Sustainable Management of Thickened Tailings in Chile and Peru: A Review of Practical Experience and Socio-Environmental Acceptance

The “Thickened Tailings Disposal” (TTD) technology produces a high density mine waste that allows for the storage of this material without the need to manage large slurry tailings storage facilities (TSFs) and large dams. TTD has been applied considering site specific conditions of Chile and Peru, such as extreme climatic conditions, seismic risks, water scarcity, community demands, and environmental constraints. This review highlights the contribution of several experiences in Chile and Peru, which have chosen TTD technology for reduction of negative environmental impacts, mainly focusing on the following issues: (i) increase of tailings water recovery, (ii) reduction of TSFs footprint (impacted areas), (iii) decrease the risk of physical instability, avoiding the construction of high dams, and (iv) decrease of TSFs seepages. Finally, the article describes the advantages (benefits) and disadvantages (aspects to improve) of TTD, where nowadays a high degree of dewatering of tailings is seen as a safe option, considering the occurrence of some TSF dam failures recently worldwide, which has resulted in severe environmental pollution. A better environmental perception about TTD of authorities and communities, considering that this technology allows to satisfy the needs of stable and safe TSFs, make the TTD be more acceptable, popular and one of the best available technologies (BATs) for operations with mine tailings.