Abstract: At approximately 12:50 p.m. on August 30, 1991, Employee #1, of T & B Scottdale Contractors, Inc., was placing concrete using a manually-controlled concrete delivery hose attached to a concrete pumping truck. The pump truck was owned and operated by Pioneer Concrete Pumping Services, Inc. A Pioneer employee set up the truck, and was controlling the pumping and boom movement. After approximately 20 minutes of pump operation, the truck's right front outrigger broke through its dunnage and sank into the ground. The sudden movement jerked the pump truck boom downward. The employee was struck in the chest and shoulder by the concrete delivery hose, knocked to the ground, and pinned under the hose. He was hospitalized. He died 10 days later on September 9, 1991. The accident occurred because the truck was set up and operated on unstable soil, and the pump truck operator was not properly trained on how to set up the equipment or on how to recognize and avoid unsafe conditions.