Stabilisation of Soft Tailings: Practice and Experience

Abstract

Abstract Environmentally acceptable reclamation solutions for the decommissioned tailings ponds can be achieved by integrating the tailings deposits into the landscape either by turning the tailings pond/deposit into a lake and maintaining a permanent water cover over the deposit or by stabilisation of the deposits as a “dry” landform. Conceptually, the dry landscape reclamation involves three remedial steps: 1) Placement of an interim cover on the tailings surface to provide the consolidation load and create a stable working platform. 2) Building of a surface contour providing suitable run off conditions for the surface water. 3) Capping the surface with a final cover to control infiltration into the tailings. For reliable predictions of consolidation, proper sequencing of remedial steps/measures and cost efficient reclamation of soft tailings it is necessary to use Non Linear Finite Strain (NLFS) codes. The advantage of the NLFS program system Consol2D is that it allows the reconstruction of the history of the tailings discharge, the evaluation of the material parameters, the calculation of settlement in inhomogeneous deposits, the 3D quantification of the settlement trough and the evaluation of the drainage effect of the vertical drains.