PLYMOUTH — The Pilgrim nuclear station here, the only nuclear power plant left in Massachusetts — and among the worst performers in the country in its final years — was shut down in 2019 after generating electricity for nearly half a century. Cleaning up the radioactive fuel and waste left behind could take another half century. The plant’s new owner, Holtec Decommissioning International, has 60 years to do the job, though it is aiming to finish the work in eight.
One of the next steps could be releasing hundreds of thousands of gallons of radioactive water into Cape Cod Bay.
Removing all of the highly radioactive spent fuel assemblies accumulated since the plant went online is a top-priority step Holtec plans to complete by Dec. 10. Working by remote control, technicians are now loading the assemblies into huge dry steel canisters set into concrete casks, both made by Holtec.
Some 4,000 fuel assemblies — bundles of rods packed with uranium pellets — piled up in the 40-foot-deep spent-fuel pool. This is nearly five times more than it was designed to hold, because the Dept. of Energy did not come through with the nuclear waste removal program it had promised.
There are 340,000 gallons of radioactive water in that pool. Releasing the water into Cape Cod Bay may be the company’s next step, according to Seth Pickering, a deputy regional director for the Mass. Dept. of Environmental Protection.
Pickering is a member of the Nuclear Decommissioning Citizens Advisory Panel (NDCAP), the state board that is reviewing the decommissioning of the nuclear plant. The NDCAP meets every two months. Pickering raised the subject at the group’s Nov. 22 meeting.
There is even more water Holtec needs to dispose of — some one million gallons of it, said Company spokesman Patrick O’Brien. For example, when the reactor was set to be dismantled, the cavity around it was flooded so the work could be done under water. That radioactive water is part of the total.
O’Brien said in a phone interview that “overboarding” the wastewater — that is, disposing of it in a nearby body of water — is one of a few options the company has. It will take another six months to a year, he added, for serious consideration of those options.
Some of the water, after filtering, can be disposed of through an evaporation process. “We have evaporated a large quantity since we started the fuel campaign,” O’Brien said.
Before overboarding it, O’Brien said, “the water would be tested, and we would look for what’s allowable. I know some might be irradiated, but that would be at a very low level.”
At the Nov. 22 meeting, Pickering pointed out that radioactive substances are not listed on the pollutant discharge permit issued to Pilgrim under the federal Clean Water Act and overseen by state and federal agencies.
That means the decision on whether radioactive effluent can be released into Cape Cod Bay would be left entirely to the Nuclear Regulatory Commission (NRC), the federal agency that oversees nuclear reactors. The NRC sets acceptable levels of radioactivity.
Dumping the water is “alarming when we look at the fragility of Cape Cod Bay,” said state Sen. Susan Moran of Falmouth. “I hope there is a long vetting to this plan and complete outreach to the public. And the other options, like trucking, storage, and evaporation, are things the community is entitled to hear all the risks for.”
A spokesman for the Nuclear Regulatory Commission, Neil Sheehan, said in an email that federal regulatory limits for liquid effluent releases from the plant are .06 millirems for the whole human body and .2 millirems for any organ, per month. “To put that into perspective, the average American is exposed to about 620 millirems of radioactivity each year from natural and manmade sources,” Sheehan wrote.
“Most plants perform liquid radioactive effluent releases,” Sheehan said. To achieve what he called the “very conservatively set limits” in federal regulations, there can be batch releases whose radionuclide concentrations have been measured after the liquid is treated by a radioactive waste cleanup system.
During the NDCAP meeting, Pickering said that if the water is released into the bay, it would be done in 20,000-gallon batches.
During the meeting, Duxbury activist and NDCAP member Mary Lampert asked how tritium, a radioactive isotope of hydrogen, would be handled. Tritium is not cleaned up by the resin filtering systems used to treat radioactive wastewater, Lampert said.
Jack Priest, a panel member and director of the radiation control program for the state Dept. of Public Health, agreed with Lampert. “I’m unaware of a filtering mechanism for tritium,” Priest said.
“We will look for concentrations of nuclides [referring to a substance’s nuclear properties] and chemicals in the water,” said John Moylan, a panel member and the Pilgrim’s site vice president. “That will drive processes for cleaning the water up and disposing of it.”
“We are going to see what the plan actually ends up being,” Pickering said. “We will have to see what would be included in the discharge and go from there.” The state agencies will have some ability to regulate any pollutants that do fall under the Clean Water Act, he said.
State Rep. Sarah Peake of Provincetown called any plan to discharge radioactive substances into the bay “a terrible idea.”
“I hope our friends at the Conservation Law Foundation will bring suit with the same zeal that they have against municipalities over wastewater issues,” Peake said. The organization currently has suits against Barnstable and Mashpee.
Diane Turco, founder and director of the Cape Downwinders, a watchdog group, called any plan to discharge the water into the bay “beyond negligent and irresponsible.”
“Cheap and fast is the Holtec business model,” Turco said via email after the meeting. “Public and environmental health and safety is not a Holtec priority.”
During a phone interview, Lampert agreed. “Whether they do the right thing will depend on public protest,” she said. “They need to follow the example of Vermont Yankee and truck it off site to a place suitable to store it.” Effluent from the Yankee plant was trucked to an Idaho facility for storage.
State Sen. Julian Cyr of Truro filed provisions to fund continued monitoring of the bay throughout Pilgrim’s decommissioning in two state budgets that were approved by the Senate but didn’t make it through the House, despite support from Rep. Peake.
“We don’t actually know what’s going on around the plant,” Cyr said. “Until we have routine monitoring, absolutely no way in hell should there be any discharge.”
