Effects of landfill leaching on water quality and biology of a nearby stream, South Cairo, Greene County, New York

A 1-kilometer stream reach receiving leachate-enriched water from a small municipal landfill in Greene County, N.Y., was studied from 1971-75 to document streamflow rates and chemical quality of the stream and ground water. The distribution of benthic invertebrates and microorganisms in the stream above the landfill was markedly different from that below it; the difference is attributed to the inflow of leachate. The Trichoptera, Ephemeroptera, and Nematomorpha have been eliminated from the reach adjacent to and below the landfill and have been replaced by large numbers of Tendipedidae and Niadidae. Certain chemical constituents, especially iron and manganese, were extremely concentrated in the ground water immediately beneath the streambed. The elevated concentrations of these and other metals may be the direct cause of the abrupt faunal shift. Algae were replaced by large masses of the iron bacterium Leptothrix in the stream reach below the landfill. (Kosco-USGS)