Abstract: Employee #1 was working in a trench in a street in Santa Ana, CA. The trench lacked adequate shoring, was in class C soil, and was 10 ft or more in depth; it also was subject to street traffic vibrations and had several inches of water at the bottom. Employee #1 had just started to climb out of the trench onto a 64 in. diameter pipe that was in the trench, when the south side of the excavation caved in, pinning him against the pipe and covering him completely. An air pocket permitted him to breathe. A coworker noticed the cave-in and went for help. Employee #1 was dug out of the trench and taken to a doctor, who treated him for minor injuries. Since then he has gone to a another doctor, who is treating him for a back problem.