Fuel rods inside three of Fukushima Daiichi’s reactors melted early in the nuclear crisis, TEPCO says.
Japan’s government and outside experts had previously said that fuel rods at three of the plant’s six reactors had likely melted early in the crisis, but TEPCO had only confirmed a meltdown at the No.1 reactor.
TEPCO officials said a review since early May of data from the plant concluded the same happened to reactors No.2 and 3. Damage to the No.2 reactor fuel rods had begun three days after the quake, with much of the fuel rods eventually melting and collecting at the bottom of the pressure vessel containing them. Fuel rods in the No.3 reactor were damaged by the afternoon of March 13, TEPCO said.
The preliminary finding, which was reported to Japan’s nuclear safety agency, represents part of an initial effort to explain how events at Fukushima spiralled out of control early in the crisis.
TEPCO officials also repeated that the tsunami had disabled power to the reactors and knocked out their cooling capability.
Hidehiko Nishiyama, a spokesman for the government’s Nuclear and Industrial Safety Agency, expressed a similar view. “We don’t think the quake affected the important parts of the plant, such as its cooling capacity,” Nishiyama said, although he added there were still some aspects that needed to be clarified by inspecting the site directly.
That process is likely to make months because of the high radiation readings in areas of the plant, experts have said.
Engineers are battling to plug radiation leaks and bring the plant under control more than two months after the March 11 disaster.
Meanwhile, the government has appointed Yotaro Hatamura, a Tokyo University professor of engineering who has studied how complex systems and designs fail, to head a committee that will investigate the cause and handling of the nuclear crisis.
The moves came as a team of investigators from the International Atomic Energy Agency began a two-week visit to Japan to prepare a report on the accident to be submitted to the United Nations agency in June.