Optimisation of production planning for an innovative hybrid underground mining method

Conventional underground mining methods rely on extracting a large amount of ore rock from its original place and moving it to surface. An innovative idea of in mine recovery (IMR) has been recently presented by Mining3 to minimise rock movements by recovering low grade ore deposit using in-situ leaching concept. In this paper, the added value of the hybridisation of IMR and a conventional mining method is evaluated through a strategic resource-constrained planning model. The proposed integer programming model simultaneously considers orebody characteristics, mining and leaching capacities, processing requirements and associated mining and processing costs. Results of solving the proposed model for a small-scale orebody, demonstrate that integrating IMR into a conventional mining operation can significantly improve the net present values of the project by recovering the low grade part of the orebody usually left as the waste rock in conventional mining methods.