EE WAS HELPING CHANGING SCREENS AT THE WASH PLANT. THE WORK AREA WAS WET FROM EARLY MORNING DEW WHILE TIGHTENING DOWN THE SCREENS SIDE RAIL BOLTS, THE EE WAS STANDING ON HIS MOTOR DRIVE WITH H IS LEFT FOOT AND THE NEARBY SECTION OF INSIDE HANDRAILING WITH HIS RIGHT FOOT. THE EE S RIGHT FOOT SLIPPED AND HE FELL AND HIT HIS RIGHT LOWER BACK ONT HE HANDRAILING. AS A RESULT, HE FRACTUR