Abstract: At approximately 2:30 p.m. on July 14, 1999, Employee #1 was working as a pile buck for FCI Constructors on a freeway seismic retrofit job in San Francisco. They decided to remove the trench shield in an excavation because it was too small. Employee #1 and his foreman had removed three of the four spreaders when the foreman had to step away and left Employee #1 to complete the job. He removed the pins to the last spreader and was headed toward a freeway footing when one of the metal side shields fell, pinning him against the concrete footing. Employee #1 suffered multiple fractures to his pelvis, two spinal fractures, and a crushed bladder.