Abstract: At 6:15 p.m. on August 19, 2022, two employees were digging a trench with a JCB 245XR Excavator for a storm sewer line that was located in the center of a new multi-residential housing complex that was under construction. The trench was approximately 29 feet long by 16 feet wide and 7 feet 6 inches deep. Both employees entered into a manhole section of an existing sanitation sewer line that was located approximately 6 feet from the trench. Both employees lost consciousness in the manhole section. The EHS service that attempted to conduct the rescue of the employees noted that the oxygen levels were at 12.1%. The employer had completed this sanitation sewer line prior to working on the storm sewer line. The employer did not have a means of testing the atmosphere in the manhole section, and the employees were not trained on OSHA requirements for working around and entry into confined spaces. Both employees died of asphyxiation.