A Prescott woman was killed when her ATV rolled over near South Big Bug Mesa in Mayer Thursday afternoon. Yavapai County Sheriff’s officials say they received two calls at around 4:30 p.m. saying the Polaris side-by-side ATV was involved in an accident. A passerby and his wife arrived at the scene and used two-by-four boards to lift the ATV and pull the woman out from underneath. First responders from YCSO, Walker Fire and Lifeline Ambulance arrived and stabilized the victim, 40-year-old Kimberly Kapp, who had serious internal injuries. She was taken to Yavapai Regional Medical Center where she was pronounced dead two hours later. Her two children, ages four and one, were with her at the time of the accident and were not injured. There are with family members. Sheriff’s officials say the initial investigation suggests Kapp possibly lost control and began to skid to the other side of the road after hitting debris. Officials say it appears she overcorrected the vehicle, which caused it to overturn and land on the driver’s side pinning her. Authorities say there was no evidence of impairment, but it appears that Kapp was not using a seatbelt, or wearing a helmet or other safety devices at the time of the accident. The two kids were in car seats strapped to the back of the ATV and also were not wearing helmets. Though the children were uninjured, it was determined the car seats were improperly installed and secured in the vehicle. Authorities say the kids were lucky they weren’t hurt or killed in the accident.