Push Back Design in Two-element Deposits Incorporating Grade Uncertainty (RESEARCH NOTE)


Department of Mining and Materials, Tarbiat Modares University, Tehran, Iran


Push back design as a complex task, is one of the major steps in the open pit mines planning. Push backs can be generated by varying economic factors such as commodity price, mining cost, processing cost, etc. Another important issue in generating push backs is grade uncertainty, which can cause the problem be more complex. Conventional methods of push back design ignore grade uncertainty. To overcome this, “Grade Parameterization using Variance Algorithm” (GPVA) can be implemented. In this paper, an attempt was made to utilize GPVA in a hypothetical two-element deposit with the aim of minimization grade uncertainty effect on push backs design. Finally, the same example was solved using Whittle algorithm, the results indicate the superiority of the GPVA.


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