Regulator stops Tepco nuclear plant restart over security issues

TEPCO has been prevented from restarting units at the Kashiwazaki-Kariwa nuclear plant in Niigata, Japan, as regulators said improvements in security measures must be made following a number of incidents.

According to the World Nuclear Association, prior to the Fukushima Daiichi meltdown in 2011, Japan generated 30% of its electricity from nuclear power with an aim to increase this to 41% by 2017, and 50% by 2030. Following the meltdown at Fukushima Daiichi, Japan’s nuclear reactors were shut down with the first reactor restarts not occurring until 2015. Nine out of 33 operable reactors have been given restart approval, and 16 others are currently in the process of restart approval. The Government’s current aim is to have nuclear power accounting for 20–22% of electricity capacity by 2030.

Tepco – the operator of Fukushima Daiichi – is aiming to restart two of the seven reactors at Kashiwazaki-Kariwa. All units at the power plant are offline but Tepco is prioritising restarting units 6 and 7, which have been offline since March 2012 and August 2011 respectively.

However, there have been a number of security problems at the site, which include unauthorised use of an ID card by an employee to enter the main control room in September 2020, and a contractor damaging intruder detection equipment in January 2021.

According to World Nuclear News, Tepco informed the Nuclear Regulation Authority (NRA) in February that some of this equipment had been repaired but that malfunctions had been detected at other locations on site. However, on inspection of the site by the NRA, it was found that alternative measures implemented by Tepco were not effective and resulted in a long period of time where intruders wouldn’t have been detected.

The NRA has now ruled that Tepco cannot transport nuclear fuel to Kashiwazaki-Kariwa or load fuel rods into the reactors. According to Reuters, Toyoshi Fuketa, Chairman of the NRA, said: "The order is extremely serious as it forbids a nuclear operator to move nuclear fuel materials. There is no time limit for a corrective action order for the protection of nuclear materials. I hope Tepco will take this unprecedented punishment seriously."

In response to the NRA, Tepco apologised for the concern caused over the security issues. It said in a statement: “Tepco takes this regulatory action and the indications from the Nuclear Regulation Authority very seriously. Upper management will take the lead in ascertaining the fundamental causes of this rash of incidents from all perspectives, and engage in drastic reforms.”