Drinking-Water Quality and Variations in Water Levels in the Fractured Crystalline-Rock Aquifer, West-Central Jefferson County, Colorado

摘要

In parts of the area, water for domestic use obtained from the fractured crystalline-rock aquifer contained excessive concentrations of dissolved fluoride, dissolved nitrite plus nitrate, dissolved solids, dissolved iron, dissolved manganese, dissolved zinc, coliform bacteria, gross alpha radiation, and gross beta radiation. Based on water-quality analyses from 26 wells located in small urbanized areas, water from 21 of the wells contained excessive concentrations of one or more constituents. Local variations in concentrations of 15 chemical constituents, specific conductance, and water temperature were statistically significant. Depths to water in 11 non-pumping wells ranged from 1 to 15 feet annually. Three-year trends in water-level changes in 6 of the 11 wells indicated a decrease in stored water in the aquifer.