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Acid rock drainage (ARD) is produced by the oxidation of sulfide minerals, chiefly iron pyrite or iron disulfide (FeS2). This is a natural chemical reaction which can proceed when minerals are exposed to air and water. Acidic drainage is found around the world both as a result of naturally occurring processes and activities associated with land disturbances, such as mining where acid-forming minerals are exposed at the surface of the earth. These acidic conditions can cause metals in geologic materials to dissolve, which can lead to impairment of water quality and soils when acidic and used by terrestrial or aquatic organisms.

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Charles Afriyie-Debrah, BSc. (Hons) Chemistry and MSc. (Hons) Environmental Science all from the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. He is currently the Biosafety Officer of the Council for Scientific and Industrial Research-Crops Research Institute-Kumasi, Ghana.

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