October 23, 1998

Energy Department gets ready for huge cleanup

IDAHO FALLS, Idaho (AP) - The U.S. Energy Department has unveiled its multimillion-dollar program to clean up contaminated soil and water at an Idaho National Engineering and Environmental Laboratory plant.

The Idaho Chemical Processing Plant project will mean digging up 82,000 cubic yards of soil contaminated with radioactive elements and heavy metals there and placing it in a landfill.

The agency also will try to slow the movement of radioactive iodine through the Snake River aquifer by reducing the amount of water flowing into the ground.

The entire effort may take more than 30 years and cost $175.5 million, according to agency estimates. Under federal Superfund law, the state and the U.S. Environmental Protection Agency will monitor the work. Currently, the plant is used only for storing spent fuel and solidifying liquid high-level waste.

The site became contaminated during 40 years of handling spent fuel. From 1952 to 1992, scientists used acids to recover uranium from the material.

Some of the liquid waste has been converted into a dry, more stable form, but there still are more a million gallons stored in stainless steel tanks. While none of the tanks have leaked, some of the connecting pipes have, polluting the soil.

Workers also injected radioactive waste into a well and the groundwater. That stopped in 1982, but now a plume of water contaminated with radioactive iodine stretches underground from the plant for about a mile, said Kathleen Hain, who oversees plant cleanup efforts.

The iodine is essentially radioactive forever and there is no way to stop it from moving off the site, Hain said. It will take thousands of years for the iodine to escape INEEL boundaries, and by then it should be diluted to a point where it will not pose a health risk, she said.

But current water management could mean the plume is unsafe when it moves off-site, Hain said. Water from a clay-lined pond used to evaporate runoff and cleaning materials seeps into the ground and is causing the plume to move faster, she said.

The plan calls for removing the pond and its contaminated clay bottom and landfilling it in the same spot, she said. But it will be almost two years before any of this happens.

The public will have two months to comment on the draft cleanup plan, after which the state and federal government create a final version that should be out in March.

"There will definitely be an enforceable schedule," said Dean Nygard, with Idaho's Division of Environmental Quality. After the final plan is released, work has to begin within 15 months, he said.