SRS works with the UGA laboratory to combat difficult groundwater contamination | News
Savannah River Nuclear Solutions turned to a local lab to treat a difficult plume of contaminated groundwater resulting from Cold War operations at the Savannah River site.
“We have some of the most creative and innovative engineers and scientists in the world tackling these problems, and we are asking them to apply their expertise and knowledge to this new task, working with the Ecology Laboratory of the Savannah River from the University of Georgia to make it a reality,” said Jeff Thibault, SRNS engineer.
During the Cold War, sewage containing traces of radioactive iodine-129 was discharged into pond-like basins near two nuclear fuel processing facilities at SRS. Wastewater slowly migrated through the soil and into the water table.
SRNS has developed highly effective remediation techniques for treating a variety of chemical and radioactive contaminants at SRS, and many of these technologies have been adopted by other sites within the Department of Energy complex. However, a new technique is needed for the latest groundwater contamination challenge.
“The clean-up technology currently in use binds iodine radionuclides to soil sediments in the aquifer, effectively locking them in place,” Thibault said. “Unfortunately, this same technology cannot be used to treat the leading edge of the plume, which has reached a large marshy area at SRS. This represents a new cleaning challenge for us, as the contamination of surfaces in the swamps. »
The goal is to identify a material that can be buried at the edge of the marsh, creating a permeable barrier to immobilize iodine underground before it rises to the surface in the marsh.
“We want to create a strong treatment barrier that will let groundwater through, but not iodine-129,” he said.
John Seaman, professor-researcher at SREL, tested 11 promising materials for the permeable barrier. SREL scientists are working with SRNS engineers to test four of these materials in the field using contaminated water from the aquifer. The materials are zero-valent iron, a porous iron composite, granular activated carbon, and a mixture of iron and carbon.
“We hope to obtain positive results from this first phase of testing. We also have funds in our budget for next year to test other absorbents or other combinations of absorbents,” said Thibault. “I am very interested in the mix of materials. Zero valence iron may be good. But zero valence iron with carbon can be fantastic.
In addition to providing advice and strategies for remediation technologies, SREL provides research expertise in wildlife ecology, disease ecology, biogeochemistry, and forestry and conservation.