Dominion Energy said Tuesday it will ask the U.S. Supreme Court to hear its appeal after a lower court refused to reconsider a ruling tossing out a permit that would have allowed the Atlantic Coast Pipeline to cross two national forests, including parts of the Appalachian Trail.

Lead pipeline developer Dominion said it expects the filing of an appeal in the next 90 days. On Monday, the 4th U.S. Circuit Court of Appeals rejected a request for a full-court rehearing from Dominion and the U.S. Forest Service.

A three-judge panel ruled in December that the Forest Service lacks the authority to authorize the trail crossing and had “abdicated its responsibility to preserve national forest resources” when it approved the pipeline crossing the George Washington and Monongahela National Forests, as well as a right-of-way across the Appalachian Trial.

The 605-mile (974-kilometer) natural gas pipeline would originate in West Virginia and run through North Carolina and Virginia.

The appellate ruling came in a lawsuit filed by the Southern Environmental Law Center on behalf of the Sierra Club, Virginia Wilderness Committee and other environmental groups. The denial “sends the Atlantic Coast Pipeline back to the drawing board,” the law center and Sierra Club said in a joint statement on Monday.

The groups said they believe it is impossible to build the pipeline “without causing massive landslides and threatening the Appalachian Trail and our clean water.”

Dominion said it is pursuing “legislative and administrative options” in addition to seeking Supreme Court review.

“We are confident that the U.S. Departments of Interior and Agriculture have the authority to resolve the Appalachian Trail crossing issue administratively in a manner that satisfies the Court’s stated objection,” the company said in its statement.

Dominion said it believes the issue can be resolved in time to allow partial construction work to resume later this year. A company spokesman declined to elaborate on what kind of legislative and administrative remedies Dominion would seek if the Supreme Court declines to hear its appeal.

DJ Gerken, a senior attorney with the Southern Environmental Law Center, said the 4th Circuit’s ruling in December made it clear that the Forest Service lacks statutory authority to issue pipeline right-of-ways over the Appalachian Trail on federal land.

Gerken said Dominion could conceivably ask Congress to give statutory authority to the Forest Service or another federal agency.

“They are trying to avoid going back to the drawing board and doing a responsible job,” Gerken said.