Sandhoging is highly skilled and extremely dangerous work. "A man a mile" is the daunting formula that the sandhogs have accepted and that history has proven to be true. Twenty-four men have died on the Water tunnel #3 job since its conception in 1969--roughly a man for each mile of tunnel constructed.

Sandhogs still use the conventional way of mining--drill and blast with dynamite--to create the shaft and a starter tunnel, but the majority of mining today is done with a massive tunnel boring machine (TBM). It's essentially a big drill, 13 feet in diameter and 100 feet in length, which pushes out 1.5 million pounds of thrust on the face of the rock. Once the tunnel is mined completely, the next and final step is concreting its exposed surface.

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