UPDATE 1-Entergy to keep Vermont Yankee reactor at full power

(Updates with company comment, background)

NEW YORK, Jan 7 (Reuters) - Entergy Corp (ETR.N) plans to keep the 620-megawatt Vermont Yankee nuclear power station at full power when it works on a leaking valve gasket on a four-inch pipe in the reactor building over the next few days, a spokesman said Wednesday.

The company said in an email it would enclose the valve with a specially designed clamp and inject a sealant to stop the leak.

The company said it decided to fix the valve now, rather than wait until the next refueling outage, based on a conservative operating philosophy.

The last refueling outage occurred in October and November. As the unit is on an 18-month refueling cycle, electricity traders said the next refuel would likely occur in spring of 2010.

Vermont Yankee, which entered service in 1972, is located in Vernon in Windham County about 80 miles north of Hartford, Connecticut.

Separately, Entergy is waiting for the NRC Commissioners to decide on its application to extend the plant's original 40-year operating license for another 20 years. Entergy filed the application in January 2006.

It usually takes the NRC about 22 months (November 2007) to make a decision on a license renewal without a hearing and about 30 months (July 2008) with a hearing.

In November, the NRC's Atomic Safety and Licensing Board said it was OK with the license extension but wanted Entergy to perform additional analysis on the reactor vessel nozzles before the NRC grants the license extension.