Abstract: At approximately 8:30 a.m. on April 28, 2007, Employee #1 and a coworker were working in an excavated trench. The trench was approximately 25 ft long by 5 ft wide and 56-in. deep. The faces of the excavated trench were not protected with barricades to prevent falling material. Employee #1 was bent over operating a manual wheel type pipe cutting machine to remove an 8 ft section of 4-in. pipe. He was struck in the lower back by a large compacted section of dirt, approximately 18-in. by 12-in. by 5-in. thick, weighing approximately 40 pounds. Employee # 1 suffered a fracture to the L5 disk of his lower spine and was hospitalized.