“The miner down there in his cut- and-fill stope couldn’t tell if he was in ore or waste,” he told The Northern Miner Magazine. Miners had to wait for assay results from face and wall samples to determine where next to mine. The orebody, an altered sedimentary deposit, is quite variable and, because of the need for constant and time-consuming assays, production shortfalls frequently occurred.
Compounding the problem was the miners’ inexperience with mechanized cut-and-fill methods. They had been drawn from Sherritt’s Fox operation, a copper-producer in the area, after that mine had closed. “The mill was nearly always short of ore and the grade was much less than expected.” The original feasibility study had called for a 900-tonne-per-day operation with a millhead grade of close to 6.8 g gold per tonne. The actual figures were about 700 tonnes-per-day at 5.5 g per tonne. Mill recoveries came up short as well, from a projected 89% to an actual 86%-87%. The mill is conventional carbon-in-pulp with a 2-stage crushing system and cyanide leach.
When Hayes took over, cut-and-fill was scrapped in favor of open-stoping long-hole methods. Sub-levels are driven at vertical intervals of 50 to 60 ft and the long holes are drilled between sub-levels — a standard long- hole operation. “Open stoping gives us a little more ore.” Goodwin said. “We’re not living hand to mouth.”
The original operation also relied on a simple rock-breaker as a primary “crushing” unit underground. That was identified as another severe bottleneck. So a Lokomo 30×40-inch jaw crusher was ordered. The installation began on a Thursday, Goodwin recalled, and was completed by Saturday with almost no interruption to production. V.B. Cook Engineering of Thunder Bay, Ont., did the design work.
With these physical changes and a management philosophy that emphasizes worker participation in decision- making, the mine is now running at 1,100 tonnes per day and, for the last three quarters in 1988, was making money. But Goodwin says fine-tuning the operation is still a priority. Currently, engineers are examining drill patterns, explosives and the optimum distance between sublevels. Any refinements that might boost production or improve overall productivity will be considered (maximum production has yet to be achieved). In terms of maintenance procedures, MacLellan seems committed to a modern program. It has computerized the maintenance system with a software program developed by Rushton International. The system aids in planning and scheduling maintenance and includes a file on the history of each piece of equipment.
Goodwin feels that beyond equipment and mining methods, the key component to the turnaround has been a managerial policy of involving rank-and-file workers in decision- making. “Initially, they (the workers) were worried. Morale was very bad, mostly because they knew the thing was losing money. Miners today are smart. They can put two and two together; they can look around and see when a mine isn’t going to last.” On the level of tangibles, the company has instituted a profit-sharing plan and a share-purchase plan. A new, 3-year agreement with the union has also been signed.
Proven, probable and possible reserves at the mine are 2.6 million tonnes grading 6.3 g gold per tonne. That’s enough to support the mine for six years but, with three distinct deposits on the property, Goodwin fully expects that new reserves will be identified.
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