Entergy finds crack in Vermont nuke steam dryer

Entergy Corp. said recently that workers at its 510 megawatt Vermont Yankee nuclear unit in Vermont, which had been shut for refueling, identified a "minor hairline crack" in the plant's steam dryer. The New Orleans company, the No. 2 U.S. nuclear plant operator, said in a statement that the repairs to the steam dryer "will not affect the length of the outage."

The company does not discuss the expected length of outages due to competitive reasons. The steam dryer was inspected during this outage, in part, because other U.S. plants had identified steam dryer cracking associated with an increase in power output that has been proposed for Vermont Yankee.

Entergy wants to increase the plant's power output by 110 MW, or 20 percent. One MW supplies enough power for 1,000 homes. A spokesman for the plant, Rob Williams, said the company was still waiting for the U.S. Nuclear Regulatory Commission to approve of the power increase.

The NRC was expected to make a decision by this summer, according to a company statement. Refueling outages usually last about a month. The last time the unit, which is on an 18-month cycle, shut for refueling was from Oct. 6-28, 2002.

In addition to the normal refueling and maintenance, Entergy has said it will replace the unit's high-pressure turbine and rebuild the generator, both of which are related to the proposed increase in power output. STEAM DRYER The steam dryer is used to remove moisture from steam produced in the plant's reactor.

The cracks, which Entergy said had "no impact" on nuclear safety, were discovered in an inspection by General Electric Co. , the plant's original designer. To fix the cracks and reinforce the steam dryer, Entergy said two weld sections -- each about three inches long -- were removed and rewelded. The inspection also identified two other hairline cracks the company said will be "monitored in place" during future refuelings. The Vermont Yankee station is located in Vernon, Vermont, about 80 miles north of Hartford, Connecticut.