Japan Regulator Casts Doubt on TEPCO Nuclear Plant Restart

Yomiuri Shimbun file photo
Tokyo Electric Power Co.’s Kashiwazaki-Kariwa nuclear power plant is seen in Niigata Prefecture.

Issues in the inspection of TEPCO’s Kashiwazaki-Kariwa nuclear power plant are making it difficult for the Nuclear Regulation Authority to approve its restart, the regulator said Wednesday.

Operations at the seven-reactor plant in Niigata Prefecture have been suspended due to deficiencies in Tokyo Electric Power Co.’s antiterrorism measures. A decision on whether to lift the ban on operations is set to be made by the end of May.

In the current situation, “it is quite difficult to lift the ban on operations,” said NRA Chairman Shinsuke Yamanaka at a press conference after the regulator held a meeting.

Prime Minister Fumio Kishida’s goal is to have the reactors restarted in order to have a stable power supply, as the nuclear plant provides electricity to Tokyo.

The Nos. 6 and 7 reactors at the plant have among the largest electricity output in the nation, each at 1,360 megawatts. In 2021, when these reactors were scheduled to be restarted after passing the NRA’s safety review, it was discovered that an employee had used someone else’s ID card to illegally enter the main control room.

It was also found that a number of intrusion detection systems had failed, but that no adequate countermeasures had been put in place.

The NRA then issued a de facto ban on the operation of the Kashiwazaki-Kariwa plant in April that year.

Lifting the ban is a prerequisite for restarting the plant, and the NRA had indicated that it would complete additional inspections as early as this spring.

Of the additional 27 areas for inspection to prevent recurrences, TEPCO has not made sufficient improvements in six of these, including the intrusion detection system and internal awareness of the importance of protecting nuclear materials.

The NRA noted that the number of false alarms, in which detectors went off due to wind, snow or other factors, has not decreased, and that TEPCO has not become an organization that can accurately identify signs of deterioration in the protection of nuclear materials.

Yamanaka, who inspected the plant in January, reportedly said at an NRA meeting: “There has been little improvement in the past month or so. The situation is quite serious.”

During the press conference, Yamanaka said the six items to be checked in the future will include both tangible items and intangible elements. He said that it will take time for the plant to be improved.

“This is not something that can be done in a month or two,” he said, casting doubt on the ban being lifted in May.