EMPLOYEE WAS HOLDING A PIECE OF METAL THAT WAS BEING WELDED TO A BUCKET. A LOOSE FIREBALL FROM THE WELD GOT DOWN INTO HIS SHOE. THE FIREBALL BURNED THROUGH EMPLOYEES SOCK AND INTO HIS SKIN. DI VISION OFFICE WAS NOT NOTIFIED UNTIL 9/19/01 OF EMPLOYEE'S INJURY. EMPLOYEE DID NOT SEEK MEDICAL TREATMENT UNTIL 9/19/01 WHEN PLANT MANAGER INSISTED HE GO TO DOCTOR.