Proposed rule · 2025-11268

Finding of Failure To Attain; Air Plan Approval; Indiana; Huntington County Sulfur Dioxide Attainment Plan

The Environmental Protection Agency (EPA) is proposing to find that the Huntington County, Indiana nonattainment area failed to attain the 2010 Sulfur Dioxide (SO<INF>2</INF>) National Ambient Air Quality Standard (NAAQS) by the applicable attainment date of April 9, 2023. EPA is also proposing to approve revisions into the Indiana State Implementation Plan (SIP) intended to provide for attainment of the 2010 SO<INF>2</INF> NAAQS for the Huntington County nonattainment area. These SIP submissions include Indiana's attainment demonstration and other planning elements required under the Clean Air Act (CAA), and a Commissioner's Order containing enforceable emission limits. Further, EPA is proposing to find that the provisions of Indiana's SIP submittal adequately provide for attainment of the NAAQS and that the plan meets all other applicable CAA requirements.