EMPLOYEE WAS CHANGING OIL ON CAT MOTOR. HE HAD TO GET MORE OIL & AS HE TURNED AROUND HIS RIGHT FOOT HIT THE LITTLE SLOPE WHERE THERE IS A 2"" PIPE ATTATCHED TO WHICH IS A FLAT PIECE OF STEEL HE SLIPPED & HIS LOWER LEG HIT THIS PIECE OF STEEL AS HE FELL. HE HAS A FRACTURED FIBULA.