The Nuclear Regulatory Commission is launching a special inspection at Duke Energy’s Harris nuclear power plant to assess the circumstances surrounding the discovery of a quarter-inch flaw on the plant’s reactor vessel head.
The plant is located near New Hill, N.C., about 20 miles southwest of Raleigh. The plant was shut down on May 15 when further analysis of ultrasonic data gathered during an earlier refueling outage revealed an irregularity about one-quarter inch long near a nozzle on the vessel head. The flaw did not penetrate the vessel head wall and there was no evidence of leakage. Duke Energy has begun the repair process.
“There was no immediate threat to the public or plant workers, but because the discovery is on the vessel head and was not seen in the original review, we are sending specialists from our Atlanta office to further evaluate the issue,” said Victor McCree, Region II Administrator. “The special inspection team will work to analyze and understand all the details.”
The NRC’s resident inspectors at Harris immediately began assessing the incident and are continuing to monitor the plant’s activities. They are being supplemented this week by two specialized inspectors from the NRC’s Region II offices in Atlanta. The team will, among other things, develop a timeline, review Duke’s actions leading up to the discovery of the flaw, examine the previous ultrasonic testing records for the vessel head, evaluate the company’s repair plans and determine if there are generic issues that should be communicated to other nuclear plants.
The on-site portion of the inspection is expected to take about a week and a half. A report documenting the results will be issued within 45 days of the completion of the inspection.