Officials with the Nuclear Regulatory Commission are asking TVA for more information about the utility's plan to keep flood waters from disabling either Sequoyah or Watts Bar nuclear plants.
In a meeting today between the Tennessee Valley Authority and the NRC, Fred Lyon, a project manager in NRC's headquarters Office of Nuclear Reactor Regulation in Rockville, Md., asked TVA officials why the Watts Bar plant should be allowed to continue operating because not even the temporary dam heightening modifications - a series of sand and crushed stone baskets - are complete.
The series of baskets have gaps in them where roads pass through, TVA officials acknowledged.
TVA Vice President Don Jernigan said the utility has a 27-hour-margin plan, should weather forecasts indicate a catastrophic flood could be possible.
In that plan, Jernigan said, workers would put in place more barriers to seal those gaps, along with making other emergency flood-mode preparations.
Jernigan and other TVA officials said they will get back to NRC about when in that 27-hour period the gaps would be filled.
NRC and TVA plan another meeting to discuss how TVA will prepare for what the nuclear industry refers to as the "probable maximum flood" - a hypothetical flood that would surpass any known local weather occurrence.
Read more in Tuesday's Chattanooga Times Free Press.