This report summarizes ground-water-quality data, for Wisconsin, stored in the U.S. Geological Survey 's computer system (WATSTORE). The summary includes water-quality data for 2,443 wells which tap one of the State 's three major aquifers (sand and gravel, Silurian dolomite, and sandstone). Data for dissolved solids, hardness, alkalinity, calcium, magnesium, sodium, potassium, iron, manganese, sulfate, chloride, fluoride, and nitrate are summarized by aquifer and by county, and locations of wells where data are available are shown for each aquifer. Calcium, magnestium, and bicarbonate (the principal component of alkalinity) are the major dissolved constituents present in Wisconsin 's ground water. High iron concentrations and hardness cause ground-water-quality problems in much of the State. Statewide summaries of trace constituent (selected trace metals, arsenic, boron, and organic carbon) concentrations show that they impair water quality in only a few isolated wells. A bibliography of published reports that describe or summarize various aspects of ground-water quality in Wisconsin is included. (USGS)
