Tennessee Valley Authority's Browns Ferry Nuclear Station near Athens, Ala.

TVA's Browns Ferry has received more safety flags from the Nuclear Regulatory Commission.

The Athens, Ala., electricity plant powered by three nuclear reactors had a preliminary "white" finding -- NRC's least serious safety flag -- extended from one of the reactors to all three, according to NRC spokesman Joey Ledford.

"The "white" finding for all three units was based on an NRC inspection that found plant operators and staff would not have been able to satisfactorily perform newly implemented procedures for safe plant shutdown," Ledford said.

Operators and staff on all three reactor units "were not adequately trained" on the then-five-month-old procedures, he said.

The NRC action also includes a notice of violation from NRC.

Brown's Ferry also has two other "white" flags on individual reactors: one for too many unplanned shutdowns and another for a high pressure coolant injection system that was out-of-service for more than the allowable hours, TVA spokesman Ray Golden said.

One reactor at the plant also still carries an 2011 NRC "red" finding -- the most serious assigned by federal regulators.

That red finding stems from a faulty valve on a TVA reactor shutdown cooling system that went unnoticed for 18 months until it was needed in a routine shutdown. A backup system intended for use only in the event of fire was employed to safely take the reactor off line, according to TVA and NRC documents.

Golden said TVA's concentration on meeting its own and NRC expectations to fix problems that led to the red finding contributed to the utility's newest troubles prompting the systemwide white finding.

"TVA is making improvements in a number of areas at Browns Ferry, including upgrading fire protection," he said. "As part of this improvement effort, changes made in one area may impact other areas at the plant. That is what happened in this case, and we should have been more sensitive to providing the appropriate training."

Golden said TVA has addressed the issue and will work with the NRC to prepare for more federal oversight.

Ledford said the white finding first was noted on one unit in late June when NRC inspectors watched a TVA fire shutdown drill.

NRC assigns four colors -- green, white, yellow and red -- to its inspection and performance findings. Green is safe. White is the lowest safety flag. Yellow signifies moderate safety concerns. Red designates the highest level of concern. The only level behind red is an NRC order to shut down a plant, according to the NRC.

A few months after Browns Ferry received its red finding, TVA also was white-flagged at both Sequoyah and Watts Bar nuclear plants.

The white finding at Sequoyah -- for excessive unplanned reactor shutdowns in about an 18-month period -- has been lifted, according to TVA and NRC.

The white finding at Watts Bar was made for a security problem that neither TVA nor NRC would disclose. That flag also has been lifted, according to NRC's Web site.

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