Proposed rule · 2026-14902

Air Plan Approval; Pennsylvania; Harrisburg-Lebanon-Carlisle-York Maintenance Area, Second 10-Year Maintenance Plan for the 2006 Fine Particulate Matter National Ambient Air Quality Standard

The Environmental Protection Agency (EPA) is proposing to approve under the Clean Air Act (CAA), the Second Maintenance Plan for the Harrisburg-Lebanon-Carlisle and York Maintenance Area (Harrisburg- York Area) for the 2006 Fine Particulate Matter national ambient air quality standard (NAAQS) (Second 10-Year Maintenance Plan) as a revision to the state implementation plan (SIP). The SIP revision, submitted on February 7, 2025 by the Pennsylvania Department of Environmental Protection (PADEP), addresses the second 10-year maintenance period for particulate matter with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers ([micro]m), commonly known as fine particulate matter or PM<INF>2.5</INF>. The Plan includes, among other elements, a base year emissions inventory, a maintenance demonstration, contingency provisions, and motor vehicle emissions budgets for use in transportation conformity determinations, to ensure the continued maintenance of the 2006 PM<INF>2.5</INF> NAAQS. The EPA is also proposing to find adequate and approve the motor vehicle emission budgets for the Harrisburg-York Area.