CLIENT: Government of Yukon
LOCATION: Central Yukon Territory
The Faro Mine is located in the central Yukon, approximately 200 km north-northeast of Whitehorse. The Grum Sulphide Cell (GSC) is located within the Grum Waste Rock Dump at the Faro Mine Complex. The Yukon Government managed the construction of a high-density polyethylene (HDPE) liner and soil cover over the GSC in 2010 as part of early closure activities. During the following spring freshet, erosion occurred on the cover surface resulting in discharge of sediment and zinc laden water into the near-by Vangorda Creek.
The Yukon Government retained BGC to review the previous cover system design and construction, provide recommendations for repairs and water management, and to supervise construction of the repairs before the fall of that same year. BGC made a site reconnaissance visit, and by July started an assessment of previous root causes and necessary mitigation measures for the cover. Numerous modifications were made to bench grading and diversion channels. In addition, a new lined sedimentation pond was constructed at the toe, along with changes to the water management plan through pumping. BGC provided field engineering and construction management services during the construction of the mitigation measures which were completed by September of that year. No erosion or discharge occurred during the following year’s freshet and BGC is still involved with the on-going monitoring of the remediated cover.