Optimising the mine production scheduling accounting for stockpiling and investment decisions under geological uncertainty

This paper presents an approach to optimise the long-term production scheduling of an open pit mine with multiple processing streams, while accounting for investment decisions under mineral supply uncertainty. The solution approach consists of first solving the linear relaxation using an extension of the Bienstock-Zuckerberg algorithm to the stochastic optimisation. Then, a rounding heuristic based on the topological sorting is applied, followed by a parallel multi-neighbourhood Tabu search. The proposed method is applied to a multi-product open pit mine deposit, with the possibility of investing in new shovels, trucks or crushers to increase related capacities.