At the same time Yucca Mountain has stalled, the cleanup at Hanford has blown through deadline after deadline, despite $19 billion over 25 years from the Department of Energy. “It’s kind of like watching glaciers move,” says Cheryl Whalen, cleanup section manager at the Washington State Department of Ecology. The radioactive waste in the tanks was supposed to have been “vitrified” into glass logs for permanent storage in 1998. The vitrification facility at Hanford is still under construction, and vitrification has been pushed back to 2032. With no Yucca Mountain, that vitrified waste still has no permanent place to go. But maybe everything will be sorted out by 2032? You can always hope?
Meanwhile, engineers at Hanford have to deal with underground tank trouble. Hanford has a 149 single shell tanks as well as 28 newer double shell tanks. “When the single shell tanks were built,” says Whalen, “they didn’t necessarily think about what to do with the liquid.” Fearing leaks, the Department of Energy eventually moved the liquid waste from single shell tanks into million-gallon double shell tanks, which were built in the 1970s to have an extra layer of protection.
That did not do the trick. The radioactive waste in single shell tanks was a sludge-like mix of metals and water; when the liquid waste went into double shell tanks, the remaining sludge just became thicker sludge. Over time, more liquid settled out and leaked. One single shell tank, the T-111, is still actively leaking low-level waste into the ground at Hanford.
But potentially more dangerous is the high-level radioactive waste in some double shell tanks at Hanford. The waste gives off so much radiation, it’s actually hot to the touch. In this most recent incident, high-level waste—a stew of plutonium, uranium and many other metals—leaked from the inner shell of the double shell tank AY-102. Back in 2012, a Hanford worker had discovered small leaks in AY-102, and workers were in the middle of pumping the waste into another intact double shell tank when they discovered the latest leak. The pumping may have disturbed solids that plugged up the old leaks, causing thousands of gallons to flood into the space between the inner and outer shells. Thankfully, the waste does not appear to have seeped into the ground around the tank.