Geochemistry of ground water in mine drainage problems

From information readily available in the literature, the compositions of mine waters are considered and possible reactions that yield such compositions are examined. Both matter balances and thermodynamic considerations indicate that reactions taking place in the mines probably do not involve significant amounts of dissolved oxygen. The reactions do, however, involve water and coexisting geologic materials (minerals and probably coal if present), which, in the absence of side reactions with carbonates, yield an acidic and strongly reduced solution. In the absence of active mine ventilation, mine water is an anaerobic solution. Major implications of the theoretical model bear on the treatment processes feasible for reducing the effect of acid mine water on surface-water resources.