Abstract |
The Northwest 58th Street Landfill, one of three NPL sites that comprise the Biscayne Aquifer Superfund Study, is a one-square-mile site in northwest Dade County, Florida, which is bordered by a rock pit operation and a resource recovery plant. The site is located in an area where the ground water table is two to three feet below the ground surface. From 1952 to 1982, the site operated as a municipal landfill receiving approximately 60,000 tons of waste in 1952 and increasing annually over the thirty years of operation to over 1,000,000 tons per year in the 1980s. Small quantities of hazardous materials from households (e.g., pesticides, paints, solvents, etc.) was considered to be municipal waste and also disposed of at the landfill. In 1975, the landfill operation initiated a program of providing daily cover to the site; however, prior to this, the operation did not compact wastes or add daily cover. As a result of earlier practices, the landfill is believed to be saturated with water so that the earlier practices, the landfill is believed to be saturated with water so that the volume of rainfall entering the land equals the volume of leachate released. Since October 1982, the landfill has only received debris, quarry wastes an water paint sludges. |