TVA Ends 'Unusual Event' Declaration With Restoration of Offsite Power Supplies at Browns Ferry Nuclear Plant
May 3, 2011
ATHENS, Ala. — The Tennessee Valley Authority on Tuesday announced the termination of a "notification of unusual event" at the Browns Ferry Nuclear Plant, which began five days earlier when severe storms damaged power lines near the facility.
The "notification of unusual event," ended at 8:50 p.m. CDT on Monday, May 2, was declared on Wednesday, April 27, at 5:01 p.m. CDT when a partial loss of off-site power, resulting from the series of storms and tornadoes in northern Alabama area, prompted activation of diesel generators to provide backup electric service to the plant. At that time, the plant's nuclear reactors safely shut down as designed.
Throughout the severe weather and its aftermath, the nuclear plant has been kept in a safe shutdown condition with no impact to the public or plant employees. The three reactor units at Browns Ferry remain offline while repairs continue to the region's high-voltage transmission system, which is needed to transmit electricity from the plant to customer points.
TVA emergency response centers that had been operating at TVA's operational center in Chattanooga and at Browns Ferry as a result of the "notification of unusual event" were being deactivated Tuesday. The notification of unusual event is the lowest of four levels of nuclear plant emergency classifications defined by the Nuclear Regulatory Commission. In order from least serious, the classifications are: unusual event, alert, site area emergency, and general emergency. An unusual event is defined as a disruption of normal operations with a potential for more serious issues.
"It is important to note that when the storms hit, the reactors and safety systems at Browns Ferry performed as designed, immediately putting the plant in a safe shutdown mode and providing the backup power needed to keep conditions safe for employees and the public," TVA Chief Operating Officer Bill McCollum said. "The plant was designed to withstand weather conditions far more severe than those that occurred last week. The plant's equipment and staff worked well in handling this event."
The Tennessee Valley Authority, a corporation owned by the U.S. government, provides electricity for utility and business customers in most of Tennessee and parts of Alabama, Mississippi, Kentucky, Georgia, North Carolina and Virginia – an area of 80,000 square miles with a population of 9 million. TVA operates 29 hydroelectric dams, 11 coal-fired power plants, three nuclear plants and 11 natural gas-fired power facilities that can produce about 34,000 megawatts of electricity, delivered over 16,000 miles of high-voltage power lines. TVA also provides flood control, navigation, land management and recreation for the Tennessee River system and works with local utilities and state and local governments to promote economic development across the region. TVA, which makes no profits and receives no taxpayer money, is funded by sales of electricity to its customers. Electricity prices in TVA's service territory are below the national average.
Ray Golden, Chattanooga, (423) 751-8400
TVA Media Relations, Knoxville, (865) 632-6000