Robert B. Somerville was contracted to install two duct bundles under the Bow River. Each bundle included 7 DR13.5 NPS 6 HDPE pipes and three NPS 4 HDPE grout lines. Prior to drilling, Somerville installed NPS 48 casing on the entry side of each crossing to isolate the cobble and gravel layers from the drill path. The cobbles were removed for the drill path on the exit side by installing a shoring box and excavating to the bedrock.
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