Laronde Processing Plant (Preissac)

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Surface facilities at the LaRonde Mine include a 7,000 tons of ore treated per day milling complex, which has been expanded three times from the original 2,000 tons of ore treated per day rate that was established in 1988. The first expansion to 3,600 tons per day was completed at the beginning of 2000 and the second expansion to 5,000 tons per day was completed at the end of the third quarter of 2001. The expansion to 7,000 tons per day was completed in October 2002. This expansion consisted of additions to the grinding and precious metals circuits and modifications to the copper and zinc flotation circuits. A new ore handling system was completed at the end of 1999. It included a truck dump linked by a new conveyor gallery to a 5,000-ton coarse ore bin. The coarse ore bin feeds a semi-autogenous (SAG) mill that was installed at the end of 1999. Ore from the Penna Shaft is transported over the 1.2 kilometre distance to the ore handling facility by 35-ton trucks.

The milling complex consists of a grinding, gravity, copper flotation, zinc flotation, and a precious metals recovery circuit and refinery. A copper concentrate containing approximately 75% of the gold and byproduct silver and copper is recovered. The zinc flotation circuit produces a zinc concentrate containing approximately 5% of the gold. The remaining 20% is recovered by a precious metals circuit including a refinery using the Merrill Crowe process and shipped as doré bars. Both the zinc and copper flotation circuits consist of a series of column and mechanical cells that sequentially increase the zinc concentrate and copper concentrate quality. The precious metals circuit, that processes the tails from the base metal flotation circuit, consists of: 1) A leaching circuit (using cyanide); 2) A counter-current decantation (CCD) circuit that progressively
removes the solids (tailings) from the precious metal-rich leachate; and 3) A refinery that
precipitates, filters, and finally, calcines the precious metal-rich zinc pulp in order to produce doré.

Currently, water is treated at various facilities at the LaRonde Division. Prior to the water entering the tailings pond system, cyanide is removed at a cyanide destruction facility (associated with the paste backfill plant) using a sulphur dioxide (Inco) process. A secondary treatment plant located between the #1 and #2 polishing ponds uses a peroxysilica process to complete the cyanide destruction process. In addition, water with higher than permissible acidity is treated by lime in the mill complex prior to being released to the environment. In the first quarter of 2004, in response to revised Federal mining effluent regulations, the Company completed and commissioned a new water treatment plant that will eliminate tailing effluent toxicity immediately prior to discharge. The plant uses a biological treatment process. Prior to the completion of the water treatment plant, the Company retained excess water in its tailing pond complex. At the end of March 2004 treated water released from the plant successfully passed a toxicity test. The flow rate is steadily being increased as the biomass used to effect treatment continues to build up. Tailings not recycled underground in paste backfill, are stored in tailings ponds covering an area of approximately 293 acres and waste rock is stored in two waste rock piles with a combined volume of approximately 50.4 million cubic feet. The Company holds mining claims to the north-east, to the east and to the south-east of the tailings ponds that would allow expansion of the tailings ponds and the establishment of additional waste disposal areas.