(CN) - The Environmental Protection Agency need not face claims over still-unrevised regulations for ground-level ozone pollution, the 9th Circuit ruled Monday.
WildEarth Guardians, Midwest Environmental Defense Center and Sierra Club brought the action in 2011, claiming that the EPA's administrator had a "nondiscretionary duty" under the Clean Air Act to issue such revisions.
U.S. District Judge Yvonne Gonzalez Rodgers in San Francisco sided with the agency, however, and the 9th Circuit affirmed Monday.
The groups had based their appeal on Section 166 of the Prevention of Significant Deterioration program, which they said requires the EPA to publish National Ambient Air Quality Standards (NAAQS) for certain pollutants.
This provision, which was added to the Clean Air Act in 1977, required the EPA to issue standards for the listed pollutants by August 1979. As for pollutants, the agency had no more than two years after the date the NAAQS were promulgated to establish regulations.
The EPA claimed that the statute creates a one-time nondiscretionary duty to issue regulations for pollutants added after August 1977. Since ozone was one of the original pollutants included in the provision, it argued that the duty to issue regulations has been fulfilled.
In rebuttal, the environmentalists argued that the EPA must promulgate new regulations for a pollutant each time it revises the NAAQS for that pollutant.
With both interpretations plausible, the 9th Circuit deemed it moot to decide which one is more correct.
To successfully sue the EPA for allegedly failing to perform a nondiscretionary duty, "the nondiscretionary nature of the duty must be clear-cut - that is, readily ascertainable from the statute allegedly giving rise to the duty," Judge Paul Watford wrote for a three-judge panel.
Section 166(a)'s ambiguity on this point "is enough to preclude the plaintiffs' reliance on § 7604(a)(2) as the jurisdictional basis for their suit," Watford added. "The District Court therefore correctly dismissed plaintiffs' claim under the Clean Air Act's citizen-suit provision for lack of subject matter jurisdiction."
David Bender and Christa Westerberg with McGillivray, Westerberg & Bender of Madison, Wisconsin argued for the plaintiffs.
Robert Lundment and Justice Department attorney Ignacia Moreno argued for the EPA.
Judges William Canby Jr. and William Fletcher joined Watford on the panel.
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