The D.C. Circuit denied a road building association's petition for review challenging EPA's CAA §209(e) regulations, which preempt certain state regulation of nonroad engines. In general…

The D.C. Circuit vacated EPA's new source review (NSR) rule for Indian country, which established a federal implementation plan (FIP) covering all Indian country nationwide except where EPA…

The D.C. Circuit dismissed Arizona's objection to a consent decree that established a timeline for EPA to approve a SIP, or promulgate a federal implementation plan (FIP), that would meet the…

The D.C. Circuit vacated an EPA rule establishing nonconformance penalties (NCPs) for on-highway, heavy-duty diesel engines. NCPs are intended to protect "technological laggards" by…

A district court dismissed Native American and environmental groups' CAA citizen suit asking the court to order EPA to issue a final rule that establishes best available retrofit technology (…

The Michigan Court of Appeals, in an unpublished opinion, upheld the state environmental agency's decision to issue two permits authorizing modifications at a coal-fired power plant. The…

The D.C. Circuit dismissed as moot truck engine manufacturers' lawsuit challenging four certificates of conformity EPA issued to another engine manufacturer pursuant to an interim final rule…

A district court denied industry groups' motion to intervene in a CAA citizen suit concerning EPA's alleged failure to review the ozone NAAQS in a timely manner. The underlying lawsuit…

The Supreme Court of Kansas reversed and remanded the Kansas Department of Health and Environment's decision to issue a prevention of significant deterioration (PSD) permit to a power company…

The Eighth Circuit vacated and remanded EPA's best available retrofit technology (BART) determination for a large power plant in North Dakota, but otherwise upheld EPA's partial…