Environmental indicators for acid mine drainage: advances in knowledge and challenges ahead

摘要

Environmental indicators are measures to track changes in the quality of the air, water, land and ecological systems. At mine sites, such indicators provide information on conditions and processes that exist or may develop during the life of mine phases and after mine closure. The objectives of this contribution are to review predictive environmental indicators for acid mine drainage (AMD) and to illustrate our advances in knowledge and the challenges ahead.Since the first scientific observations on AMD processes at mine sites hundreds of years ago, we have gained some phenomenal knowledge on indicators and their application in life of mine planning. Yet, today's AMD indicators still have serious limitations, are riddled with uncertainties that are hard to quantify, or only allow predictions that represent the best estimate of what will happen in the future. The time has come to drastically improve our scientific efforts to precisely predict impacts and closure liabilities on all scales.The route to greater confidence in the prediction of AMD processes is not through more sophisticated modelling. Our skills at modelling have run ahead of our understanding of the complex mineralogical, geochemical and microbiological processes leading to AMD, and our ability to test models against real data from the laboratory and the field. Improvements will come from better environmental tests and better understanding of the underlying processes at individual mine sites.