Water leaks from contaminated water purification system at Fukushima Daiichi Nuclear Power Plant; valve could have been forgotten to shut | NHK

On the seventh, there was an issue on the Fukushima Daiichi Nuclear Power Plant the place water containing radioactive supplies leaked from a contaminated water purification system.The water leaked out as a result of a handbook valve that was speculated to be closed was open. TEPCO believes that the employee could have forgotten to shut the valve and is investigating the trigger.

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