Japan's Nuclear Regulation Authority (NRA) has decided to lift an administrative order imposed on Tokyo Electric Power Company (TEPCO) in 2021 that prohibited the company from moving nuclear fuel or loading it into reactors at the seven-unit Kashiwazaki-Kariwa nuclear power plant.
TEPCO applied to NRA for approval of its design and construction plan for Kashiwazaki-Kariwa units 6 and 7 in September 2013. It submitted information on safety upgrades across the site and at those two units to the NRA. These one thousand three hundred and fifty-six megawatt Advanced Boiling Water Reactors began commercial operation in 1996 and 1997. They were the first Japanese boiling water reactors to be put forward for restart following the Fukushima nuclear disaster in 2011.
In 2017, TEPCO received NRA permission to restart units 6 and 7. Local government consent must be acquired before the reactors can be restarted.
In January 2021, TEPCO notified the NRA that a contractor had accidentally damaged intruder detection equipment at the Kashiwazaki-Kariwa site. The company informed the NRA in February that some of the functions related to this equipment had been repaired. TEPCO said it had also found malfunctions in intruder detection equipment at 12 locations on the site and that alternative measures had been implemented. TEPCO told the NRA that three further locations experienced equipment malfunctions. It also reported the unauthorized use of an ID card.
The NRA informed TEPCO in March 2021 that a preliminary assessment had rated the significance of these security lapses as 'red'. This rating is the highest level on its four-point scale of risks in safeguarding nuclear material. This rating suggests a large impact on safety functions or performance. The NRA decided to "suspend for the time being" its pre-use inspections of the plant. These are required for TEPCO to load fuel into Kashiwazaki-Kariwa unit 7.
In April, the NRA issued an administrative order to TEPCO prohibiting it from moving nuclear fuel at the plant until improvements in security measures there have been confirmed by additional inspections.
At the 27 December meeting where the NRA decided to allow TEPCO to restart the requested reactors, the NRA decided to lift the administrative order after inspections confirmed that problems had been dealt with at the Kashiwazaki-Kariwa plant, in Japan's Niigata Prefecture.
Kashiwazaki-Kariwa was not affected by the March 2011 earthquake and tsunami which damaged TEPCO's Fukushima Daiichi plant. The plant's reactors were previously all offline for two to three years following the 2007 Niigata-Chuetsu earthquake, which caused damage to the site but did not damage the reactors themselves. While the units were offline, additional work was carried out to improve the plant's earthquake resistance.
TEPCO has completed work at the other idled units at Kashiwazaki-Kariwa. It is now concentrating its resources on units 6 and 7 while it deals with the clean-up at Fukushima Daiichi. Those two units have been offline for periodic inspections since March 2012 and August 2011, respectively. Restarting those two units would increase the company's earnings by an estimated JPY100 billion (USD706 million) per year.
TEPCO said , “While going back once again to the reflections and lessons learned from the Fukushima Daiichi Nuclear Power Station Accident, we will continue to engage in activities in which all personnel voluntarily engage as we strive to become a nuclear power operator that is trusted by the people of the region and society as a whole.”