Approval and Promulgation of Air Quality Implementation Plans; Delaware, New Jersey, and Pennsylvania; Determination of Attainment of the 2006 24-Hour Fine Particulate Matter Standard for the Philadelphia-Wilmington, PA-NJ-DE Nonattainment Area

EPA is making a determination of attainment regarding the Philadelphia-Wilmington, PA-NJ-DE fine particulate matter (PM<INF>2.5</INF>) nonattainment area (hereafter referred to as "the Philadelphia Area" or "the Area"). EPA has determined that the Philadelphia Area has attained the 2006 24-hour PM<INF>2.5</INF> National Ambient Air Quality Standard (NAAQS), based upon quality- assured, quality-controlled and certified ambient air monitoring data for the 2008-2010 and 2009-2011 periods. Preliminary data available for 2012 are consistent with continued attainment of the Philadelphia Area. This determination of attainment suspends the requirements for the respective state portions of the Philadelphia Area to submit an attainment demonstration and associated reasonably available control measures (RACM), a reasonable further progress (RFP) plan, contingency measures, and other planning State Implementation Plan (SIP) revisions related to the attainment of the standard for so long as the Area continues to attain the 2006 24-hour PM<INF>2.5</INF> NAAQS. This action is being taken under the Clean Air Act (CAA). This action does not constitute a redesignation to attainment, and the Philadelphia Area will remain designated nonattainment for the 2006 24-hour PM<INF>2.5</INF> NAAQS until such time as EPA determines that the Philadelphia Area, or portion thereof, meets the CAA requirements for redesignation to attainment for the standard, including an approved maintenance plan.