EMPLOYEE WAS OPERATING A D10 DOZER PUSHING MATERIAL TO THE LOADER IN THE PIT AREA. HE WAS OBSERVED BY HIS CO-WORKING COMING OFF THE FACE AND HIT THE PIT FLOOR VERY HARD WITH THE DOZER. THE DOZ ER THEN TRAVELED APPROX 75 FT AND STOPPED. EE WAS FOUND IN THE CAB SLUMPED OVER AND BLEEDING FROM A LARGE LACERATION ON HIS FOREHEAD. REQUIRED 11 STITCHES TO CLOSE.