Science behind Hanford treatment tanks questioned

RICHLAND, Wash. - A federal nuclear watchdog agency is questioning some of the science behind a massive treatment plant at the Hanford Nuclear Reservation in southeast Washington. In a letter released Thursday, federal examiners say key treatment tanks could pose risks.

The Department of Energy is building a huge plant in the middle of the sagebrush-dotted desert to bind-up millions of gallons of radioactive sludge in glass. But before Hanford managers do that, they have to treat the sludge several times in large tanks.

The Defense Nuclear Facilities Safety Board says some of the science modeling behind the design of those tanks is faulty and shouldn't be relied on. It's known as the Low Order Accumulation Model.

But, Carrie Myer with the Department of Energy says the modeling is only one piece of the design. And she says her agency is working on these concerns.

"Until those questions have been answered," Myer said, "we will not make any decisions or conclusions regarding the use of the Low Order Accumulation Model."

The Defense Nuclear Facilities Safety Board says it wants large-scale tests to prove that the treatment tanks won't explode or release flammable gas.

On the Web:

• Defense Nuclear Facilities Safety Board letter.
• Hanford Waste Treatment & Immobilization Plant Project.

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