Tainted water at nuke plant is a concern

TOKYO - Japan's crippled nuclear power plant is struggling to find space to store tens of thousands of tons of highly contaminated water used to cool the broken reactors, the manager of the water-treatment team said.

About 200,000 tons of radioactive water - enough to fill more than 50 Olympic-size swimming pools - are being stored in hundreds of gigantic tanks built around the Fukushima Dai-ichi plant. Operator Tokyo Electric Power Co. has already chopped down trees to make room for more tanks and predicts the volume of water will more than triple within three years.

"It's a pressing issue because our land is limited and we would eventually run out of storage space," the water-treatment manager, Yuichi Okamura, told the Associated Press this week in an exclusive interview.

Tokyo Electric is close to running a new treatment system that could make the water safe enough to release into the ocean. But in the meantime, its tanks are filling up - mostly because leaks in reactor facilities are allowing groundwater to pour in.

Outside experts worry that if contaminated water is released, there will be lasting impact on the environment. And they fear that, because of the reactor leaks and water flows from one part of the plant to another, that may already be happening.

Nuclear engineer and college lecturer Masashi Goto said the contaminated-water buildup posed a long-term health and environmental threat. He worries that the radioactive water in the basements may already be getting into the underground water system, where it could reach far beyond the plant, possibly the ocean or public water supplies.

"You never know where it's leaking out, and once it's out, you can never put it back in place," he said. "It's just outrageous and shows how big a disaster the accident is."

The concerns are less severe than the nightmare scenario Tokyo Electric faced in the weeks after the March 11, 2011, earthquake and tsunami knocked out power and cooling systems at the plant, leading to explosions and meltdowns of three reactor cores in the world's worst nuclear disaster since Chernobyl. The plant released radiation into the surrounding air, soil, and ocean and displaced more than 100,000 residents who are uncertain when - or if - they will be able to return to their homes.

Dumping massive amounts of water into the melting reactors was the only way to avoid an even bigger catastrophe.

Okamura remembers frantically trying to find a way to get water to spent fuel pools located on the highest floor of the 50-meter-high reactor buildings. Without water, the spent fuel likely would have overheated and melted, sending radioactive smoke for miles and affecting possibly millions of people.

"The water would keep evaporating, and the pools would have dried up if we had left them alone," he said. "That would have been the end of it."

Goto, the nuclear engineer, believes it will take far longer than the utility's goal of two years to repair all the holes in the reactors. The plant also would have to deal with contaminated water until all the melted fuel and other debris is removed from the reactor - a process that will easily take more than a decade.

"The longer it takes," he said, "the more contaminated water they get."