The US Department of Energy’s Office of Environmental Management (EM) announced it has completed the hot commissioning testing phase of operations at the Salt Waste Processing Facility (SWPF) at the Savannah River Site (SRS).
Completion of the hot tests "validated radiation shielding, environmental emissions, and product waste acceptance requirements while processing over 320,000 gallons of radioactive liquid waste from the SRS tank farm," EM said. It signals the facility’s entrance into fully integrated operations with the other SRS liquid waste facilities.
Parsons Corporation, the contractor that designed and built the first-of-a-kind facility, will now operate SWPF for one year, beginning January. The facility is expected to process up to 6 million gallons of waste during the first year of operations.
SWPF is designed to significantly increase the Savannah River site’s ability to empty and close radioactive waste tanks and dramatically reduce that legacy environmental risk.
“The start of operations enables DOE to now close waste tanks at an unprecedented rate,” said DOE Savannah River Operations Office Manager Mike Budney.
Processing of the radioactive waste began in early October and by mid-November 2020, SWPF had begun processing undiluted feed from Tank 49 in H Tank Farm. All hot commissioning testing objectives were met on schedule and without incident, EM said. In total, over 450,000 gallons of decontaminated salt solution have been transferred from SWPF.
The remediation of radioactive waste begins by transferring the waste from H Tank Farm to SWPF, where it undergoes a two-step separation process. 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 caesium. After the separation processes are completed, the concentrated high-activity waste is sent to the nearby Defence Waste Processing Facility (DWPF). The decontaminated salt solution is mixed with cement-like grout at the nearby Saltstone Production Facility (SPF) for disposal onsite.
Transfers of these waste streams out of SWPF were also completed during hot commissioning. The decontaminated salt solution from SWPF has been sent to the SPF. The actinide-laden sludge solids and the caesium-laden strip effluent radioactive waste streams, removed from the salt waste by SWPF, have been sent to the DWPF, where the concentrated waste will be immobilized in glass and stored in stainless steel canisters onsite until a federal repository is made available.
Now that SWPF is fully operational, it is expected that nearly all of the salt waste inventory at SRS will be processed by 2030.
Photo: An aerial view of the Salt Waste Processing Facility (Credit: DOE)