Abstract: At 7:30 p.m. on November 30, 2021, an employee, a waste treatment operator, was found dead next to an empty closed drum used to store Cascade 2, a sodium hydrosulfide solution. According to video surveillance, the employee was seen pushing an empty 55-gallon drum into the waste treatment area. The employee was not seen on the security camera again. A few hours later, a coworker was looking for the employee, and then found him lying unresponsive next to the empty plastic drum. The coworker that found the decedent usually received a briefing before relieving him of duty. The employee was killed due to natural causes. The employee suffered a cardiac arrest while on duty. There were no violations found. The worksite was an electronic circuit boards/components assembly and manufacturing plant. The waste treatment unit was responsible for maintaining and monitoring the wastewater treatment systems to maintain permitted discharge requirements before releasing the water back to the District (community) wastewater plant.