The court held that a 2002 U.S. Environmental Protection Agency (EPA) rule specifying that Nevada was divided into more than 250 baseline areas for the Clean Air Act (CAA) prevention of significant deterioration (PSD) program was not arbitrary or capricious. Based on an ambiguous 1991 EPA regulation...

The court affirms a district court decision that New York Air Pollution Mitigation Law §66-k is preempted by the Clean Air Act (CAA) Title IV cap-and-trade system and violates the Supremacy Clause of the U.S. Constitution. Section 66-k requires the assessment of an air pollution mitigation offs...

The court holds that an electric utility violated the Clean Air Act (CAA) when it completed 11 construction activities that modified a coal-fired electric-generating facility without first calculating post-construction emissions and obtaining preconstruction CAA prevention of significant deteriorati...

The court reverses and remands a district court's approval of a final environmental impact statement (EIS) that failed to discuss and respond to seven scientific studies casting doubt on the U.S. Forest Service's conclusion that northern goshawks are habitat generalists. In response to the Forest Se...

The court holds that a local transportation control measure, adopted as part of California's state implementation plan to attain federal air quality standards in the San Francisco Bay Area, does not impose an enforceable obligation on the local transportation commission to increase public transit ri...

The U.S. Supreme Court held that certain aspects of local fleet rules do not escape preemption under CAA §209(a) simply because they address the purchase of vehicles rather than their manufacture or sale. The fleet rules prohibit the purchase or lease of vehicles by fleet operators that do not ...

The Sixth Circuit upheld EPA's redesignation of Cleveland, Ohio, from nonattainment to attainment for particulate matter under CAA §107(d)(3)(E). An environmental group argued that EPA illegally waived statutory requirements when it redesignated the area to attainment by not fully approving the...

The U.S. Supreme Court held that the Federal Motor Carrier Safety Administration (FMCSA) did not violate NEPA, relevant CEQ regulations, or the CAA when it failed to evaluate the environmental impact of increased cross-border operations of Mexican motor carriers in its EA because any environmental i...

The Sixth Circuit held that a district court improperly failed to vacate or modify an injunction that prevented the Federal Highway Administration (FHwA) from revisiting its decision regarding a highway extension. An environmental group sued to enjoin construction, stating that the project required ...

The D.C. Circuit held that FERC complied with NEPA in approving a company's application for a certificate of public convenience and necessity to construct a pipeline extension through Southwest Virginia and North Carolina. FERC's process for ventilating and analyzing potential environmental impacts ...