Washington River Protection Solutions has begun operating an exhauster to evaporate liquid from Tank T-111, the Hanford Site single-shell tank that is leaking waste into the soil beneath it. “The exhauster is performing as we hoped it would,” said Mark Lindholm, WRPS acting manager, in a statement. “This is an important step in the right direction as we try to minimize liquid inside T-111.” A 30-day test of the exhauster removed 1,000 gallons of liquid, and another 1,000 gallons have been removed since Sept. 28. WRPS says 25 to 30 gallons of liquid are being evaporated per day. “By removing the free liquid you are reducing the amount of liquid that could leak from the tank,” said Jeff Lyon of the Washington state Department of Ecology. It also reduces the pressure on the liquid waste, which could slow the rate at which it leaks.
The Department of Energy announced in late 2013 that Tank T-111 appeared to be leaking based on measurements of waste within the tank. It is the first single-shell tank believed to be leaking since workers completed removing pumpable liquids from all single-shell tanks at the former plutonium production facility. A 2014 report for DOE concluded that Tank T-111 was leaking at the rate of about 1.8 gallons per day, a decrease from 3.1 gallons per day in June 2013. The tank holds 436,000 gallons of sludge waste and has about 38,000 gallons of liquid throughout the sludge or pooled on top of the waste.
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