WHILE EE WAS DRIVING HAUL TRUCK INTO THE PIT AREA, HE WENT OVER HIGHWALL IN PLANNED DRILLING AREA, CAUSING TRUCK TO FLIP OVER. DRIVER HAD A MINOR CUT TO HIS LEFT LEG, SUSTAINED WHEN HE UNBUCK LED SEATBELT WHILE HANGING UPSIDE DOWN IN CAB, AND FELL ONTO DASH AREA.