Yankee Rowe late 1980s. They knew they had failed fuel. They were doing the fuel offload, picked up an element. While they were moving it, the top of a fuel pin fell off and rolled acres the cavity floor leaving a black trail behind. After draining the cavity, the Cavity Drain Line got up to 175 R/hr......Okay, I have to admit that this isn't the worst screw up I have witnessed, but it is notable.