Dominion Diamond Mines Dominion Diamond Mines Dominion Diamond Mines (formerly known as Dominion Diamond Corporation, Harry Winston, and Aber) is a Canadian specialist diamond mining company. The company holds a 40% stake in the Diavik Diamond Mine Project. Production at the Diavik Diamond Mine, Canada's second diamond mine, is operated by Dominion Diamond Mines' joint venture partner, Diavik Diamond Mines Inc., a subsidiary of Rio Tinto Group. The mine began producing diamonds in November 2002. In 2012 the company purchased all of BHP Billiton's diamond assets; the primary asset is the Ekati Diamond Mine, which is adjacent to the Diavik Mine. Diavik and
Permafrost construction on permafrost owing to the change of soil properties of the ground on which structures are placed and the biological processes in permafrost, e.g. the preservation of organisms frozen "in situ". Building on permafrost is difficult because the heat of the building (or pipeline) can thaw the permafrost and destabilize the structure. Three common solutions include: using foundations on wood piles; building on a thick gravel pad (usually 1–2 metres/3.3–6.6 feet thick); or using anhydrous ammonia heat pipes. The Trans-Alaska Pipeline System uses heat pipes built into vertical supports to prevent the pipeline from sinking and the Qingzang railway