AIKEN, S.C. (Aug. 8, 2024) – A team of engineers and scientists was recognized recently for their integrated effort in developing and deploying a first-of-a-kind separations chemistry that is remediating millions of gallons of radioactive waste through the Salt Waste Processing Facility (SWPF) at the Savannah River Site (SRS).
The American Chemical Society (ACS) recognized the team of seven individuals, representing the US Department of Energy (DOE), current SRS liquid waste contractor Savannah River Mission Completion (SRMC), Savannah River National Laboratory (SRNL), Oak Ridge National Laboratory (ORNL), and, Argonne National Laboratory, as “Heroes of Chemistry” for making the world better through their effort, ingenuity, creativity, and perseverance.
The winning team includes former DOE-Savannah River Technology Development Lead and Salt Program Manager Patricia Suggs, SRMC Vice President and Chief Engineer Tom Burns, SRMC Nuclear Safety Officer and Engineering Integration Director Cliff Conner, SRMC Technical Advisor Manager Ryan Lentsch, former SRNL Actinide and Separations Sciences Director Samuel Fink, former SRNL Senior Advisory Scientist David Hobbs, ORNL Corporate Fellow Bruce Moyer, and the late ANL Engineer Ralph Leonard.
The ACS Heroes of Chemistry award recognizes the role of industrial chemical scientists and their companies in developing successful commercialized products embedded with chemistry for the benefit of humankind.
This winning team has few peers in developing unique nuclear chemical processes at a test-tube scale and then implementing those processes successfully at full scale in a nuclear facility, according to Burns.
“It is an incredible honor to be presented the Heroes of Chemistry award from the American Chemical Society,” Burns said. “The award winners have given decades of dedication to the discovery, development and deployment of the Salt Waste Processing Facility separations chemistry, a process that is benefitting the health, environment, and safety of humanity.”
From first-of-its-kind flowsheet development to selection and deployment of a novel chemical process, the winning team members contributed both leadership and technical expertise leading to the long-term success and innovative science behind the SWPF project.
Because of the ingenuity of this team, SWPF is successfully operating as the key facility treating the remaining tank waste at SRS. Since beginning operations in 2020, SWPF has treated more than nine million gallons of waste.
Suggs, currently a senior chemical engineer with S&K Logistics Services, said her time in the lead-up to SWPF operations was a highlight in her career.
“In any career, you want to work on projects that have a great impact on the mission,” Suggs said. “The work we did to bring the chemistry and processes alive in SWPF was some of the most challenging and most rewarding work I’ve ever experienced. There is no doubt this workhorse facility will serve as a special achievement that will lead to more breakthroughs in the protection of people and the environment.”
Approximately 33 million gallons of radioactive waste remains at SRS as a by-product of Cold War-era weapons production, space exploration, and scientific experimentation. It is stored in two tank farms, which are groupings of underground waste tanks at SRS.
SWPF separates and concentrates the highly radioactive portion of the tank waste — mostly cesium, strontium, and actinides — from the less radioactive salt solution. The process begins by transferring the waste from the two tank farms to SWPF, where it undergoes a two-step separation process.
The first step removes strontium and actinides (uranium, plutonium, etc.) from the waste. The second step, known as Caustic Side Solvent Extraction, removes radioactive cesium.
After the separation process is completed, the concentrated, highly radioactive waste is sent to the nearby Defense Waste Processing Facility to be immobilized in glass and stored in stainless steel canisters onsite until a federal repository is established. The decontaminated salt solution separated at SWPF goes to the Saltstone Production Facility to be mixed with dry materials, creating a grout that is pumped into saltstone disposal units and solidifies into a monolithic, non-hazardous form safe for permanent disposal on site.
SRNL played a vital role in the development and deployment of the technology from the inception of the combined technologies. In addition to coordinating research with the partner national laboratories and universities, SRNL led development of the technologies for removing strontium and the actinides, as well as maturing the engineering scale filtration steps.
“At SRNL we put science to work to protect our environment and we are proud to see this recognition of Samuel Fink’s and David Hobbs’ groundbreaking work in separations chemistry,” said Vahid Majidi, director, Savannah River National Laboratory. “Their work has paved the way for the adoption of disposition technologies across the DOE enterprise that make our world cleaner and safer, while reducing costs and schedule.”
ORNL’s Moyer led the chemical development of the cesium extraction process starting from fundamental principles in solvent extraction. The matured process began to operate at pilot scale at SRS to remove cesium from 7.5 million gallons of legacy nuclear waste. This process, known as the Actinide Removal Process/Modular Caustic Side Solvent Extraction Unit, operated from April 2008 to May 2019.
An aerial view of the Salt Waste Processing Facility at the Savannah River Site.