Open Phase Conditions in Electric Power Systems

U.S. Nuclear Regulatory Commission (NRC) has completed evaluations and inspections of the responses and other actions taken by the licensees of the nuclear power plants in response to the “NRC Bulletin 2012-01: Design Vulnerability in Electric Power System” (Bulletin), relating to open phase condition (OPC) in the plant offsite power system. The NRC staff has concluded that potential adverse impacts on nuclear plant safety due to an OPC in the plant offsite power system has been adequately addressed by the licensees. The NRC staff has approved the actions to be taken by the licensee for Vogtle Units 3 and 4 following commencement of operations and will inspect these actions under the Reactor Oversight Process. As such, NRC Bulletin 2012-01 is closed.

A Federal Register Notice (FRN) was issued on March 6, 2023, in which the NRC informed all holders of operating licenses and combined licenses for nuclear power reactors of the closure of the Bulletin. Details of the OPC topic including a summary of the staff’s actions to address OPC, references to the Bulletin closure letters for the various plants as well as details regarding staff’s actions regarding Vogtle Units 3 and 4, are provided in the FRN.

Page Last Reviewed/Updated Tuesday, April 04, 2023