This project is the construction to Caltrans Specifications of two tunnels beneath San Pedro Mountain, each 30-feet wide and 4,200-feet long, designed with the New Austrian Tunnel Method. In addition to the tunnel, this project included a 1,000-foot bridge spanning the valley at Shamrock Ranch, re-alignment of Route 1 at the southern end providing transition into and out of the tunnel, operations and maintenance facility, and an earthen embankment and vegetation-covered roof to help the facility blend with natural surroundings. ISI provided daily materials testing of shotcrete samples.

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    Construction Value

    $343 Million

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    California Department of Transportation (Caltrans), District 4

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