No active fault under Oi plant, NRA team says


A team from the Nuclear Regulation Authority said Monday that no active geological faults exist under the key facilities of the Oi nuclear power station in Fukui Prefecture.

The five-member team reached its conclusion after inspecting the Kansai Electric Power Co. facility from November to July and determining that the “F-6 crush zone” fault under one of the facilities is not active.

NRA Commissioner Kunihiko Shimazaki, who personally led the team, said an effective consensus had been formed and that further discussions will be held before it drafts its report to the NRA. The future talks will involve outside experts, he said.

The No. 3 and No. 4 units at Oi are Japan’s only active commercial nuclear reactors. No. 3 was set to be taken offline Monday for a routine checkup and will be followed by No. 4 on Sept. 15, marking only the second time Japan has without atomic power.

To ensure the reactors can be restarted as soon as possible after the checkups, Kansai Electric applied in July for an NRA inspection of the Oi complex under new nuclear safety standards drafted after the Fukushima crisis, which began in March 2011 at Tokyo Electric Power Co.’s Fukushima No. 1 power station in Fukushima Prefecture.

But the new nuclear watchdog hasn’t yet started the inspection because it was busy conducting research on faults and crush zones under the Oi plant. It is now known how long the inspection of the Oi plant will take.