Pursuing the same strategy they used to persuade a court to stop water crossing construction activities for the Mountain Valley Pipeline (MVP) until a broader legal challenge is resolved, a coalition of environmental groups wants to do the same to the Atlantic Coast Pipeline (ACP) project.

The group, including the Sierra Club, West Virginia Rivers Coalition, Appalachian Voices and others, has petitioned the U.S. Court of Appeals for the Fourth Circuit to review ACP’s Nationwide Permit (NWP) 12, which is issued by the U.S. Army Corps of Engineers under Section 404 of the U.S. Clean Water Act.

While the organizations await the outcome of that review, they’ve formally asked the Army Corps to stay the NWP 12 permit. “If the Corps refuses to stay the permit,” the groups said earlier this week, “the coalition will ask the court to do so.”

Last month, the Fourth Circuit granted a motion filed by the groups to stay MVP’s NWP 12 permit, which allows contractors to trench through the bottom of streams and rivers. The Sierra Club earlier this year challenged the validity of MVP’s NWP 12 permit, arguing that the project could not meet a special condition in West Virginia requiring all stream crossings be constructed within 72 hours.

In response to the groups’ challenge, the Army Corps voluntarily issued a limited suspension of the NWP 12 for four river crossings in the state, which has since been lifted. But the Sierra Club and others successfully argued to the court that under Army Corps regulations, all portions of the NWP 12 permit must be stayed, putting nearly 600 MVP waterbody crossings in regulatory limbo.

The group said this week ACP’s water crossing permit suffers from the same defects as the MVP permit. “Specifically, Atlantic Coast’s planned crossing of the Greenbrier River — the longest remaining free-flowing river in the East — will take longer to complete than allowed by law.”

ACP spokesman Aaron Ruby said the company couldn’t comment specifically about the petition for review until it “provides the basis for it in its opening brief.” He said, however, the project’s sponsors “fully stand behind” the NWP 12 permit issued by the Army Corps and ultimately believe it will be “affirmed by the courts.”

ACP is backed by Dominion Energy Inc., Duke Energy, Piedmont Natural Gas and Southern Company Gas. The pipeline would carry 1.5 Bcf/d from West Virginia, through Virginia and North Carolina to Southeast markets. Both MVP and ACP have faced criticism for sharing similar routes and serving similar markets.

Environmental groups, including the Sierra Club, have already had some success challenging ACP. The Fourth Circuit in May vacated a key permit issued by the U.S. Fish and Wildlife Service, stopping some work on the project in Virginia and West Virginia.