The operating performance of the Kewaunee nuclear power plant declined in 2007, in part because of a safety finding that resulted in stepped-up scrutiny of the one-reactor plant east of Green Bay.
The Nuclear Regulatory Commission's annual assessment of Kewaunee found the plant operated safely overall.
The owner and operator of the plant, Dominion Resources Inc. of Richmond, Va., is working to address concerns raised by the commission, spokesman Mark Kanz said.
The Nuclear Regulatory Commission uses a color-coded system to rate the safety of nuclear plants. Minor problems are given a green label, with the color indicators escalating to white, yellow or red, which is reserved for the most serious safety problems. Kewaunee was tagged with a yellow finding, or the second-worst rating.
The NRC found "substantial safety significance" from an incident in June 2006, in which Dominion failed to evaluate and repair an oil leak in an emergency diesel generator. The generators are used to operate safety equipment if the plant loses offsite power.
The commission said workers failed to evaluate the leak, and when the emergency generator leaked again two months later during routine testing, the generator was inoperable.
In a statement, the NRC said the company has made strides to address concerns regulators have raised. However, regulators will continue to monitor the plant during regular inspections this year to ensure that Dominion pays close attention in areas such as how well plant workers identify and address problems.
Most of the findings in the NRC report, in particular the diesel generator problem, are "old news as far as today's operations go," said Kanz of Dominion. The Kewaunee plant has gone 13 months without an emergency shutdown, he said, adding, "We have taken dramatic steps in terms of improving our equipment reliability."
At a meeting tonight in Mishicot, regulators will discuss the plant's performance, and Dominion representatives will detail how they have responded to concerns raised by the NRC.
Dominion bought the Kewaunee plant from two Wisconsin utilities in 2005. The plant generates 568 megawatts of electricity, or enough to power more than 280,000 homes.
The electricity is sold back to the plant's former owners, Wisconsin Public Service Corp. of Green Bay and Wisconsin Power & Light Co. of Madison.
Kanz said Dominion plans to file an application with the NRC in the next few months to extend the life of the plant by 20 years. If approved by the NRC, the Kewaunee plant would be allowed to continue running until 2033.
