The Nuclear Regulatory Commission will increase its oversight of Duke Energy’s Oconee power plant near Seneca, S.C., after a leak forced the shutdown of one of its three units.
The NRC cited Duke for a violation for failing to find and fix a crack in a weld on a key safety system. The violation was found during a June inspection.
The cracked weld was in the unit’s high-pressure injection system, which would pump water to cool the reactor core during an accident.
The NRC said the crack was repaired and posed no immediate threat, but it blamed plant officials for not finding the crack before it began leaking.
After a July 31 conference with Duke, the agency classified the violation as “white” or having low to moderate safety significance. White is the second-lowest in a four-color system the NRC uses to classify the safety significance of violations.
The finding means the NRC will conduct a supplemental inspection of the plant to ensure that the problem won’t happen again.
“Duke Energy has taken initial corrective actions at the Oconee plant and the supplemental inspection is an important step in helping us ensure the plant continues to operate safely,” NRC regional administrator Victor McCree said in a statement.
The NRC has cited Oconee for 14 “significant” violations since 2000. Two were classified as having yellow or substantial safety significance, and the rest were classified white.
Oconee began operating in 1973, making it Duke’s second-oldest nuclear plant. Its license expires in 2033.