On February 7, 1996, about 0815 mountain standard time, N32FR, a Bell 206B helicopter, operated by the U.S. Department of the Interior, rolled over during takeoff near Kemmerer, Wyoming, and was substantially damaged. The commercial pilot and his passenger were not injured. Visual meteorological conditions prevailed and a company flight plan had been filed. The public use flight was conducted for a geological survey under 14 CFR 91. According to the pilot, he attempted a takeoff from snow-covered terrain. As the helicopter began to lift up, it became displaced in the snow and moved forward. The pilot then decreased collective in an attempt to stop the forward motion and reposition the helicopter. At that time, some of the snow became displaced beneath the helicopter, and it rolled over to the right. The rotor blades contacted the ground and were damaged. The entire rotor hub assembly was separated from the mast. Damage to the tail boom and cabin structure was also reported. No preimpact mechanical malfunctions were reported. The pilot reported that prior to landing at the landing zone, he performed a low pass. He then attempted to pack the snow under the helicopter's snow pads, and then settled onto the snow and shut down the engine. His two passengers exited the aircraft to perform scientific observations. One of the passengers then re-boarded the aircraft and desired to be flown to another location. It was during this takeoff that the accident occurred.