Study models potential 17-year mine life for Turnagain

Vancouver — Hard Creek Nickel (HNC-V, HNCKF-O) has received the preliminary assessment study for its Turnagain nickel deposit in northern British Columbia.

The report, conducted by engineering firm AMEC, reviews various factors in advancing the project towards production including resources, geology, metallurgy, infrastructure and preliminary economics.

A base-case scenario modelled a 50,000-tonne-per-day open-pit operation mining about 302 million tonnes of ore averaging 0.174% nickel sulphide, 0.014% cobalt and 0.027% copper over a potential 17-year mine life with a 0.63:1 stripping ratio. Operations would focus on material with a 0.14% nickel sulphide cutoff grade in the first six years, dropping to a 0.095% nickel sulphide cutoff for the remaining mine life. Material between 0.095% and 0.14% nickel sulphide mined in the first six years will be stockpiled for later processing.

At the base case (0.095% nickel sulphide cutoff), Turnagain contains a measured and indicated resource of 184 million tonnes at 0.17% nickel sulphide plus an additional 286 million inferred tonnes grading 0.16% nickel sulphide, all mostly contained within the Horsetrail zone.

Plans call for ore to be run through a crushing-milling circuit then concentrated through an on-site flotation circuit. The study also reviews a hydrometallurgical process whereby the concentrate would be reground, pressure oxidized in an autoclave and then leached to produce nickel, cobalt and copper precipitates.

Metallurgical recoveries for nickel, cobalt and copper from the flotation concentrator circuit are estimated at 75-77.5%, 65% and 50% respectively. The hydrometallurgical process is expected to recover about 95% of the nickel, cobalt and copper in the concentrate. Over the life of the mine, total estimated metals recovered are estimated at 378,223 tonnes (833 million lbs.) nickel, 26,124 tonnes (57.5 million lbs.) cobalt and 38,755 tonnes (85.4 million lbs.) copper.

Capital spending is estimated at $867 million with about $495 million of that for direct infrastructure costs (power, road, plant, etc.). Total mine-site operating costs are estimated at around $9.50 per tonne or about US$3.45 per lb. nickel over the mine life.

Using metal prices of US$5.25 per lb. nickel, US$10 per lb. cobalt and US$1.10 per lb. nickel and a 10% discount rate, the project has a net present value of $85 million. Based on these figures, a 12% rate of return is projected.

Extension of a provincial power grid along the Highway 37 corridor to Dease Lake would significantly improve the viability of development at Turnagain. AMEC’s report recommends further exploration drilling, mine engineering and metallurgical work before proceeding to prefeasibility.

Hard Creek also recently engaged a Beijing-based financial advisory firm for representation in any prospective business alliances in China.