Warmer water is not harmful

Rutland Herald

August 5, 2003

Entergy Nuclear is committed to building upon the more than three decades of experience Vermont Yankee employees have protecting the waters of the Connecticut River. It not only makes good business sense, but it also fulfills our mission to safely produce electricity with minimal environmental impact at all of our plants across the country.

Our ongoing river studies are now the most extensive, long-term studies of the health of the Connecticut River conducted by any organization. We provide that collected data annually as part of our regulatory requirements to state and federal agencies, along with many other academic and environmental organizations, which share our stewardship of the river.

The plant withdraws water from the river to cool steam from the turbine generator which produces electricity for Vermont and the rest of New England. In the process, the river water is warmed but never comes in contact with the plant’s nuclear reactor.

Vermont Yankee would like to increase plant efficiency and produce more electricity for consumers by proposing to change the permit that regulates our use of the river for cooling. We presently have an application before the Vermont Agency of Natural Resources, the regulatory body that issues the permit and oversees our continued compliance.

The ANR permit regulates the plant’s discharge of heated water by measuring the river’s constantly changing upstream temperature. As the upstream temperatures get naturally warmer over the summer, a lower temperature limit is applied to the plant’s cooling water as it is returned to the river. Vermont Yankee must adjust to those temperature variances through the use of cooling towers that use evaporation to cool down the water before it is returned to the river.

In the current application, we propose to raise the downstream temperature limits by one degree in the summer months but only when the river is less than 78 degrees. We have presented to the ANR a large amount of information supporting conclusions based on our long-term environmental studies and computer modeling programs. We believe there is a sound scientific basis that a slight change in the current temperature limit will not adversely affect the river environment.

It the past, environmental river studies have supported Vermont Yankee in similar permit change requests. Beginning in 1978, the ANR granted changes to the permit to allow reduced wintertime cooling tower operation and later reduced summertime cooling tower operation beginning in 1990.

Our proposal to ANR would produce an environmental benefit: By returning slightly warmer water with less evaporative cooling, Vermont Yankee would be able to return more water to the river and its ecosystem. This is particularly important when river flows are low due to the weather or activities of the river’s hydro dams.

We’re very proud of the fact that, in all the years that Vermont Yankee has been operating and monitoring the river, no environmental change due to the plant’s operation has been detected.

Entergy Nuclear recognizes the Connecticut River is a sensitive environmental asset and even a very small temperature limit change, such as one degree, must be carefully scrutinized. That scientific process is under way at the ANR.

Entergy biologists and environmental scientists are working to ensure that ANR regulators have the information they need to make the best decision on our request. I can assure you that Entergy Nuclear Vermont Yankee will continue to focus on plant operations with safety as the highest priority and a continuing strong stewardship for all aspects of the environment of the Connecticut River valley.

Jay Thayer is site vice president of Entergy Nuclear Vermont Yankee.