The Department of Energy favors continued reliance on Mother Nature, with monitoring and other steps, to clean up groundwater within large chunks of the former uranium enrichment property at the Oak Ridge Site in Tennessee, a federal advisory committee heard last Wednesday.
Largely leaving the contamination alone and checking it regularly to “attenuate” or reduce the concentration of contaminants at the K-31/K-33 area would only cost $1.8 million over 15 years, said Roger Petrie. Petrie, DOE’s local Federal Facilities Agreement projects manager, addressed the Oak Ridge Site Specific Advisory Board on June 15.
By contrast, using pump and treat technology that extracts and treats groundwater with the highest concentrations of chromium and nickel, would cost $11.2 million over 10 years, Petrie said. The figures include both the capital costs and the annual operations expenses of each method according to Petrie’s meeting materials.
Land use controls will be implemented to curb use of groundwater and provide notifications to future landowners concerning the presence of contamination. The controls would remain in place until the groundwater meets the “remedial action objectives” for contamination agreed upon by DOE, the U.S. Environmental Protection Agency and the state of Tennessee, according to Petrie’s presentation.
“Over time it has been shown that the level of contaminants have been coming down” anyway, Petrie said. DOE believes “nature is taking care of part of the problem itself,” he said.
Petrie told the panel natural attenuation, the DOE-preferred approach, is EPA-approved for groundwater remediation. The DOE official said this natural, cheaper option would free cleanup dollars for other uses at Oak Ridge.
The three agencies conducted a 45-day public comment period that ended June 12 and a copy of the proposed action alternatives can be found here.
Buildings K-31 and K-33 were used to produce low-enriched uranium at Oak Ridge. The 1950s vintage K-31 and K-33 buildings stopped operating in the mid-1980s and were torn down in 2015, according to DOE.
The two buildings were among five major process buildings, including K-25, which held gaseous diffusion equipment within the area now known as the East Tennessee Technology Park at Oak Ridge.
