Sustainable Mine Tailings

Offentlig prosjektsammendrag

Minerals and metals play an increasingly central role towards a low carbon future. The total consumption of metals (e.g. Al, Co, Fe, Pb, Li, Mn and Ni) is expected to rise significantly, even with strong emphasis on a circular economy. Mine tailings, however, cause a major waste stream, and pose a risk to people and the environment. Failure of a tailings storage facility will have a catastrophic physical, environmental and societal impact on the surroundings. In the past 3½ years only, eight tailings dam failures of significant scale, e.g Mont Polley, Canada and Bento Rodrigues (Fundao), Brasil, give ample evidence that TSFs are not always safe. After the Fundao failure, the World Bank remarked that "the practice is now significantly greater rate of tailings deposition and more frequent and larger dam raises, undermining critical safety elements on which the original design depends". Over the past 100 years, the causes of tailings dam failures are mainly geotechnical. Of the 221 failures examined by ICOLD (International Committee of Large Dams), all were found to be avoidable. Many legacy tailings sites still pose a risk to society and the environment. There is today a lack in understanding of the behaviour of tailing materials, both physical and chemical, and of their impact on the environment. There is an urgent need for improved practice for the design and management of TSFs and for their safe and sustainable closure. This project is a contribution to solving this urgent problem. The project will dvelop solutions for sustainable mine exploitation over the life cycle of tailings storage facilities, with focus on 1) behaviour of tailings material, 2) modelling and prediction, 3) smart monitoring and 4) risk assessment and management. The result will be a coherent risk reduction strategy, with interaction of observations, analysis, judgement and tools for risk-informed decisions for optimizing design of TSFs from both a cost and a safety points of view.