# Air Plan Approval; Mississippi; 2010 1-Hour SO2 NAAQS Transport Infrastructure

**Action Urgency Score:** 20/100

| Field | Value |
|---|---|
| Agency | Environmental Protection Agency |
| Type | Proposed rule |
| Action | Proposed rule. |
| Published | 2026-08-27 |
| Comments close | 2026-09-17 |
| Significant | No |
| CFR parts | 40 CFR 52 |
| Summary | Pursuant to the Federal Clean Air Act (CAA or the Act), the U.S. Environmental Protection Agency (EPA or Agency) is proposing to approve a State Implementation Plan (SIP) revision submitted by the State of Mississippi, through the Mississippi Department of Environmental Quality (MDEQ), on January 27, 2022, for the purpose of complying with the "good neighbor" provision of the CAA for the 2010 1-hour sulfur dioxide (SO<INF>2</INF>) primary National Ambient Air Quality Standard (NAAQS). The good neighbor provision requires each State's implementation plan to contain adequate provisions prohibiti |
| Document number | 2026-17503 |

## Why this score


Source: Federal Register API (Office of the Federal Register) (https://www.federalregister.gov/documents/2026/08/27/2026-17503/air-plan-approval-mississippi-2010-1-hour-so2-naaqs-transport-infrastructure). Last refreshed: 2026-11-04T09:17:43.641Z.
Data from the Federal Register API; the published Federal Register document is authoritative. Informational only, not legal advice.