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 ...

The Third Circuit denied an environmental group's petitions to review EPA's approval of certain air pollution control technology use at industrial facilities in Pennsylvania. The group argued EPA violated the CAA by focusing exclusively on emissions from those facilities instead of examining their i...

The Third Circuit vacated EPA's 2022 decision to reverse its prior determination and to require an oil refinery in the Virgin Islands to obtain a PSD permit before it can resume operations. The refinery owner petitioned for review, arguing EPA's application of its reactivation policy—under which a...