ELR Citation: 53 ELR 20099
No(s). 21-1263 (D.C. Cir. Jun 30, 2023)

The D.C. Circuit granted in part and denied in part petitions to review EPA's revisions to designations promulgated in 2018 for northern Weld County, Colorado, and El Paso, Texas, as areas that had attained 2015 ozone pollution standards. The revised designations folded Weld County into the greater Denver marginal nonattainment area, and El Paso into a marginal nonattainment area that included another county. Weld County argued EPA relied on data available in 2018 rather than updated data, and that the data did not support the Agency's revisions. Texas argued El Paso's 2021 nonattainment designation was impermissible because EPA made it effective as of the 2018 attainment designation. The court held that EPA reasonably relied on the same data it had used to make the original designation for Weld County and that the data supported the revised one. But it agreed that El Paso's revised designation was impermissibly retroactive. It denied Weld County's petition, granted Texas' petition, and reversed the revisions insofar as they designated El Paso as a marginal nonattainment area.