PROJECT OVERVIEW
This comprehensive design-construct project addressed rockfall hazards at Fremont Canyon Power Plant through debris removal and installation of five engineered rockfall protection systems. The scope encompassed evaluation and replacement of existing deteriorated protection infrastructure in ravines south and west of the facility, along with targeted rock stabilization within the access tunnel's Zone 11 section.
The project presented significant logistical complexities, requiring careful coordination of construction activities with ongoing power plant operations. Site accessibility posed considerable problems, with steep terrain and limited equipment access. The removal of 700 cubic yards of accumulated debris from remote locations demanded innovative methods to achieve project objectives without compromising operational requirements or environmental considerations.
The existing ageing rockfall nets were in poor condition, offering no effective rockfall protection to the power plant located at the base of the ravines. The lower rockfall net had reached its retention capacity, creating ongoing geological hazards affecting the facility's access infrastructure.
PROJECT SOLUTION
Five new rockfall barrier systems were installed across the western and southern ravines, incorporating four VX Attenuators up to 30 feet tall and 60 feet wide, and one SVX Attenuator 75 feet long by 30 feet high. The upper ravines were designed with basal openings to assist in future maintenance and incorporate self-cleaning capabilities to reduce ongoing maintenance requirements.
Within the tunnel's Zone 11 section, Tecco steel mesh was installed using 8-foot epoxy-grouted rock bolts across the 20-linear-foot treatment area. The epoxy grouting approach minimised disturbance and cleanup within the tunnel while facilitating an accelerated program to reduce operational disruption.
The project deployed our Spider excavator to reach the lower rockfall net via the western ravine, overcoming significant accessibility constraints in steep terrain. Material removal operations utilized a purpose-built zip-line system specifically designed for this project, enabling efficient transport of 700 cubic yards of debris in dumpy bags across challenging topography.
The replacement program restored comprehensive rockfall protection using modern engineering standards, with careful coordination maintained throughout to preserve power plant operations while addressing the geological hazards.
Fremont Canyon Power Plant, WY
Rockfall Mitigation
ROCKFALL BARRIERS, ROCKFALL ATTENUATORS, ROCKFALL MITIGATION, ROCK BOLTS, ROCKFALL PROTECTION, MESH INSTALLATION, DESIGN & CONSTRUCT