Blast at nuclear plant was ‘massive’

TOKAI, Ibaraki Pref. — A “massive amount of heat and energy” appears to have been released in the explosion Mar. 11 at a bituminization facility at the state-run nuclear fuel reprocessing plant in Tokai, Ibaraki Prefecture, according to an expert on nuclear science engineering.

Officials of the Power Reactor and Nuclear Fuel Development Corp., which runs the Tokai plant, gave a brief tour late Mar. 13 around the damaged facility for members of an expert panel set up by the Science and Technology Agency.

At the facility, low-level liquid nuclear waste is solidified by being mixed with high-temperature asphalt and packed into drums. It seems like “a massive amount of heat and energy was released in the explosion,” said Akira Kanagawa, a professor emeritus at Nagoya University. Kanagawa was speaking as he was escorted around the facility along with other members of the panel and reporters.

Although Kanagawa declined to comment further on the accident until he can see the conditions inside the facility, he said he suspects a significant amount of energy somehow accumulated between the time when the first small fire broke out at around 10 a.m. Mar. 11 and when the blast occurred some 10 hours later. Damage from the explosion at the facility was conspicuous even from the outside. Twenty-nine of the 40 windows of the four-story, two basement-level building were broken and three steel shutters on the ground level had been holed from the inside.