Abstract: Employee #1 was cutting a trench for a sewer line through what the company classified as solid rock. The rock had fissures and cracks and the excavation was on a known fault line. Most of the trench was not more than 3 feet deep, but at the accident site, because of the shape of the hill that it was on, the trench was 7 1/2 feet deep. The trench was being cut by a diamond saw 2 feet wide. The bottom of the trench was 2 feet wide and the top of the trench was 32 inches. Two large rocks separated from the south side of the trench. The first rock is estimated to have been 6 feet long, an average of 3 feet wide, and an average of 1 foot through. The first rock landed on Employee #1's head and pinned him between it and a cast iron pipe. The second rock was much larger. It sealed the top of the trench, but never came into contact with the first rock or with Employee #1, who was alive when he was removed from the trench. He was transported to the Dixie Medical Center, where he died about 2 hours later.