The D.C. Circuit vacated EPA's withdrawal of its determination to regulate perchlorate in drinking water. An environmental group argued EPA lacked the authority to withdraw the determination under the SDWA, and that even if it did have such authority, it acted arbitrarily and capriciously in doing s...

A district court adopted the recommendations of a magistrate judge and vacated portions of NMFS' 2019 biological opinion concerning the incidental take statement that authorized take of southern resident killer whales and chinook salmon resulting from commercial harvest of chinook salmon during trol...

A district court granted environmental groups' motion to preliminarily enjoin a logging project in the Kootenai National Forest. The groups argued the project violated the ESA by failing to adequately consider the impacts of unauthorized motorized access on grizzly bears in the project area. The cou...

The Fourth Circuit, 2-1, vacated a district court ruling in a lawsuit concerning the Army Corps of Engineers' plan for maintaining a dam on the Savannah River. The state of South Carolina argued the Corps' plan violated the Water Infrastructure Improvements for the Nation (WIIN) Act because it would...

A district court granted 24 states' motion to preliminarily enjoin EPA's and the Army Corps of Engineers' 2023 rule revising the definition of "waters of the United States" under the CWA. The states argued the rule violated the APA, the Commerce Clause, the Tenth Amendment, the Due Process Clause, a...

A district court granted Texas' and Idaho's motion to preliminarily enjoin EPA's and the Army Corps of Engineers' 2023 rule revising the definition of "waters of the United States" under the CWA. The states sought to enjoin the rule within their borders, arguing it was unconstitutional and violated ...

A district court denied for lack of jurisdiction the Commonwealth of Kentucky's and business groups' motions to preliminarily enjoin EPA's and the Army Corps of Engineers' 2023 rule revising the definition of "waters of the United States" under the CWA. The court found that plaintiffs failed to show...

The Fourth Circuit vacated the West Virginia Department of Environmental Protection's CWA §401 certification for a proposed pipeline that would transport natural gas from West Virginia to southern Virginia. Landowners and environmental groups petitioned for review of the certification, arguing the ...

The Fourth Circuit denied a petition to review the Virginia Department of Environmental Quality's (DEQ's) and the State Water Control Board's approval of a state water permit for a proposed pipeline that would transport natural gas from West Virginia to southern Virginia. Environmental groups argued...