The Waterford 3 nuclear power plant in St. Charles Parish, LA, will receive additional oversight from the Nuclear Regulatory Commission (NRC) because it failed to ensure that an exhaust fan designed to cool diesel generators in an emergency would work.
The NRC issued what it called a “white” finding, meaning the infraction ranks as a low to moderate safety risk.
The NRC evaluates regulatory performance at commercial nuclear power plants with a color-coded process that classifies findings as green, white, yellow or red, in order of increasing safety significance. While the Entergy plant, located in Killona, LA, has taken corrective action, the finding still will result in increased inspections and regulatory oversight, the NRC said.
The generators supply electrical power to safety-related equipment under some emergency conditions. The exhaust fan is necessary to keep the generators from overheating, according to the NRC.
If generators overheat, it could result in a meltdown and containment failure. That’s what happened in Japan in 2011, when three reactors at the Fukushima plant suffered heavy damage after a tsunami and earthquake knocked out power. Since that disaster, the NRC required U.S. nuclear plants to evaluate and upgrade equipment and safety plans to reduce the likelihood of damage from overheating and containment failure in the event of a complete loss of power.
The NRC said Waterford 3 officials failed to establish an adequate test program that demonstrated the exhaust fans would perform as expected. Although the plant has alternative means to provide emergency power to vital equipment, NRC officials said the failure to test the fans is unacceptable.
“While the licensee’s failure to appropriately test the equipment in this instance did not have an impact on public safety, we expect licensees to demonstrate through proper testing the reliability of safety equipment to ensure the plant can adequately respond to an event,” NRC Region IV Administrator Marc Dapas said.