In EME Homer City Generation, L.P., v. EPA, 696 F.3d 7 (2012), the U.S. District Court for the District of Columbia Circuit, in a 2 to 1 decision, vacated the 2011 Cross-State Air Pollution Rule (aka the Transport Rule).  The U.S. Supreme Court, on April 29, 2014, reversed the DC Circuit in EPA v. EME Homer City Generation, L.P., et al., 134 S. Ct. 1584 (2014), during the 2013-2014 Term, holding that the “over-control problem” identified by the DC Circuit did not require invalidation of the rule “on its face”.  However, the Supreme Court also agreed with the DC Circuit that certain “as-applied” challenges to the emissions reductions imposed by EPA on upwind states could be challenged. 

In today’s ruling, in EME Homer City Generation, L.P., v. EPA,  a unanimous Court of Appeals for the District of Columbia Circuit granted several challenges, invalidating the 2014 SO2 emissions budgets imposed on Alabama, Georgia, South Carolina and Texas, and the 2014 ozone-season NOx budgets for Florida, Maryland, New Jersey, New York, North Carolina, Ohio, Pennsylvania, South Carolina, Texas, Virginia, and West Virginia.  These action were vacated without  vacatur, and EPA must reconsider these emissions budgets.  The other, broad-ranging challenges to EPA’s rulemaking (such as not subjecting some changes to notice and comment) were rejected.  This ruling may assure that more challenges follow.