Currently in care and maintenance 18 km north of Stewart, BC, the Premier gold mine is owned by Ascot Resources Ltd.
Arthon, in partnership with Belvedere Place Contracting (BPC), completed updates to Premier's tailings storage which included upgrades to the main dam face, spillway, seepage monitoring pond, and mine water treatment plant settling ponds as well as raising the fuse plug.
For the main dam, the work involved placing rockfill and riprap on the upstream slope. For the spillway, work involved excavating rockfill and bedrock and placing granular fills, rockfill, and riprap while maintaining road access across the spillway. Raising of the fuse plug required placement of sand and gravel, rockfill, and riprap to raise the crest to the same elevation as the main dam.
Upgrades to the seepage monitoring pond involved scaling loose rock from adjacent slopes; removing debris from the basin; breaching the existing seepage monitoring pond dam; repairing cracks in the concrete face of the dam; placing a 9.0 m manhole including related pipes; gate, and weir; and placing sand and gravel, rockfill, and riprap.
Upgrades to the mine's water treatment plant settling ponds required excavation of bedrock, dam fill materials, sludge, tailings and organics, foundation preparation, and placing rockfill and sand and gravel for the upper dam and the divider dam.
Challenges overcome during the project include
Strict environmental management requirements
Drilling and blasting in challenging conditions