Rio Tinto's Diavik Diamond Mine is one of two large scale diamond mines in Canada s North West Territories. The mine consists of four Kimberlite pipes; A154 South, A154 North, A418, and A21 all situated beneath Lac de Gras. Diavik first received approval in 2001 to carry out open pit mining of the A154 pipes. In order to construct an open pit mine in the middle of Lac de Gras a 3.9 kilometers perimeter dike needed to be constructed and the water pumped out. Prior to construction of the dike the soft lake bed sediments had to be excavated from the footprint of the dike.
In 2000-2001 FRPD s portable cutter suction dredger Explorer was mobilized from Vancouver to the North West Territories which included hauling over the infamous winter ice roads. FRPD had a short time line to assemble, launch, dredge, and disassemble in the few months of temperate weather available.
The second dike was constructed in 2005 joining the A154 dike to East Island. This time the dike was much shorter than the first at 1.3 kilometers in length but required deeper dredging to 32 meters. As per the A154 dredging the Explorer successfully completed the work in the few months available.