Summary:
The Environmental Protection Agency (EPA) is proposing to approve a state implementation plan (SIP) revision and redesignation request submitted on November 14, 2023, by the Pennsylvania Department of Environmental Protection (PADEP) on behalf of the Allegheny County Health Department (ACHD). The SIP revision asks the EPA to redesignate the Allegheny County, Pennsylvania area from nonattainment to attainment for the 2010 1-hour primary sulfur dioxide (SO<INF>2</INF>) national ambient air quality standard (NAAQS). The revision also asks the EPA to approve into the SIP Allegheny County's maintenance plan for the 2010 1-hour primary SO<INF>2</INF> standard for the Allegheny County area. This action is being taken under the Clean Air Act (CAA).