Revisions to the Federal Implementation Plan for the Billings/Laurel, Montana, Sulfur Dioxide 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-R08-OAR-2023-0587; FRL-11571-02-R8] AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: The Environmental Protection Agency (EPA) is revising a Federal Implementation Plan (FIP) applicable to sulfur dioxide (SO 2 ) emissions from four sources located in Billings and Laurel, Montana. Specifically, the EPA is revising a portion of the FIP promulgated by the EPA in 2008 (2008 Billings/Laurel SO 2 FIP) by removing a provision which contained an affirmative defense for exceedances of flare emission limits during malfunctions, startups, and shutdowns. The EPA is taking this action pursuant to the Clean Air Act (CAA). DATES: This rule is effective on February 18, 2025. ADDRESSES: The EPA has established a docket for this action under Docket ID No. EPA-R08-OAR-2023-0587. 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. FOR FURTHER INFORMATION CONT…