On Aug. 21, 2012, the U.S. Court of Appeals for the D.C. Circuit vacated the most recent regulation adopted by the U.S. Environmental Protection Agency (EPA) to reduce cross-state air pollution from the electric generating sector. The purpose of the regulation was to aid downwind states in achieving attainment of the National Ambient Air Quality Standards (NAAQS) for ozone and fine particulate matter under the Clean Air Act (CAA).
In a 2-1 decision, the D.C. Circuit held that EPA exceeded its statutory authority in adopting the Cross-State Air Pollution Rule (CSAPR or Transport Rule) because (a) the rule would require some upwind states to reduce emissions by more than the states’ contribution to air quality exceedancese.g., ambient air quality that exceeds National Ambient Air Quality Standardsin downwind states (the “good neighbor” provision)1 and (b) the rule denied states the first opportunity to develop regulations to be incorporated into State Implementation Plans (SIPs) to address precursors to ozone and fine particulate emissions in neighboring states prior to EPA’s imposing Federal Implementation Plans (FIPs) on each state. See EME Homer City Generation v. EPA, 2012 WL 3570721 (D.C. Cir. Aug. 21, 2012).
