Budgets TSD.

The EPA intends to take action on the amended District rules listed in Table 4 but does not anticipate doing so prior to final action on the SJV 70 ppb Ozone SIP. To be credited in baseline emissions projections, the amended rules must be approved as part of the SIP and thereby made federally enforceable. Because the five amended rules listed in Table 4 will likely not be approved by the time the EPA takes final action on the SJV 70 ppb Ozone SIP, we have removed approximately 3.1 tpd NO_X and 0.3 tpd VOC emission reductions that are collectively attributable to them from the baseline control strategy for the attainment demonstration.

Second, as discussed in section II.C.3 of this document, we propose to find that the revised baseline emission projections in the 2026 Extreme Ozone SIP Revision appropriately reflect Congress's enactment of statutes disapproving the waivers previously ( printed page 69928) issued by the EPA for the ACT Regulation, Heavy-Duty Warranty Phase 1, Zero-Emission Airport Shuttle Regulation, and Omnibus Low NO_X Program and the EPA's partial disapproval of CARB's HD I/M Regulation. However, we note that the baseline emission projections reflect reductions from two additional CARB control measures that have not been approved as part of the California SIP.

The 2021 through 2022 Amendments to the Consumer Products Regulations and Method 310 are one of the control measures not yet approved as part of the California SIP, but we are proposing to approve the amendments, as described in section III of this document. If we finalize approval of the amendments as proposed, then they will become federally enforceable and creditable as part of the baseline emissions projections for the attainment demonstration.

For the other control measure not yet approved into the California SIP—the SORE Amendments—CARB included a mechanism through Resolution 26-5 to increase its aggregate emission reduction commitments if the EPA does not approve or act upon on any CARB regulation currently pending before the EPA for approval into the California SIP prior to taking action on the 2026 Extreme Ozone SIP Revision.^[112] Through this mechanism, we have added the emissions reductions attributable to the SORE Amendments to CARB's aggregate emissions reduction commitments—specifically the portion of those commitments for which CARB requests approval under CAA section 182(e)(5). By re-aligning the emissions reductions attributable to the SORE Amendments from the baseline control strategy to the control strategy commitments, we propose to find that CARB has adequately accounted for the reductions necessary to demonstrate attainment. In other words, the emissions reductions previously attributed by the State to the SORE Amendments are no longer considered to be in the baseline control strategy, but to cover the associated shortfall in reductions needed to demonstrate attainment, CARB has provided a mechanism that increases its emission reduction commitments in the event that the SORE Amendments are not approved into the SIP by the time the EPA takes action on the SJV 70 ppb Ozone SIP. In this way, the SJV 70 ppb Ozone SIP adequately accounts for reductions necessary to demonstrate attainment whether or not the SORE Amendments are approved into the SIP prior to the EPA's action on the SIP submission.

ii. Control Strategy Commitments

Through adoption of the SJV 2022 Ozone Plan, the District committed to evaluate and implement LDAR enhancements or to broaden applicability for sources regulated under six District rules. The subject rules, Rules 4401, 4402, 4409, 4455, 4623, and 4624, apply to certain sources in the oil and gas sector. To date, the District has amended all six rules, and CARB has submitted all six rules for approval as part of the California SIP. The EPA has approved three of the amended rules (Rules 4401, 4409, and 4623) into the California SIP.^[113]

The District adopted the amended rules as SIP-strengthening measures and did not include the associated emissions reductions in the attainment demonstration. Collectively, the District estimates that the three approved amended rules would reduce VOC emissions by approximately 0.89 tpd.^[114] Because the emissions reductions from the amended District Rules 4401, 4409, and 4623 are not included in baseline emissions projections or relied upon for RFP or attainment demonstration purposes, they are available to offset shortfalls in the baseline control strategy. The District estimates that the three amended District rules that have not yet been approved would further reduce VOC emissions by approximately 0.2 tpd.^[115]

The attainment demonstration of the SJV 70 ppb Ozone SIP relies on enforceable commitments by CARB to attain the 2015 ozone NAAQS in the San Joaquin Valley in 2037. As shown in Table 3 of this document, the SJV 70 ppb Ozone SIP relies on adopted measures to achieve the majority of the emissions reductions needed to attain the 2015 Ozone NAAQS by 2037. The balance of the reductions needed for attainment is in the form of enforceable commitments to take certain specific regulatory and nonregulatory actions within prescribed periods and to achieve aggregate emission reductions of NO_X and VOC in the San Joaquin Valley in 2037. The enforceable commitments made by CARB through adoption of the SJV 70 ppb Ozone SIP are similar to the enforceable commitments that the EPA has approved as part of attainment demonstrations in previous California air quality plans.^[116]

The EPA has previously accepted enforceable commitments in lieu of adopted control measures in attainment demonstrations when the circumstances warrant them and when the commitments meet specific criteria. We believe that, with respect to the 2015 ozone NAAQS in the San Joaquin Valley, circumstances warrant the consideration of enforceable commitments as part of the attainment demonstration. First, as shown in Table 3 of this document, a substantial portion of the emission reductions needed to demonstrate attainment in the San Joaquin Valley come from measures adopted prior to adoption and submittal of the SJV 2022 Ozone Plan. As a result of these State and District efforts, most emissions sources in the San Joaquin Valley are currently subject to stringent emission limitations and other requirements, leaving fewer and more technologically challenging opportunities to further reduce emissions. In the 2022 State SIP Strategy, CARB identified potential control measures that could provide many of the additional emissions reductions needed for attainment. However, the timeline needed to develop, adopt, and implement these measures went beyond the required submittal date for the attainment demonstration for the San Joaquin Valley for the 2015 ozone NAAQS. These circumstances warrant CARB's reliance on enforceable commitments as part of the attainment demonstration for the 2015 ozone NAAQS.

Given the State's demonstrated need for reliance on enforceable commitments, we consider the three factors the EPA uses to determine whether the use of enforceable commitments in lieu of adopted measures to meet CAA planning requirements is approvable: (a) Does the commitment address a limited portion of the statutorily-required program; (b) is the State capable of fulfilling its ( printed page 69929) commitment; and (c) is the commitment for a reasonable and appropriate period of time.

For the first factor, we look to see if the commitment addresses a limited portion of a statutory requirement such as the amount of emissions reductions needed to demonstrate attainment of the NAAQS in a nonattainment area. For this calculation, reductions assigned to the CAA section 182(e)(5) new technologies provisions are not counted as commitments.^[117] Table 3 of this document shows emission reductions needed to demonstrate attainment of the 2015 ozone NAAQS in the San Joaquin Valley and the aggregate emissions reductions commitment by CARB. Based on these values, we have calculated the percent of required reductions that would come from enforceable commitments by CARB (other than new technology measures).

When compared to the total reductions needed to demonstrate attainment (excluding the CAA section 182(e)(5) reductions in the attainment demonstration), the remaining portion of the enforceable commitments represents approximately four percent of the reductions needed for NO_X and two percent of the reductions needed for VOC. Historically, the EPA has approved SIPs with enforceable commitments in the range of approximately 10 percent of the total needed reductions for attainment.^[118] Thus, we find that CARB's enforceable commitments in the SJV 70 ppb Ozone SIP address a limited portion of the required emission reductions.

For the second factor, we consider whether CARB is capable of fulfilling its enforceable commitments. In this instance, the enforceable emission reductions commitment is 5.7 tpd of NO_X and 0.7 tpd of VOC in the San Joaquin Valley in 2037. We propose to approve four of the defined measures that CARB is relying on to meet its commitments. Table 5 of this document lists the four defined measures and CARB estimated emissions reductions for each. We note that the emissions estimates shown in Table 5 are only estimates and are not binding on CARB under the terms of the commitments CARB has made for the 2022 State SIP Strategy, as revised by the 2026 Extreme Ozone SIP Revision. Rather, CARB has committed to take certain regulatory and nonregulatory actions according to the schedule in the 2022 State SIP Strategy or, as applicable, the 2026 Extreme Ozone SIP Revision and to achieve enforceable emission reductions in 2037. The reductions from any one measure in Table 5 could be more or less than the estimates shown.

California DPR has already adopted the regulation anticipated under the defined measure to mitigate health risks associated with the use of the pesticide 1,3-Dichloropropene. CARB estimates that the adopted regulation will provide 0.4 tpd of VOC reductions in the San Joaquin Valley by 2037. We anticipate that the balance of the commitment for VOC reductions would be achieved through CARB's fulfillment of the defined measure for consumer products standards. Based on the estimates in the 2026 Extreme Ozone SIP Revision for the South Coast from future amendments to consumer products regulations and the relative populations of the San Joaquin Valley and the South Coast, we expect that the measure would achieve approximately 2.0 tpd of VOC reductions in the San Joaquin Valley by 2037.^[119]

For NO_X , CARB expects to achieve the emissions reductions through actions taken under their Heavy-Duty Trucks Strategy. The proposed actions that CARB anticipates taking under the Heavy-Duty Trucks Strategy could include actions such as: ^[120]

• Cleaner new engine certification standards similar to the January 2023 Heavy-Duty Final Rule; ^[121]
• Development of new methods for reducing real-world emissions to maintain emissions reductions throughout a vehicle's lifetime;
• Turnover of in-use vehicles to cleaner technologies at the end of their useful life; and ( printed page 69930)
• Establishing regions/zones where cleaner vehicle technologies are used.

We believe that CARB could take appropriate actions under this list but note that CARB's authority for, and the appropriateness of, any particular action would turn on the specific content of the requirements and necessitate case-by-case evaluation. In addition, while we expect these actions to achieve most if not all the emissions reductions anticipated by CARB from this measure, we also note that the enforceable commitment by CARB to achieve emissions reductions anticipates other means to meet or revise the obligation. For instance, if actual emissions decreases occur that exceed the projections reflected in the current emission inventory, CARB could submit an updated emissions inventory to the EPA as part of a SIP revision.^[122] CARB indicates that the SIP revision would outline the changes that have occurred and provide appropriate tracking to demonstrate that aggregate emissions reductions sufficient for attainment are being achieved through enforceable emissions reduction measures.^[123]

In this case, the 2037 NO_X motor vehicle emissions budgets in the 2026 Extreme Ozone SIP Revision for the San Joaquin Valley, for which we are proposing approval herein, are 5.4 tpd lower than the on-road motor vehicle emissions estimates relied upon to develop the attainment demonstration.^[124] If the Heavy-Duty Truck Strategy does not achieve the anticipated 5.7 tpd of NO_X emissions reductions, CARB could revise its commitment through a SIP revision that incorporates the lower on-road emissions estimates reflected in the motor vehicle emissions budgets.

Thus, we believe that CARB is capable of meeting its enforceable commitments to adopt measures that will reduce emissions to the levels needed to attain the 2015 ozone NAAQS in the San Joaquin Valley by 2037.

For the third factor, we consider whether the commitment is for a reasonable and appropriate period of time. To meet the commitments to reduce emissions to the levels needed to attain the 2015 ozone NAAQS in the San Joaquin Valley, CARB has committed to pursue the measures or otherwise address each measure as described in the 2022 State SIP Strategy by the dates specified in Attachment A to CARB Resolution 22-14. With respect to the Consumer Products Standards measure, CARB has committed to bring the measure to the CARB Board by 2027 with implementation beginning in 2028. Under the 2026 Extreme Ozone SIP Revision, CARB has committed to begin bringing measures to the Board under the Heavy-Duty Trucks Strategy in 2028 with implementation beginning in 2030.^[125] As noted previously, the measure related to reduced health risk associated with 1,3-Dichloropropoene pesticides has already been adopted.

We believe that the schedule to bring the measures to the CARB Board is appropriate given the technological and economic challenges associated with the measures and given the procedures under State law for development and adoption of these measures. In addition, these reductions are not needed to meet RFP milestones for the 2015 ozone NAAQS and the adoption timeframe ensures adequate time for implementation by 2037. Thus, the commitments are for a reasonable and appropriate period of time.

For ozone nonattainment areas classified as Extreme, the CAA recognizes that an attainment demonstration may need to rely to a certain extent on new or evolving technologies, given the long time period between developing the initial plan and attaining the standard, and the degree of emissions reductions needed to attain. To address these needs, CAA section 182(e)(5) authorizes the EPA to approve provisions in an Extreme area plan that “anticipate development of new control techniques or improvement of existing control technologies” and to approve an attainment demonstration based on such provisions if the State demonstrates that: “(A) such provisions are not necessary to achieve the incremental emission reductions required during the first 10 years after November 15, 1990; and (B) the State has submitted enforceable commitments to develop and adopt contingency measures to be implemented . . . if the anticipated technologies do not achieve the planned reductions.” The State must submit these contingency measures to the EPA no later than three years before the proposed implementation of these long-term measures and the contingency measures must be “adequate to produce emission reductions sufficient, in conjunction with other approved plan provisions, to achieve the periodic emission reductions required by [CAA sections 182(b)(1) or (c)(2)] and attainment by the applicable dates.”

The General Preamble further provides that the new technology measures contemplated by CAA section 182(e)(5) may include those that anticipate future technological developments as well as those that require complex analyses, decision making, and coordination among a number of government agencies.^[126] An attainment demonstration that relies on long-term new technology measures under CAA section 182(e)(5) must identify any such measures and contain a schedule outlining the steps leading to final development and adoption of the measures.^[127]

CARB has demonstrated a clear need for emissions reductions from new and improved control technologies to reduce air pollution in the San Joaquin Valley. The adopted control measures and enforceable commitments, discussed above, provide the majority, but not all, of the balance of the emissions reductions needed to attain the 2015 ozone NAAQS by 2037. Through adoption of the SJV 70 ppb Ozone SIP, CARB commits to achieve aggregate emissions reductions from a combination of defined and new technology measures of 36.9 tpd of NO_X and 4.7 tpd of VOC in the San Joaquin Valley in 2037, including a subset for which CARB requests approval under the CAA section 182(e)(5) provision of 31.2 tpd of NO_X and 4.0 tpd of VOC.^[128]

As discussed in this document, in adopting the 2026 Extreme Ozone SIP Revision, CARB adopted a provision under which CARB commits to achieve additional emissions reductions associated with CARB regulations that are relied upon to meet requirements for RFP, emissions inventories, or other plan elements and that have been submitted to the EPA but for which the EPA has not taken final action. CARB's SORE Amendments are one set of CARB regulations that fit in that category because they were submitted but remain pending action by the EPA. As such, consistent with CARB Resolution 26-5, we removed the emission reductions from the SORE Amendments from the future baseline emissions inventories and added them to the commitment related to the CAA section 182(e)(5) new technology provisions. In light of this realignment of emission reductions to the new technology provisions, CARB's aggregate emissions reduction commitments from the combination of defined and new technology measures is ( printed page 69931) 38.1 tpd of NO_X and 13.6 tpd of VOC in the San Joaquin Valley in 2037, including a subset for which CARB requests approval under the CAA section 182(e)(5) provision of 32.4 tpd of NO_X and 12.9 tpd of VOC, accounting for the estimated emissions reductions attributable to the SORE Amendments. To be clear, we are not proposing to approve the SORE Amendments into the SIP at this time, but rather to approve the SJV 70 ppb Ozone SIP revision in light of California's enforceable commitments, which adequately account for a future with or without the SORE Amendments being approved into the SIP and detail the future steps that would be taken under both eventualities.

The EPA proposes to find that the SJV 70 ppb Ozone SIP does not rely on the new technology measure reductions until the attainment year (2037) and, thus, does not rely on them to achieve RFP milestones for the first 10 years after designation (for the 2015 ozone NAAQS). Also, we propose to find CARB's description of the new technology measures in the 2022 State SIP Strategy, as revised in the 2026 Extreme Ozone SIP Revision, to be adequate. Lastly, through CARB Resolution 26-5, CARB has committed to submit contingency measures to the EPA no later than three years before proposed implementation of the plan provisions to be implemented if the anticipated technologies do not achieve planned reductions.^[129] In the case of the San Joaquin Valley, because the attainment demonstration relies on emissions reductions from new technology measures in the attainment year, CARB must submit contingency measures to cover any expected shortfall in reductions from those measures by January 1, 2034. We propose to find that CARB's commitment complies with the corresponding criterion in CAA section 182(e)(5).

c. Attainment Demonstration

To tie the EPA's evaluation together, we reiterate our conclusions with respect to the State's photochemical modeling, baseline control strategy, and aggregate emission reduction commitments (including CAA section 182(e)(5) new technology provisions and remaining control measure commitments) and describe additional emission reduction factors and modeling analysis that contribute to our review of the State's attainment demonstration for the 2015 ozone NAAQS in the San Joaquin Valley.

The EPA proposes to find that the SJV 2022 Ozone Plan's photochemical modeling is adequate to support the attainment demonstration for the 2015 ozone NAAQS in the San Joaquin Valley.

We must find that the emissions reductions that are relied on for attainment are creditable and are sufficient to provide for attainment. In section III.E.3.b of this document, we noted that we are proposing to approve four defined control measure commitments and explained how CARB's enforceable emissions reduction commitments were adequately justified and supported either by commitments to bring regulatory or nonregulatory initiatives to the CARB Board on a prescribed scheduled to meet aggregate emissions reduction commitments for 2037 or by commitments to submit contingency measures as necessary to cover any shortfall in emissions reductions anticipated to be achieved through implementation of new technology provisions.

The only reductions that are relied upon by the attainment demonstration that are not already approved as part of the SIP or supported by CARB commitments are the reductions included in the baseline from certain adopted and submitted District rule amendments for which the EPA has not taken final action. These rule amendments listed in Table 3 of this document and the emissions reductions attributable to these amendments are approximately 3.1 tpd of NO_X and 0.3 tpd of VOC in 2037.

With respect to the VOC emissions reductions, we note that District amendments to Rules 4401, 4409, and 4623 are not reflected in the baseline strategy or relied upon specifically for the attainment demonstration, and they have been approved into the SIP and provide more emissions reductions (0.9 tpd) than anticipated from the five District rule amendments for which the EPA has not taken action. Thus, there is no shortfall in the control strategy with respect to VOC emissions reductions.

With respect to the NO_X emissions reductions, the EPA intends to take action on the amended District rules listed in Table 5 but does not anticipate doing so prior to final action on the SJV 70 ppb Ozone SIP. We anticipate that the shortfall in the emissions reductions from the control strategy for NO_X will be wholly or partially eliminated by our action on the rule amendments if we finalize approval as proposed herein.

Moreover, based on our review of the photochemical modeling results, we note that the State's photochemical modeling in the SJV 2022 Ozone Plan projected that the State's control strategy would result in the highest predicted future design value in 2037 of 68.8 ppb at the Clovis monitor.^[130] This level is 1.2 ppb below the 2015 ozone NAAQS level of 70 ppb (or 2.1 ppb below the level of 70.9 ppb, which would be truncated to 70 ppb per the form of the standard). Accordingly, we have analyzed the State's attainment demonstration modeling to assess what additional amount of NO_X could be emitted in 2037 while still demonstrating attainment of the 2015 ozone NAAQS. Based on a sensitivity analysis of ozone design values and NO_X emissions between 2032 and 2037 and applying a scaling factor to translate the modeled emissions inventory into the planning emissions inventory, we estimate that an additional 5.59 tpd NO_X emissions could theoretically still result in a modeled demonstration of 70 ppb in 2037 in the San Joaquin Valley (or an additional 9.78 tpd NO_X emissions for a modeled demonstration of 70.9 ppb). For further discussion of this analysis, see section 3.2.1 of the EPA's Modeling TSD. While we do not rely on this estimate as a precise gauge of how much NO_X emission reductions would be necessary for the San Joaquin Valley to attain the 2015 ozone NAAQS, this estimate provides another piece of evidence that some single-digit increment of additional NO_X emissions would not prevent the demonstration of attainment in 2037.

Given our review of the plan's photochemical modeling, the State's revised control strategy (including CAA section 182(e)(5) new technology provisions and remaining control measure commitments), and the many related components and evaluations presented in this document, the EPA proposes to approve the State's attainment demonstration for the 2015 ozone NAAQS in the San Joaquin Valley, as revised by the 2026 Extreme Ozone SIP Revision and CARB Executive Order S-26-006, as meeting the requirements of CAA sections 172(c)(6), 182(c)(2)(A), and 182(e)(5) and 40 CFR 51.1308.

F. Rate of Progress Plan and Reasonable Further Progress Demonstration

1. Statutory and Regulatory Requirements

Requirements for RFP for ozone nonattainment areas are specified in ( printed page 69932) CAA sections 172(c)(2), 182(b)(1), and 182(c)(2)(B). Under CAA section 171(1), RFP is defined as meaning such annual incremental reductions in emissions of the relevant air pollutant as are required under CAA title I, part D (“Plan Requirements for Nonattainment Areas”) or as may reasonably be required by the EPA for the purpose of ensuring attainment of the applicable NAAQS by the applicable date. CAA section 182(b)(1) specifically requires that ozone nonattainment areas classified as Moderate or above demonstrate a 15 percent reduction in VOC between the years 1990 and 1996. The EPA has typically referred to CAA section 182(b)(1) as the rate of progress (ROP) requirement.

For ozone nonattainment areas classified as Serious or higher, CAA section 182(c)(2)(B) requires VOC reductions of at least three percent of baseline emissions per year, averaged over each consecutive three-year period, beginning six years after the baseline year until the attainment date. Under CAA section 182(c)(2)(C), for nonattainment areas classified as Serious and above, a State may substitute NO_X emissions reductions for VOC emissions reductions if such reductions would result in a reduction in ozone concentrations at least equivalent to that which would result from the amount of VOC emissions reductions otherwise required. Additionally, CAA section 182(c)(2)(B)(ii) allows an amount less than three percent of such baseline emissions each year if a State demonstrates to the EPA that its plan includes all measures that can feasibly be implemented in the area in light of technological achievability.

In the 2015 Ozone SRR, the EPA provides that areas classified Moderate or higher will have met the ROP requirements of CAA section 182(b)(1) if the area has a prior, fully-approved 15 percent ROP plan.^[131] For such areas, the EPA interprets the RFP requirements of CAA section 172(c)(2) to require areas classified as Moderate to provide a 15 percent emissions reduction of ozone precursors within six years of the baseline year. Areas classified as Serious or higher must meet the RFP requirements of CAA section 182(c)(2)(B) by providing an 18 percent reduction of ozone precursors in the first 6-year period and an average ozone precursor emissions reduction of three percent per year for all remaining 3-year periods thereafter.^[132] The 2015 Ozone SRR allows substitution of NO_X reductions for VOC reductions to meet the CAA section 172(c)(2) and 182(c)(2)(B) RFP requirements.^[133]

Except as specifically provided in CAA section 182(b)(1)(C), emissions reductions from all SIP-approved, federally promulgated, or otherwise SIP-creditable measures that occur after the baseline year are creditable for purposes of demonstrating that the RFP targets are met. Because the EPA has determined that the passage of time has caused the effect of certain exclusions to be de minimis, the RFP demonstration is no longer required to calculate and specifically exclude reductions from measures related to motor vehicle exhaust or evaporative emissions promulgated by January 1, 1990; regulations concerning Reid vapor pressure promulgated by November 15, 1990; measures to correct previous RACT requirements; and measures required to correct previous inspection and maintenance (I/M) programs.^[134]

The 2015 Ozone SRR requires the RFP baseline year to be the most recent calendar year for which a complete triennial inventory was required to be submitted to the EPA.^[135] For the purpose of developing RFP demonstrations for the 2015 ozone NAAQS, the applicable triennial inventory year is 2017.^[136] States may use an alternative baseline emissions inventory provided that the year selected corresponds with the year of the effective date of designation as nonattainment for that NAAQS.^[137]

2. Summary of the State's Submission

The SJV 2022 Ozone Plan addresses the 15 percent ROP requirement by noting that the EPA approved a 15 percent ROP plan for the 1-hour ozone NAAQS for the San Joaquin Valley in 1997 and that the 1-hour ozone nonattainment area covers the entire nonattainment area for the 2015 ozone standards.^[138]

To address the RFP requirements, the SJV 2022 Ozone Plan selected 2017 as the RFP baseline year and provided emissions inventories for the RFP baseline, milestone, and attainment years.^[139] The future-year emissions inventory projections generally take into account rules and regulations adopted through the end of 2021. The RFP demonstration in the SJV 2022 Ozone Plan uses NO_X substitution beginning in milestone year 2023 to meet VOC emission targets and concluded that the RFP demonstration meets the applicable requirements for each milestone year and the attainment year.

The baseline emissions projections used for the RFP demonstration in the SJV 2022 Ozone Plan were updated in the 2026 Extreme Ozone SIP Revision. The EPA has evaluated compliance with the RFP demonstration requirement in this document on the basis of the updated RFP demonstration included in the 2026 Extreme Ozone SIP Revision and the documentation provided therein as well as the relevant documentation included in the SJV 2022 Ozone Plan.

To develop the emissions inventories for remaining RFP milestone years (2023, 2026, 2029, 2032, and 2035) and the attainment year (2037), the District and CARB relied upon the same growth and control factors used in the attainment demonstration, as further described in section II.C (regarding emissions inventories) of this document. The 2026 Extreme Ozone SIP Revision revised the on-road motor vehicle portion of the baseline emissions projections included in the SJV 2022 Ozone Plan that were based on EMFAC2017 to account for developments that occurred after plan adoption, including Congress's enactment of statutes disapproving waivers previously issued by the EPA for certain CARB mobile source regulations and the EPA's partial disapproval of CARB's HD I/M regulation as it applies to out-of-state registered vehicles. The 2026 Extreme Ozone SIP Revision did not revise the baseline emissions projections prepared for the SJV 2022 Ozone Plan for the other major source categories, including stationary and area-wide sources and off-road (nonroad) vehicles and equipment.

The RFP demonstration for the San Joaquin Valley for the 2015 ozone NAAQS is shown in Table 6 of this document. The RFP demonstration is based on the RFP baseline emissions inventory and the revised baseline emissions projections for the RFP milestone years and attainment year included in the 2026 Extreme Ozone SIP Revision. CARB adjusted future baseline emissions inventories to accommodate the EMFAC2021-derived motor vehicle emissions budgets included in the 2026 Extreme Ozone SIP Revision and to account for emission reductions credits (ERCs) available under the District's new source review (NSR) permitting program for new and modified stationary sources. ( printed page 69933)

To be conservative in the adjustment regarding the use of the EMFAC2021 model, CARB only includes increases in emissions associated with the EMFAC2021-derived budgets as compared with the motor vehicle emissions estimates prepared for the baseline emissions projections (and based on EMFAC2017 as amended to exclude emissions reductions from regulations for which waivers have been disapproved or for which the EPA has issued a partial disapproval).^[140] CARB did not include emissions decreases associated with the EMFAC2021-derived budgets in the RFP demonstration.

In addition to the EMFAC2021 adjustment, the RFP demonstration takes into account ERCs banked prior to 2017 ( i.e., the RFP baseline year) to the extent that the expected ERC use exceeds the assumed level of growth in emissions by the subject sources that is included in the baseline emissions projections.^[141] Under the EPA's SIP regulations for nonattainment NSR programs, a State may allow new major stationary sources or major modifications to use ERCs that were generated through shutdown or curtailed emissions units occurring before the base year of an attainment plan. However, to use such ERCs, the projected emissions inventory used to develop the attainment demonstration must explicitly include the emissions from such previously shutdown or curtailed emissions units.^[142] The District has elected to provide for use of pre-base year ERCs as offsets by explicitly including such ERCs in the 2037 attainment year inventory.^[143] The ERC set-aside in the attainment year (2037) is 2.43 tpd of NO_X .^[144] The ERC adjustment is only needed for NO_X, not VOC. For the purposes of the RFP demonstration, the 2026 Extreme Ozone SIP Revision accounts for the ERC set-aside in each RFP milestone year as well as the attainment year.

The RFP demonstration calculates future year VOC targets from the 2017 baseline, consistent with CAA section 182(c)(2)(B)(i), which requires reductions of “at least 3 percent of baseline emissions each year,” and it substitutes NO_X reductions for VOC reductions beginning in milestone year 2023 to meet VOC emission targets.^[145] CARB concludes, based on the calculations and explanation provided in the 2026 Extreme Ozone SIP Revision, that the 2026 Extreme Ozone SIP Revision demonstrates RFP for each milestone year as well as for the attainment year in the San Joaquin Valley for the 2015 ozone NAAQS.

3. The EPA's Review of the State's Submission

We have reviewed the SJV 2022 Ozone Plan and agree that the EPA has approved a 15 percent ROP demonstration for the 1-hour ozone NAAQS, fulfilling the requirements of CAA section 182(b)(1) ^[146] for the San Joaquin Valley and that, as a result, there is no need to demonstrate another 15 percent reduction in VOC for this area.

The RFP demonstration in the 2026 Extreme Ozone SIP Revision derives from the same emissions inventories presented in section II.C of this document. In section II.C of this document, we propose to approve the revised 2017 base year emissions inventories for the 2015 ozone NAAQS. With respect to the baseline future year ( printed page 69934) emissions inventories, as further explained in section II.C of this document, we have reviewed the growth and control factors and find them acceptable and conclude that the future baseline emissions inventories in the SJV 2022 Ozone Plan reflect appropriate calculation methods and the latest planning assumptions and appropriately account for the pre-baseline ERCs.

Under the CAA and the EPA's implementing regulations for the 2015 ozone NAAQS, with certain exceptions not relevant here, all emission reductions from SIP-approved or federally promulgated measures that occur after the baseline emissions inventory year are creditable for purposes of the RFP requirements, provided the reductions meet the requirements for creditability, including the need to be enforceable, permanent, quantifiable, and surplus.^[147]

With respect to the RFP demonstration in the 2026 Extreme Ozone SIP Revision, we note that the future baseline emissions inventories take into account emissions reductions from State and local air pollution control rules and regulations adopted by the end of 2021. We have reviewed the District's VOC and NO_X rules that are accounted for in the future baseline emissions inventories and used to demonstrate RFP and have concluded that emissions reductions from stationary source controls accounted for the 2026 Extreme Ozone SIP Revision are supported by rules approved as part of the SIP, with the exception of amendments to District Rules 4306, 4352, 4354, 4702 and 4905.^[148]

With respect to mobile sources, the EPA has taken action to approve most CARB mobile source regulations that are accounted for in the baseline future year emissions inventories into the California SIP but has not taken action on submissions of certain CARB regulations for which emissions reductions are also included in the baseline future year emissions inventories in the 2026 Extreme Ozone SIP Revision. These regulations include the SORE Amendments.

The EPA expects to take action on the submissions of the District rules listed in Table 4 of this document but may not do so by the time the EPA takes final action on the RFP demonstration for the San Joaquin Valley for the 2015 ozone NAAQS. Because of the timing uncertainty for EPA action on the District rules, we have excluded the associated emissions reductions from the baseline future year emissions inventories included in the 2026 Extreme Ozone SIP Revision for the purposes of our evaluation of the RFP demonstration.

With respect to the SORE Amendments, the EPA will not take final action prior to final action on the SJV 70 ppb Ozone SIP; thus, we are taking the same conservative approach by excluding the emissions reductions associated with the SORE Amendments as part of our evaluation of the RFP demonstration. We have accounted for the exclusion of the emissions reductions associated with District Rules 4306, 4352, 4354, 4702, and 4905, and the SORE Amendments by including adjustments to the baseline future year emissions inventories from the 2026 Extreme Ozone SIP Revision. The specific adjustments that we have made to the baseline future year emissions inventories to account for adopted rules and regulations that are not yet approved as part of the California SIP are listed in Table 7.

In addition, we have reviewed the calculations in the 2026 Extreme Ozone SIP Revision used to demonstrate RFP for the San Joaquin Valley and find that CARB used an appropriate calculation method to demonstrate RFP. In Table 8 of this document, we recreate CARB's RFP demonstration (presented in Table 6 of this document), using the adjustments discussed herein for District rules and CARB regulations relied upon by CARB to demonstrate RFP but not yet approved by the EPA. As shown in Table 8, the San Joaquin Valley continues to meet the RFP requirement in all milestone years and the attainment year, notwithstanding the EPA's adjustments, because the creditable emissions reductions provide for an 18 percent reduction of ozone precursors in the first 6-year period and an average ozone precursor emissions reduction of three percent per year for all remaining 3-year periods thereafter. ( printed page 69935)

Under CAA section 182(c)(2)(B), the RFP demonstration for a Serious ozone nonattainment area will demonstrate RFP based solely on the prescribed annual rate of VOC emission reductions. Alternatively, under CAA section 182(c)(2)(C), the demonstration may satisfy the RFP requirement based on a combination of VOC and NO_X reductions if it demonstrates that reductions of VOC and NO_X would result in a reduction in ozone concentrations at least equivalent to that which would result from the amount of VOC emission reductions otherwise required. For the San Joaquin Valley, the RFP demonstration for all the milestone years and the attainment year rely on a combination of VOC reductions and NO_X reductions from the RFP baseline year of 2017.

The RFP demonstration from the 2026 Extreme Ozone SIP Revision relies on substitution of NO_X emissions reductions for otherwise required VOC emissions reductions on a percentage basis. Thus, for example, a 12 percent reduction of NO_X emissions reductions from RFP baseline year NO_X reductions is used to substitute for a shortfall in VOC emissions reductions equal to 12 percent of RFP baseline year VOC emissions. In terms of tons per day, a 12 percent reduction of NO_X emission reductions equals 12 percent of the RFP baseline NO_X emissions, which in this instance is 12 percent of 232.39 tpd, or 27.9 tpd. A shortfall of 12 percent of VOC emissions reductions refers to 12 percent of RFP baseline VOC emissions, or in this case 12 percent of 325.68 tpd, or 39.1 tpd. Thus, under this example, NO_X emissions reductions of 27.9 tpd substitute for a shortfall of VOC emissions reductions of 39.1 tpd, a ratio of approximately 0.7:1.

The ratio of 0.7:1 for substitution of NO_X for VOC is based on the ratio of NO_X emissions in the RFP baseline year to VOC emissions in the RFP baseline year, and thus it applies to all RFP milestone years and the attainment year that rely on NO_X substitution to demonstrate RFP for the San Joaquin Valley for the 2015 ozone NAAQS. Reliance on a 0.7:1 ratio for substitution of NO_X for VOC for RFP purposes assumes that NO_X emissions reductions are roughly 1.4 times ( i.e., the inverse of the 0.7:1 ratio) more effective at reducing ozone concentration than VOC emissions reductions. This substitution of NO_X reductions for VOC reductions is acceptable under CAA section 182(c)(2)(C) so long as the ozone concentration reductions from 2017 to each milestone year and the attainment year in the San Joaquin Valley under the combined VOC/NO_X emissions reduction scenario are at least equivalent to that which would result under the VOC-only reduction scenario. In other words, the substitution is acceptable so long as NO_X emissions reductions are at least 1.4 times more effective at reducing ozone concentrations than VOC emissions reductions.

CARB and the District provided support for substituting NO_X reductions for VOC reductions in the San Joaquin Valley in section 3.6 of Appendix F of the SJV 2022 Ozone Plan.^[149] CARB and the District present a comparison of design value modeling results for two emissions reduction scenarios at each of the ambient ozone monitoring sites in the San Joaquin Valley. Under one scenario, VOC emissions within the San Joaquin Valley were reduced by 60 percent (three percent for each of the 20 years between the RFP baseline year (2017) and the attainment year (2037)) from emissions in the RFP baseline year. The other scenario is similar to the first except that NO_X emissions were ( printed page 69936) reduced by 60 percent rather than VOC emissions.

The analysis provided by CARB and the District shows that, at all the ambient ozone monitoring sites in the San Joaquin Valley, the ratios of the ozone design value change relative to the NO_X emissions change are greater than those of the VOC emissions change. Further, CARB and the District found that, based on the modeling results, at sites with the highest 2018 ozone design values, the rate of change in ozone concentrations relative to NO_X emissions changes is roughly an order of magnitude larger than the corresponding change in ozone concentrations associated with VOC emissions reductions. Based on these results, CARB and the District concluded that, because the ozone improvement from NO_X reductions is greater than that for VOC reductions, the use of NO_X substitution will result in improved ozone air quality.^[150]

We have reviewed the equivalence demonstration provided by CARB and the District in Appendix F of the SJV 2022 Ozone Plan. We find that it adequately demonstrates through the sensitivity analyses that the reductions of VOC and NO_X in the San Joaquin Valley from 2017 through the attainment year would result in a reduction in ozone concentrations at least equivalent to that which would result from the amount of VOC emission reductions otherwise required. The sensitivity analyses support this conclusion by showing that NO_X emissions reductions are greater than 1.4 times more effective (and perhaps as high as 10 times more effective) at reducing ozone concentrations as compared to VOC emissions reductions. As such, we find that the reliance on NO_X substitution for RFP demonstration purposes for the San Joaquin Valley in the 2026 Extreme Ozone SIP Revision to be consistent with the requirements of CAA section 182(c)(2)(C).^[151]

For these reasons, we have preliminarily determined that the 2026 Extreme Ozone SIP Revision demonstrates RFP in each milestone year, as well as in the attainment year, for the San Joaquin Valley consistent with applicable CAA requirements and EPA regulations. We therefore propose to approve the RFP demonstration for the San Joaquin Valley for the 2015 ozone NAAQS under CAA sections 172(c)(2), 182(b)(1), and 182(c)(2)(B); 40 CFR 51.1310(a)(2); and 40 CFR 51.1310(a)(2)(ii).

G. Motor Vehicle Emissions Budgets for Transportation Conformity

1. Statutory and Regulatory Requirements

Transportation conformity is required under CAA section 176(c) to ensure that federally funded or approved highway and transit activities conform to the purpose of the SIP. This requires Federal actions in nonattainment and maintenance areas to conform to the SIP's goals of eliminating or reducing the severity and number of violations of the NAAQS and achieving timely attainment of the standards. Conformity to the SIP's goals means that such actions will not: (1) cause or contribute to violations of a NAAQS; (2) worsen the severity of an existing violation; or (3) delay timely attainment of any NAAQS or any interim milestone.

Actions involving Federal Highway Administration (FHWA) or Federal Transit Administration (FTA) funding or approval are subject to the EPA's transportation conformity rule, codified at 40 CFR part 93, subpart A. Under this rule, metropolitan planning organizations in nonattainment and maintenance areas coordinate with State and local air quality and transportation agencies, the EPA, the FHWA, and the FTA to demonstrate that an area's regional transportation plans and transportation improvement programs conform to the applicable SIP. This demonstration is typically done by showing that estimated emissions from existing and planned highway and transit systems are less than or equal to the motor vehicle emissions budgets (“budgets”) contained in all control strategy SIPs. Budgets are generally established for specific years and specific pollutants or precursors. Ozone plans should identify motor vehicle emissions budgets for on-road emissions of ozone precursors (NO_X and VOC) in the area for each RFP milestone year and, if the plan demonstrates attainment, the attainment year.^[152]

For budgets to be approvable, they must meet, at a minimum, the EPA's adequacy criteria at 40 CFR 93.118(e)(4). To meet these requirements, the budgets must be consistent with the attainment and RFP requirements and reflect all motor vehicle control measures contained in the attainment and RFP demonstrations.^[153]

The EPA's process for determining adequacy of a budget consists of three basic steps: (1) providing public notification of a SIP submission; (2) providing the public the opportunity to comment on the budgets during a public comment period; and (3) making a finding of adequacy or inadequacy.^[154]

2. Summary of the State's Submission

The SJV 2022 Ozone Plan includes sub-regional ( i.e., county-based) budgets for VOC and NO_X for the 2023, 2026, 2029, 2032, and 2035 RFP milestone years and the 2037 attainment year.^[155] The budgets in the SJV 2022 Ozone Plan were developed using the EMFAC2017 emissions model, which was the latest EPA-approved version of the model available at the time of plan development.^[156] Since the SJV 2022 Ozone Plan was adopted, the EPA has approved CARB's latest version of the EMFAC model, EMFAC2021 with the use of the November 21, 2025 and May 6, 2026 off-model adjustment factors.^[157] The EPA approved EMFAC2021 off-model adjustment factors that remove the estimated emissions reductions attributed to California's ACT Regulation, Heavy-Duty Warranty Phase 1, Zero-Emission Airport Shuttle Regulation, and Omnibus Low NO_X Program from EMFAC2021.^[158] The EPA also approved off-model adjustment factors that incorporate emissions reductions from implementation of CARB's HD I/M Regulation, as partially

( printed page 69937)

approved by the EPA with respect to vehicles registered in-state.^[159 160]

In light of the availability of the updated version of EMFAC with the use of the off-model adjustment factors, CARB revised the budgets from the SJV 2022 Ozone Plan and submitted the updated budgets in the 2026 Extreme Ozone SIP Revision. The 2026 Extreme Ozone SIP Revision includes sub-regional ( i.e., county-based) budgets, as well as regional (whole nonattainment area) budgets, for VOC and NO_X for the 2026, 2029, 2032, and 2035 RFP milestone years and the 2037 attainment year in the San Joaquin Valley. In adopting the 2026 Extreme Ozone SIP Revision on July 23, 2026, CARB adopted the regional budgets for the 2015 ozone NAAQS for the San Joaquin Valley.^[161] CARB did not update the 2023 RFP milestone budgets because, given the passage of time, they will not be used for future transportation conformity determinations. The budgets from the 2026 Extreme Ozone SIP Revision for San Joaquin Valley replace the corresponding budgets contained in the SJV 2022 Ozone Plan.

In addition to reflecting the updated EMFAC model (EMFAC2021), the budgets in the 2026 Extreme Ozone SIP Revision were calculated using updated vehicle activity data. In the case of San Joaquin Valley, the budgets reflected updated VMT and speed activity data from the 2025 FSTIP.^[162] All of the budgets represent average summer weekday emissions and are rounded up to the nearest tpd for emissions greater than 20 tpd and to the nearest tenth for emissions lower than 20 tpd. The regional conformity budgets for VOC and NO_X for the nonattainment area are provided in Table 9 of this document.

3. The EPA's Review of the State's Submission

We have evaluated the submitted budgets in the 2026 Extreme Ozone SIP Revision against our adequacy criteria in 40 CFR 93.118(e)(4) as part of our review of the budgets' approvability ( see section II in the EPA's District Rules and Motor Vehicle Emissions Budgets TSD) and will complete the adequacy review concurrent with our final action on the SJV 70 ppb Ozone SIP. The EPA is not required under its transportation conformity rule to find budgets adequate prior to proposing approval of them.^[163]

The 2026 Extreme Ozone SIP Revision revises the RFP demonstration in the SJV 2022 Ozone Plan using the updated budgets, and we evaluated the revised RFP demonstration as discussed in section II.F of this document. The 2026 Extreme Ozone SIP Revision does not revise the attainment demonstration in the SJV 2022 Ozone Plan using the updated budgets. However, CARB provided a technical assessment of the consistency of the updated budgets with the attainment demonstration in the SJV 2022 Ozone Plan.^[164] This assessment shows that the updated budgets, when considered together with all other emission sources, are consistent with applicable requirements for attainment. We further discuss the EPA's review of the revised regional budgets and their consistency with the plan's RFP and attainment demonstrations in section II of the EPA's District Rules and Motor Vehicle Emissions Budgets TSD.

For the reasons discussed in sections II.E and II.F of this document, respectively, we propose to approve the attainment and RFP demonstrations for the San Joaquin Valley for the 2015 ozone NAAQS. The updated motor vehicle emissions budgets for the San Joaquin Valley in the 2026 Extreme Ozone SIP Revision, as presented in Table 9 of this document, are consistent with these demonstrations, are clearly identified and precisely quantified, and meet all other applicable statutory and regulatory requirements, including the adequacy criteria in 40 CFR 93.118(e)(4) and (5). This document initiates the adequacy process for the budgets included in this SIP submission and begins the public comment period. Comments must be submitted by the close of the comment period on the proposed rule. If we finalize our adequacy determination and approval of the budgets for the 2015 ozone NAAQS in the 2026 Extreme Ozone SIP Revision, as proposed, the MPOs in the San Joaquin Valley and the U.S. Department of Transportation would be required to use these budgets for future transportation conformity determinations.

Under our transportation conformity rule, as a general matter, once budgets are approved, they cannot be superseded by revised budgets submitted for the same CAA purpose and the same period of years addressed by the previously approved SIP until the EPA approves the revised budgets as a SIP revision. In other words, as a general matter, such approved budgets cannot be superseded by revised budgets found adequate, but rather only through approval of the revised budgets, unless the EPA specifies otherwise in its approval of a SIP by limiting the duration of the approval to last only until subsequently submitted budgets are found adequate.^[165]

( printed page 69938)

In this instance, CARB has requested that we limit the duration of our approval of the budgets in the 2026 Extreme Ozone SIP Revision only until the effective date of the EPA's adequacy finding for any subsequently submitted budgets.^[166] Generally, we will consider a State's request to limit an approval of motor vehicle emissions budgets only if the request includes the following elements:

• An acknowledgement and explanation as to why the budgets under consideration have become outdated or deficient;
• A commitment to update the budgets as part of a comprehensive SIP update; and
• A request that the EPA limit the duration of its approval to the time when new budgets have been found to be adequate for transportation conformity purposes.^[167]

CARB's request includes an explanation for why the budgets have become, or will become, outdated or deficient. In short, CARB has requested that we limit the duration of the approval of the budgets because CARB expects the next version of EMFAC to estimate higher emissions for certain onroad motor vehicle categories and certain areas of the State, necessitating updates to the budgets once the next version of EMFAC is submitted and approved by the EPA.

If the EPA approves the future EMFAC model, CARB explains that the budgets from the 2026 Extreme Ozone SIP Revision, for which we are proposing approval in this document, may become outdated and will need to be revised. In addition, CARB states that, without the ability to replace the budgets using the budget adequacy process, the benefits of using the updated data may not be realized for a year or more after the updated SIP (with the future budgets) is submitted, due to the length of the SIP approval process. We find that CARB's explanation for limiting the duration of the approval of the budgets is appropriate and provides us with a reasonable basis on which to limit the duration of the approval of the budgets.

We note that CARB has not committed to update the budgets as part of a comprehensive SIP update, but as a practical matter, CARB must submit a SIP revision that includes updated demonstrations as well as the updated budgets to meet the adequacy criteria in 40 CFR 93.118(e)(4); and thus, we do not need a specific commitment for such a plan at this time.^[168] For the reasons provided herein, and in light of CARB's explanation for why the budgets will become outdated and should be replaced upon an adequacy finding for updated budgets, we propose to limit the duration of our approval of the budgets in the 2026 Extreme Ozone SIP Revision until new budgets have been found adequate.

H. Other Clean Air Act Requirements Applicable to Extreme Ozone Nonattainment Areas

In addition to the SIP requirements discussed in sections II.C through II.G of this document, the CAA includes certain other SIP requirements applicable to Extreme ozone nonattainment areas, such as the San Joaquin Valley. In this section, we identify these other requirements and evaluate the compliance by the State and District with respect to them for the San Joaquin Valley for the 2015 Ozone NAAQS.

1. Transportation Control Strategies and Measures To Offset Emissions Increases From Vehicle Miles Traveled

CAA section 182(d)(1)(A) requires, in relevant part, a State to submit, for each area classified as “Severe” or above, a SIP revision that “identifies and adopts specific enforceable transportation control strategies and transportation control measures to offset any growth in emissions from growth in vehicle miles traveled or number of vehicle trips in such area.” ^[169] Herein, we use “VMT” to refer to vehicle miles traveled and refer to the related SIP requirement as the “VMT emissions offset requirement.” In addition, we refer to the SIP revision intended to demonstrate compliance with the VMT emissions offset requirement as the “VMT emissions offset demonstration.” The 2015 Ozone SRR extends the VMT emissions offset requirement to Severe or above areas for the 2015 ozone NAAQS at 40 CFR 51.1302.

On July 27, 2020, CARB submitted the VMT emissions offset demonstrations for certain nonattainment areas for the 2015 ozone NAAQS, including San Joaquin Valley. The SJV 2022 Ozone Plan cites the July 27, 2020 submission by CARB as the basis for compliance with the VMT emissions offset requirement. In 2023, the EPA took final action to approve the VMT emissions offset demonstration element in that submission for the San Joaquin Valley ozone nonattainment area, among other areas, as meeting the requirements of CAA section 182(d)(1)(A) and 40 CFR 51.1302 for the 2015 ozone NAAQS.^[170]

2. Enhanced Vehicle Inspection and Maintenance Programs

CAA section 182(b)(4) requires States with ozone nonattainment areas classified under subpart 2 as Moderate to submit SIP revisions that provide for the implementation of a “Basic” vehicle inspection and maintenance (I/M) program in those areas. CAA section 182(c)(3) requires States with ozone nonattainment areas classified under subpart 2 as Serious or above to submit SIP revisions that provide for the implementation of an “Enhanced” I/M program in certain urbanized portions of those areas.^[171] Because the San Joaquin Valley is Extreme for the 2015 ozone NAAQS, the State of California must implement an Enhanced I/M program in the urbanized portions of the San Joaquin Valley.

As a general matter, Basic and Enhanced I/M programs both achieve their objective by identifying vehicles that have high emissions as a result of one or more malfunctions and requiring them to be repaired. An Enhanced I/M program covers more of the vehicles in operation, employs inspection methods that are better at finding high emitting vehicles, and has additional features to better ensure that all vehicles are tested properly and effectively repaired. The EPA has established specific requirements for Basic and Enhanced I/M programs in 40 CFR part 51, subpart ( printed page 69939) S. These requirements establish minimum performance standards for Basic and Enhanced I/M programs as well as requirements for certain elements of the programs, including, among other elements, test frequency, vehicle coverage, test procedures and standards, stations and inspectors, and data collection, analysis and reporting.^[172]

On April 26, 2023, CARB submitted the Smog Check Certification SIP to the EPA to address I/M SIP requirements for certain nonattainment areas for the 2015 ozone NAAQS, including the San Joaquin Valley. In 2024, the EPA took final action to approve the Smog Check Certification SIP based on our finding that it meets the applicable SIP requirements under the under CAA section 182(c)(3) and 40 CFR 51.1302 for the applicable California nonattainment areas for the 2015 ozone NAAQS, including the San Joaquin Valley.^[173]

3. New Source Review Rules

CAA section 182(a)(2)(C) requires States to submit SIP revisions containing permit programs for each of their ozone nonattainment areas. The SIP revisions are to include requirements for permits in accordance with CAA sections 172(c)(5) and 173 for the construction and operation of each new or modified major stationary source for VOC or NO_X anywhere in the nonattainment area.^[174] The 2015 Ozone SRR includes provisions and guidance for nonattainment new source review (NSR) programs.^[175]

In 2023, the EPA took final limited approval and limited disapproval action on the District's nonattainment NSR rule, Rule 2201 (“New and Modified Stationary Source Review Rule”).^[176] In the 2023 final action, we determined that Rule 2201 generally satisfies the applicable CAA and regulatory requirements for sources subject to nonattainment NSR permit program requirements for Extreme ozone nonattainment areas. However, we also determined that Rule 2201 does not fully satisfy all these requirements and identified certain deficiencies that must be corrected. The District amended Rule 2201 and CARB submitted the amended rule to the EPA on October 13, 2023.

In January 2025, the EPA proposed a limited approval and limited disapproval of the amended nonattainment NSR rule based on the preliminary determination that the previously-identified deficiencies had been corrected but also that certain newly-identified deficiencies remain in the rule.^[177] The newly-identified deficiencies in amended District Rule 2201 do not affect our proposed action on the SJV 70 ppb Ozone SIP. We will take final action on the amended District Rule 2201 in a separate rulemaking.

4. Clean Fuels for Fleets Program

CAA sections 182(c)(4)(A) and 246 require States to submit SIP revisions that establish a clean-fuel vehicle program for fleets (referred to herein as a Clean Fuels for Fleets Program (CFFP)) in certain of their ozone nonattainment areas classified as Serious and above. The Federal CFFP is specified in part C of title II of the CAA. CAA section 182(c)(4)(B) allows States to opt out of the Federal CFFP by submitting a SIP revision consisting of a program or programs that will result in at least equivalent long-term reductions in ozone precursors and toxic air emissions. The CFFP SIP requirement applies to the San Joaquin Valley as an ozone nonattainment area with a 1980 population of 250,000 or more and classified as Extreme for the 2015 ozone NAAQS.^[178]

On February 3, 2022, CARB submitted the Clean Fuels for Fleets Certification, a multi-district certification (including the San Joaquin Valley) that California's Low Emission Vehicle program achieved emissions reductions at least equivalent to the reductions that would be achieved by the Federal CFFP and thereby complied with the CFFP SIP requirement for the 2015 ozone NAAQS. In 2023, the EPA approved the Clean Fuels for Fleets Certification as meeting the requirements of CAA sections 182(c)(4) and 246, and 40 CFR 51.1302, for the applicable nonattainment areas, including the San Joaquin Valley, for the 2015 ozone NAAQS.^[179]

5. Gasoline Vapor Recovery

CAA section 182(b)(3) requires States to submit SIP revisions by November 15, 1992, that require owners or operators of gasoline dispensing systems to install and operate gasoline vehicle refueling vapor recovery (“Stage II”) systems in ozone nonattainment areas classified as Moderate and above. California's ozone nonattainment areas implemented Stage II vapor recovery well before the passage of the CAA Amendments of 1990.^[180]

CAA section 202(a)(6) requires the EPA to promulgate standards requiring motor vehicles to be equipped with onboard refueling vapor recovery (ORVR) systems. The EPA promulgated the first set of ORVR system regulations in 1994 for phased implementation by vehicle manufacturers, and since the end of 2006, essentially all new gasoline-powered light and medium-duty vehicles are ORVR-equipped.^[181] CAA section 202(a)(6) also authorizes the EPA to waive the SIP requirement under CAA section 182(b)(3) for installation of Stage II vapor recovery systems after such time as the EPA determines that ORVR systems are in widespread use throughout the motor vehicle fleet. Effective May 16, 2012, the EPA waived the requirement of CAA section 182(b)(3) for Stage II vapor recovery systems in ozone nonattainment areas regardless of classification.^[182] Thus, a SIP submission meeting CAA section 182(b)(3) is not required for the 2015 ozone NAAQS.

6. Enhanced Ambient Air Monitoring

CAA section 182(c)(1) requires States to submit SIP revisions for all ozone nonattainment areas classified as Serious or above that contain measures to enhance and improve monitoring for ambient concentrations of ozone, NO_X, and VOC, and to improve monitoring of emissions of NO_X and VOC in those areas. The enhanced monitoring network for ozone is referred to as the photochemical assessment monitoring station (PAMS) network. The EPA promulgated final PAMS regulations on February 12, 1993.^[183] The San Joaquin Valley is subject to the CAA PAMS network SIP requirement as an Extreme nonattainment area for the 2015 ozone NAAQS pursuant to 40 CFR 51.1302.

On November 10, 1993, CARB submitted to the EPA a SIP revision addressing the PAMS network for six ozone nonattainment areas, including San Joaquin Valley, to meet the ( printed page 69940) enhanced monitoring requirements of CAA section 182(c)(1) and the PAMS regulations for the 1-hour ozone NAAQS. The EPA determined that the PAMS SIP revision met all applicable requirements for enhanced monitoring and approved the PAMS submission into the California SIP.^[184]

Prior to 2006, the EPA's ambient air monitoring regulations in 40 CFR part 58 (“Ambient Air Quality Surveillance”) set forth specific SIP requirements ( see former 40 CFR 52.20). In 2006, the EPA significantly revised and reorganized 40 CFR part 58.^[185] Under revised 40 CFR part 58, SIP revisions are no longer required; rather, compliance with EPA monitoring regulations is established through review of required annual monitoring network plans.^[186] The 2015 Ozone SRR made no changes to these requirements.^[187]

The most recent annual monitoring plan for San Joaquin Valley that the EPA has reviewed is the District's “2025 Air Monitoring Network Plan” (2025 ANP).^[188] The District's 2025 ANP describes the PAMS program that is operating in San Joaquin Valley.^[189] The District currently operates a total of six PAMS sites configured as two networks, one for the Fresno Metropolitan Statistical Area and one for the Bakersfield Metropolitan Statistical Area.^[190] The EPA approved the District's current PAMS network as part of our approval of the District's ANP.^[191]

The SJV 2022 Ozone Plan relies on the District's then-most recent ANP as the submission that demonstrates that the District meets all Federal ambient monitoring requirements.^[192] We agree that the San Joaquin Valley meets the CAA section 182(c)(1) enhanced ambient monitoring requirement for the 2015 ozone NAAQS based on the District's compliance with the EPA's monitoring regulations in 40 CFR part 58 for PAMS networks and, on that basis, we propose to approve the SJV 2022 Ozone Plan as meeting the enhanced monitoring requirements for the 2015 ozone NAAQS for the San Joaquin Valley under CAA section 182(c)(1) and 40 CFR 51.1302.

7. CAA Section 185 Fee Program

CAA sections 182(d)(3) and 185 require that the SIP for each Severe and Extreme ozone nonattainment area provide that, if the area fails to attain by its applicable attainment date, each major stationary source of VOC and NO_X located in the area shall pay a fee to the State as a penalty for such failure for each calendar year beginning after the attainment date, until the area is redesignated as an attainment area for ozone. These requirements apply to the San Joaquin Valley as an Extreme nonattainment area for the 2015 ozone NAAQS.

The District adopted, and CARB submitted, District Rule 3173 (“Federally Mandated Ozone Nonattainment Fee—2015 8-Hour Standard”) to satisfy the SIP requirements specified in CAA sections 182(d)(3) and 185 for the San Joaquin Valley for the 2015 Ozone NAAQS. We approved District Rule 3173 in July 2026.^[193]

8. Emissions Statement

CAA section 182(a)(3)(B)(i) requires States to submit a SIP revision requiring owners or operators of stationary sources of VOC or NO_X to provide the State with statements of actual emissions from such sources. Statements must be submitted at least every year and must contain a certification that the information contained in the statement is accurate to the best knowledge of the individual certifying the statement. CAA section 182(a)(3)(B)(ii) allows States to waive the emissions statement requirement for any class or category of stationary sources that emit less than 25 tpy of VOC or NO_X, if the State provides an inventory of emissions from such class or category of sources as part of the base year or periodic inventories required under CAA sections 182(a)(1) and 182(a)(3)(A), based on the use of emissions factors established by the EPA or other methods acceptable to the EPA.

The preamble of the 2015 Ozone SRR states that if an area has a previously approved emissions statement rule for a prior ozone NAAQS that covers all portions of the nonattainment area for the 2015 ozone NAAQS, such rule should be sufficient for purposes of the emissions statement requirement for the 2015 ozone NAAQS.^[194] The State should review the existing rule to ensure it is adequate and, if so, may rely on it to meet the emissions statement requirement for the 2015 ozone NAAQS. Where an existing emissions statement requirement is still adequate to meet the requirements of these rules, States can provide the rationale for that determination to the EPA in a written statement certifying that determination in lieu of submitting new revised regulations. States should identify the various requirements and how each is met by the existing emissions statement program. Where an emissions statement requirement is modified for any reason, States must provide the revision to the emissions statement as part of its SIP.

In 2019, the EPA approved Rule 1160 (“Emission Statements”) as meeting the SIP requirements for emission statements for San Joaquin Valley with respect to the prior ozone NAAQS.^[195] On August 3, 2020, CARB submitted the “Emissions Statement Program Certification for the 2015 8-Hour Ozone” for the San Joaquin Valley to the EPA as a SIP revision. In 2023, the EPA approved that SIP revision as meeting the emissions statement requirement under CAA section 182(a)(3)(B) for the San Joaquin Valley for the 2015 ozone NAAQS.^[196]

9. Clean Fuels for Boilers

CAA section 182(e)(3) provides that SIPs for Extreme nonattainment areas require each new, modified, and existing electric utility and industrial and commercial boiler that emits more than 25 tpy of NO_X to either burn as its primary fuel natural gas methanol or ethanol (or a comparably low-polluting fuel) or use advanced control technology, such as catalytic control technologies or other comparably effective control methods.

On August 3, 2021, CARB submitted the “Certification that the San Joaquin Valley Unified Air Pollution Control District's Current Rules Address the Clean Air Act's Clean Fuels for Boilers Requirements for the 2015 8-Hour Ozone Standard” to the EPA as a SIP revision. We approved this certification in 2023.^[197]

10. Contingency Measures for RFP and Attainment

Under CAA section 172(c)(9), States required to make an attainment plan SIP submission must include contingency ( printed page 69941) measures to be implemented if the area fails to meet RFP or to attain the NAAQS by the applicable attainment date. For ozone nonattainment areas classified Serious or above, CAA section 182(c)(9) further specifies that States must include contingency measures to be implemented if the area fails to meet any applicable milestone.

On April 29, 2024, CARB submitted the “Ozone Contingency Measure State Implementation Plan Revision for the 2008 and 2015 8-Hour Ozone Standards” (“2024 SJV Ozone Contingency Measures Plan”) as a revision to the California SIP. The 2024 SJV Ozone Contingency Measures Plan replaces the contingency measure element of the SJV 2022 Ozone Plan.^[198] The EPA will act on the 2024 SJV Ozone Contingency Measures Plan in a separate rulemaking.

III. EPA Review of CARB's Consumer Products Regulations

A. Background

Emissions of VOCs from consumer products contribute to the production of ground-level ozone and particulate matter, which harm human health and the environment. CARB has a long-standing program to reduce VOCs from consumer products, and the EPA has approved at various times the regulations and amendments as revisions to the California SIP.^[199]

CARB's initial staff report states “For more than thirty years, the Board has taken actions pertaining to the regulation of consumer products. Three regulations [Antiperspirants and Deodorants, Consumer Products, and Aerosol Coatings] have set VOC limits for 129 consumer product categories. These three regulations have reduced VOC emissions by about 50 percent between 1990 and 2020 relative to uncontrolled levels.” ^[200]

The requirements in CARB's Consumer Products Regulations apply statewide. CARB predicts that the most recent set of amendments will further reduce statewide VOC emissions by about 8 to 10 tpd by 2031.

B. Summary of the State's Submissions for the Consumer Products Regulations

1. What did California submit?

On April 25, 2023, CARB submitted the following Consumer Products Regulations and Method 310: Title 17 of the California Code of Regulations (CCR), Division 3 (“Air Resources”), Chapter 1 (“Air Resources Board”), Subchapter 8.5 (“Consumer Products”), Article 1 (“Antiperspirants and Deodorants,” “Article 1”); 17 CCR, Division 3, Chapter 1, Subchapter 8.5, Article 2 (“Consumer Products,” “Article 2”), 17 CCR, Division 3, Chapter 1, Subchapter 8.5, Article 3 (“Aerosol Coating Products,” “Article 3”); 17 CCR, Division 3, Chapter 1, Subchapter 8.6 (“Maximum Incremental Reactivity”), Article 1 (“Tables of Maximum Incremental Reactivity (MIR) Values,” “MIR Compound Tables”) and CARB'S Method 310 (“Determination of Volatile Organic Compounds (VOC) in Consumer Products and Reactive Organic Compounds (ROC) in Aerosol Coating Products,” “CARB's Method 310”). Table 10 lists the consumer products regulations and Method 310 with the dates that they were amended and submitted by CARB to the EPA.

( printed page 69942)

CARB submitted the Consumer Products Regulations and Method 310 on April 25, 2023, and the submission was deemed complete by operation of law on October 25, 2023. CARB submitted a supplemental submission for the Consumer Products Regulations on June 25, 2024, and the submission was deemed complete by operation of law on December 25, 2024. We have reviewed both submissions to ensure they meet the completeness criteria in 40 CFR part 51, appendix V.

CARB amended its Consumer Products Regulations in 2021, and Method 310 in 2022, to (1) further reduce VOC emissions to aid in the attainment of the ozone NAAQS, and (2) to correct minor administrative errors and perform non-substantive modifications to the regulations (“CARB's Consumer Products amendments”). CARB's amendments to the Consumer Products Regulations and Method 310 are also intended to fulfill a commitment made by CARB as part of the 2016 State SIP Strategy to reduce VOC emissions from consumer products.^[201]

The amended sections in Article 1 and CARB's Method 310 were composed of administrative revisions such as replacing “ARB” with “CARB” and renumbering sections due to the administrative revisions.

The revisions to Article 2 were more substantive. For example, CARB both revised and added definitions to the regulations, revised the “Table of Standards” to be consistent with the new and revised definitions, and amended to sunset the Two Percent Fragrance Exemption by year 2031 to ensure about 3.0 tpd of VOC emissions reductions statewide. The Two Percent Fragrance Exemption was revised to limit the following categories to a 0.25 percent exemption: “General Purpose Cleaner,” “General Purpose Degreaser,” “Air Freshener,” “Disinfectant,” and “Sanitizer.” CARB also added a calculation for VOC emissions definitions for representative consumer products; revised the requirements to apply for an innovative product exemption (IPE) for Innovative Compressed Gas Propellant Product, or an Innovative Liquefied Propellant Product which allow for manufacturer flexibility; added records requirements for energized electrical cleaner product sales; added special reporting requirements for Personal Fragrance products with less than or equal to 10 percent by weight of combined fragrance ingredients; and made revisions to the test methods section to reflect the revisions in CARB's Method 310.

The revisions to Article 3 included the removal of the aerosol coatings exemption from the Alternative Control Plan ^[202] and the addition of test methods for the determination of the metal content, specular gloss, and acid content of aerosol coating products. The MIR Compound Tables were revised to add the following reactive organic compounds: “Diethyl Carbonate,” “1-Chloro-3,3,3-trifluoropropene; HFO-1233zd,” and “Alkane Mixed—Minimally 90% C13 and higher carbon number” to provide manufacturers the flexibility to create low MIR value products.

We present more information about these regulations in a set of TSDs that we refer to collectively as the “EPA TSDs on CARB's Consumer Products Regulations.” ^[203]

2. Are there other related submissions or actions?

The EPA approved an earlier version of CARB's Consumer Products Regulations into the SIP as follows: Article 1, Article 2, Article 3, MIR Compound Tables, at 85 FR 57703 (Sep. 16, 2020) and CARB'S Method 310 at 86 FR 10016 (Feb. 18, 2021). As noted in Table 10 of this document, CARB adopted revisions to the SIP-approved version on March 25, 2021, and August 1, 2022, and submitted the revisions to the EPA on April 25, 2023.

In its submittal letter, CARB requested that, upon approval of the revised versions of Article 1, Article 2, Article 3, Method 310, and the MIR Compound Tables, the EPA remove the old versions of these regulations from the SIP. In a supplemental submission on June 25, 2024, CARB submitted consumer products Article 2, section 94512 along with additional public process documentation. In this document, we are proposing to approve both the April 25, 2023 submission and the June 25, 2024 supplemental submission. If we finalize this proposed rulemaking, the March 25, 2021 version of Article 1, Article 2, Article 3, and the MIR Compound Tables, as well as the August 1, 2022 version of CARB's Method 310, will replace the previously approved versions of these regulations and test method in the California SIP.

C. The EPA's Review of the State's Submission

1. How is the EPA evaluating the submission?

Emission limitations in the SIP must be enforceable and must not interfere with applicable requirements concerning attainment and RFP or other CAA requirements.^[204] Additionally, 40 CFR part 51, subpart K (“Source Surveillance”) requires SIPs to have enforceable procedures for monitoring the status of compliance with the requirements in the control strategy.

California's Consumer Products Regulations cover VOC area sources. In 1998, the EPA promulgated a national rule to regulate VOC emissions from consumer products ^[205] and, in 2008, the EPA promulgated a national rule to regulate the ozone forming potential of aerosol coating products.^[206] We are comparing the 2021 amendments to CARB's Consumer Products Regulations and the 2022 amendments to Method 310 to the existing SIP requirements and the EPA's national rule to ensure the amendments would not interfere with attainment and RFP or other CAA requirement and to ensure that the State regulations are at least as stringent as the national rule.

Our evaluation also relies on relevant guidance and policy documents to evaluate enforceability, revision/relaxation, and rule stringency requirements.^[207]

( printed page 69943)

2. Does the submission meet the evaluation criteria?

First, we note that CARB has been enforcing the Consumer Products Regulations for decades, and CARB's Consumer Products amendments do not undermine the enforceability of the regulations. Second, CARB's Consumer Products amendments strengthen the SIP and are consistent with the commitment made by CARB in the 2016 State SIP Strategy to reduce VOC emissions from consumer products and thereby contribute to the attainment of the ozone NAAQS in California ozone nonattainment areas. As such, we find that CARB's Consumer Products amendments would not interfere with attainment and RFP or any other requirement of the CAA for the purposes of CAA section 110(l).

Third, when the EPA developed its national consumer products rules in 40 CFR part 59, subpart C (“National Volatile Organic Compound Emission Standards for Consumer Products”) and 40 CFR part 59, subpart E (“National Volatile Organic Compound Emission Standards for Aerosol Coatings”), we reviewed existing consumer products and aerosol coating regulations from States, including those from California.^[208] Since the EPA promulgated its national rules, California has periodically amended its consumer products and aerosol coating rules to add new product categories, combined similar product categories, generally reduced the VOC content limits for consumer products or product-weighted MIR limits for aerosol coatings, and made other amendments to improve implementation and enforcement of its rules. CARB also updated its MIR Compound Tables by including three new low-MIR value categories to provide manufacturers with the flexibility to create low-MIR value products.

The EPA compared CARB's amended regulations to EPA regulations and found that, on the whole, CARB's regulations are generally the same as or more stringent than the national regulations. The EPA has proposed amendments to the National Volatile Organic Compound Emission Standards for Aerosol Coatings Amendments ^[209] to mirror the requirements in Article 3. The EPA notes that, although its national consumer products and aerosol coatings regulations and CARB's regulations are similar, they are not identical. Products will need to comply with the regulations in effect from each agency, and compliance with CARB's rules does not necessarily mean that the product complies with the EPA's national rules. This proposed rulemaking is limited to an evaluation of CARB's amended rules for compliance with the requirements under the CAA and the EPA's regulations for SIP revisions and does not opine on whether a product that meets CARB's rules can also satisfy requirements in the national consumer product rules.

In sum, this proposed action is consistent with EPA regulations, policy, and guidance. The EPA has promulgated a national consumer products regulation and a national aerosol coatings regulation (40 CFR part 59, subparts C and E). There are similarities and differences between the California regulations and the national regulations. The national consumer products and aerosol coatings regulations do not preclude States from adopting more stringent regulations.^[210] In this instance, CARB's Consumer Products Regulations (Article 2) as a whole are both broader and the same as or more stringent than the Federal regulations. With respect to CARB's Consumer Products amendments to Aerosol Coating Products Regulation (Article 3), we propose to find that CARB's Consumer Products amendments contain limits that achieve lower ozone-forming potential relative to the reactivity-based limits for aerosol coating products in the EPA's national aerosol coatings rule. As noted herein, CARB estimates that the current amendments will result in statewide VOC emission reductions of about 8 to 10 tpd by 2031.

We propose to find that these regulations meet CAA requirements and are consistent with relevant guidance regarding enforceability and SIP revisions. The EPA Consumer Products Regulations TSDs have more information on our evaluation and include the EPA's recommendations for the next time CARB amends the regulations.

IV. Proposed Action and Public Comment

For the reasons discussed in this document, under CAA section 110(k)(3), the EPA proposes to approve the SJV 70 ppb Ozone SIP, which comprises the SJV 2022 Ozone Plan, portions of the 2022 State SIP Strategy, and the 2026 Extreme Ozone SIP Revision and related submission materials as they pertain to the San Joaquin Valley. More specifically, we propose to approve the SJV 70 ppb Ozone SIP as meeting the procedural requirements for SIPs and SIP revisions and the following SIP requirements for the 2015 ozone NAAQS:

• Base year emissions inventory as continuing to meet the requirements of CAA sections 172(c)(3) and 182(a)(1) and40 CFR 51.1315;
• RACM demonstration element as meeting the requirements of CAA section 172(c)(1) and40 CFR 51.1312(c);
• Attainment demonstration element as meeting the requirements of CAA sections 172(c)(6), 182(c)(2)(A), and 182(e)(5) and40 CFR 51.1308; CARB's related commitments to achieve aggregate emission reductions of 38.1 tpd NO_X and 13.6 tpd VOC in the San Joaquin Valley by 2037 (through CARB Resolution 26-5 and CARB Executive Order S-26-006), including 32.4 tpd of NO_X and 12.9 tpd of VOC to be achieved through the development of new control techniques or improvement of existing control technologies under CAA section 182(e)(5); and four control measure commitments by the State identified in Table 5 of this document (as adopted the 2022 State SIP Strategy through CARB Resolution 22-14 and revised by the 2026 Extreme Ozone SIP Revision through CARB Resolution 26-5 and CARB Executive Order S-26-006);
• CARB's commitment to submit, by 2034, contingency measures to be implemented for any emission reduction shortfall relative to its aggregate emission reduction commitments for developing new control techniques or improvement of existing control technologies as meeting the contingency measure requirement in CAA section 182(e)(5);
• ROP demonstration element as meeting the requirements of CAA section 182(b)(1) and40 CFR 51.1310(a)(2); ( printed page 69944)
• RFP demonstration element as meeting the requirements of CAA sections 172(c)(2), 182(b)(1), and 182(c)(2)(B) and40 CFR 51.1310(a)(2)(ii);
• Motor vehicle emissions budgets for the 2026, 2029, 2032, and 2035 RFP milestone years and the 2037 attainment year (see Table 9 of this document) because they are consistent with the RFP and attainment demonstrations for the 2015 ozone NAAQS proposed for approval herein and meet the other adequacy criteria in 40 CFR 93.118(e)(4) and (5); and
• Enhanced monitoring element as meeting the requirements of CAA section 182(c)(1) and40 CFR 51.1302.

With respect to the motor vehicle emissions budgets, we propose to limit the duration of the approval of the budgets to last only until the effective date of the EPA's adequacy finding for any subsequently submitted budgets. We are doing so at CARB's request consistent with 40 CFR 93.118(e)(1). The EPA is also initiating the adequacy process for the budgets included in this SIP submission.

For the reasons discussed in this document, and as authorized in CAA section 110(k)(3), the EPA also proposes to approve the 2021 through 2022 amendments to CARB's Consumer Products Regulations and CARB's Method 310, applicable statewide, because they fulfill all relevant requirements.

The EPA is soliciting public comments on the issues discussed in this document. We will accept comments from the public on this proposal and on the adequacy of these budgets for the next 30 days and will consider relevant comments before taking final action.

V. Incorporation by Reference

In this document, the EPA is proposing to include in a final EPA rule regulatory text that includes incorporation by reference. In accordance with requirements of 1 CFR 51.5, the EPA is proposing to incorporate by reference amendments to California Air Resources Board, Title 17, California Code of Regulations, Division 3, Chapter 1, Subchapter 8.5, Article 1—Antiperspirants and Deodorants, Article 2—Consumer Products, and Article 3—Aerosol Coating Products; Title 17, California Code of Regulations, Division 3, Chapter 1, Subchapter 8.6, Article 1—Tables of Maximum Incremental Reactivity (MIR) Values; and CARB's Method 310, amended on August 1, 2022, which regulate VOC emissions from antiperspirants, deodorants, consumer products, and aerosol coating products. The EPA has made, and will continue to make, these materials available through www.regulations.gov and at the EPA Region IX Office (please contact the person identified in the FOR FURTHER INFORMATION CONTACT section of this preamble for more information).

VI. 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 proposed action merely proposes to approve a State plan as meeting Federal requirements and does not impose additional requirements beyond those imposed by State law. For that reason, this proposed action:

• Is not a significant regulatory action subject to review by the Office of Management and Budget underExecutive Order 12866 (58 FR 51735, October 4, 1993);
• Is not anExecutive Order 14192 (90 FR 9065, February 6, 2025) regulatory action because this proposed action is not significant under Executive Order 12866;
• Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
• Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);
• Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);
• Does not have federalism implications as specified inExecutive Order 13132 (64 FR 43255, August 10, 1999);
• Is not subject toExecutive Order 13045 (62 FR 19885, April 23, 1997) because it proposes to approve a State program;
• Is not a significant regulatory action subject toExecutive Order 13211 (66 FR 28355, May 22, 2001); and
• Is not subject to requirements of section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the CAA.

In addition, the SIP is not approved to apply on any Indian reservation land or in any other area where the EPA or an Indian Tribe has demonstrated that a Tribe has jurisdiction. In those areas of Indian country, the proposed 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).

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

91 FR 69910