While the Department of Energy is increasingly interested in using grout to solidify some low-level radioactive waste left from decades of plutonium production at its Hanford Site in Washington, operation of such a facility would not begin before the 2030s, according to a recent report.
Various scenarios from DOE and its state regulator, the Washington Department of Ecology, envision using concrete-like grout to solidify much of Hanford’s lower-risk radioactive tank waste as early as 2034 or as late as 2050, according to River Protection System Plan 10, published over the holidays.
DOE and the state publish an update to the System Plan for Hanford every three years and the latest 390-page version was posted Dec. 27. The 390-page document was posted online.
In various studies, grout has been identified as a viable backup for portions of Hanford’s low-level waste that cannot be suspended in solid glass by the Bechtel-built Waste Treatment and Immobilization Plant, the current disposal pathway for such waste. DOE has agreed to a Government Accountability Office recommendation to include cost estimates for grout in future system plan updates.
There is an estimated 56 million gallons of liquid waste held in underground tanks at Hanford. The Waste Treatment Plant will, eventually, vitrify all of the high-level waste there into a glass-like solid.
The plant will also solidify 40% or more of the low-level waste, which accounts for most of the volume, but far fewer radionuclides, of Hanford’s liquid tank waste, DOE has said. Direct-Feed-Low-Activity Waste Facility operations are targeted for early 2025.
In research by the Savannah River National Laboratory in South Carolina and the National Academies of Science, grout has been deemed a reliable and more-economical option than building a second vitrification plant at Hanford. State officials have said they are open to considering grout as a backup to glass.
