The Philippine Online Chronicles

The Japanese government has allowed the Fukushima Dai-ichi Nuclear Power Station operator Tokyo Electric Power Company (TEPCO) to release 11,500 tons of radioactive wastewater into the Pacific Ocean.

TEPCO has been pumping sea water into the power station to help cool the nuclear reactors after the damage done to the power station’s cooling systems by last month’s magnitude-9 earthquake. Although much of the water evaporates, a significant amount has begun flooding the turbine buildings of Reactors units 2, 5 and 6 and is now threatening to swamp the generators powering the remaining active cooling systems.

A facility at the plant designed to store and treat the radioactive water has already been filled with runoff, prompting the operator to dump less seriously contaminated water into the ocean.

“This is in order to have sufficient capacity to store highly contaminated water found in the basement of the unit 2 turbine building," said the International Atomic Energy Agency (IAEA)in a statement.

“We have no choice but to release water tainted with radioactive materials into the ocean as a safety measure,” added Japan’s Chief Cabinet Secretary Yukio Edano in a televised press conference.

“Unfortunately, the water contains a certain amount of radiation,” he said. “This is an unavoidable measure to prevent even higher amounts of radiation from reaching the sea.”

The water that will be released—the equivalent of more than four Olympic swimming pools—contains about 100 times legal limits of radiation, but will not pose a threat to human or marine life, said TEPCO.

“TEPCO has estimated that the potential additional annual dose to a member of the public would be approximately 0.6 millisieverts (mSv), if they ate seaweed and seafood caught, from near the plant, every day for a year," said the IAEA.

Bloomberg says that that is still less than the 0.85 millsievert from a year of exposure to granite that comprises the U.S. Capitol, according to the U.S. Army Corps of Engineers.

Radioactive water leak

TEPCO has also reported a leak from the unit 2 turbine building, through which water contaminated with high amounts of radioactive iodine has been flowing into the sea.

Initial attempts to staunch the leak by pouring cement and polymer around the area has been unsuccessful. Workers have also tried plugging the leak with sawdust and garbage bags filled with shredded newspapers.

Workers will continue trying to stem the leak, said Hidehiko Nishiyama, deputy director general of the Nuclear and Industrial Safety Agency. Japanese engineers also plan to build two giant "silt curtains" made of polyester fabric in the sea to block the spread of more contamination from the plant.

Japan has asked for the aid of Russia to contain the leakage by sending the "Suzuran," a floating radiation treatment plant used to decommission Russian nuclear submarines in nearby Vladivostock.

The Suzuran is one of the world’s largest liquid radioactive waste treatment plants, treating radioactive liquid with chemicals and storing it in cement form. It can process up to 35 cubic metres of liquid waste a day.