For the cutoff wall installation, part of the Boone Dam Internal Erosion Remediation Project, the Treviicos-Nicholson Joint Venture selected the secant piles technology as the most appropriate and safest methodology to address all the dam safety requirements.
The Secant Pile was installed maintaining a strict alignment and overlap requirements while penetrating through a challenging mixture of soil and highly weathered rock within the upper portions of the dam’s foundation. The cutoff is keyed into the sloping face of the existing concrete dam, forming a continuous composite seepage barrier along the entire alignment of the earthen dam. Over 300 secant piles were installed to create 850-ft long secant pile barrier, totaling 113,000 square feet of cutoff wall, and approximately 27,000 cubic yards of concrete.
Verification of the verticality, embedment and concrete quality of each element forming the wall was critical.