INJURED AND OTHER EE WERE MANUALLY CLEANING TANK 36. INJURED HAD POSITIONED ONE END OF AN 8 FT LONG 4 BY 4 INSIDE OF THE BOBCAT BUCKET AND THE OTHER INTO THE TANK BOTTOM, AS HE RAISED THE BUCK ET, INJURED HAD LEFT HAND ON HYDRAULIC LIFT ARM.AS THE ARM RAISED, HIS LEFT RING FINGER WAS CAUGHT BETWEEN THE ARM AND THE BOBCAT CAB.