After reviewing all statement and conducting interviews the following can be concluded; Operator1 and Operator2 were operating their PWC'S together on Lake Marion on 06/04/2010. Operator1 was alone on his PWC; Operator2 had a passenger on his PWC. The two PWC's were traveling toward I-95 Bridge on Lake Marion after leaving Mill Creek area of the lake. According to Operator2, Operator1 was crossing from his left to right and before Operator1 could cross the path of Operator2, they collided. Operator2, while operating his PWC, released the throttle on his PWC, and was not in control when he struck Operator1's PWC on its starboard side. All subjects went into the water and were then towed to land for help by Eagle Tours. Operator2 left the area and went to contact 911. While Operator2 was gone, two subjects contacted 911 and EMS arrived and transported Operator1 to Orangeburg Hospital for a leg injury. Operator1 was the flown to Richland Hospital for surgery. On 6/11/2010, while in surgery for an infection in his leg Operator1 passed away. The contributing factors to this boating fatality are; that Operator2 failed to maintain control of his PWC, by releasing the throttle, improper lookout, and maintain safe speed to avoid collision.