Prediction of Acid Mine Drainage Formation

The end-of-pipe approach to treat acid mine drainage (AMD) is costly and environmentally unacceptable. The use of predictive tools provides a proactive and sustainable approach to prevent or minimise AMD formation. Therefore, the mine waste materials should be characterised to predict the potential, rate and timing of AMD formation, and likely leachate composition in order to proactively facilitate the development of waste control and disposal strategies where AMD risk is evident. This chapter describes the application of the acid-base accounting (ABA) method, other geochemical static tests, the humidity cell and leach column kinetic tests that are widely used to predict the potential for AMD formation. The prediction data helps to identify waste materials that are potentially acid forming (PAF) (with high risk of AMD), acid consuming (ACM) and non-acid forming (NAF). Such classification criteria can facilitate the use of source control technologies to mitigate AMD formation and avoid its huge remediation costs.