EW was operating 336F#1 CAT excavator with rock breaker. EE was found unconscious by co-worker #1 at approx. 2:00PM. They called coworker #2 for assistance coworker #2 arrived at approx. 2:06PM and they got EE out of excavator. Coworkers began CPR. An ambulance was called at 2:11PM and arrived at approx 2:30PM and crew took over. Ambulance left the site with EE at approx. 3:00 PM.