Two pump-and-treat systems are planned at Brookhaven National Laboratory's south boundary. Both systems include the installation of groundwater extraction wells. The water will be pumped back to the central portion of the Lab where it will be treated and discharged.
Pump-and-treat is being installed to treat groundwater contamination and to prevent further migration off-site. The first system, expected to be operational by the end of 1996, is located near BNL's southeast boundary within Operable Unit I. The sources of this groundwater contamination are the Current Landfill and the Hazardous Waste Management Facility.
The second system, located within Operable Unit III, is approximately 3000 feet west of the Operable Unit I system. It is scheduled to start up in June, 1997. Work has started on the installation of the electric distribution system, access road and water piping. Construction of the treatment system and well installations will be completed in the spring of 1997. The source of this contamination is being investigated.
Pump-and-treat works by extracting contaminated groundwater and pumping it to an "air stripping" facility where volatile organic compounds are separated from the water. The clean water is then recharged (returned to the ground) and the volatile organic compounds are released into the air via an air stripping stack at a concentration that is below state and federal emission standards.
To ensure that the pump-and-treat system is working effectively, groundwater monitoring wells will be sampled and analyzed regularly. The U. S. Department of Energy, the U.S. Environmental Protection Agency and the N.Y. S. Department of Environmental Conservation will oversee all monitoring. Brookhaven National Laboratory and the U.S. Department of Energy expect the pump-and-treat system to operate from seven to 12 years before design goals are met. At that time, the system will have reduced the contamination to such low levels that no further remediation is practicable. Any remaining groundwater contamination will be remedied by the natural processes of degradation and dilution over time.