Abstract: At about 1:30 p.m. on August 20, 1993, Employee #1, who was installing an underground electric circuit for new traffic signals, was working in a boring pit that was wet and muddy. A water pump was being used to remove excess water. Employee #1 was standing on a metal track used by the machine when he lost his footing. As he fell, his right hand struck the boring machine's control lever and knocked it into reverse. Employee #1 had placed a large wrench on the 3 inch boring pipe and the pipe, with the wrench attached, rotated counterclockwise and struck his right hand, which was pinned against the side wall of the pit. The blow cut off his right index fingertip. A coworker found the amputated fingertip and drove the injured employee to a local hospital, located a few blocks away, for medical treatment, but the doctor was unable to reattach the fingertip.