Twelve U.S. States, the District of Columbia, and the City of New York have sued the EPA for failing to promulgate regulations controlling GHG emissions from oil refineries. The lawsuit, filed in the U.S. Court of Appeals for the District of Columbia Circuit, arises from EPA's June 24, 2008, revision of the standards governing oil refineries under the Clean Air Act's New Source Performance Standards (NSPS). NSPS regulations govern the emission control technologies that must be implemented by new or modified sources of air pollutants.

During the rulemaking process, EPA had responded to commenters' requests that the new standard incorporate GHG controls by arguing that (1) the Clean Air Act does not mandate that EPA incorporate new GHG controls into NSPS regulations, and (2) GHG emissions present novel issues that "warrant proceeding initially through a more deliberate process . . . than in this source category-specific rulemaking." EPA further explained that "promulgating new performance standards for these air pollutants in this one source category could potentially mandate regulation for numerous other source categories under several other parts of the Act" — the same justification offered by EPA in its July 11 ANPR for arguing that the regulation of GHG emissions from mobile sources under the Clean Air Act is inappropriate. Depending on how it is argued, this new case could subject EPA's argument — which, one suspects, will be repeated by EPA in other contexts — to judicial scrutiny for the first time.

The state parties to the lawsuit are New York, California, Connecticut, Delaware, Massachusetts, Maine, New Hampshire, New Mexico, Oregon, Rhode Island, Vermont and Washington.