DOE liquid waste contractor Savannah River Remediation is moving forward with Saltstone Disposal Unit projects to support the Salt Waste Processing Facility at the Savannah River Site.
The Department of Energy’s Office of Environmental Management (EM) has authorized the use of a second mega-volume saltstone disposal unit (SDU) at the Savannah River Site in South Carolina. Savannah River Remediation (SRR), EM’s liquid waste contractor at SRS, received Critical Decision-4 for Saltstone Disposal Unit 7, marking the final step in the approval process before beginning operations.
SDU 7 will receive decontaminated salt solution treated at Savannah River’s Salt Waste Processing Facility (SWPF) and Saltstone Production Facility (SPF). SDU 7 is scheduled to receive its first grout in this fiscal year, which began October 1.
Waste treatment: Salt waste at SRS is decontaminated at the Salt Waste Processing Facility through processes that remove radioactive isotopes, including cesium, strontium, and actinides. The treated solution is then sent to the Saltstone Production Facility, where it is mixed with dry slag and fly ash to form a grout. The grout is pumped to the aboveground SDUs, where it hardens to form saltstone.
The design and construction of SDU 7 is based on SDU 6, the first mega-volume SDU, which began operating in August 2017. SDUs 6 and 7 each have a 32-million-gallon capacity.
EM said that SRR is also making progress on the next mega-sized SDUs. Construction is ongoing at SDU 8 and 9. EM authorized the construction of SDUs 10, 11, and 12 to begin last month.
They said it: “The safe completion of the SDU 7 project ahead of schedule and under cost, combined with the approval to construct the last three SDUs, facilitates completion of the mission to remove and treat all remaining high-level waste stored in South Carolina,” said Shayne Farrell, federal project director for Savannah River’s SDUs.
SRR chief operating officer and deputy project manager Mark Schmitz added that building the SDUs at an accelerated rate benefits the liquid waste program at SRS.
“Constructing saltstone disposal units concurrently optimizes crews and resources used on the adjacent structures, ultimately cutting costs for the program,” Schmitz said. “Saving money on such a large and critical component of the liquid waste system is a win for Savannah River Remediation, DOE, and especially for the taxpayers.”
