The Minnie Moore Mine produced about $7 million worth of silver ore between 1881 and 1887. In 1927, the mine was abandoned, buildings were dismantled, and equipment removed. In 1964, Federal Resources Corporation constructed a 250 tons per day flotation mill to reprocess tailings at the Site. Tailings reprocessing took place in 1964 and 1965. The Minnie Moore Mine Site presently consists of the 6-acre tailings pile, as well as the remains of the former mill and shop, and a still intact bunkhouse. The main tailings pile is located just south of the site entrance from Broadford Road. It lies on relatively level ground and rises about 20 feet above the original ground surface. The tailings pile is bordered on the east by Broadford Slough, which runs within five feet of the toe of the tailings pile in some places. Lead concentrations in an exposed 6-acre tailings pile at the Site range from 1,400 to 18,500 parts-per-million (ppm). Elevated concentrations of metals exist in nearby soils, including lead concentrations of 4,300 ppm at the former mill building area. The removal action includes the construction of a permanent clean cover for the tailings pile at the Minnie Moore Mine. Other nearby soils containing lead concentrations of 700 ppm or more will be removed and excavated areas will be backfilled with clean fill.
