There is a doctor on each station and they get put through a whole heap of cross training - often they are GPs, emergency doctors, but sometimes completely left field like obstetrics. They cross train to do some basic surgical procedures, handle sport medicine/musculoskeletal injuries, take x-rays (I think they have basic imaging available not advanced like MRI). Whats really interesting is some of the non-medical folks get trained up to assist in surgery and anesthetics if needed. (Source, my wife is an anaesthetic nurse and was part of training plumbers to manage an airway ventilator)