Some of the most publicized environmental disasters are associated with the mining industry. These disasters are attributed to both natural and miningrelated causes. Acid drainage, for example, formed by rainwater or snowmelt in contact with mineral deposits can damage nearby ecosystems by polluting streams and destroying wildlife. The mining and processing of ores, however, may accentuate and accelerate the natural processes.

Long- and Short-Term Impacts of Mining in the Environment

On a long-term basis, mining can increase the acidity of water in streams; cause increased sediment loads, some of which may be metal-laden, in drainage basins; initiate dust with windborne pathogens; and cause the release of toxic chemicals, some contained in exposed ore bodies and waste rock piles and some derived from ore-processing reactions. Contaminants containing such toxic chemicals as cyanide and lead may be transported far from a mining site by...