Department of Earth Sciences, University of Bristol
Prof. D.M. Sherman
Lecture 11: Acid Mine Drainage
Acid mine drainage is a common problem throughout the world.
Exposure of pyrite (FeS2) to the atmosphere results in oxidation
to yield dissolved Fe2+ and H2SO4.
Acidophillic, chemolithoautotrophic bacteria oxidize Fe2+
to Fe3+ which, in turn, rapidly oxidizes pyrite. In addition to
acidifying rivers and lakes, AMD also releases heavy metals such as Zn and Cd.
You should be able to outline:
the overall reactions for pyrite oxidation.
the consequences of AMD and the geochemical controls on heavy metal concentrations.