"In the fall of 2001, inspectors with the Nuclear Regulatory Commission were so concerned about possible corrosion at Ohio's Davis Besse Nuclear Power Station  that they prepared an emergency order to shut it down for inspection. But, according to a report  from the NRC inspector general, senior officials at the agency held off – in part because they did not want to hurt the plant's bottom line.
When workers finally checked the reactor in February of 2002, they made an astonishing finding: Corrosive fluid from overhead pipes had eaten a football-sized hole in the reactor vessel's steel side. The only thing preventing a leak of radioactive coolant was a pencil-thin layer of stainless steel.
The Davis Besse incident has resurfaced in the wake of the ongoing nuclear crisis at Japan's Fukushima Daiichi plant. Stories recounting close ties between Japanese nuclear regulators and utilities there have reinvigorated critics who say the NRC has not been an aggressive enough U.S. watchdog."