Thompson Creek Commissioning Mount Milligan
First ore feed to the plant occurred in mid-August, and concentrate production was expected to begin soon thereafter. All of the concentrator grinding and flotation circuits were expected to be operational in September. Commercial production was scheduled to begin in December, followed by a 12-month ramp-up to full design production and recovery.
Mount Milligan is expected to produce an average of 89 million lb/y of copper and 262,000 oz/y of gold in concentrate during its first six years of operation. Life-of-mine production over a mine life of 22 years is planned at about 81 million lb/y of copper and 194,000 oz/y of gold in concentrate.
Mount Milligan will mine 60,000 mt/d of ore from two low-grade copper orebodies, using conventional truck-and-shovel methods. Proven and probable reserves stand at 482 million metric tons (mt), averaging 0.2% copper and 0.39 g/mt gold and containing 2.12 million lb of copper and 6.02 million oz of gold.
The life-of-mine strip ratio is 0.84:1.
The 60,000-mt/d Mount Milligan processing plant utilizes conventional crushing, grinding, and rougher and cleaner flotation to produce a gold-rich copper concentrate. The overall design philosophy was to select large equipment in order to maintain a simple, conventional, single-line flowsheet.
Construction at Mount Milligan began in mid-2010. Through June 30, Thompson Creek spending on the project totaled C$1.41 billion, and total capital spending is expected to reach C$1.57 billion at project completion.