This report details the results of a study conducted by University of Colorado researchers for the Coal Creek Watershed Coalition on the source of metals in the Coal Creek watershed during early spring flow. Coal Creek is the main water supply for the Town of Crested Butte in Gunnison County, Colorado.

Metal-mining associated wastes in the Lefthand Creek watershed in Boulder County, Colorado have been implicated as a major source of stream water contamination due to acid generation and toxic metal solubility. This watershed hosts hundreds of now inactive mine openings and dozens of sites of former ore milling. No complete analysis of mine sites or their environmental impacts exists to date. This report documents research and analysis of the sources,...