Board of County Commissioners of Weld County, CO v. EPA, No. 21-1263 (D.C. Cir. 2023)
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The Environmental Protection Agency designated northern Weld County, Colorado and El Paso County, Texas, as areas that had already attained a 2015 ozone pollution standard. But EPA reversed course after Clean Wisconsin v. EPA, 964 F.3d 1145 (D.C. Cir. 2020), remanded these designations. In November 2021, EPA folded northern Weld and El Paso Counties into areas previously designated as not having attained the standard. Weld County contends that EPA improperly relied on data available in 2018 rather than updated data and that the data do not support its adverse designation.
The DC Circuit denied Weld County’s petition for review, granted Texas’s petition for review, and reversed the Final Rule insofar as it designates El Paso County to be a marginal nonattainment area. The court held that EPA reasonably relied on the same data it had used to make the original designation and that the data support the revised one. The court explained that Texas argues that El Paso’s 2021 nonattainment designation was impermissibly retroactive because EPA made it effective as of the 2018 attainment designation. As a result, a statutory deadline for El Paso to attain the governing standard passed some three months before EPA made the nonattainment designation. And missing the deadline triggered adverse legal consequences.
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