The operator of Japan’s tsunami-crippled nuclear power plant has said that about 300 tons of highly radioactive water have leaked from one of the hundreds of storage tanks there its worst leak yet from one of the vessels.
Tokyo Electric Power Co (Tepco) said the contaminated water leaked from a steel storage tank at the wrecked Fukushima Dai-ichi plant.
Tepco spokesman Masayuki Ono said the leaked water seeped into the ground after escaping piles of sandbags added to a concrete barrier around the tank. Workers were pumping out the puddle and the remaining water in the tank and will transfer it to other containers.
The water’s radiation level, measured about 2ft (50 cm) above the puddle, is about 100 millisieverts per hour five times the annual exposure limit for plant workers, Mr Ono said.
The plant suffered multiple meltdowns following Japan’s massive earthquake and tsunami in March 2011. Hundreds of tanks were built around the plant to store massive amounts of contaminated water coming from the three melted reactors, as well as underground water running into reactor and turbine basements.
Four other tanks of the same design had similar leaks since last year. Mr Ono said the latest leak was the worst.
The massive amount of radioactive water is among the most pressing issues affecting the clean-up process, which is expected to take decades.