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Chemical and Microbiological Characteristics of Mineral Spoils and Drainage Waters at Abandoned Coal and Metal Mines

Mining is a long-established human activity. Abandonedmines, tailings, and mine spoils may have considerable impacton neighboring environments long after the sites are abandoned. Of greatest concern are derelict mines and wastes that generateacidic discharge waters that are enriched with iron and othermetals and metalloids. The chemistry and microbiology of thesesites are intricately intertwined. Whilst some indigenousmicroorganisms are responsible for accelerating sulfide mineraloxidation, thereby generating acidity and mobilizing metals,others catalyze reductive processes that essentially reversethese reactions and thereby ameliorate polluted mine waters.This article reviews current knowledge on the chemistry and microbiology of abandoned coal and metal mines, mine spoils and tailings.