Environmental Protection Agency
The Detroit, Michigan area was redesignated to attainment of the 2015 ozone National Ambient Air Quality Standards (NAAQS) on May 19, 2023. On December 5, 2025, the United States Court of Appeals for the Sixth Circuit vacated the Environmental Protection Agency's (EPA's) redesignation of the Detroit area. Therefore, pursuant to the Court's decision, the EPA is making a technical amendment to the part 81 listing for the Detroit area to reflect the area's designation as nonattainment for the 2015 ozone NAAQS, with a classification of Moderate.
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 81 [EPA-R05-OAR-2022-0004; FRL-13336-01-R5] ( printed page 31953) AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: The Detroit, Michigan area was redesignated to attainment of the 2015 ozone National Ambient Air Quality Standards (NAAQS) on May 19, 2023. On December 5, 2025, the United States Court of Appeals for the Sixth Circuit vacated the Environmental Protection Agency's (EPA's) redesignation of the Detroit area. Therefore, pursuant to the Court's decision, the EPA is making a technical amendment to the part 81 listing for the Detroit area to reflect the area's designation as nonattainment for the 2015 ozone NAAQS, with a classification of Moderate. DATES: This final rule is effective on June 29, 2026. ADDRESSES: The EPA has established a docket for this action under Docket ID No. EPA-R05-OAR-2022-0004. 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, i.e., Confidential Business Information (CBI), Proprietary Business Information (PBI), 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 either through https://www.regulations.gov or please contact the person identified in the FOR FURTHER INFORMATIO…
Other Federal Register documents from the same docket.
Air Plan Approval; Michigan; Redesignation of the Detroit, MI Area to Attainment of the 2015 Ozone Standards
Air Plan Approval; Michigan; Redesignation of the Detroit, MI Area to Attainment of the 2015 Ozone Standards
Air Plan Approval; Michigan; Redesignation of the Detroit, MI Area to Attainment of the 2015 Ozone Standards
Air Plan Approval; Michigan; Redesignation of the Detroit, MI Area to Attainment of the 2015 Ozone Standards
Citation: 91 FR 31953