KEYNOTE: MINE WASTES: PAST, PRESENT, FUTURE

Since the dawn of civilization, humankind has been extracting metals and minerals for the production of goods, energy and buildings. These activities have created great wealth, but they have also produced huge quantities of solid and liquid wastes, known collectively as ‘mine wastes’. Even today, tens to hundreds of tonnes of waste are generated for every tonne of ore mined. This is a problem of global significance: almost every country in the world has or has had a mining industry and therefore, a legacy of mine waste. Mine wastes often contain high concentrations of toxic elements and compounds that can have severe effects on ecosystems and humans. For example, waters draining waste rock piles or tailings impoundments may threaten ecosystems or drinking water supplies, and windblown dust from dry, unvegetated mine wastes may be inhaled or orally ingested. Over the past ten to fifteen years, new and novel geochemical, mineralogical, microbiological and toxicological techniques have lead to a much better understanding of the character, weathering mechanisms, long-term stability, ecotoxicology and remediation of mine wastes. This presentation will report on these current findings and highlight new frontiers for mine waste research.