Helicopter Upset

May 19/13-An Aurora Helicopters Ltd. (operating as Wood Buffalo Helicopters) AS350-B2 (C-GYWB) was landing on a site at the edge of muskeg approximately 45 nm NW of Fort McMurray, AB airport (CYMM). The pilot landed the helicopter and performed a “seating check”. Having determined that the site was suitable, the landing and normal shutdown were completed. During the shutdown, the passengers began to unload their equipment from port side equipment basket. GYWB began to tilt aft and to the left during the unloading. With the passengers waiting by the tree line, the pilot attempted to restart the aircraft for repositioning. The main rotor blades did not turn much when fuel was added, so the aircraft was shutdown. An attempt was made to prop up the helicopter by placing logs under the skids. A second restart was then attempted, however, the helicopter began to shake and the start was aborted. A post shutdown inspection indicated that damage had been sustained to the tail boom and tail rotor blades when they contacted the water.