Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Redesignation Request and Associated Maintenance Plan for the Pennsylvania Portion of the Philadelphia-Wilmington, PA-NJ-DE Nonattainment Area for the 1997 Annual and 2006 24-Hour Fine Particulate Matter Standard

The Environmental Protection Agency (EPA) is proposing to approve the Commonwealth of Pennsylvania's September 5, 2014 request to redesignate to attainment the Pennsylvania portion of the Philadelphia- Wilmington, PA-NJ-DE nonattainment area (hereafter ``the Philadelphia Area'' or ``the Area'') for both the 1997 annual and the 2006 24-hour fine particulate matter (PM2.5) National Ambient Air Quality Standards (NAAQS or standards). EPA is also proposing to approve as a revision to the Pennsylvania State Implementation Plan (SIP) the associated maintenance plan to show maintenance of the 1997 annual and the 2006 24-hour PM2.5 NAAQS through 2025 for the Pennsylvania portion of the Area. EPA is also proposing to approve the motor vehicle emissions budgets (MVEBs) included in Pennsylvania's maintenance plan for the Pennsylvania portion of the Area for both the 1997 annual and 2006 24-hour PM2.5 NAAQS. EPA is also proposing to determine that the Pennsylvania portion of the Philadelphia Area continues to attain both the 1997 annual and the 2006 24-hour PM2.5 NAAQS. In addition, EPA is proposing to approve the 2007 emissions inventory included in the maintenance plan for the Pennsylvania portion of the Area for the 2006 24-hour PM2.5 NAAQS. In this rulemaking action, EPA also addresses the effects of several decisions of the United States Court of Appeals for the District of Columbia (D.C. Circuit Court) and a decision of the United States Supreme Court: (1) The D.C. Circuit Court's August 21, 2012 decision to vacate and remand to EPA the Cross-State Air Pollution Control Rule (CSAPR); (2) the Supreme Court's April 29, 2014 reversal of the vacature of CSAPR, and remand to the D.C. Circuit Court; (3) the D.C. Circuit Court's October 23, 2014 decision to lift the stay of CSAPR; and (4) the D.C. Circuit Court's January 4, 2013 decision to remand to EPA two final rules implementing the 1997 annual PM2.5 NAAQS. This rulemaking action to propose approval of the 1997 annual and 2006 24-hour PM2.5 NAAQS redesignation request and associated maintenance plan for the Pennsylvania portion of the Philadelphia Area is based on EPA's determination that Pennsylvania has met the criteria for redesignation to attainment specified in the Clean Air Act (CAA) for both the 1997 annual and 2006 24-hour PM2.5 NAAQS. EPA has taken separate rulemaking actions to approve the redesignation of the New Jersey portion and the Delaware portion of the Philadelphia Area for the 1997 annual and 2006 24-hour PM2.5 NAAQS. See 78 FR 54396, September 4, 2013 (for the New Jersey portion of the Area), and 79 FR 45350, August 5, 2014 (for the Delaware portion of the Area).