Determination of Attainment by the Attainment Date and Clean Data Determination; California, San Joaquin Valley 1997 Annual PM2.5 Fine Particulate Matter Nonattainment Area

Document Headings Document headings vary by document type but may contain the following: the agency or agencies that issued and signed a document the number of the CFR title and the number of each part the document amends, proposes to amend, or is directly related to the agency docket number / agency internal file number the RIN which identifies each regulatory action listed in the Unified Agenda of Federal Regulatory and Deregulatory Actions See the Document Drafting Handbook for more details. Environmental Protection Agency 40 CFR Part 52 [EPA-R09-OAR-2025-0292; FRL-12825-02-R9] AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: The Environmental Protection Agency (EPA) is finalizing our determination that the San Joaquin Valley, California, fine particulate matter (PM 2.5 ) nonattainment area attained the 1997 annual PM 2.5 national ambient air quality standards (NAAQS) by the December 31, 2024 applicable attainment date. This determination is based on ambient air quality monitoring data from 2022 through 2024. We are also making a clean data determination (CDD) based on the 2022 through 2024 data and our evaluation of preliminary air quality monitoring data from 2025. DATES: This rule is effective March 2, 2026. ADDRESSES: The EPA has established a docket for this action under Docket ID No. EPA-R09-OAR-2025-0292. All documents in the docket are listed on the https://www.regulations.gov website. Although listed in the index, some information is not publicly available, e.g., Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the internet and will be publicly available only in hard copy form. Publicly available docket materials are available through https://www.regulations.gov , or please contact the person identified in the FOR FURTHER INFORMATION CONTACT section for additional availability information. If you need as…