PADUCAH, Ky. – An innovative environmental remediation technology used by the U.S. Department of Energy – the Lasagna^TM Process – appears to have exceeded it goals at the Paducah Gaseous Diffusion Plant.  Developed for use at Paducah, the system has potential to be used to remove similar contamination at other sites.

Originally slated to run as long as three years, Lasagna was shut down after just two years when preliminary results indicated the process had removed more trichloroethylene (TCE) from beneath the surface of a one-acre site than had been expected.  TCE is a solvent identified as a groundwater contaminant at many locations in the United States.

"This shows that we can develop breakthrough technologies that allow us to clean up contamination more quickly and cost-effectively," said W. Don Seaborg, DOE’s Paducah Site Manager. "We are extremely pleased that Lasagna achieved its goals in such a short time and was successful in removing this TCE before it could get to the groundwater."

Lasagna works by electro-osmosis, sending electric currents through buried electrodes.   The electricity moves water particles containing TCE to treatment zones where the solvent is captured and broken down into harmless components.

The Lasagna site at the plant was used as a cylinder drop test area in the 1970s. Concerned about the safety of transporting cylinders containing depleted uranium, DOE conducted a series of tests to ensure the metal containers would not break open in a traffic accident.  TCE was used in the tests and a large quantity remained in the soil.

The site’s gravel and sandy clay loam soil prevented the use of other remedial technologies and excavation was viewed as prohibitively expensive.  The Paducah installation was designed to remove TCE to a depth of 45 feet, where a clay layer slowed downward movement.

Following two successful demonstrations at Paducah during the mid-1990s, a full-scale deployment of Lasagna was ordered.  The system was built in 1999 and began operations at the end of that year.

TCE concentrations in the soil were as high as 1,760 parts per million (ppm).  The goal of the project was to reduce TCE to less than 5.6 ppm. Preliminary results indicate Lasagna exceeded that goal.  Final site testing will be conducted in May and June, and the final report on the project is expected by September.

Geologic conditions at other contaminated areas of the Paducah Gaseous Diffusion Plant do not favor the Lasagna technology.  The system should work well at other sites where TCE or similar contaminants are held at relatively shallow depths by a geologic feature which inhibits movement toward groundwater (an "aquitard"), such as a clay layer or unfractured bedrock.

Lasagna was developed and tested over several years by a public-private partnership that included DOE, the Environmental Protection Agency, Monsanto, duPont, and General Electric.

-DOE-

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