- 1). Develop open pit mine. Most of the Canadian tundra diamonds lie underneath shallow lakes. Drain the water from each lake, excavate kimberlite from the open pit with large-scale shovel and trucking equipment designed to operate in frigid Arctic conditions. The kimberlite rock is shaped like a funnel with a wide opening closer to the surface. Open pit mining is suitable to extract diamonds from the wide opening of the kimberlite rock.
Employ blast hole open stoping to break harder rock ore that lies closer to the surface, which entails drilling holes perpendicular to the open pit face and blasting, i.e., exploding, the ore for removal and transport to the processing site. - 2). Move kimberlite ore to the processing plant for crushing. The Ekati Diamond Mine moves 18,000 tons of ore per day to the processing plant. After crushing, pure diamonds are extracted from the ore, using x-ray fluorescence sorters. Moving, crushing and sorting are done at the mine site area.
- 3). Dig underground mine, once open pit mining reaches narrowing bands of kimberlite ore. The Diavik Diamond Mine has transitioned from an open pit to an underground mine to recover as many diamonds as possible from the area, but with additional expense. The cut and fill method is employed to remove softer kimberlite rock that lies underground. Panels, one unit of mined ore, are mechanically cut out and replaced with backfill, material used to support tunnel structures to prevent roof collapse.
- 4). Haul panels to the surface. At the Diavik Mine, smaller hauling trucks are used ---- 50-ton trucks as opposed to the 250-ton trucks used on the surface. Underground air must be heated and every ton of soft kimberlite ore extracted needs to be backfilled with cement paste to prevent tunnel collapse. For other types of mining, such as coal mining, mine waste or rock can be used as roof support. To mine kimberlite safely, a paste backfill plant must be constructed on the surface to produce the cement paste backfill.
- 5). Protect water quality. Because the tundra diamonds lie beneath shallow lakes, water collection, diversion and treatment systems must be constructed. The Diavik Mine is situated on an island in a lake. The mining company created a collection and treatment system to allow water to flow around the open pit mine instead of into it, protecting the water until the mine is closed and the land is properly reclaimed.
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