By Seattle Times staff and The Associated Press
Six single-shell underground radioactive waste tanks at the nation’s most contaminated nuclear site are leaking, Gov. Jay Inslee said Friday.
He warned there could be more leaky tanks and that an investigation is under way to find out. There is no immediate safety threat, he said.
Inslee made the announcement after meeting with federal officials in Washington, D.C. Last week it was revealed that one of the 177 tanks at south-central Washington’s Hanford Nuclear Reservation was leaking liquids.
“The amount of leakage varies from tank to tank. They are certainly levels that cause us concern and demand action,” Inlsee said in a conference call with reporters on Friday.
Inslee is in D.C. this weekend for a meeting with Energy Secretary Steven Chu and a meeting with other governors at the White House.
The governor said it was discovered that readings from the tanks were not being properly evaluated. “He (Chu) reported to me that a new evaluation of data … has shown that there are six tanks that have had a drop in level with a high probability that these tanks are leaking,” Inslee said.
“So to find these, you do have to have pretty exquisite instruments to find the change in the level. We have those instruments. They work and have worked. The problem, according to Secretary Chu, is the data simply was not interpreted in a way that would be able to identify the change in level.
“If you can imagine a graph with a generally rising curve, as the graph goes up over time with jagged peaks, up and down daily … and if you look at it across the spectrum of the horizontal axis you’ll see a rise in the graph. But if you only look at it for a tiny sliver of that spectrum, you’ll only see tiny little changes that are not interpreted as leakage.”
Officials are now checking the readings from other tanks to make sure they’ve been interpreted properly.
“This raises the prospect that we have leakage in additional tanks even above and beyond the six,” Inslee said.
The governor said he was assured “there is no imminent public health threat. If this material were to reach ground water, it would be quite some period of time, perhaps years,” he said.
Still Inslee said, “We are going to be insistent on the fastest technological solution to eliminate this risk of leaking.”
The tanks, which already 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.
The U.S. Department of Energy said earlier that liquid levels were decreasing in one of the tanks at the site. Monitoring wells near the tank have not detected higher radiation levels.
The federal government created Hanford in the 1940s as part of the top-secret Manhattan Project to build the atomic bomb. The government spends $2 billion each year on Hanford cleanup — one-third of its entire budget for nuclear cleanup nationally. The cleanup is expected to last decades.
Central to cleanup is the construction of a plant to convert millions of gallons of waste into glasslike logs for safe, secure storage. The $12.3 billion plant is billions of dollars over budget and behind schedule.
Inslee and Oregon Gov. John Kitzhaber have championed building additional tanks to ensure safe storage of the waste until the plant is completed. Democratic Sen. Ron Wyden of Oregon said earlier this week that he shares their concerns about the integrity of the tanks, but that he wants more scientific information to determine it’s the correct way to spend scarce money.
Wyden noted the nation’s most contaminated nuclear site — and the challenges associated with ridding it of its toxic legacy — will be a subject of upcoming hearings and a higher priority in Washington, D.C.