Proposed rule · 2026-22063

Air Plan Approval and Air Quality Designation; TN; Attainment Plan and Redesignation of the Sullivan County Nonattainment Area for the 2010 1-Hour Primary SO2 NAAQS

The U.S. Environmental Protection Agency (EPA or Agency) is proposing to approve the State of Tennessee's attainment plan for the Sullivan County Nonattainment Area (Sullivan County Area or Area) for the 2010 Sulfur Dioxide (SO<INF>2</INF>) National Ambient Air Quality Standards (NAAQS). Additionally, the EPA is proposing to determine that the Area has attained the 2010 SO<INF>2</INF> NAAQS and to approve Tennessee's maintenance plan for continued attainment. With these approvals, the EPA is proposing to approve Tennessee's comprehensive source-specific SO<INF>2</INF> permitted limits for two facilities in the Area, other control measures, and provisions for Reasonably Available Control Measures (RACM) and Reasonably Available Control Technology (RACT), reasonable further progress (RFP), a modeling demonstration of SO<INF>2</INF> attainment and maintenance, and to approve Tennessee's request to redesignate the Area from nonattainment to attainment of the 2010 SO<INF>2</INF> NAAQS. The EPA is taking these actions in accordance with the Clean Air Act (CAA or Act).