On October 10, 2011, news broke at Davis-Besse that cracking in the concrete containment shield building had been discovered, during breaching operations to install the third lid in a decade atop the problem-plagued reactor. As revealed much more clearly by a photo included in a U.S. Nuclear Regulatory Commission (NRC) report (but not until eight long months later!), that original cracking discovered was actually quite wide. The photo that NRC displayed prominently on its homepage, however, showed cracking that was more difficult to make out.
FirstEnergy and NRC have called such concrete containment cracking “unique OE [Operating Experience].” But at Crystal River, Florida, however, a “self-inflicted wound” proved fatal – containment cracking due to a botched steam generator replacement so severe, the only fix would have been a multi-billion dollar containment replacement. Crystal River was permanently shutdown.