For years the Snake River Plain Aquifer was considered to be unsafe as it had been a location to design, build and test nuclear reactors in 1949. After three decades of cleanup, the Department of Energy (DOE) reported that the aquifer and the DOE’s Idaho National Laboratory site are “considerably safer."
According to a release by the DOE, 30 years ago the DOE, State of Idaho and the U.S. Environmental Protection Agency (EPA) signed the Federal Facility Agreement and Consent Order (FFA/CO). This outlined a plan to investigate and clean up more than 500 waste areas within an 890-square-mile area. The waste sites included unlined wastewater disposal ponds, debris piles, radioactive groundwater plumes, buried barrels and boxes of radioactive and hazardous materials. There were even unexploded materials at the site that were taken care of.
“This agreement has stood the test of time,” said Connie Flohr, EM manager for the Idaho Cleanup Project. “It provides the regulatory framework that we still use today to complete our cleanup work.”
All of the sites have been evaluated and most of the cleanup at the site has been completed. The release said that the project involving the removal of 10,250 cubic meters, or 49,000 drums, of radioactive and hazardous waste will be 18 months ahead of schedule. This is from an unlined Cold War landfill called the Subsurface Disposal Area.
Another aspect was using three vacuum extraction units to remove 258,000 pounds of solvent vapors from under the landfill and destroy them using catalytic oxidation technology. This was turned off in August 2020 to see if vapor concentrations would meet remediation goals, which sampling and analysis showed did so early.
These projects were designed to protect the aquifer that is 585 feet below the landfill.
An area of the site has 825 million gallons of water that were treated over the past 20 years, as well. Biomediation is also in progress, which involves injecting sodium lactate or something similar into a containment plume to create favorable conditions so microorganisms can feed on the water. A well was also completed this summer that targets a “residual trichloroethylene source zone” that could not be accessed with what existed.
In the 2000s, there was also a 510-cubic-yard Idaho Comprehensive Environmental Response, Compensation and Liability Act Disposal Facility created. This allowed the DOE to consolidate waste material and manage the landfill.
Next on the agenda is to exhume buried waste in a landfill amount 5.69 acres that pose risk to people and the environment.
“This completion, coupled with the successful vacuum extraction of solvent vapors from it, protects Idaho residents, wildlife and the environment by safeguarding the Snake River Plain Aquifer,” the release states.
