America’s Worst Nukes

Location: Joliet, IL

Owner: Exelon

Near-miss: Poor design caused repeated floods – including one involving 12,000 gallons of water – in buildings with safety equipment, causing electrical shorts; allowed vented steam to rip metal siding off containment walls. Plant owner knew about several problems but failed to correct them, leading to a near-miss.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

Location: Southport, NC

Owner: Progress Energy

Near-miss: Inadvertent discharge of toxic halon gas, a fire suppression agent,
prompted control room operators to declare an Alert, the third-most-serious of four emergency classifications. Response was delayed because workers didn't know how to operate the computer systems that told offsite workers to report to emergency-response facilities.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

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Location: Annapolis, MD

Owner: Constellation Energy

Near-miss: A leaky roof allowed rainwater to short out electrical equipment. One reactor automatically shut down. A worn-out protective device that workers had not replaced because of cost-cutting efforts allowed electrical problems to trigger an automatic shutdown of a second reactor. Investigation found that roof leakage had been a recurring problem since 2002 and the company had knowingly tolerated it. Workers had responded to one leak  "by covering the panel with a plastic sheet and catching the leakage in a bucket."

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

Location: Rock Hill, SC

Owner: Duke Energy

Near-miss: Security problems prompted NRC to investigate. Details of problems, causes and fixes not publicly available.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

• Read Jeff Goodell on 'America's Nuclear Nightmare'

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Location: Crystal River, FL

Owner: Progress Energy

Near-miss: Workers severely damaged concrete reactor containment walls when they cut a hole to replace steam generators, a mistake that cost more than $500 million to repair. Union of Concerned Scientists report asks: "Why didn't the company do [its] homework before embarking on this ill-fated experiment, and why did the NRC allow it to happen?"

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

Location: Toledo, OH

Owner: FirstEnergy

Near-miss: Cracks found in metal nozzles for mechanism in replacement reactor vessel head, caused by excessive temperatures which workers failed to track accurately.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

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Location: San Luis Obispo, CA

Owner: Pacific Gas & Electric

Near-miss: Reactor operated for nearly 18 months with vital emergency systems disabled, owing to "a misguided fix" of valves that wouldn't open fast enough, leading to an even larger problem, which tests failed to detect.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

Location: Dothan, AL

Owner: Southern Nuclear

Near miss: A replacement pump had a part with a manufacturing defect, producing excessive vibration levels that caused the pump to fail.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

• Read Jeff Goodell on the Gulf oil spill, one year later

Location: Omaha, NE

Owner: Omaha Public Power District

Near-miss: Pumps in an emergency water  system failed repeatedly over several years, but the plant owner failed to identify the cause.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

Location: Florence, SC

Owner: Progress Energy

Near-miss: 1) On the 31st anniversary of Three Mile Island, this event replicated nearly all the problems that caused that meltdown: bad design, poor maintenance of problematic equipment, inadequate operator performance, and poor training. An investigation found numerous problems in many areas over many years. The Union of Concerned Scientists report: "There is simply no excuse for the fact that the company and NRC had not detected and corrected at least some of these problems before this event." 2) The same problems caused this reactor’s second near-miss in six months.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

Location: Newport News, VA

Owner: Dominion Generation

Near-miss: After an inadvertent shutdown of one reactor, an overheated electrical component caused a fire began in the control room. The same thing had happened in another reactor six months earlier.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

Location: Burlington, KS

Owner: Wolf Creek Nuclear

Near-miss: Seven hours after the reactor shut down automatically because of a problem with the electrical grid, an NRC inspector found water leaking from a cooling system. Although an internal study in 2007 had predicted something along these lines, and a leak had actually occurred after a reactor shutdown in April 2008, the owner had taken few steps to correct the problem.

Source: Union of Concerned Scientists, The NRC and Nuclear Power Plant Safety in 2010

• Read Jeff Goodell on 'America's Nuclear Nightmare'

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