INJURED WAS HELPING CARRY MATERIALS ON AND OFF LONGWALL FACE (WATER, DUKES, MONORAIL, ROCK DUSTPIPE). PERSON REPORTED DISCOMFORT AT END OF SHIFT WHICH GOT WORSE OVERNIGHT. REPORTED CONDITION TO FOREMAN PRIOR TO START OF SHIFT 1/10/00. WENTTO DOCTOR LATER AND COMPANY WAS INFORMED OF HERNIA ON 7/14/00.