This photo is of the bedrock wall of the west shaft of the Fox River crossing. Construction of the shaft began by removing the earth inside a 36-foot diameter casing shaft from the surface down to bedrock. A concrete seal was then poured to stabilize the floor and prevent excessive water leakage into the shaft. Once this is done, construction crews drill holes down into the rock (the grooves in the wall show where crews have drilled). Explosives are then placed into the holes and detonated. The fragments of rock are removed and the rock shaft is created.