Background
California submitted state implementation plan revisions addressing fine-particulate-matter pollution in the San Joaquin Valley, which has repeatedly failed to meet national ambient air quality standards. The plans included three contingency measures that would impose stricter wood-burning restrictions, expand fugitive-dust controls, and require additional vehicles to undergo smog checks if the Valley failed to make required progress or attain the applicable standards.
The EPA approved the plans even though their projected reductions in nitrogen oxides fell short of both the agency’s longstanding benchmark of one year’s worth of reasonable further progress and its newer, lower benchmark of one year’s worth of progress. The EPA accepted California’s demonstration that additional contingency measures were infeasible. Environmental groups petitioned for review, arguing that Section 172(c)(9) of the Clean Air Act does not authorize such a feasibility exception.
The Court’s Holding
The Ninth Circuit held that the EPA exceeded its statutory authority by reading a feasibility exemption into Section 172(c)(9). Applying independent statutory interpretation under Loper Bright, the majority concluded that although the provision is ambiguous, its best reading does not permit the EPA to excuse inadequate contingency measures based on feasibility. Congress expressly authorized feasibility considerations elsewhere in the Clean Air Act but omitted such language from Section 172(c)(9).
The court also rejected the EPA’s argument that the requirement for “specific” measures that “take effect” without further governmental action implicitly permits feasibility analysis. The majority reasoned that importing such an exception would undermine contingency measures’ function as a backup when existing measures fail. It did not decide whether the proper emissions benchmark is one year’s worth of “progress” or one year’s worth of “reasonable further progress.”
The court remanded without vacating the EPA’s rule because removing the existing contingency measures while the agency reconsidered the matter could cause disruptive consequences. It also determined that petitioners were entitled to litigation costs, including reasonable attorney and expert-witness fees. Judge Bress dissented, arguing that the EPA’s feasibility analysis merely assessed whether proposed measures could satisfy Section 172(c)(9)’s requirements and take effect automatically.
Key Takeaways
- Section 172(c)(9) does not authorize the EPA to approve otherwise insufficient contingency measures based on a feasibility demonstration.
- After Loper Bright, courts independently determine the best reading of ambiguous statutes rather than deferring to an agency’s reasonable interpretation.
- The court left unresolved whether Clean Air Act contingency measures must provide one year’s worth of progress or one year’s worth of reasonable further progress.
- The EPA’s approval remains in effect during remand because the court declined to vacate the rule.
Why It Matters
The decision limits the EPA’s flexibility when reviewing contingency measures for areas that have failed to meet federal air-quality standards. States cannot rely on technological, economic, or implementation constraints to justify contingency measures that fall short of the EPA’s emissions-reduction benchmark unless the statute supports that consideration.
The ruling also illustrates Loper Bright’s practical effect on environmental regulation: statutory ambiguity no longer triggers judicial deference to the EPA. At the same time, remand without vacatur preserves the San Joaquin Valley’s existing contingency measures while the agency reconsiders its approval.