The Department of Energy aims to use an advanced new solvent by the end of fiscal 2025 to improve the numbers at the Salt Waste Processing Facility at the Savannah River Site in South Carolina, a cleanup contractor boss told a federal advisory board Tuesday.
Other glitches at the Salt Waste Processing Facility (SWPF) should be fixed by May 2024, allowing the plant to start use of Next Generation Solvent, Mike Borders, optimization and integration director for contractor Savannah River Mission Completion, told the Savannah River Site Citizens Advisory Board.
The new solvent, designed to remove more cesium, is a key to DOE’s drive to treat nine million gallons of salt waste annually with SWPF, said Borders, a manager for the environmental prime.
The advisory panel heard Monday the prior target was May 18 to start using the Next Generation Solvent, but the state recently approved an extension into fiscal 2026. “SWPF is our critical path to finishing the mission in the salt waste,” targeted for 2037, Borders said.
“Right now, we are in the four-and-a-half-million-gallon-a-year-rate and continuing to climb our way up,” Borders said.
The SWPF will require 73% availability to reach an average of 9-million-gallons annual throughput, a DOE spokesperson said in a Wednesday email to Exchange Monitor. The plant is currently about 60%, the spokesperson said.
The SWPF separates high-activity waste from low-level waste and in the process reduces the volume of high-level waste sent on to the Defense Waste Processing Facility for conversion into a glass form, according to DOE. When the plant, built by Parsons, started radiological operations in October 2020, DOE hoped it might treat between four-and-six million gallons during its first full year of operations.
The actual first-year performance, which was before BWX Technologies-led Savannah River Mission Completion took over in March 2022, was two-million gallons, Borders said. The contractor is working to increase SWPF availability by cutting downtime, he said.
The contractor has said SWPF was unavailable for 50 days during the past year. Undissolved material including monosodium titanate, a chemical additive to the processing system, can gum up the works, reduce efficiency and increase downtime needed to flush out the system, Savannah River Mission Completion said in a May 4 press release.
Among other tweaks being made by the contractor is decreasing the volume of the monosodium titanate additive by 75%. The goal is to cut SWPF downtime by about two-thirds, according to the release.
Recent periods of peak performance give reason for optimism, Borders said.
During one seven-day period in March, the SWPF processed 146,000 gallons of waste, Borders said. If the plant could keep this up over 52 weeks it would equal about 7.6 million gallons per year, he added.
