ELR Citation: 53 ELR 20150
No(s). 22-9546 (10th Cir. Sep 18, 2023)

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 2015 ozone NAAQS. The group argued EPA failed to include the state regulations that comprise Colorado's permit program in the rulemaking docket during the public comment period, and acted contrary to law when it approved the revision because the program excludes all "temporary emissions" and “emissions from internal combustion engines on any vehicle” in determining whether a new or modified stationary source is “major” and therefore subject to the permit process, in violation of the CAA. The court found that EPA's notice of proposed rulemaking was adequate under the APA and that there was no problem with the Agency allowing Colorado to exclude emissions from internal combustion engines on any vehicle; but it agreed that the Agency acted contrary to law in allowing Colorado to exclude all temporary emissions under the program. It granted the petition in part, vacated a portion of EPA's final rule, and remanded for further proceedings.