A modest expansion for the Copper Mountain mill and the development of a new pit will extend the life of the mining
operations. (Photo: Copper Mountain Mining)

When compared to the previous Copper Mountain mine plan, the new plan includes a 102% increase in mineral reserves, a 27% increase in average copper equivalent production to 116 million lb/y over the first 10 years, a 12-year extension in mine life to 26 years, and a decrease in C1 cash costs to $1.87/lb. The new plan outlines a phased approach to the investments. The first phase would be the plant expansion, which requires installation of a third ball mill. The expansion could be completed as early as the first quarter of 2020 and is forecast to cost approximately $25 million.

The second phase would be development of the New Ingerbelle pit, which would require capital investment of about $23 million. Pit development would require about 24 months to complete. The plan is based on mineral reserves only and does not include other resource categories. The company believes that potential exists to increase production further by converting resources to reserves as well as by increasing resources through exploration. New Ingerbelle ore would be trucked to the Copper Mountain mill, using the existing mine equipment fleet.

The mill flowsheet includes primary and secondary crushing, grinding, and sulphide rougher/cleaner flotation. A new 22-ft x 38-ft, 12.6-megawatt (MW) ball mill would be integrated into the existing grinding circuit, which would support the increase in throughput to 45,000 mt/d. The plan assumes startup of the third ball mill in the second quarter of 2020. The new mill would operate as a tertiary grinding circuit, installed after the existing two ball mills, which operate in parallel. The final grind size would be reduced from 225 µm to 150 µm, allowing for higher flotation recoveries.

Metallurgical testing on the New Ingerbelle ore has yielded positive results. Average life-of-mine copper recovery is expected to be 85.5%, approximately 5% higher than current levels processing Copper Mountain mine ore. Using improved recoveries of 85.5% for copper, 69% for gold, and 69% for silver, life-of-mine production is forecast to total 1.895 billion lb of copper, 982,000 oz of gold, and 7.3 million oz of silver.

“The new integrated production plan completely transforms the Copper Mountain operations,” Copper Mountain President and CEO Gil Clausen said. “For minimal capital and minimal risk, we have the potential to realize significant value as we expect to increase our annual production, double total life-of-mine production, extend mine life and decrease unit costs. “These growth projects build upon an already solid operating base, allowing us the potential to increase and advance near-term cash flow.”