PG&E commissioned the pole replacement project in El Dorado County as a fire hardening and asset modernization effort.

Crux provided EPC micropile foundation services for two replacement structures – one H-frame and one three-pole – located in difficult-access areas and requiring helicopter construction support.  The structure locations were also incredibly remote, located more than two hours away from the nearest amenities, necessitating additional advance planning.

There was no geotechnical data available during the design phase, and Crux’s engineering team utilized publicly available information as well an internal data library and site observations to develop preliminary foundation schedules.  Standard penetration testing was completed during micropile drilling to confirm subsurface conditions and determine the specifics of the foundation installed in that location.  Micropiles lend themselves well to these circumstances as the materials and equipment required to install can be compact and helicopter-portable, and Crux’s patented installation methods allow for efficient design changes during construction.  Ultimately, 21 total piles were installed to depths between 60 and 70 feet.

Additional project challenges included extremely steep and difficult drilling conditions; being subject to strict environmental regulations; and having to schedule work windows around allowed outages and area wildfires.