EMPLOYEE WAS MUCKING WHEN A ROCK FELL FROM THE BACK. IT STRUCK HIS HARD HAT AND THEN HIS ARM. HE DID NOT SEEK MEDICAL ATTENTION UNTIL 11/27/00. HE WAS PLACED ON RESTRICTED DUTY FOR 11/28 29 & 30 WHICH MADE THIS A MEDICAL REPORTABLE INCIDENT. RESTRICTION WAS FOR LIFTING WITH LEFT ARM.