Air Plan Partial Approval and Partial Disapproval; Utah; Regional Haze State Implementation Plan for the Second Implementation Period; Air Plan Disapproval; Utah; Prong 4 (Visibility) for the 2015 8-Hour Ozone National Ambient Air Quality Standard

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-R08-OAR-2024-0389; FRL-12173-02-R8] ( printed page 95117) AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: The Environmental Protection Agency (EPA) is partially approving and partially disapproving a regional haze state implementation plan (SIP) revision submitted by the State of Utah on August 2, 2022 (Utah's regional haze SIP submission), to address applicable requirements under the Clean Air Act (CAA) and the EPA's Regional Haze Rule (RHR) for the regional haze program's second implementation period. Additionally, the EPA is disapproving the visibility transport “Prong 4” portion of Utah's infrastructure SIP submission submitted on January 9, 2020, for the 2015 Ozone National Ambient Air Quality Standard (NAAQS). The EPA is taking these actions pursuant to the CAA. DATES: This rule is effective on January 2, 2025. ADDRESSES: The EPA has established a docket for this action under Docket ID No. EPA-R08-OAR-2024-0389. 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.…