The presence of toxic elements such as arsenic, cadmium and lead in mine wastes present an unique challenge to their management and disposal methods, particularly at a time when legislation affecting waste management practices are becoming increasingly stringent, all over the world, owing to a greater public awareness of the environment. The rapid depletion of high grade mineral reserves through centuries of mining is imminent and as such there is an urgent need to develop new cost effective technology which would place an emphasis on the sorting, recycling and reclamation of mine wastes. Micro-organisms are known to have played a key role in the solubilisation, transport, and deposition of metals and minerals. Sulfides will react under appropriate conditions to produce sulfuric acid and dissolved species, responsible for acid mine drainage. Both chemical and biological oxidation mechanisms exist but under optimal conditions of pH and temperature, the bacteria-assisted reaction rates are several order of magnitude greater than the chemical rates. If a microbial leaching process can be developed to include the treatment of sulfide tailings, then the potential for the release of toxic substances is lowered and the local environment protected. The metals extracted from tailings material may provide an additional source of revenue and therefore represent a source of future raw-materials
