Federal regulators are increasing their oversight of Unit 1 at the Sequoyah Nuclear Power Plant near Chattanooga as a result of the frequency of unplanned shutdowns at the facility.
The Nuclear Regulatory Commission, after its quarterly review of plant performance in October, updated its assessment of Unit 1, which is operated by the Tennessee Valley Authority.
"Overall, the Sequoyah plant is operating safely," said NRC Acting Region II Administrator Len Wert in a statement. "However, these shutdowns point to potential performance issues and we want to ensure that TVA addresses them appropriately."
Jim Hopson, a TVA spokesman, said the utility is taking the NRC feedback seriously.
Sequoyah Nuclear Plant"We've already placed initial corrective actions into place to improve overall performance," he said. "We'll continue to look at that. We'll focus on trying to get Unit 1 back into regular oversight status."
The NRC's evaluation at Sequoyah consisted of a review of performance indicators and inspection results. The NRC cited one trip at Unit 1 in the first quarter this year and three trips in the third quarter.
The NRC said it will conduct a supplemental inspection to provide assurance that the causes of the shutdowns are understood, to identify the extent of those causes, and to ensure TVA's corrective actions are sufficient.
If a plant takes appropriate corrective actions and improves safety performance, the agency returns to its normal, but still extensive, inspection schedule.
Hopson said the NRC wants to ensure TVA is looking to see if there is any underlying common cause to the unplanned shutdowns.
"That's something we're very interested in, as well," he said. "Any additional corrective actions will be put into place."
The NRC review found that Unit 1 crossed the green-to-white threshold for the "unplanned scrams per 7,000 critical hours" performance indicator.
The agency evaluates inspection findings and performance indicators at commercial nuclear power plants with a color-coded system that classifies them as green, white, yellow or red, in increasing order of safety significance. As the significance increases, the NRC heightens the level of oversight for that plant including additional inspections.
Contact Mike Pare at mpare@timesfreepress.com or 423-757-6318.