nuclear-news

Active fault under Oi nuclear power plant – restart decision is postponed

Decision on fault under Oi nuclear plant deferred http://www.yomiuri.co.jp/dy/national/T121104002958.htm Jiji Press, 5 Nov 12Nuclear regulators deferred a decision Sunday as to whether an active fault runs under Kansai Electric Power Co.’s Oi nuclear power plant in Fukui Prefecture.

Outside experts who participated in the Nuclear Regulation Authority’s on-site inspection of the plant Friday were divided in their evaluations of whether a crush zone underneath the plant is an active fault. The authority decided to hold another meeting Wednesday.

Mitsuhisa Watanabe, a professor at Toyo University, said he was certain there is an active fault under the Oi plant. But Norio Shigematsu, a research scientist at the National Institute of Advanced Industrial Science and Technology, and Atsumasa Okada, a professor at Ritsumeikan University, said it would be premature to draw a conclusion and called for further surveys.

If the authority determines the crush zone is an active fault, the Oi plant’s No. 3 and No. 4 reactors, currently the only active reactors in Japan, would face a possible shutdown.

The crush zone runs directly under a seawater intake channel to cool the No. 3 and No. 4 reactors in the event of emergencies. If the crush zone moves in an earthquake, the emergency system could become unavailable. In an interim report to the government, Kansai Electric said there are no data suggesting the crush zone is an active fault.

The reactors were brought back online in July. The rest of the country’s 50 reactors remain idled in the wake of the accident at Tokyo Electric Power Co.’s Fukushima No. 1 nuclear power plant.

November 5, 2012 - Posted by Christina Macpherson | Japan, safety