Interim salt waste treatment at the Savannah River Site in South Carolina has been shut down, as the Department of Energy prepares to start up the larger-scale Salt Waste Processing Facility (SWPF) in December.
Since April 2017, workers at the 310-square-mile site have been operating the Actinide Removal Process (ARP) and Modular Caustic Side Solvent Extraction Unit (MCU): two demonstrations that have operated jointly to process radioactive liquid salt waste. The combined demonstration removes radioactive isotopes, cesium, strontium, and actinides from the salt waste and sends them to a separate processing facility where they are processed with sludge waste. Meanwhile, ARP/MCU sends the decontaminated salt waste to the Saltstone Disposal Facility for permanent on-site storage.
In its 11-year tenure, the system processed 7.4 million gallons of salt waste, which has translated to 1,827 canisters of treated material and the operational closure of six of the site’s 51 underground waste storage tanks.
“For more than a decade, this demonstration project has proved invaluable for the operation of SWPF and allowed for the uninterrupted operation of the liquid waste mission,” SRS Manager Michael Budney said in a press release.
The Savannah River Site liquid waste mission covers processing of more than 35 million gallons of radioactive waste generated by Cold War nuclear-weapon operations, along with closure of the storage tanks and decommissioning of related facilities and equipment. About 90 percent of that waste volume is salt waste and the rest is sludge, which is treated using the Defense Waste Processing Facility (DWPF). All told, the liquid waste mission is expected to last until 2039 with a lifecycle cost of $33 billion to $57 billion.
With the pilot process now shut down, waste transfers lines are being rerouted to the 140,000-square-foot Salt Waste Processing Facility, a $2.3 billion structure that should increase waste processing from 1.5 million gallons a year to 6 million.
