YELLOWKNIFE, Northwest Territories DIAVIK DIAMOND MINES has won the NORTHWEST TERRITORIES ASSOCIATION OF PROFESSIONAL ENGINEERS, GEOLOGISTS AND GEOPHYSICISTS’ Professional Award of Merit for the Diavik A154 dike at its new diamond mine.
In its award certificate the association noted: "Technology developed in building the Diavik A154 dike creates a precedent that will enable further pipes at Diavik to be developed with confidence. It was the first dike of such design constructed in Canada and it creates a model that will be widely applicable across the tundra."
The A154 dike isolates part of the Lac de Gras lakebed from the main body of the lake, allowing the open pit mining to proceed. The dike is 3.9 km long, up to 25 m high and encloses an area of 1.5 km2. The dike comprises 2.2 million m3 of zoned rock fill and includes a plastic concrete diaphragm wall that extends through both the fill and the till foundation. The wall is married to the granitic bedrock by a continuous barrier of jet-grouted columns.
Engineers for mine construction were NISHI-KHON/SNC-LAVALIN. Dike design work was executed in SNC-Lavalin’s Montreal office. The civil contractor for the dike project was LAC DE GRAS CONSTRUCTORS, a joint venture of PETER KIEWIT SONS and NUNA LOGISTICS.
The NAPEGG is a self-governing body of professionals and maintains a web site at www.napegg.nt.ca.