In preparation to depart, the crew had loaded the passengers, the doors had been closed and the aircraft was secure. The right engine was started and was idling in feather. Just as the left engine was started a young woman ran out from a nearby group of bystanders towards the aircraft. The co-pilot waved her away and the captain aborted the start. The woman returned to the bystanders area. When the left engine was restarted, the woman again ran towards the aircraft and into the right rotating propeller; evidence revealed that she was impaired by alcohol. There is a small terminal building at the airport, but no restraining fence between the building and the ramp. Passengers and bystanders are therefore free to move throughout the area.