A D-9 DOZER WENT INTO A SURGE PILE OF COAL AT 2 NORTH. A MISCOMMUNICATION OF HAND SIGNALS LED TO THE DOZER OPERATOR MISTAKENLY THINKING THAT THE WRONG FEEDER WAS RUNNING. THE DOZER OPER. WAS U NINJURED BY COULD NOT OPEN THE DOORS OF THE DOZER AND RESISTED ATTEMPTS TO BREAK OUT THE WINDSHIELD FOR ESCAPE.