After a forced shut down for two weeks last summer because its cooling water was too warm, Connecticut’s nuclear plant asked federal regulators for permission to use warmer water.
In an application submitted to the U.S. Nuclear Regulatory Commission (NRC), Millstone Power Station asked to use water at 80 degrees to operate two units. The change should prevent a plant shutdown during severe hot weather periods, Millstone said in its application.
One of the Waterford station’s units had to shut for nearly two weeks last August because water was warmer than the 75-degree limit. It was the first in the United States caused by rising water temperatures.
The NRC issued an “emergency license amendment,” allowing Millstone, a subsidiary of Dominion Resources Inc., to use an average temperature of several readings.
Water cools key components of the plant and discharges back into the sound. The water’s temperature was averaging 1.7 degrees above the 75-degree limit last August, triggering the shutdown.
Permission to pull in water as warm as 80 degrees “gives us more margin,” Millstone spokesman Ken Holt said Tuesday.
“We would not have shut down if we had the 80-degree limit,” he said.
But because this past winter and the spring have been cooler than the previous year, the Millstone may not need to use water warmer than the current limit.
Neil Sheehan, a spokesman for the federal agency, said that due to the colder winter, hot water will be less of a concern this summer than last year.
A decision by the agency is not due until 2014.