Murray Energy Corp. v. EPA, No. 15-1385 (D.C. Cir. 2019)Annotate this Case
The DC Circuit denied petitions for review of the EPA's 2015 revisions to the primary and secondary national ambient air quality standards for ozone, except with respect to the secondary ozone standard.
The court held that petitioners' arguments, that the primary ozone standard is too lenient because it occasionally permits ozone levels to exceed 0.07 ppm and will allegedly tolerate adverse health effects, lacked merit. However, in regard to the secondary ozone standard, the court held that the EPA has not explained its decision to set a target level of protection against tree growth loss based on a three year average of cumulative, single-year ozone exposures, nor has it justified its decision not to specify any level of air quality requisite to protect against visible leaf injury. Furthermore, the EPA also impermissibly allowed sources that had completed applications for preconstruction permits before the 2015 Rule was adopted to demonstrate compliance with the previous national ambient air quality standards rather than the new, more stringent primary and secondary standards. Accordingly, the court granted those portions of the petition, vacated the grandfathering provision, and remanded for reconsideration.