TOKYO -- Japan's Nuclear Regulation Authority has stopped just short of granting Tokyo Electric Power Co. Holdings a preliminary pass to restart its Kashiwazaki-Kariwa power plant, taking great pains to determine whether the utility that presided over the Fukushima Daiichi meltdown is fit to operate a nuclear plant again.
Tepco seeks to turn back on the Nos. 6 and 7 reactors at the Niigata Prefecture nuclear plant, which is the world's largest by output but has lain dormant since the 2011 Fukushima catastrophe triggered rigorous nuclear safety inspections nationwide. The NRA has already evaluated the plant on a technological basis, but hit unexpected difficulties in determining whether the company itself is trustworthy -- a step the watchdog has never before taken.
"Tepco is the party that caused the accident," Chairman Shunichi Tanaka said at a meeting of the agency Wednesday, referring to Fukushima. "We must apply a higher level of scrutiny than with other nuclear plant operators."
The Tokyo-based power company had previously resolved to balance decommissioning Fukushima Daiichi with improving safety at Kashiwazaki-Kariwa. At Wednesday's meeting, the NRA codified that approach into safety regulations, and put together ways to make the rules more legally binding. Commissioners further stipulated that the minister of Economy, Trade and Industry -- responsible for guiding Tepco -- would have to oversee the utility's safety measures in order for them to grant preliminary approval.
Some 12 reactors at six nuclear power plants across Japan have passed safety inspections on a solely technological basis. Tepco applied to restart Kashiwazaki-Kariwa in September 2013.
Lingering doubts over Tepco's credibility led the nuclear regulator to investigate the company. In February, key structures at the Niigata plant were found to be insufficiently resistant to earthquakes. When the power company reshuffled its management in June, the NRA held two hearings with the new president, Tomoaki Kobayakawa, citing a "need to confirm the attitude toward safety" at the utility.
NRA commissioners this month began to voice doubt over the reliability of Tepco's word and debate holding the utility more legally accountable. Unofficial approval was expected Wednesday at the earliest, but has been put off. The authority will call Kobayakawa in again before deciding whether to grant preliminary approval, which could now come no sooner than Sept. 27.