Proposed rule · 2026-06442

Air Plan Approval; Wisconsin; Moderate Attainment Plan Elements for Wisconsin's 2015 Ozone Standard Areas

The Environmental Protection Agency (EPA) is proposing to approve portions of Wisconsin's 2015 ozone National Ambient Air Quality Standard (NAAQS or standard) Moderate nonattainment area State Implementation Plan (SIP) submission for the Wisconsin portion of the Chicago, Illinois-Indiana-Wisconsin area (Kenosha County), the Milwaukee, Wisconsin area, and the Sheboygan County, Wisconsin area. The elements of the Moderate SIP submission include the reasonable further progress (RFP) demonstration and the associated motor vehicle emissions budgets (Budgets) for 2023, the motor vehicle inspection and maintenance (I/M) program, and the nonattainment new source review (NNSR) program. The EPA is also proposing to approve the base year emissions inventory as satisfying previous Marginal area requirements for these areas. The EPA is proposing to approve these portions of the State's submission as a SIP revision pursuant to section 110 and part D of the Clean Air Act (CAA) and EPA's regulations. The EPA is also initiating the adequacy process for the 2023 Budgets.