THE INJURED WAS OPERATING A RADIO REMOTE CONTROLLED CONTINUOUS MINER TO CLEAN UP A ROOF FALL. HE WAS POSITIONED OUTBY THE BOOM OF THE MINER AND WHILE CUTTING AND LOADING OUT THE ROOF ROCK FROM THE FALL A VOLLEYBALL SIZE ROCK WAS THROWN FROM THE CUTTING HEAD STRIKING HIM ON THE RIGHT SHOULDER CAUSING SWELLING AND A CONTUSION.