In the mountains of northwest BC, we performed desktop and-field engineering reviews for a 138-kV transmission line to power a gold mine

Brucejack Mine – Transmission Line Geohazards and Geotechnical Assessment

Brucejack Mine is located 65 km north of Stewart, BC in some of the most rugged, mountainous terrain in the province. The interconnection of the mine to the municipal grid of Stewart required the construction of 55 km of 138 kV transmission line, including 140 transmission towers, in an area prone to rockfall, landslides, snow avalanches, and channel avulsion.

We were engaged to perform a geohazard, line routing and foundation design assessment with the principal goal of reducing the risk of damage to the transmission line while maintaining an economical, practical line routing design. We initially completed terrain stability mapping and a geohazards assessment for each tower location and the general proposed alignment using digital stereo-imagery using 3D mapping software, GIS, and LiDAR data. Finally, we performed full-time on-site review of the foundation anchor drilling for each tower location, and adjusted foundation designs based on results of the rock core drilling, in close collaboration with the client and contractor’s construction team.

Our geotechnical engineers, terrain scientists and power-transmission line engineers worked collaboratively to help the client find an economic solution through difficult and rugged terrain in an accelerated design and construction schedule.