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.
Source
https://www.federalregister.gov/documents/2026/05/29/2026-10768/designation-of-areas-for-air-quality-planning-purposes-michigan-technical-amendmentCanonical document at the regulator. Always cite this URL — not the Vantage detail page — in compliance evidence.