Determination of Underground Mineable Reserve with Regard to Metal Price Uncertainty and Sustainable Development

Abstract

Mineable reserve determination is one of the important parameters in economic profitability and the safety of underground mining production. The fluctuations in the metal prices will lead to a change in the cut-off grade, and as a result, the mine layout and mineable reserve will change. On the other hand, changing the underground mine layouts will also change the economic, social and environmental impacts (sustainable development parameters). Therefore, ignoring metal price uncertainty lead to a non-optimal design. The aim of this paper is the determination of underground mineable reserve regarding metal price uncertainty and sustainable development. Metal price uncertainty is simulated with Monte Carlo technique and the most important sustainable development indicators are entered in the cut-off grade formula. In this way, four types of cut-off grades were defined. Based on these cut-offs four types of mine layouts are obtained. Basic, simulated, green and sustainable mine layout. Basic Mine layout is that obtained by normal design, simulated mine layout considers just metal price uncertainty, green mine layout considers metal price uncertainty and environmental criteria and sustainable mine layout considers metal price uncertainty and environmental and social criteria. Results from the use of this methodology in a hypothetical gold mine show that the mineable reserve in sustainable mine layout is 17 percent greater than the basic mine layout. Regarding the result, with this methodology in addition to consideration of metal price uncertainty and sustainable development criteria, the more mineable reserve will be achieved. For future research, in addition to using other price simulation methods; it is suggested that other indicators of sustainable development be included in determining the underground mine layout.