The U.S. Court of Appeals for the D.C. Circuit vacated EPA’s Close-Out Rule, which allowed upwind states to continue emitting ground-level ozone pollution that significantly contributes to downwind air quality problems. The agency justified the rule by falling back on its analysis from the Cross-State Update, a prior rule that had provided only a partial remedy to interstate emissions. We filed an amicus brief, which argued that EPA fundamentally misunderstood its job in analyzing and choosing between cost-effective options. As the court has now confirmed, EPA has a duty to fully address upwind emissions that contribute significantly to downwind air quality problems and thus cannot rely on its prior, now irrelevant analysis.
Richard Revesz explained in E&E News, Utility Dive, and Bloomberg Law how the ruling upholds an important obligation of the Clean Air Act and may be a precursor of future EPA defeats in court.