Levels of radioactive materials soaring in sea near nuke plant

Kyodo News, TOKYO, March 26, Kyodo

Levels of radioactive materials are skyrocketing in the sea near the crisis-hit nuclear power station in Fukushima Prefecture, the government's nuclear safety agency said Saturday, while the plant's operator has started injecting fresh water into the No. 2 reactor core to enhance cooling efficiency.

According to the government's Nuclear and Industrial Safety Agency, radioactive iodine-131 at a concentration 1,250.8 times the legal limit was detected Friday morning in a seawater sample taken around 330 meters south of the plant, near the drain outlets of its troubled four reactors.

The level rose to its highest so far in the survey begun this week, after staying around levels 100 times over the legal limit. It is highly likely that radioactive water in the plant has disembogued into the sea, Tokyo Electric Power Co said.

The result could fan concerns over fishery products in northeastern Japan as highly radioactive water has been found leaking near all four troubled reactor units at the plant.

Radioactive materials ''will significantly dilute'' by the time they are consumed by marine species, the agency said, adding, it will not have a significant impact on fishery products as fishing is not conducted in the area within 20 kilometers of the plant as the government has issued a directive for residents in the area to evacuate.

If people ingest 500 milliliters of water containing the same level of radioactive iodine, the radiation levels would reach the 1 millisievert limit which people can be safely exposed to in one year, the agency said.

Meanwhile, the U.S. Department of Energy said in its radiological assessment released Friday that by comparing aerial measurement data from Thursday with previous measurements, the data indicate peak exposure rates in the western side of the Fukushima plant are lower.

The utility, known as TEPCO, is currently injecting fresh water into the No. 2 reactor core to prevent crystallized salt from seawater already injected from forming a crust on the fuel rods and hampering the smooth circulation of water, thus diminishing the cooling effect. It has begun injecting fresh water into the No. 1 and No. 3 reactor cores.

At the same time, the firm is trying to remove pools of water containing highly concentrated radioactive substances that may have seeped from either the reactor cores or the spent fuel pools, while also trying to restore power at the No. 2 reactor.

On Thursday, three workers were exposed to water containing radioactive materials 10,000 times the normal level at the turbine building connected to the No. 3 reactor building. On Friday, a pool of water with similarly highly concentrated radioactive materials was found in the No. 1 reactor's turbine building, causing some restoration work to be suspended.

Similar pools of water were also found in the turbine buildings of the No. 2 and No. 4 reactors, measuring up to 1 meter and 80 centimeters deep, respectively. Those near the No. 1 and No. 3 reactors were up to 40 cm and 1.5 meters deep.

==Kyodo