Pit Design by Computer at Gaspe Copper Mines, Limited

CIM Bulletin, 1971

F. J. GAUTHIER, Chief Mine Engineer, Gaspe Copper Mines, Limited, Murdochville, Quebec; R. G. GRAY, Senior Technical Analyst, Noranda Mines Limited, Toronto, Ontario

The possibilities of expanding the production rate from the Copper Mountain Mine have been examined using computer programs for analysing a complete range of data, beginning with the diamond drill assays and embracing all steps up to the final rates of return. Programs have been developed to calculate the mineralization inventory file, a matrix of blocks containing the grade and the type of mineralization estimated for each block. Given the topography, prices of metals and costs, the pit limits are optimized using a three-dimensional technique. Within the pit, ore reserves at any cutoff can be calculated. Mining of the pit is then simulated using an interactive production scheduling program on a timesharing computer. The annual tonnage and grade figures from the production schedule are input to a financial analysis program, where the present value and the rate of return are calculated at various metal prices. The expansion possibilities can be run through the programs with their respective costs, and evaluated using the rate of return on the marginal cash flow compared to the additional capital expenditure.
Keywords: copper, Copper Mountain deposit, molybdenum, open pit, ore, parallelepiped, Grade, Mine, Mines, Ore, Ores, Pits