The Department of Energy is considering whether Hanford's vitrification plant could start treating some waste three years ahead of current schedules.
The plant is required to begin turning radioactive waste into a stable glass form for disposal in late 2019. But there might be an opportunity for a phased start of waste treatment in late 2016, said Dale Knutson, DOE project director for the $12.2 billion plant.
The proposed 2016 start would be for treatment of only the low-activity radioactive waste and not high-level radioactive waste. It also could include operating the Analytical Laboratory, but not the Pretreatment Facility, which will separate waste into low-activity and high-level waste streams.
It's not the first time that moving up the schedule for operating the Low Activity Waste Facility has been proposed.
"It's different this time," Knutson said.
Earlier proposals would have required investments in large supporting infrastructures, such as the capacity to pretreat large amounts of waste, he said.
The new proposal would rely on new technologies that would separate out modest quantities of low-activity waste before it was piped to the vit plant. The separation would be done in or at the underground tanks where radioactive waste is stored.
DOE should know in six months if new technology to separate out low-activity waste will work.
It's evaluating technology called rotary microfiltration that would produce waste with uniform particle size and cull out large particles that include high-level radioactive waste. Then the waste would be treated with an ion exchange process to remove radioactive cesium to make the waste easier to handle. If the cesium remains, workers have to use remotely operated equipment to protect themselves from radiation.
Waste remaining in each tank still would need to be sent to the Pretreatment Facility when it begins operating to separate out more low-activity waste from high-level waste.
"I think it's a very doable plan," Knutson said. "It gives us a sense of urgency."
Since DOE Deputy Secretary Daniel Poneman picked Knutson as federal project director for the vit plant last May, his charge has been not to construct a plant but to make glass, he said.
Starting to do that in 2016 would have several advantages, he said.
In late 2016, DOE expects to complete cold commissioning of the building for treating low-activity waste. That would include starting up and operating the plant, just not with radioactive waste.
If DOE then waits to start processing waste until 2019, the melters would be turned off. Each time the glass melters are turned off and cooled down, their operating life is reduced.
"Once you get them thermally hot, they like to stay that way," Knutson said.
There also are advantages to testing the start-up and commissioning process with radioactive waste at the low-activity facility years before the hot commissioning of the Pretreatment Facility and High-Level Waste Facility.
"We're going to learn in a lower-hazard environment," Knutson said.
The 2016 start would give DOE three years of operating experience before the High Level Waste Facility began operating. It would allow training and qualification of the work force and validation of procedures, he said.
The Low Activity Waste Facility would not be operating at full capacity during the early start phase. Instead, it would produce about one canister of glassified waste daily. Eventually, about 11,000 to 15,000 canisters of low-activity glass are expected to be produced.
"You can get a start on the 53 million gallons of waste out there," Knutson said.
The plan makes sense to the Washington State Department of Ecology, said Suzanne Dahl, the agency's tank treatment section manager. The state is the project regulator.
"From our perspective, it has a lot of merit," she said. The state is prepared to shift work around to move the project through the permit process, she said.
Not only would the proposal get operators trained early, it also could help identify problems early and prevent work from stacking up late in the process of starting to treat waste, she said.
DOE already expects to have the Low Activity Waste Facility, the Analytical Laboratory and about 20 smaller support facilities on the vit plant campus constructed in 2014.
The first of the support buildings, the switchgear building is expected to be fully operational in 2012, requiring only maintenance until the plant is ready to use it.
-- Annette Cary: 582-1533; firstname.lastname@example.org; More Hanford news at hanfordnews.com.