(Agence France-Presse) Groundwater radiation levels at Japan’s crippled Fukushima nuclear plant have soared near a tank that leaked 300 tons of toxic water in August, struggling operator Tokyo Electric Power said.

TEPCO said water samples collected from a well on Thursday, October 17 contained 400,000 becquerels per liter of beta-ray emitting substances, the highest reading since the nuclear accident was triggered in March 2011.

Samples in previous days had been showing levels of just 60 to 90 becquerels per liter.

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