Bill and Lynn Limpert display a poster-sized photo of themselves beside a massive sugar maple at their home in rural Bath County, outside the Capitol Square building in Richmond where Gov. Terry McAuliffe has his office. ( Laura Vozzella/The Washington Post)

Bill and Lynn Limpert rallied outside Gov. Terry McAuliffe’s Capitol Square offices Thursday with a poster-sized photo of themselves back home in rural Bath County, standing at the foot of a massive sugar maple.

Measuring 12 feet around, the tree is part of an old-growth forest that the Limperts said would be removed — along with 38 miles of mountaintop — if Dominion Power is allowed to build a natural gas pipeline through rural Virginia.

The two retirees were part of an environmental protest that claimed Dominion’s proposed Atlantic Coast Pipeline will require “mountaintop removal” — something the company says is not true.

The environmental group Chesapeake Climate Action Network organized the protest to draw attention to a new study it conducted. It concluded that Dominion would have to “decapitate” some mountains along the pipeline’s 600-mile route, which would begin in north-central West Virginia, cross through western and southern Virginia, and end at the southernmost end of North Carolina.

“Dominion Resources intends to blast away, excavate, and partially remove entire ridge tops along 38 miles of Appalachian Mountains as part of the construction of the Atlantic Coast Pipeline,” the study said.

Aaron Ruby, media relations manager for Dominion Energy, said the group is wrong.

“The claims that Chesapeake Climate Action Network has made about mountaintop removal are just totally false,” he said. “It’s a total mischaracterization of how we build pipelines on ridge tops.”

The demonstration came at an awkward time for McAuliffe (D) and the Democrat he would like to succeed him, Lt. Gov. Ralph Northam. Both have said they would support the pipeline if it can meet tough environmental standards. Northam’s rival in the June 13 Democratic primary, former congressman Tom Perriello, opposes the project and has been trying to use his stance to woo liberal voters.

“We found it very interesting that yesterday McAuliffe sends a letter to Trump with 13 other states saying, ‘Honor the Paris climate accord,’ ” said Mike Tidwell, founder and director of the Chesapeake Climate Action Network. “So he’s very focused on an international climate treaty, but appears to be okay with mountaintop removal for a fracked-gas pipeline in his own state.”

McAuliffe was away Thursday on a trade mission to Mexico. His spokesman, Brian Coy, said the governor has the power to stop the pipeline only if environmental studies show that it threatens water quality. Northam recently urged the state’s Department of Environmental Quality to use a tougher, “site-specific” standard to review the project, a move McAuliffe supports.

“He has always said he supports the Atlantic Coast Pipeline; he thinks it will be good for Virginia’s economy,” Coy said. “But it has to be constructed in the most environmentally sensitive way and in a way that’s respectful of the individuals in the communities that are adjacent to the pipeline.”

The study concluded that the pipeline would require that Dominion would have to flatten the ridge top along 38 miles — half in West Virginia, half in Virginia — by 10 to 20 feet in most places. In some places, it said, mountains would have to come down as much as 60 feet.

Ruby said that grading will be required during construction, but the company will be required to fully restore the ridgeline back to its original contours. He provided photographs of what looked like a mountain hiking trail, and said it was a ridge top in Kanawha County, W.Va., which Dominion restored after burying a pipeline there in 2010.

“Like any infrastructure project that you build in mountainous terrain, we’re going to need to grade a relatively limited area on certain ridgelines just so we have enough level surface to safely excavate a 10-foot wide trench,” he said.

The company’s plans call for a 125-foot construction right of way, but he said that much land will not be needed in every stretch of the pipeline.