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 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 Fourth Circuit stayed a pipeline company's use of a nationwide permit, verified by the Army Corps of Engineers, to carry out construction of the Mountain Valley Pipeline in streams and rivers along the pipeline's route. Environmental groups argued the verification was unlawful because the Corps ...

The Montana Supreme Court affirmed vacatur of a Montana Pollutant Discharge Elimination System (MPDES) permit issued by the Montana Department of Environmental Quality (MDEQ) for a copper and silver mine in the Cabinet Mountains. Environmental groups argued, among other things, that MDEQ unlawfully ...

A district court denied mine owners' motion to dismiss a lawsuit alleging they were in violation of their NPDES permit. A conservation group and the state of Washington argued that the owners had violated the terms of their permit by discharging pollutants in excess of average monthly effluent limit...

A district court vacated EPA's 2019 determination that found no jurisdictional waters under the CWA at a salt production complex bordering the southwestern San Francisco Bay. The Agency argued that the CWA did not apply to the complex because it was converted to salt ponds prior to the Act's passage...

A district court denied a motion to reconsider its 2018 ruling that gave EPA discretion as to how to establish a new TMDL for trash in the Anacostia River. An environmental group argued that little progress had been made since the 2018 ruling and that the court should require the Agency to establish...

In an unpublished opinion, the Ninth Circuit granted in part and denied in part an environmental group's petition to review EPA's approval of the Idaho Pollution Discharge Elimination System (IPDES). Specifically, the court denied the petition with respect to the group's challenges concerning the st...

The Sixth Circuit dismissed as moot a lawsuit seeking to preliminarily enjoin EPA's 2015 Clean Water Rule that clarified the definition of "waters of the United States" under the CWA. Ohio and Tennessee challenged the validity of the rule, arguing it extended the scope of the CWA beyond the reach of...