The vitrification plant will not address all of Hanford's high-level radioactive waste, including waste that has leaked from tanks, officials told the U.S. Nuclear Waste Technical Review Board on Tuesday.
The board met in Richland and spent much of the day focused on vitrification of waste, including what to do with vitrified waste and used nuclear fuel with no national repository for high-level waste available. The board was formed in 1987 to offer technical advice on nuclear waste management to Congress and the energy secretary.
But with the focus on vitrification, other Hanford waste is at risk of slipping under the radar, said Ken Niles, representing the state of Oregon, as he and other regional officials addressed the board about Hanford concerns.
The federal Department of Energy is required to vitrify, or glassify, high-level radioactive waste now held in underground tanks from the past processing of irradiated fuel to produce plutonium for weapons.
But in the past, at least 1 million gallons of waste from those tanks has leaked or spilled into the soil, Niles said.
The state of Washington considers the leaks to be high-level radioactive waste, said Suzanne Dahl, representing the Washington State Department of Ecology.
But DOE has been fairly clear it intends to leave most of it in the soil where it is, Niles said.
DOE has indicated it may be able to remove or immobilize some of the leaked waste in the soil, but is interested in leaving mostly emptied tanks in the ground rather than digging them up. That could make addressing the contaminated soil beneath the tanks problematic.
Studies to address contaminated soil deep underground are in early stages and have been limited by budget reductions, Niles said.
At least six tanks have been newly discovered to be leaking, Niles said. Although they now are releasing relatively small amounts of radioactive waste into the ground in central Hanford, there is no assurance that will be the case in two weeks, two years or two decades, he said.
The leaking tanks "are the canary in the coal mine," said Pam Larsen, the executive director of Hanford Communities, an organization of local governments. "They need treatment as soon as possible."
Hanford also has nearly 2,000 containers of radioactive cesium and strontium that was removed from waste in Hanford's tanks in the 1970s to reduce heat in the tanks, regional speakers said.
There has been discussion of blending the waste into the high-level waste being glassified at the vitrification plant. But there's also been a proposal to store the waste until more of its radioactivity naturally decays and then allow it to be disposed in a landfill for radioactive waste, Niles said.
However, the state of Oregon believes that it should go to a national deep geological repository, when one is developed, for high-level radioactive waste, Niles said.
In addition, Hanford already has 34 logs of vitrified waste, said Allyn Boldt, representing Hanford Challenge, a Hanford watchdog group.
The waste was vitrified for studies planned in Germany in the '80s, but never left Hanford, Niles said. The vitrified logs should go to a deep geological repository, he said.
The technical review board also needs to remember that in addition to tank leaks and spills, 450 billion gallons of contaminated liquids were poured into the ground, Larsen said. As a result, contaminated groundwater is a significant problem.
The state of Washington expects DOE to make good on its commitment to transform all 56 million gallons of tank waste into a waste form that's as protective of the environment as glass, Dahl said.
Plans call for separating tank waste into low-activity and high-level radioactive waste streams for separate treatment at the vitrification plant. However, as planned now, the vitrification plant could not treat all the low-activity waste in a reasonable time.
The low-activity waste would contain most of the chemicals and 5 percent of the tank waste radioactivity. Once treated it would be disposed of at Hanford rather than sent to a deep geological repository.
DOE agreed to vitrify Hanford's low-activity waste in the '90s in exchange for delaying work on the vitrification plant, Dahl said. The state later agreed to let DOE investigate other waste forms than glass, but DOE did not prove by a 2006 deadline that any other form would be protective enough of the environment to allow drinking water standards to be met, she said.
More recently an extensive environmental study, the Hanford Tank Closure and Waste Management Environmental Impact Statement, found that grouting or steam reforming the low-activity waste would violate water standards eventually, Dahl said.
Russell Jim, representing the Yakama Nation, which has treaty rights at Hanford, said the tribe has not agreed that high-level radioactive waste can be reclassified as low-activity waste.