Radiation levels in the sea near what is left of the Japanese nuclear power plant Fukushima-1'''', is still high, but since the accident has been more than six months. The highest point (100 thousand Bq / m) pollution reached in early April. It was expected that most of the radioactive iodine, cesium and plutonium quickly disperse to the Pacific Ocean.
However, this did not happen. Probably the reason is that the contaminated water is still flowing into the sea from the nuclear plant, and can, twist current radioactive material in one place. More likely is that both factors work together.
According to official estimates the Japanese government and plant operator TEPCO, from March 11 to the end of May fell into the ocean 3500 TBq of cesium-137. Pollution has increased in April due to the fact that a) is not able to immediately find the leak, b) TEPCO decided to dump contaminated water into the ocean. The following 10 thousand TBq cesium apparently were in the sea with the water condensed from the steam. Last week, TEPCO admitted that so far every day flows away from the station into the sea up to 500 tons of contaminated water. This, however, is too small to explain this slow decline radiation.
By the way, last week, the Japanese government announced its intention to introduce a new standard that will be determined by the need for decontamination of soil: Now, according to the revised regulations, the proposed decontamination zone will include not only the major population centers in Fukushima Prefecture, where the plant is located emergency, and areas in neighboring prefectures, according to RIA Novosti.
According to a preliminary estimate made last month, the area in which it will be necessary to decontaminate the soil in five Japanese prefectures will be 2.419 thousand square meters, which is 17% of the area of Fukushima Prefecture.
Now, according to the new standards, this list may add areas that are also affected by the accident at the plant Tochigi and Gunma prefectures. The cost of this will amount to 370 billion yen (4.8 billion dollars). Then the material will be placed in temporary storage. Only the study and design of structures and equipment for storage is expected to spend 2 billion yen (26.14 million dollars).
On the disposal of radioactive waste will have to spend 78 billion yen (100 million dollars). All in the budget for the next year the ministry is planning to include the costs of decontamination, the amount of 450 billion yen (5.88 billion dollars).