Mining

Mining of Deposit No. 1 at Mary River will use conventional open pit drilling and blasting techniques, electric shovels and 160 tonne haulage trucks. A cut-off grade of 58% will be used for initial open pit design, and life-of-mine scheduling, with the remainder of the material classified as waste. Waste material will be stored in rock piles located adjacent to the open pit. The ratio of waste rock to ore through the life of the open pit is expected to average 1.7:1. Since no further processing of the ore will be needed before shipment to market, the construction and operation of tailings management facilities will not be required.

Ore from the pit will be hauled to a primary crusher, crushed to less than 200 mm in size and conveyed to two secondary crushers for further size reduction. Lump ore (less than 31.5 mm and greater than 6.3 mm) is expected to constitute 75 to 80 % of the crusher product with the balance (less than 6.3 mm) being sinter feed or fines. Linear stockpiles covering a total area of approximately 12 hectares will be established near the rail loading facility for the crusher product. The stockpiles will be equipped with rail-mounted stacker/reclaimer systems for loading rail cars.