Operations
LaRonde includes underground mining operations, a mill complex, a water treatment plant, a secondary crusher building and related facilities. The operation had 663 permanent employees on Dec. 31, 2008.
While production has come from three different mine shafts, the mine currently uses only the Penna Shaft to hoist LaRonde's ore production of approximately 7,200 tonnes per day. The Penna Shaft, extending from surface to 2,250-m depth (Level 225), is believed to be the deepest single-lift shaft in the Western Hemisphere.
The mining method is predominantly transverse longhole stoping with delayed cemented backfill. Saleable byproducts of the mining operation include silver, zinc, copper and lead.
The mill complex includes copper and zinc flotation circuits as well as a precious metals recovery circuit and refinery. The mill produces doré bars (containing gold and silver), zinc concentrate and copper concentrate.
History
In 1979, Agnico-Eagle bought shares in Dumagami Mines Ltd., which then owned the rights to the property that now hosts the LaRonde operation. Three years later, Dumagami Mines decided to carry out a two-phase exploration program that would ultimately take the mine into production.
A study determined that the existing gold deposit was uneconomic, and a decision was made to stop the underground exploration program at Dumagami in December 1985. However, later that month, the exploration team discovered the West Zone—a new gold zone at the 180-m level. The West Zone yielded promising results, and further exploration in 1986 confirmed the earlier high-grade gold values.
The mine went into commercial production in October 1988, reaching 1,810 tonnes of ore per day by 1989. It was named “LaRonde” in honour of Don LaRonde who had been instrumental in the project. In 1992, Dumagami transferred all of its property and assets including the mine to Agnico-Eagle, and was subsequently dissolved.
The LaRonde mine has maintained a steady-state operation of about 7,200 tonnes per day for the last six years. Since 1988, it has produced more than 4 million ounces of gold.
Expansion Project
In May 2006, we began construction to extend the infrastructure at the LaRonde mine, in order to access the ore below Level 245 (2,450 metres depth). This gold-copper and zinc-silver mineralization is not accessible by the current Penna Shaft.
Access to the deeper ore will be via an internal shaft, or winze (called “Shaft No.4”) extending to a depth of approximately 2,900 m. A series of ramps will enable mining to a depth of approximately 3,100 m below surface. The project also includes an expansion of the mill facilities.
Production from Shaft No.4 is expected to begin late in 2011, with the full production rate reached in 2013. Post-2013, the plan is to produce 6,000 tonnes of ore per day at an average gold grade of approximately 6.0 grams per tonne, resulting in annual production of approximately 380,000 ounces. For the same period, annual byproduct production is expected to average 1.0 million ounces of silver, 5,700 tonnes of copper and 12,300 tonnes of zinc. It is expected that the LaRonde Extension will extend the mine life to 2024.