WHILE DESCENDING THE STAIRS IN THE HYDRAT PLANT. EE S FOOT SLIPPED ON THE BOTTOM EE THEN FELL FORWARD ONTO THE HYDRATE FLOOR. HE DID NOT FEEL ANY PAIN AT THAT TIME. ON 12-9-03 HE DID FELL A DU LL PAIN IN THE MIDDLE OF HIS BACK. THE PAIN IS STILL THERE AS OF TODAY 12-11-03.