EE WAS ROOF BOLTING ON UNIT 2. AS HE WAS LOWERING THE ATRS A PIECE OF LOOSE ROCK ROCK FELL FROM BETWEEN THE ROOF BOLTS STRIKING HIS LEFT LOWER LEG. THE INCIDENT CAUSED A FRACTURE TO THE LEFT A NKLE. THE EE IS AWAY FROM WORK AND UNDER THE DR 'S CARE AT THIS TIME. THIS INCIDENT HAS BEEN UNDER INVESTIGATION WAITING MEDICAL INFORMATION CONFIRMING THE INJURY.