TOKYO, March 26 — 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 radiation levels in seawater do not pose an immediate risk to human health, government officials said. But they are well above normal levels and 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.
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, will try to remove pools of water containing highly concentrated radioactive substances that may have seeped from either the reactor cores or spent fuel pools, while also trying to restore power at the No. 2 reactor in an effort to prevent the situation from worsening further.
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. (PNA/Kyodo) scs/rsm