Editor's note: Arthur Milnes, an award-winning Canadian journalist, is the Inaugural Fellow in Political History at Queen's University Archives in Kingston, Canada and the editor of "Jimmy and Rosalynn Carter: A Canadian Tribute" (2011 McGill-Queen's University Press and the Queen's School of Policy Studies ). He can be reached at arthur.milnes@sympatico.ca

Kingston, Ontario, Canada (CNN) -- Though Georgia is a continent and an ocean away from the Fukushima Daiichi nuclear plant, we can be confident that an 86-year-old man in that state knows full well the fears the Japanese cleanup crews are experiencing.

The Georgian's name? James Earl Carter, the 39th president of the United States. Almost 60 years ago, and then a young U.S. Naval officer working at the dawn of the nuclear age with the U.S. atomic submarine program, Carter was physically lowered into a damaged nuclear reactor in Chalk River, Ontario, Canada, and exposed to levels of radiation unthinkable today after an accident.

"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, now 86, told me during an interview for my new book in Plains in 2008. "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."

Despite the fears he had to overcome, Carter admits he was animated at the opportunity to put his top-secret training to use in the cleanup of the reactor, located along the Ottawa River northwest of Ottawa.

"It was a very exciting time for me when the Chalk River plant melted down," he continued in the same interview. "I was one of the few people in the world who had clearance to go into a nuclear power plant," he said.

"There were 23 of us and I was in charge. I took my crew up there on the train."

On December 12, 1952, the NRX research reactor at Chalk River Laboratories suffered a partial meltdown. There was a power surge and as a result some fuel rods melted after rupturing. Millions of liters of radioactive water ended up in the reactor building's basement. The crucial reactor's core was left unusable. It was later rebuilt and worked for decades before its retirement in the early 1990s.

At the time, Carter was based in Schenectady, New York, and working closely with Adm. Hyman Rickover on the nuclear propulsion system for the Sea Wolf submarine. He was quickly ordered to Chalk River, joining other Canadian and American service personnel.

When he was running for president in 1975-76, Carter briefly described this experience in his book, "Why Not the Best?"

"It was the early 1950s ... 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. ...

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."

Atomic Energy of Canada, a Crown corporation owned by the federal government in Ottawa, still operates nuclear facilities at Chalk River today but the aging systems have caused political controversy in Canada in recent years.

Carter biographer Peter Bourne, a close friend and adviser to Carter, believes the Chalk River experience had a lasting impact on the president, influencing him when he had to confront nuclear issues while leading the western alliance.

"My sense is that up until that point in his career, (Carter) had approached nuclear energy and nuclear physics in a very scientific and dispassionate way," he told me in a separate interview.

"The Chalk River experience made him realize the awesome and potentially very destructive power he was dealing with. It gave him a true respect for both the benefits but also the devastatingly destructive effect nuclear energy could have. I believe this emotional recognition of the true nature of the power mankind had unleashed informed his decisions as president, not just in terms of having his finger on the nuclear button, but in his decision not to pursue the development of the neutron bomb as a weapon."

In his 1995 foreign policy memoir (co-authored by Ivan Head), "The Canadian Way," the late Canadian prime minister, Pierre Trudeau -- in office from 1968 to 1979 and 1980-1984 -- made it clear that fellow world leaders had great respect for Carter on nuclear and non-proliferation issues due to his pre-White House work in the nuclear field.

In his inaugural address, Carter said he would work towards the goal of ridding the Earth of nuclear weapons, and it is a quest he continues today as a former president.

While in the White House, Carter signed the SALT II nuclear arms limitation agreement with the Soviet Union. According to his memoir, "Keeping Faith," he also asked that Vice President Walter Mondale receive full briefings on his possible role in a nuclear exchange and was shocked to learn that no previous second-in-command had been so informed. "It was obvious to me that ... the president might be incapacitated and (the vice president) had to be fully qualified to assume his duties."

As the Japanese workers struggle in their dangerous work, there's no doubt Jimmy Carter's thoughts and prayers have been directed their way. Unlike most of us, he truly understands their fears.

The opinions expressed in this commentary are solely those of Arthur Milnes.