Leachate plumes in a highly permeable aquifer

Two landfills, 27 and 41 years old, were studied and found to have plumes of leachate-contaminated ground water extending 10,600 and 5,000 ft (3,200 and 1,500 m), respectively, from the site of deposition in the upper glacial aquifer on Long Island, New York. The plumes sink to the bottom of the aquifer, which is 70 ft (21 m) below the water table at the 27-year old site and 170 ft (52 m) below at the 41-year old site. The aquifer has a hydraulic conductivity of 270 ft per day (80 m per day).