The Salt Waste Processing Facility at the Department of Energy’s Savannah River Site has performed largely as expected, processing more than one million gallons of radioactive waste during its first eight months of operation, the DOE reported on June 8. The SWPF is being used to treat the majority of the site’s remaining liquid radioactive waste, generated from the production of nuclear materials.
The first batch of radioactive waste was transferred from underground storage tanks to the SWPF on October 5, 2020, beginning “hot” commissioning of the facility. In its first month of operation, SWPF received nearly 86,000 gallons of waste.
The ability to process the waste will allow the DOE to make substantial progress toward emptying the site’s remaining 43 underground waste tanks and removing them from service.
“The success of SWPF to date enables the department to begin planning for closing the remaining SRS waste tanks at an unprecedented rate,” said Jim Folk, DOE-Savannah River assistant manager for waste disposition.
The process: Once the waste is received at SWPF, it undergoes a two-step cleanup process to separate highly radioactive waste from the less-radioactive salt solution. The first step removes strontium and actinides, such as uranium and plutonium, from the waste. The second step, known as caustic side solvent extraction, is designed to remove radioactive cesium.
After the separation process is complete, the concentrated high-activity waste is sent to the site's Defense Waste Processing Facility, where it is converted into a solid glass form through the vitrification process and stored in 10-foot-tall stainless steel canisters. The decontaminated salt solution is mixed with cement-like grout at the site's Saltstone Production Facility for disposal onsite. The amount of salt waste processed has exceeded 1.1 million gallons, according to the DOE.
SWPF completed testing and hot commissioning on January 17 and has been fully integrated with the other SRS liquid waste facilities.
Slow and steady: Parsons Corporation, which designed and built the SWPF, is operating the facility during its first year of service. The DOE said that Parsons will operate SWPF conservatively during this time, ensuring that the facility runs as designed, and identifying and addressing any issues that may arise.
When the DOE takes over operations later this year, it expects to operate the SWPF at a rate of 6 million gallons per year. By 2031, it is expected that nearly all of the salt waste inventory at the site in South Carolina will be processed, and the site’s F-Tank Farm will be nearly empty.