Hydrogeology and ground-water-quality conditions at the Geary County landfill, northeast Kansas, 1988

Abstract

Chemical analyses of water from monitoring wells installed at locations upgradient and downgradient from the landfill indicate the presence of calcium bicarbonate, sodium chloride, and mixed calcium bicarbonate sodium chloride water types. For the dominant calcium bicarbonate water type, inorganic and organic constituents indicate the presence of r3educing conditions in the landfill, and increased concentrations of calcium, magnesium, sodium, bicarbonate, sulfate, chloride, ammonia, iron, manganese, and other trace elements downgradient within a leachate plume that extends northeasterly away from the landfill. The orientation of the long axis of the leachate plume does not coincide with the direction of groundwater flow, based on measurements of water-level altitude, possibly due to the effect of abundant rainfall and high river stages at other times of the year or preferential flow in very transmissive zones, and thus may indicate the dominant direction of groundwater flow. None of the organic-constituent or inorganic-constituent concentrations exceeded primary drinking water standards, but iron and manganese concentrations exceeded secondary drinking water standards. Concentrations of benzene, vinyl chloride, and 1,2-trans-dichloroethene exceeded Kansas notification levels. 28 refs., 20 figs., 9 tabs.