TOKYO ? Japan?s government announced on Tuesday its first radiation safety standards for fish, hours after the operator of a crippled nuclear power plant said that seawater collected near the facility contained radiation several million times the legal limit.
The new standards were announced after a type of fish was caught last Friday off the coast of Ibaraki Prefecture, halfway between the Fukushima Daiichi Nuclear Power Station and Tokyo, that contained high levels of radioactive iodine 131. The small fish contained 4,080 becquerels per kilogram ? about 2 pounds ? of iodine 131. The new standard allows up to 2,000 becquerels per kilogram of iodine 131, the same standard used for vegetables in Japan.
The announced standards for fish came hours after the Tokyo Electric Power Company said it found radioactive iodine 131 in seawater samples collected to be 200,000 becquerels per cubic centimeter, or five million times the legal limit. The samples were collected Monday near the water intake of the No. 2 reactor of the Daiichi plant.
The sample also showed levels of cesium 137 to be 1.1 million times the legal limit, according to the public broadcaster NHK. Cesium remains in the environment for centuries, losing half its strength every 30 years.
The Monday sampling of seawater was collected before Tokyo Electric began dumping more than 11,000 tons of low-level radioactive water. The Monday sample showed a drop of radioactive iodine levels since Saturday, when Tokyo Electric said samples of iodine 131 were at 300,000 becquerels per cubic centimeter.
Analysts have said radiation dissipates quickly in the ocean, and in a report by NHK, Tokyo Electric said the latest samples were collected closer to the Daiichi plant than before and did not reveal a higher level of contamination.
Meanwhile, the death toll from the March 11 9.0-magnitude earthquake and tsunami rose to 12,341 on Tuesday, the country?s National Police Agency said. More than 15,000 people remain missing, and more than 160,000 are staying in temporary shelters across the country, the agency said.
The crisis at the power station, now in its fourth week, has shaken public confidence in Tokyo Electric Power, the operator of the Daiichi plant. Share prices for the utility plunged to an all-time low on Tuesday over concern by investors of the financial burden of the work being carried out at Daiichi.
A government panel on Tuesday suspended work revising the country?s policy platform on nuclear power, according to local news media reports, saying the crisis needed to be resolved before Japan could publicly assess its nuclear power policies. ?We have to admit that there has been an error in the criteria of judgment in promoting the country?s nuclear power policy,? Shunsuke Kondo, chairman of the Japan Atomic Energy Commission, said in a report by the Kyodo news service.
Most of the low-level radioactive water being dumped from the Daiichi plant is to be released by Tuesday evening, mostly to make room in storage containers for increasing amounts of far more contaminated runoff. The water being released contains about 100 times the legal limit of radiation, Tokyo Electric said. The more contaminated water has about 10,000 times the legal limit.
The effort would help workers clearing radioactive water from the turbine buildings at the damaged reactors, making it less dangerous to reach some of the most crucial controls for their cooling systems, which were knocked out by the quake and tsunami. The hopes are that the cooling systems can be revived and bring the plant back under control.
The pumping effort is not expected to halt or alter a leak from a large crack in a six-foot-deep concrete pit next to the seawater intake pipes near the No. 2 reactor. The leak has been spewing an estimated seven tons of highly radioactive water an hour directly into the ocean.
Tokyo Electric has been pumping hundreds of tons of water into four of the plant?s six reactors to cool nuclear fuel in the cores of three of them and in spent fuel storage pools at four.
But leaks whose source is unclear have flooded areas of the plant, complicating in the effort to stave off full meltdowns of the fuel. Workers have been pumping the runoff into storage tanks, most urgently the highly radioactive water flooding the turbine building of the No. 2 reactor. But the storage system is now full, and adding capacity will take time.
The country?s trade and industry minister, Banri Kaieda, said on Tuesday that 60,000 tons of radioactive water is thought to be flooding the basement of the plant?s reactor buildings and underground tunnels, according to a Kyodo report.
Tokyo Electric is rushing tanks to the plant, though they may not arrive until mid-April, a company spokesman said. The company also plans to moor a giant barge off the coast to store contaminated water, though getting the barge in place will take at least a week, he said.
Japan has asked Russia?s state-controlled nuclear agency, Rosatom, to send a radioactive waste disposal facility to help dispose of the contaminated water. Rosatom spokesman Sergei Novikov said talks were being held to send the floating facility to Japan, according to RIA Novosti news service.
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