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Notes on a Meltdown

The presidential commission investigating the Three Mile Island accident learned that the problems rested with people, not technology.
October 20, 2009

By the spring of 1979, when a partial core meltdown at one of two reactors on a long, thin island in Pennsylvania’s Susquehanna River caused a national panic, the movement against nuclear power had been building for decades. (The China Syndrome, the movie thriller about a near-meltdown at an unsafe nuclear plant, came out two weeks earlier.) Not long after the crisis had ended, the editor of the American Nuclear Society’s monthly magazine was forced to concede that Three Mile Island had “put the nuclear industry on probation.” But even he might have been surprised that the probation would last 30 years (see “Nuclear Power Renaissance?).

The investigator: John Kemeny, chairman of the president’s commission on the accident at Three Mile Island, in the control room of the plant two months after the accident.

It was in this atmosphere that President Jimmy Carter appointed a commission to investigate the accident. To head it, he selected John Kemeny, then president of Dartmouth College, a noted mathematician and computer scientist who had also worked on the atomic bomb at Los Alamos. But he was not an expert on nuclear power, and Carter’s pick surprised no one more than Kemeny himself, as he revealed in a June/July 1980 article for TR.

Kemeny and his fellow commissioners quickly came to a surprising finding: they determined that the accident was not the fault of the technology at the plant, which they deemed “amazingly good.”

When we had our first meeting, four weeks after the accident, everyone was saying that it was a very simple case of operator error. The operators had failed to recognize that a certain valve had stuck open, and failure to recognize certain other symptoms led them to turn down the emergency core cooling system. Indeed, there is no question that these emissions converted what should have been a minor incident, that you would never have heard of, into a truly major accident. But I remember vividly, at one of our earliest open hearings, the sworn testimony of these operators, who insisted they’d never been trained for anything of the kind that had confronted them. I didn’t believe them at the time, but before we were through, I would learn that they spoke the truth. They in fact had not been prepared.

This convinced us that the training program for operators should be thoroughly investigated. Some of the training, it turns out, is on the job, and some of it is by contract with producers of the equipment. One witness, the head of training for a manufacturer, was very proud of the significant improvements he had made over the past five years or so in his company’s program. What was the single most important improvement? we asked him. “When I came,” he said, “many of the lectures were given by engineers. But engineers can’t talk so that people can understand them. Therefore, the first rule I laid down was that no engineer is allowed to participate in the training of operators.”

Kemeny concluded that he and his committee members were faced with “one of the most horrendous ‘people problems’ we had ever encountered.”

[W]e reached the unanimous conclusion that fundamental changes were necessary, within both the industry and the Nuclear Regulatory Commission, in people and in attitudes, if you are going to prevent future accidents as serious as Three Mile Island. […] At the same time, we also had to conclude that we did not find any problem that was not curable or that led us to the conviction that nuclear power is too dangerous to exist as a viable energy source. Personally, I had no particular opinion on nuclear power, one way or the other, before chairing this commission. I do have an opinion now: if recommendations like those we came up with are implemented during the next few years, I think nuclear power can be one of the energy alternatives available to humanity. I am equally convinced, however, that if recommendations like ours are not implemented […] then the nuclear power industry will put itself out of business, a victim of its own attitudes.

Carter adopted most of the commission’s recommendations, and no major accident has occurred since at any of the United States’ more than 100 reactors. But no new reactor has been ordered in those 30 years, either. A new licensing process will soon allow for new construction. When ground is broken, the lessons of Three Mile Island will loom large.

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