Abstract: At approximately 10:45 a.m. on October 4, 1993, Employees #1 and #2 were working in a trench to chip off a portion of cement from an existing pipeline in preparation for cutting and removing the pipeline. A pneumatic hammer was used for chipping. The trench was about 50 ft long, 8.5 ft wide, and 8 feet 8 in. deep. The steel shoring system was not in accordance with shoring plans. The east end of the trench was not shored. The trench was between two heavily traveled traffic lanes used for cars and very heavy trucks. Both employees were at the east of the trench when the east end caved in burying Employees #1 and #2. Employee #1 was killed. Employee #2 received internal injuries and was hospitalized.