NEW HILL, N.C. (WTVD) -- The ABC11 I-Team has learned of a new problem at the Duke Energy Shearon Harris power plant in New Hill.
The plant was off-line for refueling when a so-called "flaw" was discovered in the reactor head.
The reactor head is the cap to the nuclear reactor that can be removed for refueling and repairs. The "flaw" occurred close to one of the 65 monitoring rods that run through the cap and into the reactor.
Duke Energy officials describe the flaw as a small depression in a welding seam. They say the public was never in danger. Critics aren't so sure.
"The industry has had this problem for a number of years and they haven't been able to figure out how to prevent it from occurring," said Jim Warren, with the nuclear watchdog group NC WARN.
Duke Energy officials acknowledge that reactor heads do, routinely, wear down.
"It's sort of like driving your car," said Duke spokesperson Kim Crawford. "You have to occasionally take it in for maintenance and make some repairs."
Crawford said the head on the Shearon Harris reactor needed similar repairs in 2012 and 2013 and told ABC11 that in 2012, inspectors missed a "flaw" in the vessel head, sparking an investigation which lead to procedural changes.
Crawford wouldn't say what changes were made.
Critics found little comfort in the company's explanation, citing other "flaws" in other reactors around the country.
"It's the cap on the can that helps them superheat water and create electricity," said Warren, "but it serves a really important safety function too. So if you have flaws in that head on the reactor vessel, that's a very serious problem."
"The biggest question," Warren continued, "is how close was that crack from allowing coolant water under great pressure inside the vessel from leaking out of the vessel."