How Jimmy Carter Stopped The First Nuclear Meltdown (Long Before He Was President)

James Felton

James Felton

Senior Staff Writer

clockDec 17 2021, 10:31 UTC
Jimmy Carter

Jimmy Carter, long after he saved Canada from a nuclear meltdown. Image credit: Mark Reinstein /

A recent tweet has drawn attention to a little-known area of nuclear history: the time Jimmy Carter stopped the first nuclear meltdown, long before he was president.

On December 12, 1952, the NRX research reactor at Chalk River Laboratories, Ontario, Canada, went through a partial meltdown due to mechanical failure and human error. The lab had failed to provide adequate cooling for several experimental fuel rods, resulting in them rupturing and melting, sending 10,000 Curies of fission products flooding into the basement of the reactor building, riding on about a million gallons of cooling water.


It was the first accident of its kind and scale, requiring a large cleanup operation. Enter a young Jimmy Carter, looking pretty heroic.


Carter was called in to lead the cleanup because of his experience building the nuclear propulsion system for the Sea Wolf submarine. He described himself as pretty excited to be leading the team responsible for the operation, as well as being one of the few authorized to go into the nuclear power plant. 

The team had an exact replica of the reactor set up on a nearby tennis court to help their work. Due to the small amount of time they were able to spend in the reactor, every second counted.


"I had only seconds that I could be in the reactor myself. We all went out on the tennis court, and they had an exact duplicate of the reactor on the tennis court. We would run out there with our wrenches and we'd check off so many bolts and nuts and they'd put them back on," he wrote in his book, Why Not the Best?

"And finally when we went down into the reactor itself, which was extremely radioactive, then we would dash in there as quickly as we could and take off as many bolts as we could, the same bolts we had just been practicing on. Each time our men managed to remove a bolt or fitting from the core, the equivalent piece was removed on the mock-up."

The team worked in 90-second shifts, dashing in to perform brief work they had practiced on the tennis court, before replicating the work they had managed to do on the tennis court upon their return. The 90-second rule was designed to limit radiation exposure, but likely wasn't enough, and the team were exposed to more radiation than is ideal.


"We were fairly well instructed then on what nuclear power was, but for about six months after that I had radioactivity in my urine," President Carter told CNN in 2011. "They let us get probably a thousand times more radiation than they would now. It was in the early stages and they didn't know."

Working urgently in short shifts, the team were able to clean up the mess of the first partial meltdown in history, all under the guidance of the future president of the United States.

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