EXPLORATION ’95 — Westmin, Cathedral extend Porcher Island

After failing, by year-end, to reach a decision regarding mine development at the Porcher Island gold property southwest of Prince Rupert, B.C., Westmin Resources (TSE) obtained a 6-month extension from its project partner.

Westmin is considering approaching third parties to act as project operator so that its mining and resource staff would not be required to stay on the site.

“We are happy to do the processing,” says Westmin’s Bruce McKnight, adding that the extra tonnage will increase the efficiency of Westmin’s mill at the Premier gold project in Stewart, B.C.

Company geologist Paul Lhotka says the current agreement (amended to include the extension) between Westmin and Cathedral Gold (TSE), which owns the Porcher Island property, is still “in good standing.” Westmin can earn a half interest in the past producer (starting in the 1930s) by completing a feasibility study and making a development decision.

Should Westmin proceed with mine development, Cathedral will have 60 days to decide whether to participate in a 50-50 joint venture or reduce its interest to a 25% net profit royalty and 3% net smelter return royalty. The feasibility study is already complete, but it remains an internal document. Lhotka says the decision to proceed was stalled last year pending clarification of certain permitting requirements.

“We have just received the terms of reference for the mine application and they are favorable,” he says. “We had some initial concerns, especially one potentially significant item which was cents ultimately resolved].” The concern was focused on a small amount of metal and acid drainage from the Surf Point mine (an old, unrelated working) at one corner of the Porcher Island property. Historically, the seepage had been dealt with naturally in a swamp area, with no impact on the downstream fishery. Under the original terms of reference, as set out by Environment Canada, Westmin was required to treat this effluent material at a cost that would have detracted from the economic viability of the project.

Lhotka says the company has, with the help of the provincial government, succeeded in its attempts to have that condition removed.

The feasibility study looked at initiating production with a bulk sample to test continuity, grade and the ability to sort the ore to improve the grade. As well, the company is looking to develop additional reserves. “We are thinking of about l0,000 tons cents as a bulk sample],” McKnight says. Following the bulk-sampling, the mine would move immediately into full production. The strategy is to obtain all permitting first, so that the company will not have to bear the cost of two startups.

The plan calls for the mining of 150,000 tons, and sorting it to an “ore weight” of 90,000 tons. This would be shipped from Porcher Island — 215 km by barge — to Westmin’s mill at Stewart.

Proceeding with the project means Westmin would have to construct a flotation circuit at the Premier mill to float off the gold concentrate. The company would then ship from Stewart aboard vessels already calling at port to pick up Eskay Creek concentrate and bring it to smelters in Japan. An unusual characteristic of the ore at the underground operation is that, after blasting, the fines contain most of the gold; the larger waste rock has little precious metal. In the past, a grizzly was used to sort the material by size, and Lhotka says Wetmin will probably follow the same procedure. This will reduce the dilution by waste rock and, therefore, the amount of tonnage shipped and milled. Previous operators found that this procedure raised the gold content to 0.5 from 0.3 oz. gold per ton.

The size of the opening in the grizzly is 6 inches in diameter, and the sort will take as waste rock all material exceeding that size; the material of lesser diameter will be the gold-bearing ore. The waste material, a hard granite, may prove salable, Lhotka says; the city of Prince Rupert, with no gravel quarries in its area, is looking at using it for road construction work.

— The author is a freelance writer based in Vancouver, B.C.