Operators monitor video displays in the control room at Goldcorp’s Musselwhite mine in Canada. The company plans to spend about $90
million on improvements to reduce the mine’s haulage costs. (Photo: Goldcorp)

At Peñasquito, the company is investing approximately $420 million in a Pyrite Leach Project (PLP) to increase overall gold and silver recovery by treating zinc tailings before discharge to the tailings storage facility. At Musselwhite, the company is investing approximately $90 million to develop an underground winze and associated infrastructure that will result in reduced reliance on high-cost truck haulage.

The Peñasquito PLP is expected to recover approximately 40% of the gold and 48% of the silver currently reporting to tailings. The project will add annual incremental production in the range of 100,000 oz to 140,000 oz of gold and 4 million oz to 6 million oz of silver. Commercial production is expected in the first quarter of 2019.

The Peñasquito mine produced 860,300 oz of gold in 2015. PLP operating costs are expected to be approximately $1.75/mt. The project will have a minimal impact on the site water balance and will not require upgrades to the water supply as the PLP plant will recirculate existing plant processing water.

At Musselwhite, mining currently takes place at a depth of more than 1,000 m under Lake Opapimiskan, and the truck haulage distance is 7.5 km to the underground crusher on the 400-m level. The haul truck fl eet has increased to 17 haul trucks. A more economical and practical means of transporting ore is required; because the ventilation system cannot support the larger haul truck fl eet that would be required to extend mine life.

The investment project now under way at Musselwhite will enable hoisting of ore through a winze, significantly reducing uphill truck haulage and leading to improved energy efficiency, reduced ventilation requirements, reduced mining costs, enhanced production profile, and potential to extend mine life through exploration success.

Following completion of the winze, scheduled for the first quarter of 2019, incremental added production of approximately 20% is anticipated, and operating costs are expected to be reduced by approximately 10% for the life of the mine. The Musselwhite mine produced 270,300 oz of gold in 2015.