SCOTT MALLETTE (DOE) 516/344-5345
PETER GENZER (BNL) 516/344-3174

FOR IMMEDIATE RELEASE September 23, 1999

Brookhaven Lab Starts Up First Off-Site
Groundwater Cleanup System

Innovative technology partly funded by Department of Energy grant

The U. S. Department of Energy (DOE) and its Brookhaven National Laboratory today began operating the first of several groundwater treatment systems proposed to treat chemical contamination located beyond the Laboratory's boundaries.

Located in an industrial park just south of the site and the Long Island Expressway, the system addresses the off-site portions of a groundwater "plume," or area of chemical contamination.

The Laboratory now has five treatment systems (four on-site) working 24 hours a day to clean area groundwater. This newest system, a $3-million construction project, was partially funded with a $1.5-million grant from DOE's Office of Science and Technology in the Office of Environmental Management. The grant was established to promote the use of new and innovative technologies in site cleanups across the United States. The remaining $1.5 million was funded by DOE's environmental restoration program.

The cleanup system employs a technology known as "in-well air stripping," which works by mixing air with contaminated groundwater. This closed-loop system essentially prevents air emissions, and the contaminated water is treated below ground without ever reaching the surface. The mixing process "strips," or removes, volatile organic compounds (for example, solvents like carbon tetrachloride) from the water. The clean water exits the well and recirculates, and the air carries the volatile organic compounds, now in gaseous form, upward within the well to the surface. The air is piped out of the well and sent through a carbon filter to remove the contaminants. The clean air is then returned to the well and the cycle repeats.

In-well air stripping has proven successful at several sites across the country, including the Savannah River Site in South Carolina, Edwards Air Force Base in California, and the Massachusetts Military Reservation.

This off-site system, located in an industrial park, consists of seven in-well air stripping wells, each treating approximately 60 gallons per minute. The system is designed to operate for eight to 10 years.

This cleanup action encompasses a portion of a groundwater plume that extends from the central, developed section of the Brookhaven site into an industrial park just south of the Laboratory's southern boundary. The off-site portion of this plume is comprised primarily of carbon tetrachloride, a solvent once widely used at the Lab and in industry for degreasing equipment. This groundwater treatment system, like those operating on the Brookhaven site, is intended to clean up contaminants and minimize further migration of contaminants.

Carbon tetrachloride, which was commonly used as a dry-cleaning chemical, has been detected in on- and off-site monitoring wells at depths of 180-300 feet below land surface. Concentrations as high as 5,100 parts per billion (ppb) have been detected. The U.S. Environmental Protection Agency (EPA) and New York State drinking water standard for carbon tetrachloride is 5 ppb. A separate cleanup system, constructed in 1997, is currently addressing the portion of the plume within the Brookhaven Lab property.

Although a 1995-96 residential well sampling program in this area showed no contamination from Brookhaven above drinking water standards, DOE has connected more than 1,500 area homes and businesses to the public water supply as a precautionary measure.

The seven treatment wells, air stripping systems and associated performance monitoring wells were installed by Delta Well and Pump of Bohemia, NY. The treatment building and associated equipment were constructed and installed by Larsen and Son Construction of Smithtown, NY.

Environmental remediation at BNL is being conducted under the requirements of the federal Comprehensive Environmental Response, Compensation and Liability Act of 1980, commonly known as the Superfund law. BNL is on EPA's Superfund list primarily due to past operations that have resulted in soil and groundwater contamination. Remediation work is conducted under the framework of an interagency agreement among the New York State Department of Environmental Conservation, EPA and DOE. DOE has jurisdiction over BNL and pays for all cleanup costs.