WorldWide Drilling Resource

The Extraordinary World of Mining: Canada’s Diavik Diamond Mine Part 1 Compiled by Editorial Staff of WorldWide Drilling Resource ® For most of the 20th century, Canada’s treasure chest of diamonds remained hidden in the ground. In fact, most people's knowledge of dia- monds probably brings operations in Africa to mind, or diamond trading centers in Europe. However, things began to change for Canada in 1991, when two ge- ologists, Chuck Fipke and Stewart Blusson, discovered evidence of dia- mond-bearing deposits, or kimberlite pipes in Northwest Territories. Since then, the Diavik Mine has become Canada’s largest diamond mine in terms of carat production. Diavik was established following the discovery of four kimberlite pipes in 1994 and 1995. The mine site is located in one of the planet’s most unique and remote locations: wilderness on a 7.7-square-mile island at Lac de Gras, Northwest Territories, approximately 186 miles from Yellowknife, the territorial capital, and just 136 miles south of the Arctic Circle. In winter, temperatures at the site in Lac de Gras regularly reach -40ºF (-40ºC), and an ice road is required to transport supplies. Diavik began producing diamonds in January 2003, and the company sold its first rough diamonds in March of the same year. After several years of studying renewable energy resources and planning, Diavik built the first large-scale wind farm in the Northwest Territories. It is the world’s largest wind-diesel hybrid power facility and a pioneer achievement in cold climate renewable energy. Four 2.3-megawatt turbines were constructed in 2012, with a capacity of 9.2 megawatts. The wind farm, which has achieved peak power penetration of 52% (one-half of the mine’s energy needs), began delivering power to the mine’s grid on September 28, 2012. By diversifying the energy mix at the mine, Diavik is offsetting some of the risks associated with transporting diesel on the annual, seasonal ice road. The pipes currently mined at Diavik were originally under the waters of Lac De Gras and were discovered by drilling through ice. To mine the pipes, a dike was built as a barrier around them and water was pumped out. Open-pit mining then began on the lake bottom. As the surface-mineable ore was depleted, production shifted underground. Total investment to construct the underground mine was approximately $800 million. Construction required several miles of tunnels, rescue bays, ventilation and dewatering systems, as well as maintenance areas. Associated surface works included construction of a backfill plant, along with infrastructure to double the mine’s power generation and water treatment capacity. In 2013, Diavik’s first full year of production as an all-underground mine, an estimated 2 million tons of ore were mined, pro- ducing 7.2 million carats of rough diamonds. Learn about Diavik miners next month in Part 2! Diavik summer A154 dike and open pit. Dykes were creat- ed to allow open-pit mining of ore bodies found in extinct volcanoes just offshore. 33 WorldWide Drilling Resource ® DECEMBER 2017