As Japanese workers pumped out contaminated water into the Pacific Ocean from the quake- hit Fukushima nuclear facility, authorities today said radioactive iodine several million times the legal limit was detected in seawater near the plant but insisted that it posed no major health risk.
The plant's operator, Tokyo Electric Power Company (TEPCO), which last week said that contaminated water was leaking from a cracked concrete pit near the No.2 reactor, found that radiation level in seawater samples was 7.5 million times the maximum allowable limit.
The utility firm said the samples taken near the water intake of the No.2 reactor on Saturday last contained 300,000 becquerels of iodine 131 per cubic cm, or 7.5 million times the legal limit.
It said the figure had dropped to 200,000 becquerels per cubic cm, or 5 million times the legal limit, in samples taken yesterday, national broadcaster NHK reported.
The samples taken yesterday also contained 1.1 million times the legal limit of cesium 137, more than three weeks after the monster magnitude-9 quake and tsunami hit Japan's northeast leaving nearly 30,000 people dead or missing.
Japan's Nuclear and Industrial Safety Agency said it believes the radioactive substances are from nuclear fuel which leaked from the reactor into the water and flowed out.
A total of 60,000 tonnes of radioactive water is believed to be flooding the basement of reactor buildings and underground trenches connected to them at the crisis-hit Fukushima plant, authorities said.
TEPCO yesterday began dumping low-level radioactive water as an emergency step to secure room for storage of more highly contaminated water. It aims to pump out a total of 11,500 tonnes of low-level tainted water by this weekend.
An estimated 3,430 tonnes of such low radioactive water had so far been discharged into the Pacific Ocean from the plant on the coast, TEPCO was quoted as saying by Kyodo.
Industry Minister Banri Kaieda contended that contamination of the sea would pose no major health risk, but apologised for raising concerns among the public, especially fishermen.
The Nuclear and Industrial Safety Agency said the 60,000 tonnes of water -- 20,000 tonnes each from the Nos. 1-3 reactor buildings and trenches -- would be stored in tanks at the units, a facility for nuclear waste disposal at the site, an artificial floating island called a "megafloat", US Navy barges and provisional tanks.
TEPCO was also trying to stop the leakage into the sea of highly radioactive water believed to be originating from the No.2 reactor's core, where fuel rods have partially melted.
The water containing radioactive iodine-131 more than 10,000 times the legal concentration limit has been leaking from a cracked seaside pit connected to the No. 2 reactor turbine building.
