UK & World News
Fukushima Toxic Leak: Hundreds Of Tanks Checked
Workers at Japan's crippled Fukushima nuclear plant have scrambled to check 300 tanks storing highly radioactive water after one sprang a leak feared to have seeped into the Pacific.
Some 300 tonnes of toxic liquid is believed to have escaped from one of the water tanks used to cool the broken reactors.
Tokyo Electric Power Co (TEPCO), which operates the plant, warned that some of it may have flowed into the ocean.
Spokesman Tsuyoshi Numajiri said: "We are hurriedly checking if some 300 tanks of the same type holding contaminated water have the same leak problem.
"We have finished pumping out water from the troubled tank, while we have continued removing the soil soaked by the water," he said.
He said traces of radioactivity were detected in a drainage stream and that "we cannot rule out the possibility that part of the contaminated water flowed into the sea".
On Wednesday, nuclear regulators said the leak represented a level-three "serious incident" on the UN's seven-point International Nuclear Event Scale (INES), which measures radiation accidents.
It is the most serious single event since the plant was declared to be in a "state of cold shutdown" - effectively indicating it was under control at the end of 2011.
The meltdowns at the plant in March 2011, triggered by the earthquake and tsunami, were a level seven on the INES scale.
The Chernobyl disaster in 1986 is the only other incident to have been given the most serious ranking.
TEPCO has said puddles of water near the tank were so toxic that anyone exposed to them would receive the same amount of radiation in an hour that a nuclear plant worker in Japan is allowed to receive in five years.
The utility did not have a water-level gauge on the 1,000-tonne tank, which experts say would have made it a lot more difficult to detect the problem.
The safety checks on 300 tanks came after Nuclear Regulation Authority (NRA) chairman Shunichi Tanaka voiced concern that there could be similar leaks from other containers.
He said: "We must carefully deal with the problem on the assumption that if one tank springs a leak the same thing can happen at other tanks."
The company - which faces huge clean-up and compensation costs - has struggled to cope with the disaster.
TEPCO in July admitted for the first time that radioactive groundwater had been leaking outside the plant. This month it started pumping it out to reduce leakage into the Pacific.