In November 2008, Structural Preservation Systems (SPS) was retained to install a soil-mix secant wall at the intersection of Canal Street and Washington Street near the Holland Tunnel in New York City. The wall was installed for lateral support of an historic residential building adjacent a new construction site with a 10-foot excavation. The soil-mixing method utilized a 14-inch diameter reamer bit which spun while cement was projected out of small ports on its side. As the hole was drilled downward, the spinning action mixed the soil and sand with the cement. These soil-mix elements were designed to be drilled to a depth of 10 feet below grade, with the exception of every fourth element which was drilled to 25 feet, with a 9-5/8" steel casing inserted in the middle to provide reinforcement and facilitate whaler and raker connections.

SPS worked daily with the general contractor to overcome limited access conditions throughout the site and also worked diligently with the engineer to achieve a high level of quality control. After the following underpinning was completed, SPS was informed that the historical structure adjacent to the work measured zero settlement.