The Department of Energy must hold additional public hearings in the Pacific Northwest on a proposal that could lead to a limited amount of radioactive waste being grouted in place in the Hanford Site’s underground storage tanks, according to three members of Washington state’s congressional delegation.
Sens. Patty Murray and Maria Cantwell, along with Rep. Adam Smith, all Democrats, sent a letter with the request on Thursday to Anne Marie White, DOE assistant secretary for environmental management.
The Energy Department is accepting public comments on the Draft Waste Incidental to Reprocessing (WIR) Evaluation, which considers whether the remaining waste in the 16 tanks in the C Tank Farm could be classified as low-level waste and the tanks closed by being filled with concrete-like grout and covered with above-ground caps to prevent infiltration of precipitation.
“While we understand the Draft WIR Evaluation is the natural next step from DOE’s perspective, we also recognize this is a complex decision that involves managing waste differently, reclassifying waste, and has the potential to set precedent for the 17 other tank farms at Hanford,” the lawmakers said in the letter. “A decision of this magnitude should be made in an open and transparent manner with multiple avenues for public engagement.”
Hanford’s storage tanks hold 56 million gallons of chemical and radioactive waste, left by decades of plutonium production for the nation’s nuclear weapons.
The DOE draft study is evaluating C Tank Farm, as the first of Hanford’s single-shell tank farms to be emptied to regulatory standards. The goal is to remove an average of 99 percent of the waste from Hanford’s 149 single-shell tanks, but DOE can halt retrieval if it has used three retrieval technologies until each cannot remove more material.
C Tank Farm had 1.8 million gallons of mostly sludge and salt cakes when retrieval of solids began. From 2003 until late 2017 about 96 percent of the waste was removed, leaving roughly 64,000 gallons that could be grouted inside the tanks. The waste is both in spots on the bottoms of the tanks and clinging in places to their walls.
Supporters of grouting the remaining waste within the tanks say removing more waste would be difficult without exposing workers to radiation and damaging the floors or walls of the tanks, which are already prone to leaking.
However, Seattle-based watchdog group Hanford Challenge has opposed grouting, saying DOE should continue to monitor the waste remaining in the C Tank Farm in the hope that better waste retrieval technology will be developed in the next 10 to 20 years. Grouting the waste now could prevent eventual removal with improved technology.
Grout does not effectively contain radioactive waste, according to Hanford Challenge. Water can infiltrate and the caustic materials in nuclear waste break down the grout quickly, putting groundwater and the Columbia River at risk of contamination, it said.
The Energy Department says grout has been used safely and successfully to close underground tanks with residual waste at the Savannah River Site in South Carolina and the Idaho National Laboratory.
Determining that the residual waste in C Farm could be classified and safely left in place as low-level waste is just one step in what is likely to be a multiyear regulatory process to close the tanks, DOE said. Approval from the Washington state Department of Ecology would be required, and the state agency would take public comment.
The Energy Department already has held open meetings to discuss the Draft WIR Evaluation, although none have been formal hearings with records kept of public comments. Meetings have included an all-day session in June in Richland, Wash., with a similar meeting planned in Portland, Ore., on Oct. 16. Presentations have been made at a Hanford Advisory Board committee meeting and an Oregon Hanford Cleanup Board meeting. The department also plans to participate in an evening meeting set by the Oregon Department of Energy in Portland on Oct. 16.
The federal agency has asked the U.S. Nuclear Regulatory Commission to perform an independent technical review of the Draft WIR Evaluation and the underlying performance assessment that considers how well the proposed remedy, grouting and a cap, would perform. Two additional public meetings will be held near Hanford during the NRC process, likely this month and in December, DOE said.
“DOE is committed to an open, transparent process and will consider NRC’s technical review and comments from states, tribal nations, and the public before making a final determination,” DOE said in a statement Thursday.
Cantwell, Murray, and Smith said public hearings are an important avenue for DOE both to explain the Draft WIR Evaluation and to take public comment from states, tribal nations, stakeholder groups, and the public. “We have heard from stakeholders expressing the importance of holding additional public hearings at times and locations that allow for full participation,” their letter said.
The DOE public comment period, which started June 4, has been extended for 60 days until Nov. 7. Comments can be mailed to [email protected].
