Waterford ― The Connecticut Siting Council has refused a petition by Dominion Energy Nuclear Connecticut that would allow it to modify the boundaries of the Millstone Power Station so a controversial data center could be built there.

After six months of deliberation, the council voted last week to decline Dominion’s request without prejudice, bringing uncertainty to NE Edge’s proposal to build a 1.5 million-square-foot data center on approximately 55 acres of the Millstone site.

Attorney William McCoy, who represents NE Edge, said Monday the decision to decline the petition without prejudice allows Dominion to file another petition with the council.

If the boundaries had been changed, the town’s Planning and Zoning, Inland Wetlands and Conservation commissions would have controlled the approval process for the data center. With the rejection, the siting council retains the right to approve the project

According to a siting council report, the power station site is designated only for “electrical generating facilities,” which is its jurisdiction.

But since the data center would not be generating energy but rather using about 15% of the plant’s output to fuel its two buildings, Dominion had to ask the council for a ruling to modify the boundaries of the site to accommodate a different use.

Councilors voted 4-2 on Jan. 4 to not allow the boundary change.

“In addition to the concerns that are mentioned in the staff report, I’m quite hopeful that Millstone will continue operation well into the future as a source of minimal CO2 emissions and reliable energy,” council member Robert Silvestri said.

That staff report recommended that the council decline the boundary modification based on the fact that it would need more time to determine if changing the boundaries would have any negative effects on the environment or state electricity customers’ access to utility services at reasonable costs.

Silvestri added that in the future he would like to see Millstone add to its nuclear power generating assets with things like small nuclear reactors or a revamp of the currently shut down Unit One reactor.

Councilor John Morissette agreed.

“I’m uncomfortable with this request for the site boundary revision given that the site was approved for electric generation facilities, which I think is a valuable asset for the state and I think at this point I’m very uncomfortable approving a request,” he said.

First Selectman Rob Brule said Tuesday that the siting council was “one of the first steps in the regulatory process” for the data center, and that the siting council had said in its decision that it wants more information.

Millstone Site Vice President Michael O’Connor declined to comment.

Concerned Citizens of Waterford and East Lyme

On Monday, Tina Dubosque, a member of Concerned Citizens of Waterford, led a meeting with East Lyme residents who had concerns about the data center.

The Waterford group has said it believes both towns would be affected by the noise, light pollution, safety, environmental and energy security concerns.

About 55 people showed up at the meeting, and about half of them were from East Lyme, the largest turnout from that town at any of the data center meetings thus far. They agreed to join together and form a new group -- the Concerned Citizens of Waterford and East Lyme.

East Lyme First Selectman Dan Cunningham, who was at the meeting, said he was still reviewing information on the data center and would wait to make a judgment. He said it seemed that the data center proposal had not been publicized very widely.

“I suspect that residents of Waterford have more notice because of town meetings,” he said. “I’ve gotten the impression that residents on our side of the river were not very aware of the data center proposal.”

d.drainville@theday.com