Managing high-density tailings disposal – deposition, water management and closure considerations

Abstract

There has been a growing interest in the surface disposal of high-density tailings in recent years. Such an interest is driven primarily by the need to conduct mining in a sustainable manner by minimising environmental and social impact, conserving water and improving tailings safety. Increasingly, more mines are considering thickened or paste tailings disposal in conjunction with paste tailings backfill to better utilise their infrastructure. Several factors have hindered the wider adoption of high-density surface tailings disposal technology. The ability to predict tailings behaviour in full scale is still relatively limited. There is also little experience in managing a high-density tailings facility under varied climatic conditions. A number of high capacity mines have also had production issues meeting the tailings consistency criterion for deposition leading to major reconfiguration of the disposal system due to poor field performance. Some of these uncertainties are being addressed through laboratory and field research with significant advances being made on our understanding on tailings rheology, transportation, mechanism of deposition and post deposition behaviour change of the tailings.