Japan’s Biggest Nuclear Plant Must Wait Longer for Restart Nod
(Bloomberg) -- A Japanese regional governor who holds sway over the fate of the world’s largest nuclear power plant said security measures at the idled facility had improved since his last visit.
But Hideyo Hanazumi, governor of Niigata prefecture, stopped short of endorsing the restart of the Kashiwazaki Kariwa facility after a tour of the site on Friday — his first visit since 2018. Speaking to local media, he said he would base his decision on whether to support the plant’s relaunch by assessing what he “saw and sensed.”
He said he understood efforts taken by the facility’s owner, Tokyo Electric Power Co., to implement safety measures at the plant, which was idled after the Fukushima disaster nearly 15 years ago. “Security has become significantly stricter,” Hanazumi was quoted as saying by the Nikkei newspaper.

Tepco shares extended their decline to drop as much as 6.7%, the most since Oct. 2, on Friday afternoon, underperforming the 0.8% fall in Japan’s Topix Index.
The much-anticipated restart of the Kashiwazaki Kariwa — or KK — plant would hold enormous significance for Japan, as well as for Tepco. It would mark the first time that the power company has operated a nuclear plant since 2011, when it was also in charge of the Fukushima Dai-ichi facility that suffered a meltdown after the earthquake and tsunami.
Japan once boasted a fleet of 54 nuclear reactors, all of which came offline after the meltdown. Fourteen of 33 commercially available units around the country have since resumed operation after passing stringent regulatory protocols and securing crucial approvals from the local governments that host the plants.
But these approvals can take a long time. The Niigata governor’s comments come at a critical juncture for Tepco, which has spent years trying to restart a portion of its only commercially available nuclear plant. Hanazumi’s nod is the biggest remaining hurdle to the firm’s ambition to restart the plant’s No. 6 unit, some 165 miles (266 kilometers) from Tokyo.
The governor said earlier this week that he also wants to visit the wrecked Fukushima plant, on the opposite coast of Japan, before delivering his verdict on the facility within his own prefecture. This visit has not yet been officially scheduled.
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