The quantification of grade uncertainty, and associated risk, and their influence on pit optimisation for the Sadiola deep sulphide prefeasability project

[摘要] In order to quantify the uncertainty in the grade estimate for the Sadiola DeepSulphide Prefeasibility Project a conditional simulation model was generatedusing Direct Block Simulation methodology. Compared to conventionalSequential Gaussian Simulation, the Direct Block Simulation algorithm produceda reliable model in significantly less time, lending its application to a productionenvironment.Through application of a mining transfer function, risk pits were generated forcomparison with the Deep Sulphide Prefeasibility pit. The results of this studyrevealed that the prefeasibility pit is optimal at the applied gold price and costparameters, and that the risk of not achieving the project grade profile is low.Should the gold price increase, or the operating costs of the project decreasesignificantly, the Deep Sulphide reserve tonnage would realise significant upsidepotential.The potential for using the simulation model coefficient of variation to improve theclassification of the resource has been highlighted. This exercise could allowsignificant saving of feasibility drilling capital.

[发布机构] University of the Witwatersrand