Radioactive Water Leaks at Japanese Nuke Site

The Associated Press is reporting that 45 tons of radioactive water appear to have leaked at the stricken Fukushima nuclear power plant site over the weekend. The leak amounts to about 11,000 gallons of highly contaminated water which was being concentrated and purified. At least 300 liters (79 gallons) may have reached the ocean. The water is believed to be contaminated with radioactive isotopes of cesium, iodine and possibly strontium.

Massive amounts of water contaminated with various radioactive isotopes have accumulated at the Japanese plant site. Both fresh water and sea water were used in emergency cooling operations shortly after the plant was disabled by the March 11 earthquake and tsunami. The meltdown of three of the six reactors on site and the damage to the existing cooling systems necessitated the use of fire engines and other pumps to spray the buildings and their interiors. Four of the reactor buildings also experienced hydrogen explosions resulting in partial or total damage to roofs and walls that had kept rain and snow out.

The owner of the Fukushima nuclear power plant, TEPCO, has been struggling with the large amounts of contaminated water that must be stored on site. Much of the water remains in the damaged buildings. The most current report from Japan's Nuclear and Industrial Safety Agency shows around three feet of standing water in nearly all affected structures. TEPCO's most recent report on radioactive water storage and treatment states that nearly 48 million gallons of water has been at least partially treated to date. Another 23.6 million gallons of water remain in storage awaiting treatment.

This is the latest in a series of leaks from the damaged Fukushima plant. Nuclear Engineering International lists three other radioactive water leaks. TEPCO intentionally released thousands of tons of water with low level contamination into the sea in April. Ventilation systems have also discharged airborne radioactive contaminants.

TEPCO continues to struggle with cooling the three reactors that melted down. Recent sensor readings suggest that fission may be continuing to occur in at least one of the melted pools of uranium. Cooling efforts combined with cleanup and decontamination efforts will continue to generate radioactively contaminated water for some time. TEPCO hopes to have all three active reactors in cold shutdown by year end.