Flood protection improvements at Oconee Nuclear

The Nuclear Regulatory Commission has found changes made by Duke Energy at the Oconee nuclear plant would adequately protect the plant from a potential failure of the Jocassee Dam. In 2008, the NRC staff issued a letter to Duke requesting information related to external flooding, including the potential failure of the Jocasee Dam, about 12 miles upstream from the plant. There were numerous meetings and conversations between the NRC and Duke, and the detailed flood hazard analysis took two years to complete. In 2010, Duke submitted the flood analysis and the NRC issued a confirmatory action letter documenting the company’s commitments. The Fukushima Dai-ichi accident happened in 2011 and the NRC issued another letter in 2012 requesting additional information on flooding as the agency worked to ensure that lessons learned from the situation in Japan were applied to U.S. plants including Oconee. Duke submitted its flood hazard reevaluation report in 2013 and then a revised flood hazard reevaluation report in 2015. The modifications includ building new or enhanced flood walls and other features as well as moving some power lines and equipment to less flood-prone locations. In April, Duke informed the NRC that the flooding modifications were complete, and a subsequent inspection led the NRC to determine that the company had satisfied the commitments. “The completion of the commitments in the confimatory action letter gives the NRC confidence that the Oconee plant is adequately protected from external floods, including scenarios involving the failure of the dam,” said NRC Region II Administrator Cathy Haney. Haney said the years it took to resolve the flooding issues at Oconee were necessary to ensure that the best analyses were used, that information from the accident in Japan was incorporated and that the plant modifications met all requirements. The Duke letter stating that the modifications were complete is available on the NRC website. The NRC report closing the confirmation action letter is currently available from the Region II Office of Public Affairs and will be available on the website in the next few days.