Hanford is the nation’s largest nuclear cleanup site, with 56 million gallons of radioactive waste sitting in old, leaky underground tanks just a few hours upriver from Portland. After more than 20 years and $19 billion dollars, not a drop of waste has been treated.

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Hanford sits next to the Columbia River. It was one of the original Manhattan Project sites. Its nine nuclear reactors irradiated uranium fuel rods. That created plutonium, which was extracted with chemicals, processed and shipped to weapons factories. Each step produced radioactive waste.

The cleanup plan calls for the stored waste to be removed from the underground tanks and processed into glass logs.

But the plan has problems. Radioactive wastes can generate hydrogen and other gases that can build up. If ignited, they could explode inside tanks or treatment facilities. Some of the waste contains plutonium. It’s heavy and if it clumps together it could start an uncontrollable chain reaction.
The stored waste has to be treated in special rooms called black cells, which are too radioactive for humans to enter. The machinery in these black cells is supposed to operate for 40 years with no direct human intervention. If something goes wrong, the cells could be damaged.
Construction on the treatment plant was supposed to be completed in 2007. That slipped to 2011, then 2019. And now the deadline has been extended to 2036 for the most dangerous waste.

Written, animated, edited and produced by MacGregor Campbell of OPB. Based on research by Robert McClure of InvestigateWest.