Unhappy? Not arbitrary.

The EPA approved Louisiana’s plan for controlling haze; both environmental and industry groups protested. The Fifth Circuit affirmed the EPA’s approval under the “arbitrary and capricious” standard of review.

As to industry: “We afford ‘significant deference’ to agency decisions involving analysis of scientific data within the agency’s technical expertise. The EPA’s selection of a model to measure air pollution levels is precisely that type of decision. The EPA therefore did not act arbitrarily and capriciously in relying on the CALPUFF model to approve Louisiana’s [statutorily-required] determinations.”

As to environmental groups: “Louisiana’s explanation of its . . . determination . . . omitted two of the five mandatory factors and failed to compare—or even set out—the numbers for the costs and benefits of the control options Louisiana considered. Louisiana also failed to explain how its decision accounted for the EPA-submitted analyses that pointed out substantial flaws in other analyses in the administrative record. But applying the deferential standards of the Administrative Procedures Act to the facts of this case, we hold that the EPA’s approval of Louisiana’s [plan] was not arbitrary and capricious.” Sierra Club v. EPA, No. 18-60116 (Oct. 3, 2019).