Nuclear waste tank leak at Hanford not a risk, state says

Fluctuations inside a huge tank of radioactive waste raised concerns on the Hanford Nuclear Reservation near the Tri-Cities over the weekend.

A federal contractor said the amount of nuclear waste that has been leaking between the two walls of the underground tank for several years grew dramatically.

None of the waste appears to have escaped from the tank into the environment, said the contractor, Washington River Protection Solutions.

A state agency said Monday the leak doesn’t present a public risk.

The tank is being emptied because leaks have previously been detected in the containment areas between walls. It originally held 800,000 gallons of nuclear and chemical waste from the production of materials used for nuclear weapons. About 20,000 gallons of that waste are left in tank AY-102.

On Sunday, a leak detector showed more waste was seeping into the area between the tank walls during the removal process. That work was put on hold to evaluate the leak and come up with a plan to recover the material.

So far, the material is contained in the space between the walls, the state Department of Ecology reported.

“There is no indication of waste leaking into the environment or risk to the public at this time,” department officials said in a news release.

But workers were trying Monday to determine why the waste that leaked between the tank walls rose by about 8 inches Sunday and then dropped by half an inch.

Hanford for decades made plutonium for nuclear weapons, including the atomic bomb dropped on Nagasaki, Japan. The site contains a huge volume of radioactive waste that will cost billions of dollars and take decades to clean.

Staff writer Jim Camden and the Associated Press contributed to this report.