Japan’s Largest Nuclear Plant Delays Restart on Alarm Issue

(Bloomberg) -- Tokyo Electric Power Co. will delay the restart of a reactor in Japan’s largest nuclear power plant, initially planned for Tuesday, following an issue with an alarm that was discovered over the weekend. 

Tepco will push back the resumption of operations at unit No. 6 at its Kashiwazaki Kariwa Nuclear Power Plant, Yutaka Kikukawa, a manager at the facility, said in a press briefing on Monday. The utility hasn’t set a new date for the move, he said. 

Resumption of the Kashiwazaki Kariwa unit — also the biggest nuclear power site in the world — will be a watershed moment for the company, which has not operated an atomic plant since 2011, when its Fukushima facility suffered a meltdown accident following a tsunami. The complex includes seven reactors and is located in Niigata prefecture.

Tepco announced on Saturday that it suspended a control rod withdrawal test at the reactor after an alarm failed to activate. It added on Sunday that there were issues with the alarm’s settings, which have now been fixed and confirmed to be operating properly.

The company is conducting operational checks on the remaining control rods, which are expected to take another day or two, a company spokesperson said by email.

(Updates with details throughout.)

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