Approval and Promulgation of Implementation Plans; Commonwealth of Kentucky; Prevention of Significant Deterioration and Nonattainment New Source Review Rules: Nitrogen Oxide as Precursor to Ozone

EPA is taking final action to approve a revision to the Commonwealth of Kentucky's State Implementation Plan (SIP), submitted to EPA by the Kentucky Energy and Environment Cabinet, through the Kentucky Division for Air Quality (KDAQ), on February 5, 2010. The revision modifies Kentucky's prevention of significant deterioration (PSD) and nonattainment new source review (NNSR) permitting regulations in Kentucky's SIP to address permit requirements promulgated in the 1997 8-Hour Ozone National Ambient Air Quality Standards (NAAQS) Implementation Rule--Phase II (hereafter referred to as the "Ozone Implementation NSR Update"). The Ozone Implementation NSR Update revised permit requirements relating to the implementation of the 1997 8-hour ozone NAAQS, specifically, incorporating nitrogen oxides (NO<INF>X</INF>) as a precursor to ozone. EPA's approval of Kentucky's provisions to include NO<INF>X</INF> as an ozone precursor into the Kentucky SIP is based on EPA's determination that Kentucky's SIP revision related to these provisions complies with Federal requirements. EPA is also addressing the general adverse comments received on EPA's proposal to approve NO<INF>X</INF> as an ozone precursor for permitting purposes into the Kentucky SIP. The February 5, 2010, SIP revision also included provisions to exclude facilities that produce ethanol through a natural fermentation process from the definition of "chemical process plants" in the NSR major source permitting program in the Kentucky SIP. EPA also received adverse comments for its proposal to approve these provisions. At this time, EPA is not taking final action on Kentucky's provisions to exclude facilities that produce ethanol through a natural fermentation process from the definition of "chemical process plants" in the NSR major source permitting program. EPA will consider the comments received regarding these provisions and take any final action for these provisions in a separate rulemaking.