Mine Waste Characterization
Thousands of historical mine-waste piles are present on inactive metal-mining sites, some of which are on federal lands and have been abandoned. Assessment of metal mobility, acid-drainage production, and toxic effects from the weathering of historical mine-waste piles is an area of growing need as the environmental effects of inactive mine-waste sites across the country are being evaluated and mitigated.
The U.S. Geological Survey Mine Waste Characterization Project has taken a multidisciplinary approach to assemble, develop, and refine methods and tools for characterizing and screening weathered solid-mine wastes. Researchers from a variety of disciplines, including geophysics, geochemistry analytical chemistry, geology, mineralogy, remote sensing, and spatial modeling, have worked together at metal mining waste sites in Colorado and New Mexico to develop an integrated "toolkit" for the rapid screening and characterization of historical mine-waste piles. Detailed studies have been conducted at eight main mine-dump sites (six are located in Colorado), representing both igneous-hosted and carbonate-hosted polymetallic deposits, to examine the influence of carbonate materials. Two other sites are arid analog mine-waste piles in southwestern New Mexico chosen to examined the influence of climate. Tools developed from this work can be used in ranking and prioritizing historical mine-waste piles.