A district court granted summary judgment for several bus companies in a CAA citizen suit alleging that the companies excessively idled their buses in violation of Massachusetts and Connecticut law. The companies moved for summary judgment, asserting the group lacked standing. The court found the co...

The Tenth Circuit, 2-1, granted in part an environmental group's challenge to EPA's approval of a Colorado SIP revision certifying that the state's existing, EPA-approved nonattainment new source review permitting program for the Denver Metro-North Front Range area met the requirements for attaining...

The Tenth Circuit affirmed in part and vacated in part EPA's partial approval and partial disapproval of Wyoming's SIP addressing emissions at coal-fired power plants to reduce regional haze. EPA approved the SIP as to the Naughton plant, but disapproved it for the Wyodak plant, and substituted, thr...

The Tenth Circuit denied environmental groups' petition to review approval of Utah's July 2019 revised SIP addressing regional haze. The groups argued EPA abused its discretion by approving the SIP because Utah's alternative measure did not satisfy CAA national visibility goals, and that the Agency ...