Approval and Promulgation of Implementation Plans; South Carolina: Prevention of Significant Deterioration and Nonattainment New Source Review; Fine Particulate Matter and Nitrogen Oxides as a Precursor to Ozone

EPA is taking final action to approve three revisions to the South Carolina State Implementation Plan (SIP), submitted by the State of South Carolina, through the South Carolina Department of Health and Environmental Control (SC DHEC), to EPA on December 2, 2010, (for parallel processing) and April 14, 2009, and March 16, 2011. South Carolina provided the final version of the December 2, 2010, parallel processing submittal on March 16, 2011. The SIP revisions approved by this action incorporate updates to South Carolina's air quality regulations under South Carolina's New Source Review (NSR) Prevention of Significant Deterioration (PSD) and Nonattainment New Source Review (NNSR) programs. First, the revisions incorporate a PSD permitting requirement promulgated in the 1997 8-Hour Ozone National Ambient Air Quality Standards (NAAQS) Implementation Rule NSR Update Phase II (hereafter referred to as the "Ozone Implementation NSR Update or "Phase II Rule"). Second, the revisions incorporate NSR provisions relating to the fine particulate matter (PM<INF>2.5</INF>) NAAQS as amended in EPA's 2008 NSR PM<INF>2.5</INF> Implementation Rule (hereafter referred to as the "NSR PM<INF>2.5</INF> Rule"). Third, the revisions incorporate NNSR requirements for calculating emissions reductions that will be used as emission offsets and ensures that those reductions are surplus to other federal requirements. As a result of the third revision, EPA also is taking final action to convert its conditional approval of South Carolina's NNSR permitting program to full approval. EPA is approving South Carolina's March 16, 2011, and April 14, 2009, SIP revisions because they are in accordance with the Clean Air Act (CAA or Act). Additionally, EPA is responding to adverse comments received on EPA's March 15, 2011, proposed approval of South Carolina's December 2, 2010, proposed SIP revision.