Sunday, September 16, 2007

Hanford Nuclear Accident

Subject: hanford nuclear accident

Hanford accident is a wake-up call


The Hanford nuclear waste site had its worst accident in years on July 27. A pipe burst and sprayed the air and ground with some of the
hottest material to be found on the site.

The accident happened at an old single-shell tank that dates back to the early 1950s. It holds highly radioactive sludge left over from producing the nation's first nuclear weapons. A contractor, CH2M Hill, was transferring the waste from the failing old tank to a new one.

Put your finger on the end of a straw and suck the other end. What happens to the straw? That appears to be what happened out on the Hanford tank farm

Besides cesium, strontium, americium, plutonium and a toxic soup of non-radiological hazardous chemicals, the peanut butter-thick sludge is chunked up with salt cake and other glop. Engineers try to stir this up, and thin it with a bit of water. They have designed all kinds of redundancies to prevent disasters in the line carrying the sludge from one tank to another. Less thought went into the pipe carrying in clean water. After all, the water should flow into the tank, not out.

Unless the pump clogs up. And somebody reverses the pump to clear it. And it doesn't work, so they do it again. Do you see that straw collapsing? Or maybe the suction finally works, and a hundred gallons of deadly brew pours out into the vacuum, escaping its half-century prison, bursting from the weakened line, and spilling onto the ground and into the air.

Did CH2M Hill know that it had a problem on its hands? It seems an increase in radiation levels registered right after the pump was run at about 2 a.m. A team was not sent to investigate until about eight hours later. What the team found was deemed serious enough to order Hanford
workers to take cover.

That event raises many red flags. Why did the engineering mistakes occur? Was it a case of too much pressure to produce results, without enough planning and oversight? Were the investigators properly protected? Could an earlier investigation have stopped workers from
coming onto the site in the first place, instead of giving them a belated order to take cover? Why did it take so long to make an official discovery of the accident?

Oregon Sen. Ron Wyden, for one, has asked the Defense Nuclear Facilities Safety Board to become involved. There are 149 old single-shell tanks at Hanford, and Wyden calls the commitment to getting the waste out "tenuous."

The federal government has poured billions into building a plant to treat the waste. But the plant is additional billions over budget, years behind schedule and technologically novel and uncertain. There aren't enough double shell tanks to receive the old waste; July's pipe accident is not the first problem encountered trying to pump material from one tank to another.

This is a good time to ask questions because the U.S. Department of Energy is putting together a new contract for managing the high-level radiation waste tanks at Hanford. For CH2M Hill, it is not such a good time for accidents to happen. That's why Wyden called for a truly independent investigation, "not just of the most recent release and its underlying causes, but to also examine the operational assumptions, plans, schedule and engineering approach used in the tank waste
transfer program."

Right now, Wyden stands alone. Who in Washington will join his call to get to the bottom of what happened at Tank S-102? Let's seek some fresh, disinterested opinions, before we see more inadvertent experiments in elementary physics.

Helen Wheatley is Heart of America Northwest's board president.

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