Pretium Resources has retained Wardrop, a Tetra Tech company, to prepare a feasibility study of its Brucejack gold-silver project in northwestern British Columbia. Snowden Mining Industry Consultants will provide an underground resource model for the high-grade gold and silver resources identified to date in the Valley of the Kings and West zones of the project. The feasibility study is slated for completion by year-end 2012.
A 24,000-m drill program is in progress at the Valley of the Kings zone, focused on mineralization to be mined in the first 12 years of operation as contemplated in the updated project preliminary economic assessment (PEA) dated February 20, 2012. Drill spacing is being tightened to move inferred mineral resources to measured and indicated. Inferred mineral resources at the Valley of the Kings currently total 3.23 million oz of gold at an average grade of 26.89 g/mt.
A permit application has been filed to access the Valley of the Kings underground by driving an exploration decline from the 1,330-m level of the existing West zone underground workings. The West zone has been dewatered past the 1,330-m level, and a surveying and geotechnical mapping program has been completed. A 3,500-m geotechnical surface drill program is under way to confirm ground conditions between the Valley of the Kings and the West zones.
The updated PEA estimates total production of 6.9 million oz of gold and 17 million oz of silver over a mine life of 24 years. Base case average annual production is 325,000 oz of gold over the first 12 years and 287,000 oz of gold over the life of mine. Initial capital cost is estimated at $436.3 million, including contingencies, and mine operating costs are estimated at C$170.90/mt milled over the life of the mine.
Underground mining is planned at a rate of 1,500 mt/d, with 11.8 million mt to be mined from the two zones at an average mill feed grade of 18.9 g/mt gold and 59.3 g/mt silver. Gold-silver doré will be produced using a combination of conventional bulk sulphideflotation, gravity concentration and cyanidation, with gold and silver recovery by the Merrill-Crowe process.