EPA Approves Michigan's Plan to Keep St. Clair Air Clean from Sulfur Dioxide Pollution
Official: Air Plan Approval; Michigan; Redesignation and Maintenance Plan for the Partial St. Clair 2010 1-Hour Sulfur Dioxide (SO2) NAAQS Nonattainment Area
Reading: The EPA is approving an existing maintenance plan without tightening standards—the area already attained the 2010 NAAQS, and the plan maintains that attainment status through ongoing monitoring and existing emissions limits.
This federal approval takes effect immediately.
In clear language
The EPA is officially approving Michigan's plan to redesignate a polluted air area near St. Clair as having achieved healthy air quality for sulfur dioxide pollution. Michigan has also submitted and the EPA is approving a maintenance plan to keep that air quality from getting worse, including new emissions limits on a major power plant. This federal approval takes effect immediately.
How does this affect you?
Pick the type of resident or organization you most identify with — we'll generate a plain-language breakdown of what changes for you and what you can do about it.
Who does this affect?
- Residents in southeast Michigan's St. Clair area who breathe the air affected by sulfur dioxide pollution
- DTE Belle River Power Plant and other industrial facilities subject to the new emissions limits
- Michigan's environmental agency, which must implement and monitor the maintenance plan
What can you do?
- Monitor local air quality reports in the St. Clair area to verify air quality improvements continue over time
- Support or participate in public comment periods if Michigan or EPA propose changes to the maintenance plan in the future
Timeline
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- Effective: 2026-07-09
- 2023-12-14: Michigan submitted redesignation and maintenance plan request
- 2025-07-24: Michigan submitted supplemental information
- 2026-04-10: EPA proposed approval
- 2026-07-09: EPA final approval and effective date
No New Jersey official has a verified action on this policy yet.
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