On March 29, 2013, EPA and several environmental groups filed two separate Petitions for A Writ of Certiorari with the United States Supreme Court, asking the high court to review the D.C. Circuit decision to vacate EPA's Cross-State Air Pollution Rule (the "Transport Rule") in the case of EME Homer City Generation, LP v. Environmental Protection Agency, et al., Case No. 11-1302. EPA and the environmental groups – including Natural Resources Defense Council and Sierra Club – are seeking Supreme Court review almost one month before the deadline to do so, indicating their view that the case is significant and time sensitive.

As previously discussed in this blog, EPA promulgated the Transport Rule to address air pollution (specifically sulfur dioxide ("SO2") and nitrogen oxide ("NOx")) that crosses state lines. On August 21, 2012, the D.C. Circuit vacated the Transport Rule, holding that EPA exceeded its authority when it promulgated the Transport Rule. The D.C. Circuit denied EPA's petition to rehear en banc the 2-1 panel decision to vacate the Transport Rule, leaving the United States Supreme Court as the last chance for the Transport Rule.

EPA and the environmental groups are arguing to the Supreme Court that the D.C. Circuit overstepped its authority when it vacated the Transport Rule. The environmental groups claim that "[t]he court of appeals' decision is riddled with error." In addition, they argue that the Transport Rule presents issues of vital national importance that warrant the high court's review. EPA argues that the D.C. Circuit opinion "creates a substantial impediment to the EPA's authority to implement the [Clean Air Act]" and "hobbles the agency with respect to the aspect of the Act's administration (regulation of interstate pollution that upwind States have little incentive to police on their own) where the need for a strong federal role is the most critical."

Respondents in this case have until April 29, 2013 to file a response to the petitions.

A copy of the EPA's Petition for A Writ of Certiorari is available here, and the environmental groups' Petition for A Writ of Certiorari is available here.