Proposed rule · 2026-17501

Air Plan Approval; Kentucky; Louisville Area Limited Maintenance Plan for the 1997 8-Hour Ozone NAAQS

The U.S. Environmental Protection Agency (EPA or Agency) is proposing to approve a State Implementation Plan (SIP) revision submitted by the Commonwealth of Kentucky through the Energy and Environment Cabinet (Cabinet) on behalf of the Louisville Metro Air Pollution Control District (District) via a letter dated June 3, 2024. The SIP revision consists of a Limited Maintenance Plan (LMP) for the Kentucky portion of the bi-state Louisville, Kentucky-Indiana 1997 8- hour ozone maintenance area (the "bi-state Louisville Area"). The Kentucky portion of the bi-state Louisville Area includes the Bullitt, Jefferson, and Oldham Counties of Kentucky (the "Louisville Area"). The EPA is proposing to approve the Louisville Area's LMP because it provides for the maintenance of the 1997 8-hour ozone National Ambient Air Quality Standards (NAAQS) within the bi-state Louisville Area through the end of the second 10-year portion of the maintenance period. The effect of this proposed action would be to make certain commitments related to maintenance of the 1997 8-hour ozone NAAQS in the Louisville Area federally enforceable as part of the Kentucky SIP.