The Statue of Liberty
Liberty Island
New York, New York

In August of 1985 COOK completed the installation of a 36" diameter, 100 foot deep water tight elevator jack hole within this national monument.

National Elevator Company

COOK's involvement with this project began in the design phase during which COOK conducted a technical feasibility analysis for the installation of the jack hole through the base of the Statue of Liberty. COOK's analysis included the potential impacts of a variety of drilling methods on the Statues foundation. The foundation consisted of 13 feet of massive granite ballast blocks stacked on top of each other. COOK's analysis concluded that a four-foot square shaft would have to be hand excavated through these materials exposing the underlying bedrock. After the completion of the hand excavation the 36" diameter jack hole would be excavated by air rotary drilling techniques to a depth of 100 feet. The large diameter of the jack hole was necessary to allow for the installation of a full-length watertight steel liner within the jack hole. A secondary watertight PVC liner would than be installed within the outer steel liner.

The jack hole itself was located within the center core of the statue. The location of the jack hole required COOK to design and fabricate a drill rig portable enough to enter the Statue, yet powerful enough to drill the 36" diameter hole through the underlying bedrock to a depth of 100 feet. Additional restraints on the design of the equipment was the need to insure that the jackhole was drilled to the strict plumb and alignment tolerances required.