Acid mine drainage is a serious and chronic environmental problem of
mining. This paper discusses the factors affecting the rate of acid
generation by mine rocks and illustrates the relevance of these factors to
the mines of the Northern Territory, Australia. The factors may be divided into two groups: internal factors and
external factors. The first group covers characteristics of ores, mine
waste rocks, tailings, etc and the second group covers surrounding
conditions. The latter is further divided into four sub-groups, viz
surrounding temperature and pressure, chemical conditions (ferrous/ferric
adsorption ratio, total iron concentration, oxygen concentration and pH),
surrounding biological conditions and mechanical conditions. Special
attention is given to the surrounding P-T conditions, especially water
partial pressure, and its relevance to the Northern Territory mines.