CLIENT: Williams Operating Corporation (subsidiary of Barrick Gold)
PROJECT: Hemlo Mine Reclaimed Pump Station
PROJECT TYPE: Brownfield
LOCATION: Ontario, Canada
SERVICE SCOPE: Infrastructure Design
Barrick’s Hemlo Mine tailings dam pump station is located on a dam wall separating two existing operating tailings dams. The two vertical multistage spindle pumps pumping from one side are in an area where silting is becoming an issue as the tailings dam deposition levels rise. Halyard were contracted to identify an alternative site to locate the pumps and to design an all-weather enclosure to allow year-round access to allow for return water to be pumped from the tailings dam back to the process plant.
Halyard decided to relocate the pumps to a floating barge anchored to the dam wall and located in a deeper section of the tailings dam. As the dam wall is due to be raised in the coming years to extend the tailings dam design life, this solution was an elegant way to allow for the continuation of pumping with only a day downtime to relocate the pumps to the floating barge once the barge was installed.
Halyard undertook the structural design of the barge and walkway access bridge which included crawl beams within the enclosed building housing the pumps to lift the pumps off their mountings and onto a trolley that could be winched up a track installed in the walkway.
Additionally, subsurface fans, designed to continually circulate water were incorporated into the barge design to prevent freezing of the water surrounding the barge.