A summary of the construction of the Brucejack Gold Mine
As Pretivm Resources’ Brucejack Mine nears production, it’s exciting to look back on the construction process.
As Pretivm Resources’ Brucejack Mine nears production, it’s exciting to look back on the construction process. Pretivm and its contractors overcame the intense challenge of constructing the mine and facilities in northwestern British Columbia. Diligent planning allowed them to work ahead of schedule even through the harsh winter months.
Construction began September 2015
The focus of the fall of 2015 was preparing the site for construction of the buildings to begin in the following spring. Earthwork began, and diversion ditches were excavated. Brucejack Road was widened for transportation. Underground, the focus switched from exploration development to mine infrastructure construction.
All major equipment had been ordered, including the ball mill and SAG mill. Temporary generators were delivered, commissioned and ready to power construction.
Earthwork, as well as building the mill and camp pads, was the focus throughout the winter of 2016. Pretivm updated the construction cost and working capital estimate for the project in February from the numbers estimated in the June 2014 feasibility study.
The winter conditions, while challenging, did not slow Pretivm’s construction pace. In March 2016, the foundation of the camp was poured and the mill pad levelled. Over 700 employees and contractors were working to complete the project.
The winter weather started to fade as Pretivm continued to work on the permanent 330-person camp foundations. The camp modules were constructed offsite and brought in for assembly. Pretivm began building the Valley of the Kings portal pad. The portal building is where the gold ore is conveyed to the mill. Underground construction advanced at an impressive rate of 20 metres each day.
By June of 2016, the construction team moved forward at record speed to optimize its window of good weather. The shell of the permanent camp neared completion, including electrical work and plumbing. The foundation of the mill was poured, and the site was prepared for the arrival of the SAG and ball mills. The steel structure construction began.
The transmission line towers were the focus in July. The bases and towers were successfully installed using a high-capacity air crane. These transmission towers connect Brucejack to the BC Hydro power grid. The roof of the mill was installed. The surge bin discharge chutes also arrived as the interior of the mill became the focus.
Throughout August, the walls of the mill were installed. The goal was to completely enclose the mill building so construction could continue indoors. Mill equipment continued to arrive.
Snow started to fall as the last towers were constructed, and the mill building was fully enclosed. This allowed construction to advance quickly indoors over the winter months. The foundations and steel structures for the major pieces of equipment were installed. The fire and water tanks, and electrical room were constructed. The tailings concentrator and stock tank foundations were poured. The electrical surge bin was entirely enclosed.
Construction continued at the Brucejack site, despite heavy snowfall. The tailings thickener and the SAG mill main bearing housings were installed. Other milestones included the assembly of the floatation tanks and tailings thickener, and electrical installations. Across the site, the portal construction continued at an increased speed of 30 metres each day. Vents were installed, and 30,000 tonnes of ore were stockpiled for commissioning. Most notably, the transmission towers were completed, and workers began the process of energizing the line.
Work continued at the underground portal building. Equipment assembly inside the mill neared completion. The permanent camp was fully operational.
Construction was ahead of schedule, and 110,000 tonnes of ore had been stockpiled for commissioning.
March was a noteworthy month at the Brucejack Mine. The transmission line was completely energized, and dry commissioning began.
Wet commissioning began with the introduction of the first ore.