|Japan raises alarm over massive leak of deadly radioactive water at Fukushima nuke plant
Japan's nuclear regulator upgraded its evaluation of a massive volume of radioactive water leak at the wrecked nuclear plant in Fukushima to a level three “serious incident.’’ (pictured, storage tanks at the Fukushima Dai-ichi at Okuma in Fukushima prefecture).
The assessment, on an international scale of zero to seven with seven being the worst, came after operator Tokyo Electric Power Company (TEPCO) said some 300 tons of radioactive water was believed to have leaked from a tank at the Fukushima Daiichi nuclear power plant.
It was the worst such leak since the crisis began in March 2011 when a quake-generated tsunami knocked out reactor cooling systems and sparked meltdowns.
Japan's Nuclear Regulation Authority raised the evaluation from level one, which means “anomaly'' on the UN's International Nuclear Event Scale.
Level three cases on the INES scale are described as “serious incidents'' with “exposure in excess of 10 times the statutory annual limit for workers.’’
The radioactive water leaked from a 1,000-ton cylindrical steel tank, one of many located west of the No 4 reactor, Asahi Shimbun said. Part of the water is within a concrete barrier surrounding a cluster of 26 tanks.
The tanks hold radioactive water generated from cooling the wrecked reactors. The water has a concentration of 80 million becquerels per liter, which translates into 24 trillion becquerels for 300 tons.—AFP/The Standard