21 Juin 2012
June 21, 2012
TOKYO (Kyodo) -- Tokyo Electric Power Co. on Wednesday, in its final report on the Fukushima Daiichi nuclear power plant disaster, admitted it was not sufficiently prepared to deal with tsunami-triggered nuclear accidents, but the utility justified its failure to predict the huge tsunami that hit the complex last year.
The over 10-meter-high tsunami that followed a huge earthquake on March 11, 2011, was "beyond expectations," the report said, reiterating the company's earlier view that the larger-than-expected tsunami was the direct cause of the nuclear crisis, while criticizing the government for interfering in its efforts to bring the nuclear complex under control.
The report is a result of a year-long in-house investigation into the world's worst nuclear accident since the 1986 Chernobyl disaster. But it stopped short of digging deeper into the background of why Tokyo Electric could only make insufficient accident assumptions and left unanswered questions about the accident.
As in the interim report issued in December, the utility known as TEPCO maintained the view that key facilities at the plant withstood the impact of the magnitude 9.0 earthquake, but ensuing tsunami waves flooded electrical equipment and resulted in a loss of power, leading to the failure of reactor cooling systems.
Executive Vice President Masao Yamazaki told a press conference that TEPCO had taken measures to secure safety "to the extent possible," but the tsunami was on "a scale rare in all history."
"Looking back, precautions were not sufficient," he said.
The report also said that not only the utility, but "people concerned in nuclear issues as a whole" were not able to predict that an event largely exceeding their expectations could occur, apparently referring to government bodies and experts involved in issuing assessments on the height of tsunami that could hit the plant.
Responding to criticism that staffers may have not had sufficient understanding of an emergency cooling system at the No. 1 unit called an isolation condenser, TEPCO insisted that they had been receiving training and had sufficient knowledge.
TEPCO, meanwhile, turned its fire on the government's response in the early stage of the nuclear crisis, saying that "unnecessary confusion" was caused for those on the front line by the interference of then Prime Minister Naoto Kan and other people at his office.
Such government behavior "only put the nuclear power plant chief in a dilemma and did not contribute to improve" the situation, it said.
The company's communications activities related to the crisis were also restricted because it had to seek approval from the prime minister's office and the Nuclear and Industrial Safety Agency before making announcements to the public, the report added.
TEPCO said it interviewed around 600 people who were involved in dealing with the crisis, which resulted in the meltdowns of the Nos.1 to 3 reactors at the plant.
The No. 2 reactor is believed to have leaked massive radioactive substances that seriously contaminated areas northwest of the Fukushima plant, although a hydrogen explosion did not take place inside the reactor building. But the report did not specify areas that were damaged.