One of the reactors at the Oconee Nuclear Station shut down Monday, a few days after workers found a small radioactive water leak.
B.J. Gatten, a spokeswoman for Duke Energy at the station in South Carolina, said the leak affected the Unit 1 reactor, and remained confined to the plant’s containment building. That building is a steel-lined structure with concrete walls.
Plant operators discovered the leak Friday evening, and they made the decision to shut down the reactor at 6:35 a.m. Monday, Gatten said. The leak was in a system that circulates water through the reactor, she said.
The amount of the leak was not available, but Gatten said it was less than one-tenth of a gallon per minute, and called the station staff’s decision to shut down the reactor “very conservative.”
She said there was no public health threat and no danger to employees and they reported the leak to the Nuclear Regulatory Commission (NRC).
Batten said Duke Energy will need to do a “detailed analysis” to determine how long it will take to repair the unit.
There are two other reactors at the Oconee Nuclear Station, which is on Lake Keowee eight miles north of Seneca.
Since the station began operating in the 1970s, it has generated more than 500 million megawatt-hours of electricity, according to Duke Energy. The Oconee station is one of the nation’s largest nuclear plants, with a generating capacity of approximately 2.6 million kilowatts. This is enough electricity to power 1.9 million homes.
The station’s second reactor has been offline for a while for a scheduled refueling, Gatten said. The third reactor was operating at 100 percent power Monday afternoon.
“We don’t anticipate any problems meeting our customers’ needs,” Gatten said.
Scott Krein, Oconee County’s emergency management director, said officials notified him of the leak “just as a courtesy,” and doesn’t anticipate any danger or health threat because of it.
“We are monitoring it, but we are not overly concerned,” he said.
The reactor leak is the second one at the Oconee Nuclear Station in less than three weeks.
On Oct. 24, the Unit 3 reactor temporarily shut down after a problem in the water system that helps generate electricity.
At the time, a control valve in the plant’s water system caused changes in the flow of water that generates steam to turn the turbines and create power. The reactor was fully operational less than a week later.