TVA says one reactor back online at Sequoyah Nuclear Plant

UPDATE: TVA spokesman Scott Fiedler says that Unit 1 is back online, while troubleshooting continues on Unit 2.

The two reactors at the Sequoyah Nuclear Plant were taken offline early Tuesday, the same day the TVA asked the community to lessen energy use during the heat wave.


PREVIOUS STORY: TVA spokesman Scott Fiedler tells Local 3 News that the TVA has determined the causes which led to both reactors at the Sequoyah Nuclear Plant's Unit 1 and Unit 2 being taken off line early Tuesday.

Fielder said that "Unit 1: We have determined the cause to be a failed computer processor that provides control functions for systems at the plant. Teams have updated the vendor firmware for the component and are working through final startup procedures."

"Unit 2: We have determined the cause to be associated with a failed diaphragm for a Main Feedwater Regulating Valve. This component is part of Sequoyah’s Secondary Plant and located away from the Reactor vessel and fuel. Repairs are ongoing and operators will return Unit 2 to service once the issue has been fully resolved."

PREVIOUS STORY: Both reactors at the Sequoyah Nuclear Plant are offline as of Thursday morning.

The reactors were shut down Tuesday - and have not been turned back on since.

According to a filing with the U.S. Nuclear Regulatory Commission, both reactors were manually shut off by operators when they discovered not enough water was flowing into the steam generators.

The event report says "All safety systems responded normally, and the plant is currently stable" and that there was no impact on the health and safety of the public or plant personnel.

The first reactor went offline just after midnight Tuesday morning. The second was shut down just before 4:00am Tuesday.
 
Several hours later, the Tennessee Valley Authority sent a request to EPB asking EPB customers to limit electricity use.

TVA sent us a statement on Tuesday, attributing the request to the heat wave slamming most of the eastern United States. But that statement did not mention that their Sequoyah reactors were offline.

Local 3 News was told by the TVA that "TVA Sequoyah Nuclear Plant's Unit 1 and Unit 2 came offline early Tuesday morning, June 24 following issues associated with non-nuclear equipment that did not impact employee or public safety. Reactor safety systems performed as designed, and both reactors were safely shut down while teams evaluate the issues. Once the issues are resolved, the units will return to full operation."

It's not yet known when the reactors could resume generating power.

The TVA says that Sequoyah can supply enough power to meet the needs of about 1.3 million homes in the Tennessee Valley each day.