Long-idled design work resumed this summer on the high-level waste portion of the Waste Treatment and Immobilization Plant at the Department of Energy’s Hanford Site in Washington state, according to the Defense Nuclear Facilities Safety Board.
After August workshops, prime contractor Bechtel National and DOE created what they call the “HLW [High Level Waste] Firm the Foundation Team” to use lessons from the plant’s Low Activity Waste facility to guide completion of the high-level design, the Defense Nuclear Facilities Safety Board (DNFSB) said in a Nov. 11 weekly report.
The team “is moving the project away from the previous design-build approach to developing a request for proposal for design completion, followed by construction and commissioning,” according to the DNFSB.
Two large facilities at the Waste Treatment plant, one for pretreatment of the tank waste and for treatment of the high-level radioactive waste, have been on hold for a decade while DOE addresses safety questions about build up gas in pipes and vessels that pose an explosion risk at the plant.
The work was held up in 2012 by then-Energy Secretary Steven Chu in order to allow for design changes to mitigate the explosion risk.
In July 2018, the U.S. Army Corps of Engineers reported that construction of the facility was still about 40 percent complete. The Government Accountability Office cited the Corps document in a May 2020 report to congressional committees.
In each of fiscal 2021 and fiscal 2022, DOE’s Office of River Protection at Hanford received $25 million for the high-level vitrification facility at the Waste Treatment Plant, an amount that would spike to $316 million under the Joe Biden administration’s budget request for fiscal 2023.
This facility is designed to receive high-level waste from underground tanks at Hanford and solidify it into a glass form. The canisters of vitrified waste will be stored on-site until a final Yucca Mountain-style geological repository is available, according to the DOE.
There are 56 million gallons of radioactive and chemical tank waste at Hanford left over from decades of plutonium production.
While 90% of the volume is low-level, the high-level waste accounts for most of the radionuclides, according to DOE.
