ELR Citation: 53 ELR 20134
No(s). 21-9509 (10th Cir. Aug 14, 2023)

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 failed to respond to comments the groups submitted during the rulemaking. The court found no basis to conclude EPA abused its discretion by relying on a small but measurable overall improvement in visibility when considering whether Utah's best available retrofit technology alternative satisfied the mandate for states to submit SIPs addressing regional haze visibility impairment, and that the Agency comprehensively responded to comments challenging the dispersion modeling Utah submitted in support of its revised SIP and adequately explained why it relied on the modeling's results. It denied the groups' petition.