Feasibility Study Supports Hardrock Project


Centerra Gold and Premier Gold Mines have reported positive results from a feasibility study for their Hardrock gold project in Geraldton, Ontario, approximately 250 km northeast of Thunder Bay. The study supports development of an open-pit mine and processing facilities that would produce an average of 288,000 oz/y of gold over a mine life of 14.5 years. Mill throughput is planned at 27,000 mt/d.

During its first four full years of operation, Hardrock would produce an estimated 356,000 oz/y from a total of 38 million mt milled at an average head grade of 1.27 g/mt gold. Initial capital costs to develop the Hardrock project are estimated at C$1.25 billion, including a contingency of C$131 million. Total life-of-mine sustaining capital is estimated at C$257 million, and operating costs are estimated at C$20.95/mt of ore processed. Average all-in sustaining cost of gold production is estimated at US$600/oz.

The Hardrock project’s open-pit probable mineral reserve stands at 4.7 million oz of gold contained in 141.7 million mt at an average gold grade of 1.02 g/mt, using a cut-off grade of 0.33 g/mt and including 17.3% mining dilution. The feasibility study includes mineral reserves for the open-pit Hardrock deposit only. There may be opportunities to improve the life-of-mine average grade by processing higher-grade material from other deposits held by the Centerra/Premier partnership. These opportunities are currently being reviewed; however, there are no assurances that these additional deposits will be developed.

The Hardrock feasibility study is based on conventional open-pit mining, with 10-m benches. The open-pit operation is planned to be owner operated, with outsourcing of certain support activities. The processing flowsheet includes crushing, grinding, pre-leach thickening, a leach and carbon-in-pulp circuit, cyanide destruction and tailings disposal, carbon elution and electrowinning, carbon regeneration, and a gold refinery.

Existing grid power is insufficient for powering the Hardrock processing facilities and associated infrastructure. A 65-megawatt (MW), natural gas-fired power plant would be constructed to supply power, including a natural gas pipeline originating from the existing TransCanada PipeLines mainline pipeline.

The Hardrock feasibility study was prepared by G Mining Services in collaboration with third-party consulting firms. The Centerra/Premier partnership has not made a development decision on the project. Work going forward will include advancement of permitting and First Nation discussions.


As featured in Womp 2016 Vol 12 - www.womp-int.com