Inconsistency —> Arbitrary

In a detailed (and remarkably readable) review of EPA regulations of water pollution by steam-electric power plants, the Fifth Circuit vacated and remanded a rule for further agency consideration. In a nutshell: “[F]or five of the six wastewater streams regulated by the final rule . . ., EPA affirmatively rejected surface impoundments as [“Best Available Technology”] ‘because [they] would not result in reasonable further progress toward eliminating the discharge of all pollutants, particularly toxic pollutants.’ And yet, having rejected impoundments as BAT because they would not achieve ‘reasonable further progress’ toward eliminating pollution from those streams, EPA turned around and chose impoundments as BAT for each of those same streams generated before the compliance date. That paradoxical action signals arbitrary and capricious agency action.” (emphasis added, citations omitted). Southwestern Elec. Power Co. v. EPA, No. 15-60821 (April 12, 2019).