A state court reversed the Maryland Department of the Environment's (MDE's) decision to reissue an NPDES general permit for animal feeding operations without limitations on the discharge of gaseous ammonia. An environmental group argued the permit was deficient under both the CWA and state law becau...

The Fourth Circuit granted a pipeline company's petition to review the North Carolina Department of Environmental Quality's (NCDEQ's) denial of a CWA §401 certification for construction of a natural gas pipeline. The company argued the denial was arbitrary and capricious because NCDEQ did not compl...

The D.C. Circuit denied, 2-1, New Jersey's challenge to a rule promulgated by EPA on remand concerning the CAA's new source review (NSR) program. The state argued that EPA inadequately considered concerns stemming from the predictive and subjective nature of projected emissions calculations and adop...

The Tenth Circuit reversed and vacated a district court order preliminarily enjoining EPA and the Army Corps of Engineers from implementing the 2020 Navigable Waters Protection Rule (NWPR) in Colorado. Colorado argued the agencies violated the APA because the NWPR was not in accordance with the law,...

The Montana Supreme Court reversed, 5-2, a lower court decision reversing the Montana Department of Natural Resources and Conservation's (DNRC's) issuance of a beneficial water use permit for a proposed silver and copper mine beneath the Cabinet Mountains Wilderness. The mining company and DNRC appe...

The Ninth Circuit reversed a district court order staying state law claims in a lawsuit concerning the California Water Resources Board's amendments to its water quality control plan for the San Francisco Bay and Sacramento-San Joaquin Delta system. The U.S. government brought the suit, arguing the ...

The Ninth Circuit affirmed in part and vacated in part a district court's dismissal of a county's complaint in long-standing litigation over appropriation of water in the Walker River Basin. The county argued the public interest and maintenance of the public trust required that water flows reach Wal...

The D.C. Circuit vacated three provisions of EPA's 2018 rule implementing NAAQS for ozone. Environmental groups challenged four provisions of the rule: the interprecursor trading program, a provision allowing states to demonstrate compliance with the CAA's "reasonable further progress" milestone req...

The D.C. Circuit vacated EPA's Affordable Clean Energy Rule that repealed and replaced the Clean Power Plan as a means of regulating power plants' greenhouse gas emissions. A group of public health petitioners sought review of the rule's conclusion that §7411 of the CAA only permitted emission redu...

The Fifth Circuit denied petitions to review EPA's 2018 redesignation of Bexar County, Texas, from attainment to nonattainment and designation of three neighboring counties as attainment/unclassifiable for 2015 ozone NAAQS. Texas argued EPA only had authority to change the state's recommended design...