EMPLOYEE WAS WORKING ON THE THROAT LINERS ON #7 ROD MILL, CHIPPING CEMENT WITH A CHIPPING GUN. THE CHIPPING GUN SLIPPED AND THE BLADE OF THE CHIPPING GUN STRUCK THE EMPLOYEE ON THE INSIDE OF HIS LEFT KNEE. INJURY BECAME REPORTABLE ON 8/27/03 WHEN THE EMPLOYEE RECEIVED A DOCTOR'S CARE.