Researchers To Explore Microbes' Potential For Pollution Cleanup

DOE has selected its Oak Ridge National Laboratory (ORNL) to operate a field research center located in Bear Creek Valley next to the Oak Ridge Y-12 Plant. Scientists will use the center to conduct long-term field studies to better understand the biological, geologic and chemical processes that affect the way microorganisms may be able to clean up groundwater and subsurface sediments contaminated with radionuclides and metals.

The research will help DOE address a unique set of challenges associated with cleaning up huge amounts of groundwater and soil at its former weapons production sites around the country. These sites contain complex mixtures of pollutants, including radioactive wastes.

"We hope to better understand how microbes interact with groundwater and soil and the mechanisms of how the microorganisms can be used to consume and contain contaminants," said ORNL's David Watson, who will manage the research center for the lab.

The center includes a 243-acre contaminated area and a 404-acre uncontaminated background area. Different parts of the center have different mixtures of pollutants. Scientists will do research in small test plots, less than one acre in size. Experiments will include injection of very small quantities of tracers, nutrients or microorganisms. The background area will be used for comparison or control studies.

For the first six months, center staff will perform hydraulic testing, tracer testing, groundwater and sediment sampling and other activities to better characterize the contaminated and background areas. This information will help scientists identify specific plots for their field studies, expected to take place over the next five to 10 years. Teams of researchers from universities and DOE laboratories, including ORNL, will conduct the field studies.

The center's research will be useful because, while bioremediation represents a potential low-cost approach for cleanup, researchers lack a fundamental understanding of how bioremediation works. For example, while it might work for a single contaminant, it might not work as well when contaminants are mixed. Similarly, it might work in one type of geologic environment, but not in another. Researchers will use the center to develop an understanding of the complex factors affecting bioremediation. They will also focus on ways to enhance the reactions of microbes. They will not, however, introduce any genetically engineered organisms to the site.

The department selected the Oak Ridge site following an extensive peer review process and an environmental impact review under the National Environmental Policy Act. The department published an Environmental Assessment for comment earlier this year and issued a Finding of No Significant Impact in April.

DOE funding of $900,000 will support the first year of operation at the center. Information on the program is available on the World Wide Web at: http://www.lbl.gov/NABIR

ORNL is a DOE multiprogram facility operated by UT-Battelle.