Three Mile Island Accident - Aftermath - Investigations

Investigations

Several state and federal government agencies mounted investigations into the crisis, the most prominent of which was the President's Commission on the Accident at Three Mile Island, created by Jimmy Carter in April 1979. The commission consisted of a panel of twelve people, specifically chosen for their lack of strong pro- or anti-nuclear views, and headed by chairman John G. Kemeny, president of Dartmouth College. It was instructed to produce a final report within six months, and after public hearings, depositions, and document collection, released a completed study on October 31, 1979. The investigation strongly criticized Babcock and Wilcox, Met Ed, GPU, and the NRC for lapses in quality assurance and maintenance, inadequate operator training, lack of communication of important safety information, poor management, and complacency, but avoided drawing conclusions about the future of the nuclear industry. The heaviest criticism from the Kemeny Commission concluded that "fundamental changes were necessary in the organization, procedures, practices 'and above all – in the attitudes' of the NRC " Kemeny said that the actions taken by the operators were "inappropriate" but that the workers "were operating under procedures that they were required to follow, and our review and study of those indicates that the procedures were inadequate" and that the control room "was greatly inadequate for managing an accident."

The Kemeny Commission noted that Babcock and Wilcox's PORV valve had previously failed on 11 occasions, nine of them in the open position, allowing coolant to escape. More disturbing, however, was the fact that the initial causal sequence of events at TMI had been duplicated 18 months earlier at another Babcock and Wilcox reactor, the Davis-Besse Nuclear Power Station owned at that time by Toledo Edison. The only difference was that the operators at Davis-Besse identified the valve failure after 20 minutes, where at TMI it took 80 minutes; and the Davis-Besse facility was operating at 9% power, against TMI's 97%. Although Babcock engineers recognised the problem, the company failed to clearly notify its customers of the valve issue.

Upon his return to Dartmouth, Kemeny addressed Dartmouth college students. When asked what caused the meltdown, he replied that the proximate cause would probably never be known. The Government Affairs Vice President confirmed that the Metropolitan Edison Company, which operated the company, had shortly before received a warning from the Nuclear Regulatory Commission (NRC) that Babcock and Wilcox reactor valves were vulnerable to failure under certain conditions. He said he had sent it on to the Vice President of Engineering, who confirmed that he had read it. Shortly after that, the two men met at the water cooler where the Government Affairs VP asked the Engineering VP a question. The Government Affairs VP remembered the question as "Is there a problem here?" The Engineering VP thought the question was "Have you solved the problem?" Both VPs agreed that the answer was "no". One walked away believing that the problem was solved. The other believed that he had informed his bosses that there was a problem. The issue was never resolved. Kemeny told the students that he believed it never would be. The proximate cause of the meltdown remains unknown and no proof of negligence was ever uncovered.

The Pennsylvania House of Representatives conducted its own investigation, which focused on the need to improve evacuation procedures.

In 1985, a television camera was used to see the interior of the damaged reactor. In 1986, core samples and samples of debris were obtained from the corium layers on the bottom of the reactor vessel and analyzed.