Protesters gather outside a public hearing for the Atlantic Coast Pipeline in August at James Madison University in Harrisonburg, Va. (Nikki Fox/Daily News-Record via Associated Press)

For several years, there have been questions about whether the $5.5 billion Atlantic Coast Pipeline that would take natural gas from West Virginia to points southeast is needed.

Richmond-based Dominion Energy, the lead partner in the project, has pitched the 600-mile pipeline as necessary for its customers and argued that it should be given power of eminent domain to push through homeowners’ property. Using the rationale of public need, it is arguing before state regulators that Virginia ratepayers should pay $2.4 billion for the plan.

In September, that logic was turned on its head when an individual attending an energy conference in South Carolina sent an audiotape to the Associated Press.

On the tape, Dan Weekley, a Dominion vice president and general manager, can be heard telling conference attendees that the pipeline, which now is planned to stop at Lumberton, N.C., could be extended to South Carolina and provide nearly a billion cubic feet a day for Palmetto State customers.

That was unsettling news to various environmental and property groups that have vigorously opposed the project. The Federal Energy Regulatory Commission may vote on a permit for it soon. The pipeline still needs water permits from Virginia regulators.

The opposition groups ask why Dominion and partners Duke Energy and the Southern Co. should proceed with their plans supposedly in the public good when it seems a strictly commercial project that won’t benefit Virginia electricity users that much.

One crucial question is how big the pipeline will be. In their arguments before FERC, pipeline developers have testified that 90 percent of the planned capacity of 1.5 billion cubic feet a day has been contracted. Most of it would go to subsidiaries of the pipeline partners.

So where does the extra billion cubic feet a day of gas for South Carolinians come from?

According to ThinkProgress, Dominion spokesperson Jen Kostyniuk said that Weekley was addressing concerns that South Carolina needs more natural gas and gas infrastructure. According to Kostyniuk, “He was asked, ‘What are your long-term plans?’ Weekley responded that the focus is on completing the project as proposed, but it could be expanded in the future.”

Dominion claims there are no plans for expansion, but it could be done by adding more compressor stations along the pipeline route.

The timing is unsettling. Pipeline partners have been advocating for the project for several years but have been vague about who the eventual users would be. Dominion has two new natural-gas-generating stations in the works in southern Virginia but admits those stations could be served by an existing pipeline operated by another company.

Dominion’s project includes a trunk line to the Hampton Roads area, raising questions about possible plans for a liquefied natural gas terminal for exports. The utility already has a similar terminal at Cove Point on the Maryland shore of the Chesapeake Bay. Dominion has steadfastly denied any export plans with the ACP.

So, why are we learning on the eve of a critical FERC vote that this might be a much bigger project than we were led to believe? Why all the legerdemain on markets and regulation and intentions?

FERC is notorious for approving most of the energy projects coming before it. The projects’ owners are guaranteed a generous return on equity — up to 14 percent. Virginia ratepayers may get to foot a big chunk of the pipeline construction costs.

For Dominion, what’s not to like?