New Washington Gov. Jay Inslee wants more waste tanks built at Hanford to keep environmental cleanup on schedule, his staff said Thursday.
The Hanford Advisory Board and Oregon Gov. John Kitzhaber already have told the Department of Energy that more double-shell tanks must be built.
Their concern comes after a leak was confirmed in October in the inner shell of Hanford's oldest double-shell tank, which already has been used for the 40 years for which it was designed.
Hanford's 28 double-shell tanks are needed to hold radioactive waste emptied from 149 leak-prone single-shell tanks until 56 million gallons of waste can be treated for disposal. That could take another 40 years.
A court-enforced consent decree sets requirements for emptying 21 single-shell tanks through 2022, and state officials believe they could be at risk because of lack of double-shell tank space.
"We expect DOE to make good on its consent decree," said David Postman, Inslee's spokesman.
Delays in building the vitrification plant, which will treat the tank waste for disposal, could delay waste retrieval from single-shell tanks without more storage space, said Cheryl Whalen, cleanup section manager for the Washington State Department of Ecology.
As tank waste is fed to the plant, more space will be available in double-shell tanks for single-shell tank waste. But DOE officials have said that they may not be able to have the vitrification plant operating as scheduled in 2019 because of technical issues.
There also are new concerns about how much waste each existing double-shell tank may hold safely.
State Department of Ecology officials briefed Inslee late Wednesday, shortly after Kitzhaber's letter to DOE calling for more double-shell tank space became public.
Both Inslee and Kitzhaber said money must be found to add more tank space without taking funds from other Hanford environmental cleanup work. Hanford is massively contaminated from the past production of plutonium during World War II and the Cold War for the nation's nuclear weapons program.
Rep. Doc Hastings, R-Wash., told the Herald editorial board Thursday that it is premature to call for additional tanks without knowing more about the new schedule and cost estimates for the vitrification plant.
He is concerned that shifting the focus to more tanks could be used as an excuse to further stall starting up the plant. Building more tanks would be a huge undertaking, he said.
"We made the decision to empty the tanks, vitrify the waste and send it to Yucca Mountain," a planned national repository, Hastings said. "We should stick to that course."
DOE, which did not comment on Inslee's recommendation, has said that building one double-shell tank could cost $100 million, and building a group of six tanks could take five to seven years.
The consent decree, which was signed by a federal judge a little more than two years ago, requires DOE to have all 16 tanks in a group called the C Tank Farm emptied by fall 2014. Then it must start emptying five more tanks by 2017 and have that work finished by 2022, about the time the vitrification plant is supposed to be in full operation.
However, there are concerns about whether DOE can even finish retrieving waste from all the C Farm tanks because it may not be able to put as much retrieved waste in double-shell tanks as planned, Whalen said.
Questions have been raised about whether flammable gas may be generated deep within sludge being held in radioactive waste.
Washington River Protection Solutions has been evaluating tanks one by one, but unless tanks are cleared the amount of waste they can hold is limited. For the double-shell tank now used to hold waste emptied from Tank C-101, the limit is 170 inches of sludge until more is known.
After the leak within the first double-shell tank was discovered, an integrated project team was formed to consider how to address that leak, which is confined between the shells of the tank, and any deterioration of other tanks.
The team includes DOE, Washington River Protection Solutions and the Washington State Departments of Ecology and Health, with the state of Oregon recently joining.
"We're talking about tank space issues," Whalen said. "We have to investigate how much space we should be considering."
Washington River Protection Solutions has finished inspections of two more double-shell tanks since the leak in Tank AY-102 was discovered. It announced Thursday that Tank AZ-101 had no evidence of a leak. Earlier it had concluded that Tank AY-101, the second tank built, also had no evidence of a leak.
The inspection of the next double-shell tank should be completed this month.