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Sigma and their staff completed Design and Construction Management Services on the 12-mile long section of I-11 which bypassed the Town of Boulder City, NV

Design Services include structural design and/or supervision of the structural designs for 11 bridges, which total over 2,296 feet in total on Phase 2. Sigma was also involved with the only bridge built on Phase 1 which was 278 feet in length. Construction Management on Phase 1 of I-II involved inspection of the 11 bridge structures, and 12 miles of 4 lane freeway, coordination of the material sampling and testing, coordination with multiple local, state and federal jurisdictional entities as well as supervising the monitoring of NOA (Natural Occurring Asbestos), and the SWPPP (Stormwater Pollution Prevention Program). The Inspection duties also included pre-blast inspections for the 356 blasts (each with approximately 80 holes) to produce 6.5 million cubic yards of rock. A portion of the material generated was processed onsite to produce 200,000 cubic yards of various aggregates which was used to create the roadways and embankment fills.

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