On a concrete pad about 25 feet above Plymouth Bay, eight massive steel-reinforced concrete cylinders hold the remains of the radioactive fuel that has kept the Pilgrim Nuclear Power Station running since the 1970s.
When the plant begins decommissioning next year, Pilgrim officials expect to fill another 54 of the so-called dry casks, which are 18 feet tall, weigh 360,000 pounds, and emit small amounts of radiation. The concrete pad is a little more than 200 feet from the shoreline.
The problem is where to store the nuclear waste —
especially since its current location won’t stay 25 feet above Plymouth Bay for long.
As sea levels rise at an accelerating rate, increasing the threat that an extreme storm surge could flood the coastal facility, Pilgrim officials are considering whether to move the spent fuel to higher ground.
Plant officials and federal regulators maintain that the current location is safe, at least for the foreseeable future, noting that the containers are designed to withstand flooding. But local activists are urging Pilgrim to take action, worried that the daunting political obstacles to moving the casks to a federal repository could force them to remain in Plymouth permanently.
“Not moving them would be irresponsible,” said Pine duBois, executive director of the Jones River Watershed Association in Kingston, which is about 8 miles from Pilgrim. “We don’t know if this highly dangerous material will be there for another 100 years or a thousand years. It has to be moved.”
Environmental advocates are calling on the state to require Entergy Corp., the Louisiana-based conglomerate that owns Pilgrim, to move the casks to its helipad or parking lot, which are three times higher than the existing storage site and set further back from the water.
Despite the concerns, plant officials say the casks are secure.
“From our perspective, the pad is now located in a safe place for a long period of time,” said Joseph Lynch, senior government affairs manager for Entergy. “With the pad 25 feet above mean sea level, we still have a significant margin for the highest predicted tides.”
Lynch acknowledged that the existing location was never meant to be permanent. In fact, it was built close to the reactor building because it was designed as a temporary site to offload spent fuel. Pilgrim officials had expected the plant would continue operating through 2032.
Lynch said he has no idea how long the casks will remain in Plymouth.
“I don’t have a crystal ball,” he said.
Under recent worst-case projections, tides could rise as much as 10 feet by the end of the century and as much as 37 feet by 2200. That’s not accounting for storm surges, such as the 15-foot high tides that battered the Massachusetts coast during two nor’easters this winter, causing widespread flooding.
Officials at the US Nuclear Regulatory Commission said they have no reason to believe that the current location is a problem. They note that Pilgrim and the nation’s other nuclear plants were required to reevaluate their vulnerability to flooding in the aftermath of the tsunami that ravaged Japan’s Fukushima nuclear plant in 2011, the worst nuclear disaster since the 1986 meltdown in Chernobyl.
“The NRC is satisfied that Pilgrim’s post-Fukushima flooding reevaluation and the agency’s associated review are reasonable and account for the latest information regarding climate trends, including sea level rise,” said Neil Sheehan, a spokesman for the commission.
Regulators continue to study the risks posed by rising sea levels to the nation’s nuclear plants and their spent fuel, but they say the casks would remain safe even if submerged in water, Sheehan said.
“The NRC’s conservative evaluation of partial or full submersion . . . is that adequate cooling of the spent fuel would be maintained and the fuel would remain in the dry cask storage system,” he said.
The decision about where to store the casks comes as the 46-year-old plant faces a host of maintenance challenges. Entergy announced three years ago that it would close Pilgrim in June 2019, after a litany of economic woes and safety issues. In 2015, the NRC designated Pilgrim as one of the nation’s three least-safe reactors.
Those problems have persisted. Until Thursday, the plant had been offline for 43 days — one of its longest unplanned outages — after crews discovered a significant issue with a transformer that provides power for Pilgrim to operate. It was the second unplanned shutdown this year.
Plant officials must also weigh a range of other issues in deciding whether to move the waste, including security, radiation, and the impact on decommissioning the plant.
Cost is another factor.
Special vehicles are required to move the casks, as are specially built roads that can handle the immense weight. For example, at Vermont Yankee, which began the decommissioning process several years ago, it cost $143 million to fill and move their remaining casks to a new storage site.
Moving the casks uphill would add to the expense, and plant officials have not ruled out building a new storage pad adjacent to the existing one, which is only about 100 feet from the reactor building.
Storing nuclear waste has long been a thorny political issue, one that has become increasingly urgent as more aging plants are shuttered.
Federal officials had long planned to store the waste in a multibillion-dollar repository bored deep into Yucca Mountain in Nevada. But state officials and residents there blocked the site from opening, saying it presents public safety and environmental risks.
Federal officials have been reviewing other options, including opening temporary facilities elsewhere in New Mexico or in Texas. But those options have similar problems: The government would have to overcome local concerns and potential challenges over transporting the fuel through a variety of jurisdictions.
Until then, the waste will remain scattered at plants such as Pilgrim, even well after they shut down.
Baker administration officials declined to answer questions about whether they would press Pilgrim to move the casks to higher ground.
“All siting and construction at the facility must be done in accordance with federal law and regulations, which specify that licensees must design facilities to take into account flood and seismic hazards,” Peter Lorenz, a spokesman for the state Executive Office of Energy and Environmental Affairs, said in a statement.
For local activists who have long raised concerns about the dangers of nuclear power, the assurances of Pilgrim and the NRC provide little comfort.
While the casks may not leak from being submerged for a brief period, they could be subject to corrosion from exposure to saltwater, which could create cracks and eventually lead to leaks, they said.
And if the casks are not moved in the coming decades, or even centuries, they worry about who would ultimately be responsible for protecting the nuclear waste. It’s unlikely, for example, that Entergy will still own the property, they say.
“We need a plan for the next 100 to 300 years,” said Mary Lampert, director of Pilgrim Watch, a civic watchdog group. “I don’t see that happening.”