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Nation

Leak complicates nuclear site cleanup

OLYMPIA, Wash. — The long-delayed cleanup of the nation’s most contaminated nuclear site became the subject of more bad news Friday, when Governor Jay Inslee Washington announced that a radioactive waste tank there is leaking.

The news raises concerns about the integrity of similar tanks at south-central Washington’s Hanford nuclear reservation and puts added pressure on the federal government to resolve construction problems with the plant being built to alleviate environmental and safety risks from the waste.

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The tanks, which are long past their intended 20-year life span, hold millions of gallons of a highly radioactive stew left from decades of plutonium production for nuclear weapons.

On Friday, the US Department of Energy said liquid levels are decreasing in one of 177 underground tanks at the site. Monitoring wells near the tank have not detected higher radiation levels, but Inslee said the leak could be in the range of 150 gallons to 300 gallons over the course of a year and poses a potential long-term threat to groundwater and rivers.

At the height of World War II, the federal government created Hanford as part of a project to build the atomic bomb. The site produced plutonium for one of two atomic bombs dropped on Japan, effectively ending the war. Plutonium production continued there through the Cold War.

Today, Hanford is the nation’s most contaminated nuclear site. Cleanup will cost billions of dollars and last decades.

Central to that cleanup is the removal of millions of gallons of a highly toxic, radioactive stew — enough to fill dozens of Olympic-size swimming pools — from 177 aging, underground tanks. Many of those tanks have leaked over time — an estimated 1 million gallons of waste — threatening the groundwater and the neighboring Columbia River, the largest waterway in the Pacific Northwest.

Twenty- eight of those tanks have double walls, allowing the Energy Department to pump waste from leaking single-shell tanks into them. However, there is very little space left in those double-shell tanks today.

In addition, construction of a $12.3 billion plant to convert the waste to a safe, stable form is years behind schedule and billions of dollars over budget. Technical problems have slowed the project, and several workers have filed lawsuits in recent months, claiming they were retaliated against for raising concerns about the plant’s design and safety.

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