Yesterday, the Nuclear Regulatory Commission issued a determination of substantial safety concerns in a June event at the Oconee nuclear power plant in South Carolina. According to the NRC finding:
Oconee plant employees on June 2 identified that pressurizer heater breakers essential to the operation of the plant’s standby shutdown facility would not have functioned if needed. The standby shutdown facility is designed to be used for reactor cooling during certain accident scenarios, including fires and severe storms where other cooling systems might be unavailable or inoperable.
The NRC assessed the incident as a Yellow alert, the third highest ranking on its scale. A yellow designation means that the incident had “substantial safety significance.” The agency says that finding “will result in increased NRC inspection and oversight of the facility.”