The Diavik Diamond Mine is located on a 20 square kilometre island, informally called East Island, in Lac de Gras, approximately 300 kilometres by air northeast of Yellowknife, capital of Canada's Northwest Territories. The Arctic Circle lies 220 kilometres north of the mine.
Lac de Gras is 60 kilometres long, and averages 16 kilometres wide, with a shoreline length of 740 kilometres. The lake averages 12 meters deep, and has a maximum depth of 56 metres. Water temperature ranges from 0°C to 4°C in winter and 4°C to 21°C in summer. Aboriginal people named the lake Ekati, as the veins of quartz found in local bedrock outcrops resembled caribou fat.
Lac de Gras has a 4,000 square kilometre drainage area. This lake, with Lac du Sauvage to the northeast, forms the headwaters of the Coppermine River flowing 520 kilometres from western Lac de Gras to the Arctic Ocean.
Aquatic productivity of the lake is low due to low nutrients, low light during winter, eight months of ice, and low water temperatures. Lake water is very pure, resembling distilled water, and is crucial to the preservation of wildlife in the region, which, in turn, play a key role in the traditional lifestyles of local Aboriginal communities. Lake trout, cisco, whitefish, arctic grayling, burbot, longnose sucker, and slimy sculpin are among fish species which thrive in the lake.
The stark tundra landscape surrounds the Diavik Diamond Mine. Named the "Barren Lands" by early explorers due to its lack of trees, the region is prolific with lakes, bedrock outcrops and glacial deposits of boulders, till, and eskers. What little soil is found is of cryosolic order - formed where permafrost occurs within one to two metres of the surface - and is characterized by layers that are disrupted, mixed, or broken, by freeze-thaw activity.
Vegetation of the region includes dwarf birch, northern Labrador tea, blueberry, mountain cranberry, and bearberry, with willow, sphagnum moss, and sedge tussocks dominating wet lowlands.
84 bird species and 16 mammal species are summer visitors or permanent residents of the region. Native wildlife includes grizzly bears, wolves, foxes, arctic hare, ground squirrels, and wolverines. In spring and fall, portions of the Bathurst caribou herd migrate through the region. To help protect migrating caribou, caribou advisory signs have been installed on all haul roads to and from the mine to ensure that caribou and other wildlife have the right of way.