May 25 - McClatchy-Tribune Regional News - Patricia Daddona The Day, New London, Conn.



Millstone owner Dominion has fixed a malfunctioning valve in a steam generator at the Unit 2 reactor that led to an unexpected manual shutdown over the weekend.

Dominion, the parent company of Dominion Nuclear Connecticut, which owns Millstone Power Station, was in the process of restarting Unit 2 on Monday. The Unit 3 reactor, which emerged last week from a refueling outage, has continued to operate.

During the incident Saturday, a feedwater regulator valve in one of two steam generators was opening and closing more often than it had in the past, according to Steve Shaffer, a senior resident inspector for the Nuclear Regulatory Commission who is stationed at the plant, and Dominion spokesman Richard Zuercher.

The valve provides water to the steam generator, which converts heat to steam to help produce electricity.

 Operators took manual control of the valve, which was operating sluggishly, Saturday afternoon, and then it failed to close when prompted, Shaffer said. At 4:45 p.m. Saturday, Dominion took the unit offline in a manual "trip," or quick, forced shutdown, said Shaffer and NRC spokeswoman Diane Screnci.

Since then, Dominion has replaced two "positioners," mechanical controllers that control the movement of the valves -- the one that malfunctioned and another as a precaution, Shaffer said.

The faulty positioner is being analyzed, he said.

The incident posed no threat to public health and safety, Screnci and Shaffer said.

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