The Department of Energy is asking state regulators for another six months to start operating a plant to treat high-level radioactive sodium-bearing waste at the Idaho National Laboratory.
In a Sept. 29 letter, DOE asked the Idaho Department of Environmental Quality to extend the formal state milestone to March 31, 2023 to process sodium-bearing waste at the Integrated Waste Treatment Unit (IWTU).
The letter was addressed to Natalie Walker, hazardous waste bureau chief at the state Department of Environmental Quality.
In addition, DOE and the Jacobs-led contractor Idaho Environmental Coalition want the state to extend the milestone for production of the first 100 canisters to June 30, 2023. The prior deadlines were last week, Sept. 30, for turning out the first canister and Dec. 31 for completing the first 100. The DOE acknowledged last week it would miss the Sept. 30 target.
For his part, DOE Office of Environmental Management senior adviser William (Ike) White said Wednesday he remains cautiously optimistic the IWTU will begin producing canisters this year.
“We hope to begin treating tank waste at Idaho by the end of the year as IWTU comes online,” White told the Energy Technology & Environmental Business Association conference in Knoxville.
The plant is designed to convert 900,000 gallons of sodium-bearing waste stored in underground tanks at the DOE facility in Idaho into a solidified granular form for eventual disposal.
The feds said due to “several complexities unforeseen at the time the current milestones were established” in July 2021, the IWTU would miss the startup and conversion milestones.
Delayed liquid nitrogen deliveries in early 2022 hurt the first IWTU attempt at a sustained confirmatory trial run. Granular activated carbon beds also had to be replaced in 2021. De-fluidizing of the carbon reduction reformer caused an automatic shutdown in early 2022, DOE wrote. There was also a December incident where a worker installed a valve-position indicator backwards.
On its second attempt, the ITWU did successfully complete a 65-day confirmatory run, on July 27, DOE noted in the letter. During that practice run, the plant processed 137,000 gallons of simulant designed to mimic the radioactive waste, DOE said in the letter.
Initial construction of the IWTU occurred in 2012 but the facility never worked as designed. The plant has been substantially overhauled and re-engineered since then.
