Despite awkward location Inco on schedule at new mine

As northwestern Quebec was blanketed this week in yet another layer of snow, Inco Gold could well have re-named its first gold producer “frozen” pond instead of Golden Pond.

A severe snow storm hampered the travelling plans of at least three parties who attempted to reach the mine site. Otherwise the Toronto-based subsidiary of Inco Ltd. is proceeding on shedule toward a late- August start up date at its Casa- Berardi mine, The Northern Miner can report after visiting the new facility.

With a stockpile of 40,000 tons of ore waiting on surface, Inco will pour the first gold bar from its Golden Pond project in late August.

Located 100 km north of La Sarre, Que., the project is the first of the Casa Berardi gold plays with sufficient reserves to sustain a mining operation. It is also an important part of Inco’s plan to produce 115,000 oz from at least three gold mines by 1991. The others are located in Brazil and Montana.

After seven years of exploration and development, Golden Pond is posing only one major headache for manager Aurelio Petracchi and his team of geologists and operating personnel. Round trip

The mine is too close to La Sarre to justify building living accommodation for the 145 miners and engineers who will work at the project. So when production begins next February, the employees will face a 200 km round trip along an unpaved logging road from La Sarre to the camp as part of their daily routine. The company has lined up 12 passenger vans for the purpose.

However, Inco will save its employees some discomfort by operating a tight schedule which calls for two 10-hour shifts working four days per week.

After spending $74 million to build a 1,250-tonne-per-day carbon and leach mill and additional infrastructure facilities including power lines and crusher, a five-month pre- production phase will begin Sept 1.

When the operation is put into a full production mode in Feb 1989, Inco will use mechanized cut and fill methods with ramp access to mine 65,000 oz annually from the West zone.

“The irregular nature of the ore indicates to us that the cut and fill method is needed to optimize extraction and recovery,” said Petracchi.

Located on the Casa Berardi Main Break beneath thick overburden which varies from 10 m to 25 m in some areas, the disseminated gold deposits appear to lie between surface and a depth of 300 m.

“So far, our deepest intersection on the East Zone was encountered at the 350 m level,” said Petracchi. Considered Cheap

At a mine operating cost of less than $200(US) per oz, the project is considered cheap relative to other Canadian gold producers. However, as The Northern Miner noted during underground visit, Golden Pond has a number of other factors going for it.

Since the feasibility and projected 10-year life of the operation is predicated on the East Zone, where proven reserves stand at 2.8 million tons grading 0.25 oz per ton, an expanded mining plan seems inevitable.

Possible output from two additional zones including the West zone where geological reserves stand at 4.2 million tons averaging 0.19 oz, were not included when Inco committed itself to plant construction.

Geological reserves of 2.9 million tons grading 0.22 oz are thought to be contained in a third “Main Zone” where a thick layer of overburden made exploration there the least of Inco’s priorities.

“If the East Zone supports the infrastructure, everything else is gravy,” said chief mine geologist Jean-Yves Cloutier.

Back in April 1987, partners Inco Gold (60%) and Golden Knight Resources (40%) announced production after extracting a 12,000-ton bulk sample from at a depth of 200 m on the East Zone. After silling out the ore zone on the 150-m and 200-m levels, Inco will install access drifts at depths of 125-m, 175-m and 200-m. West zone

If and when the West Zone is brought on stream, Inco will base its production decision on an almost identical exploration plan Cloutier says.

“Due to past experience, we are confident that reserves on the West Zone will be exactly the same as the East,” Cloutier told The Northern Miner. To handle increased production, the milling facility will contain a grinding section capable of handling 1,800 tpd, he said.

When The Northern Miner visited the facility last week, contractor McIsaac Mining and Tunnelling was just past the halfway stage on construction of a ramp designed to access the West Zone at a depth of 200 m.

Scheduled to be completed in May, the decline ramp will allow Inco to extract a 12,000 bulk sample and complete 1,200 m of diamond drilling. As part of a phase- two project, McIsaac will continue on to the 300-m level and drift towards the east side.

“We’ve experienced some water inflow problems on the west ramp but the ground appears to be competent,” said chief engineer Mike Sylvestre.

While Inco is known for developing its own mining equipment, the company is using conventional equipment including 39-tonne scoop trams on this project. “If the depth changes, we could change our way of thinking,” said Petracchi who was a superintendent at Inco’s Creighton mine in Sudbury, Ont., before he was asked to manage the Golden Pond project.

Meanwhile, some 70 km of power lines bringing electricity from Normetal to the mine site will be installed by Mid-may says Petracchi. Construction of a tailings pond also got underway last week.