Forty years after the worst commercial nuclear power plant accident in United States history unfolded on Three Mile Island in Pennsylvania, the only nuclear power reactor still operating there is preparing to shut down.
The facility, which is near Middletown, Pa., has been losing money, and in a statement on Wednesday, Exelon Generation, the company that owns the plant, said it would be closed by Sept. 30. The company and its employees had been hoping for a subsidy from the state, and when that fell through, a shutdown was the only option, that statement said.
“Today is a difficult day for our employees, who were hopeful that state policymakers would support valuing carbon-free nuclear energy the same way they value other forms of clean energy in time to save TMI from a premature closure,” Bryan Hanson, Exelon’s senior vice president and chief nuclear officer, said in the statement.
A company spokesman said the cost of decommissioning the site was estimated at around $1.2 billion.
The reactor where the accident occurred 40 years ago is not owned by Exelon, and it was dormant long before the company began operating a nearby reactor around two decades ago. But for many residents of the area around Harrisburg, Pa., the words “Three Mile Island” will always evoke memories of that panic.
It was, as The New York Times reported in the aftermath, “an accident that would generate a week of doomsday fear, panicky flight, conflicting statements, noisy demonstrations and intense confusion.”
Disaster struck in the early morning hours of March 28, 1979, when water-coolant pumps failed and a reactor overheated. The temperature kept rising after a stuck valve misled the operators into stopping the flow of emergency cooling water. There was a partial meltdown, and the plant was in crisis for several days. Radiation was purposefully released into the air to relieve pressure within the system.
Public panic was fueled, in part, by the sense that people weren’t getting enough information about what had happened — and what they should do to stay safe.
No immediate deaths or injuries were reported, and studies suggest that long-term physical health effects from the accident have been negligible, though this has been contested. What is clear is that the accident spurred sweeping safety regulations. The damaged reactor on Three Mile Island was never restarted.
Nuclear plants often face opposition from environmentalists, as well as from representatives of competing industries like natural gas. But some Pennsylvania residents, including the nearly 700 workers at the facility, were not happy about the pending closure.
“I think it’s a sad moment for all,” said Richard Drey, the business manager for a local chapter of an electric workers’ union, which represents about 200 people who work at the facility. “We thought there was still hope in keeping the place open. It’s going to have a devastating effect on some of the families.” (Exelon said it would offer jobs to workers who were willing to relocate.)
The plant on Three Mile Island, which sits in the Susquehanna River in Londonderry Township in central Pennsylvania, has been struggling financially for years. Exelon announced as early as 2017 that it would close down the plant “absent needed policy reforms.” Supporters of nuclear energy went after those reforms: Two bills were introduced in the State Legislature that would have steered about $500 million to clean power producers in Pennsylvania, with nuclear plants as the main beneficiaries.
That might have kept Three Mile Island open, but no action was taken on the measures.
Accidents like the one at Three Mile Island make it difficult for nuclear power facilities to present themselves as clean and safe, even though they do not generate planet-warming greenhouse gases. And cheap natural gas from hydraulic fracturing has forced some American nuclear reactors to cease operations.
With these closures comes a new problem: What to do with all of the hazardous waste?
“Nobody believes an island is a suitable site to store radioactive waste,” said Eric Epstein, the chairman of Three Mile Island Alert, a nuclear watchdog group based in Harrisburg, Pa., that was founded two years before the 1979 accident. He said the cleanup efforts on the island should be prioritized, which could bring employment opportunities to people losing their jobs.
“This is not a time for celebration,” he said. “It’s a time for a reality check. When it comes to nuclear, and cleaning up plants, we’re entering a really long and challenging phase.”
According to the World Nuclear Association, a London-based group that promotes nuclear power, there are 98 operating nuclear reactors in the United States. Last year, they accounted for 20 percent of the country’s total electricity output. In Pennsylvania, there are four other power plants operating outside of Three Mile Island.
After the shutdown on Three Mile Island, fuel — the radioactive material generating heat inside of the nuclear reactor — will be moved into a pool of water. A few years after that, the fuel will be moved into dry storage, where it could stay indefinitely or until the federal government takes ownership of the material.
The facility itself will be given decades to cool down, until it is safe for people to dismantle the structures. Exelon estimates that the plan to dismantle large components won’t begin until 2074.
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