Abstract: At 9:15 a.m. on August 2, 2012, an employee was bolting a newly installed backflow preventor in a trench when the excavator operator attempted to extend the trench with a bucket shovel. The bucket shovel detached from the boom arm of the excavator and rolled down into the trench, striking the employee in the upper back. The bucket shovel detached from a JRB Quick-Coupler attached to the boom arm of a Komatsu PC 200 excavator as the excavator operator attempted to extend a trench where an 8 inch water pipe was being connected to a backflow preventor. The bucket shovel rolled aproximately 1.5 rotations into the trench (about 8 feet) and struck the employee working in the trench. His back was to the excavator and the teeth of the shovel struck the employee in the upper back. The excavator operator, who was also the field supervisor and competent person, failed to conduct the required procedure to ensure that the bucket shovel was securely attached to the Quick-Coupler device prior to operating the boom arm over the end of the trench. The employee suffered blunt force trauma to the posterior ribs, punctured lungs, and lacerated heart and was dead upon arrival at the hospital.