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For eight months of the year, the mine is surrounded by ice up to 1.5m thick. Access is by air only except during the coldest weeks of the winter, when an ice road built over frozen lakes and ponds allows re-supply. For about ten weeks, the road links Diavik with the city of Yellowknife and an all weather highway to southern markets. Trucks hauling diesel fuel and other supplies on the ice road take up to 16 hours to make the 350km trip. Slow speeds are paramount as the vehicles actually push a wave under the ice ahead. Overdriving the wave can snap the ice with dangerous results.

Currently, there are four pipes in Diavik's 20 year mine plan. Together, the A154 South, A154 North, A21 and A418 pipes have an estimated resource of 106.7 million carats within 27.1 million tonnes of kimberlite ore. Grade is an estimated 3.9 carats per tonne, among the world's highest. A154 South, the richest of the four pipes, is the first to be mined.

Prior to accessing A154 South's defined resource zone, Diavik's mining team concluded pit prestripping and removal and processing of a fine grained layer of kimberlite and till (boulder clay) above the main body of the pipe. Prestripping and subsequent removal of the lower grade ore, a mix of till, mudstone lenses, ice, kimberlite, and diamonds, was completed in mid 2003, allowing access to the defined ore reserve below.

"It's early October, and we're slightly ahead of target for removing waste rock and ore delivery," said mining manager Dave Passfield. "All is going according to plan. We are getting some groundwater in the pit but our water collection system is working as expected."



For eight months of the year, the mine is surrounded by ice up to 1.5m thick. Access is by air only except during the coldest weeks of the winter, when an ice road built over frozen lakes and ponds allows re-supply. For about ten weeks, the road links Diavik with the city of Yellowknife and an all weather highway to southern markets. Trucks hauling diesel fuel and other supplies on the ice road take up to 16 hours to make the 350km trip. Slow speeds are paramount as the vehicles actually push a wave under the ice ahead. Overdriving the wave can snap the ice with dangerous results. Currently, there are four pipes in Diavik's 20 year mine plan. Together, the A154 South, A154 North, A21 and A418 pipes have an estimated resource of 106.7 million carats within 27.1 million tonnes of kimberlite ore. Grade is an estimated 3.9 carats per tonne, among the world's highest. A154 South, the richest of the four pipes, is the first to be mined. Prior to accessing A154 South's defined resource zone, Diavik's mining team concluded pit prestripping and removal and processing of a fine grained layer of kimberlite and till (boulder clay) above the main body of the pipe. Prestripping and subsequent removal of the lower grade ore, a mix of till, mudstone lenses, ice, kimberlite, and diamonds, was completed in mid 2003, allowing access to the defined ore reserve below. "It's early October, and we're slightly ahead of target for removing waste rock and ore delivery," said mining manager Dave Passfield. "All is going according to plan. We are getting some groundwater in the pit but our water collection system is working as expected."
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Review is published by Rio Tinto, 6 St James' Square, London SW1Y 4LD, England Telephone +44 (0)20 7930 2399 Editor: Cherry DeGeer