Cumberland drills Nunavut gold — Goose Island deposit deemed amenable to open-pit mining

Drilling by Cumberland Resources (CBD-T) at its wholly owned Meadowbank gold property in Nunavut is expanding one deposit and upgrading another.

Situated north of Baker Lake, the project consists of four shallow gold deposits along a north-south trend: North Portage (1.4 million tonnes); Third Portage (5.6 million tonnes); Bay Zone (735,000 tonnes); and Goose Island (1.1 million tonnes).

Prior to the recent drilling, resources at Meadowbank stood at 8.8 million tonnes grading 6.15 grams gold per tonne, equivalent to 1.7 million contained oz. gold. Uncut, the grade is 7.04 grams gold, which raises the number of contained ounces to 2 million.

So far this year, Cumberland has drilled 61 holes totalling 6,000 metres. Results have been reported from 12 delineation holes drilled on the northwestern portion of Third Portage and seven infill holes on Goose Island.

Previously, Cumberland had drilled only a handful of holes across the northwestern portion of Third Portage, which lies beneath a 200-metre-wide bay in Second Portage Lake. These holes averaged 4.3 grams gold over a width of 3 metres, but Cumberland geologists believed more drilling would produce better results, and, with a proposed starter pit encroaching on the area from the south, the company needed more data before deciding whether to extend the pit into the northwest.

The latest drill results from Third Portage indicate higher grades and tonnages at shallow depths, with highlights as follows:

• 13.9 metres (from 29 metres) grading 5 grams gold per tonne in hole 353;
• 5.8 metres (from 53 metres) of 9.25 grams in hole 354;
• 14 metres (from 22 metres) of 6.1 grams in hole 342;
• 4.2 metres (from 35 metres) of 8.35 grams in hole 337; and
• 15.8 metres (from 349 metres) of 5.32 grams in hole 349.

“We’re very pleased with these results and believe we can certainly add ounces up in that area,” says Kerry Curtis, Cumberland’s senior vice-president. “It’s shallow mineralization and it looks as if it can be included in year two or year three of open-pit mining at Third Portage.”

At Goose Island, infill drilling has targeted the near-surface, higher-grade portion of the deposit, where total resources are estimated to be 1.1 million tonnes grading 9.33 grams gold, equivalent to 333,900 contained ounces.

Highlights from recent drilling at Goose Island include:

• 23.8 metres (from 84 metres) grading 5.27 grams gold in hole 324;
• 4.7 metres (from 140 metres) of 27.43 grams and 4.6 metres (from 155 metres) of 35.03 grams in hole 325; and
• 8.3 metres (from 148 metres) of 4.33 grams in hole 332.

The Goose Island deposit had been considered for its underground potential, though an ongoing prefeasibility study now indicates that a portion of the deposit is amenable to open-pit mining.

“The engineers tell us it [open-pit mining] is more feasible than we thought,” says Curtis. “There’s a wide plunge in the upper 100 metres of the deposit that works in our favour, and there’s a good high-grade volume close to surface.”

Open-pit mining of these two recently drilled areas would require the construction of two dykes: one across the north end of the bay at Third Portage, and a second that would encapsulate Goose Island.

While the lakes in the Meadowbank project area are wide, they are also shallow, particularly between Goose Island and Third Portage, where water depths are only 2-3 metres.

“It’s not a big deal on the technical side,” says Curtis. “We’re looking at a case much like Diavik [the proposed diamond mine near Lac de Gras, N.W.T.], where you begin open-pit mining at Third Portage — it comes to surface and there are a few good years of open-pit mining there before we have to incur into any lake. The waste that’s on top of the deposit could be removed and classified as non-acid-generating waste, which could be used to build the water-retention dykes.

“The attractive thing from an environmental perspective is that after mining is completed, these water-retention dykes can be completely or partially removed and the lake can slowly build back and cover all that area.”

Curtis goes on to explain that the structure between Goose Island and Third Portage is still not well-understood, though Goose Island is known to plunge steeply to the south, whereas Third Portage plunges shallowly in the same direction. Near-surface drilling carried out between the two deposits has intersected the same stratigraphy associated with both, with the notable exception of the gold-bearing iron formation.

“That’s not to say that if we went deeper, say 200 to 300 metres downdip, we wouldn’t find something,” says Curtis. “One hole drilled last year in between Goose and Third Portage, on the south end of the Bay zone, intersected roughly 8 grams over 4 metres at a vertical depth of about 250 metres. That hole intrigues us; it certainly tells us there’s more exploration work to be done.”

Asked about the North Portage deposit, Curtis comments: “North Portage is probably the lesser known of all the deposits. Part of the goal of the prefeasibility study is to ascertain how important North Portage is, or could be, and how much exploration effort should be directed toward that area.”

Results from the remaining 41 drill holes will be announced as they are received, beginning in late June.

Early this month, at the annual meeting, shareholders approved a rights protection plan, though management says it is unaware of any pending or threatening takeover bid for the company.

Meanwhile, at the Meliadine West project near Rankin Inlet in Nunavut, Cumberland and its joint-venture partners have completed half of a 20,000-metre program of infill drilling in the Tiriruniak zone; the drilling is being spaced on 50-metre centres to a depth of 200 metres.

Assay results from the first six of 59 holes are confirming previous grades and thicknesses. Highlights include:

• 17 metres (from 321 metres) grading 4.1 grams gold in hole 280;
• 7.2 metres (from 113 metres) of 9.3 grams in hole 288;
• 16.3 metres (from 182 metres) of 3.9 grams in hole 309; and
• 29.5 metres (from 63 metres) of 4.3 grams gold in hole 340.

Cumberland and Comaplex Minerals (cmf-t) each hold a 22% carried interest in Meliadine West, whereas operator WMC International, a subsidiary of Australia’s Western Mining Corp. (WMC-N), has 56% plus an option to acquire another 2% from each of its partners.

Resources at Meliadine West are pegged at 23.7 million tonnes grading 8.5 grams gold, equivalent to 6.5 million contained ounces. Mineralization is divided among four zones: Tiriruniak, F, Pump and Wolf.