USING JACK HAMMER AND AIR IMPACTING ON THE OUTSIDE OF MILL. AT THE END OF SHIFT THE EMPLOYEE HAD PAIN IN HIS LOWER BACK. THE EMPLOYEE WAS GIVEN PAIN MEDICATION AND RELEASED TO FULL DUTY. SEVER ITY OF PAIN INCREASED AND DOCTOR TOOK HIM OFF WORK ON JAN 30, 01 FOR 3-5 DAYS.