Abstract: Employee #1 and Employee #2 were installing components of a waterproofing system in a trench 54 ft long by 8 ft wide by 10 ft deep formed by concrete and dirt walls. A portion of the dirt wall (630 cubic ft) collapsed, which completely buried Employee #1 and buried Employee #2 up to his knees. Employee #1 died due to asphyxiation and Employee #2 received minor injuries. Company officials felt the trench was safe due to its width. Causal factors: water in trench bottom, which allowed undermining of toe; previous excavation adjacent to collapse site; vibrations from a loader; several feet of gravel and backfill added to the top of trench on that day. Inadequate ladder access; employees wearing protective helmets; little if any trench excavation hazard recognition training, company had a full time safety officer and a written safety program with only 47 words concerning trench safety.