Location theory applied to optimize the position of road exit(s) in open pit mining (case study)

Abstract

Roads are one of the more important aspects of open pit mines’ planning and design. Practical pit must include haulage road which influences the pit slope, stripping ratio, and consequently the reserve quantity. The first question must be answered when sitting the road in the pit wall is “where is the road exit(s) on the pit wall?” In this paper, we have presented a mathematical model to optimize the road exit(s) and so the transportation cost. This model gives the most optimum and practical location of the road exit(s) on the pit perimeter which has the minimum transportation cost. The road position in open pit wall was considered as a function of the volume of material which must be transported from the pit (mine) to different destinations such as waste dump, stock pile, mill, and leach dump according to cut-off grade strategy. As a case study, the model was implemented in a copper mine in Iran, and the optimum position of the road in the pit wall was determined. In cases that the optimum point is not available or if more than one exit point would be needed, using of iso-cost lines was explained in the paper to find the practical solution.