Ground-water quality in the Davie Landfill, Broward County, Florida

Ground-water adjacent to a disposal pond for septic tank sludge, oil, and grease at the Davie landfill, Broward County, Florida was tested for a variety of ground-water contaminants. Three wells adjacent to the disposal pond yielded water rich in nutrients, organic carbon and many other chemical constituents. Total coliform bacteria ranged from less than 100 to 660 colonies per 100 milliliters in samples collected from the shallowest well (depth 20 feet). At well depths of 35 and 45 feet bacterial counts were less than 20 colonies per 100 milliliters or zero. Concentrations of several constituents in water samples collected from the wells downgradient from the landfill, disposal pond, and an incinerator wash pond were greater than in samples collected from wells immediately upgradient of the landfill. A comparison of sodium-chloride ion ratios indicated that downgradient ground-water contamination was related to the incinerator wash water pond rather than the septic tank sludge pond. (Woodard-USGS)