UPDATE 1-Entergy to reduce Vermont Yankee reactor to 40 pct

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NEW YORK, Jan 8 (Reuters) - Entergy Corp (ETR.N) said it would reduce the 620-megawatt Vermont Yankee nuclear power station from full power to about 40 percent Thursday afternoon to fix a small water leak in the feed water system.

The feed water system supplies water to the steam generator.

Workers discovered the leak of about 60 drops per minute late Thursday morning on a 24-inch pipe. The company said the water, which is collected in a drain line, is only mildly radioactive.

The company did not say when the unit would return to full service. Electricity traders guessed the reduction would only last a few days.

The company did say this reduction was not related to the leak in a reactor water clean up system valve gasket reported on Wednesday. [ID:nN07486183] Work on the valve gasket is now scheduled for next week.

Vermont Yankee, which entered service in 1972, is located in Vernon in Windham County about 80 miles (130 km) 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.