CHAPEL HILL – The nuclear reactor at Shearon Harris “can be operated safely” after a quarter-inch crack in a reactor sensor was repaired. WRAL reports that a Nuclear Regulatory Commission official confirmed the repair on Tuesday.

The unexpected shutdown of the nuclear plant— just more than 25 miles southeast of Chapel Hill—sparked an on-going investigation by the NRC.

Duke Energy had to take the plant offline on May 15 because of the crack. No radioactive material leaked from the plant, and public health and safety was never in danger, company officials said.

Duke Energy spokesperson Valerie Patterson told WCHL following the incident that Duke Power performed the NRC-mandated inspections in 2012 during the plants scheduled refueling outage.

She says the flaw was discovered during a review of ultrasonic data that showed a quarter-inch crack in the lid on top of the vessel that holds in superheated water under high pressure.