The Nuclear Regulatory Commission is downgrading the Pilgrim Nuclear Power Station in Plymouth to one of its lowest performance categories after a series of emergency shutdowns and equipment failures at the power plant.
The NRC took action after an inspection team found that some of the plant's four safety relief valves were so degraded they wouldn't open properly under certain conditions. Commission spokesperson Neil Sheehan says the plant's owner should have been aware of the problem.
"These valves serve to reduce pressure levels inside the reactor vessel after a reactor shutdown to help allow for the cooling down and the injection of water into the reactor vessel," Sheehan said. "So they serve a very important safety function."
The NRC ranks nuclear plants in five safety columns. Pilgrim now moves into the fourth column, making it one of the lowest performing plants in the country when it comes to safety.
"The only other column is 'column 5,' which means you are at risk of being shutdown," Sheehan said. "There are 99 operating power reactors in the US, of those 99, only three would be in this 'column 4'."
Pilgrim workers already have replaced the faulty safety relief valves, and Sheehan said the plant now faces further inspections and oversight.
Lauren Berm is the spokesperson for Entergy Corp, which owns Pilgrim. She said the company is reviewing the NRC's feedback in order to improve the plant's performance.
"Here at Pilgrim Station, we have almost 600 workers who operate the plant safely day in and day out," she said. "And if we ever thought it was not safe to operate, we would cease operations without hesitation."
Pilgrim opponents continue to call for the closing of the power plant. Diane Turco, co-founder of the opposition group Cape Downwiders, said she traveled to the State House Thursday to deliver a letter to Governor Charlie Baker, asking him to use his authority and request that the NRC close Pilgrim before there is another equipment failure.
"We don't need another failure because the last failure might be an accident," she said.
Pilgrim has experienced three unplanned shutdowns this year alone. It's currently operating at full power.