Ground-water flow and solute transport at a municipal landfill site on Long Island, New York – Part 1: Hydrogeology and water quality

Hydrogeology and water quality in a 4 sq mi area surrounding the Brookhaven landfill site in the Town of Brookhaven, New York, were studied in 1981-83. The 60-acre sanitary landfill at the site was excavated in highly permeable glacial outwash that forms the upper glacial aquifer and is lined with a polyvinyl chloride membrane. Groundwater beneath the site is under water table conditions and flows southeast at approximately 1.1 ft/day. Samples from wells downgradient indicate that leachate has entered the aquifer despite the liner. A plume 3,700 ft long , 2,400 ft wide, and at least 90 ft thick was delineated based on specific conductance data. Water quality in the Magothy aquifer and in Beaverdam Creek, a groundwater fed stream 2,000 ft southeast of the landfill site, does not appear to be affected. (USGS)