A protester calls for measures to contain contaminated water at the Fukushima No. 1 nuclear power plant during a demonstration in front of the prime minister's office on 2 August 2013. Photo: Satoru Ogawa / Asahi Shimbun

6 August 2013 (Asahi Shimbun) – Radioactivity levels soared 47-fold over just five days in groundwater from a monitoring well on the ocean side of the crippled Fukushima No. 1 nuclear power plant, the plant operator said Aug. 5. Tokyo Electric Power Co. said 56,000 becquerels of radioactive substances, including strontium, were detected per liter of groundwater sampled on Aug. 5 in the “No. 1-5” monitoring well, which is adjacent to the turbine building for the No. 1 reactor. The previous measurement for the well water was made on July 31. Highly radioactive water has been detected for some time in groundwater near reactor and turbine buildings of the nuclear plant. A record high level of 900,000 becquerels per liter was found in early July in water taken from a different monitoring well. TEPCO has been struggling to deal with the enormous amounts of water used to cool the damaged reactors and block the flow of contaminated water into the ocean.

Radioactivity levels in Fukushima groundwater increase 47-fold over 5 days