MINER WAS SWEEPING OFF THE LEDGE WITH LOADER IN PREPERATION OF DRILLING THE LEDGE. THE LOADER WENT OVER THE HIGHWALL AND LANDED ON ITS CAB AND ROLLED TO ITS SIDE. THE REASON FOR THE LOADER GOING OVER THE HIGHWALL IS UNDER INVESTIGATION AT THIS TIME. EE FAILED UA TAKEN AT THE HOSPITAL WHICH MAY HAVE CONTRIBUTED TO THE ACCIDENT.