The Washington state Department of Ecology in June formally signed off on a Department of Energy plan to solidify into a concrete-like grout up to 2,000 gallons of low-level liquid radioactive waste from the Hanford Site.

Filtering of cesium and other radionuclides, what DOE calls pretreatment, will happen onsite at the former plutonium production complex, grouting and final disposal will occur out of state, according to documents posted online.

Ecology gave its blessing to the Test Bed Initiative Demonstration Project in a June 18 letter to DOE’s Hanford Site manager Brian Vance and Wesley Bryan, president of, Washington River Protection Solutions, the Amentum-led contractor in charge of Hanford’s underground tanks of liquid radioactive waste.

The final Dangerous Waste Research, Development and Demonstration Permit takes effect July 18, the state Ecology Department said in the letter. The permit will remain in effect through July 18, 2025.

DOE and Washington River Protection Solutions applied for the demonstration permit, designed to build upon an earlier three-gallon pilot test, on June 8, 2023, according to the letter.

Gerry Pollet, a member of the Washington state legislature, who is also executive director of the advocacy group, Heart of America Northwest, said via email Monday to Exchange Monitor he generally supports the demonstration project. But the group could challenge the state’s decision to ship the waste in liquid form rather than solidifying it “at the available commercial treatment plant adjacent to Hanford,” a reference to the Perma-Fix Environmental facility in Richland, Wash.

Although not mentioned in the permit, EnergySolutions in Utah and Waste Control Specialists in West Texas, have been frequently discussed by DOE as final disposal sites for grouted waste from Hanford.

The 48-page permit can be found here and the 28-page permit conditions here.