Federal regulators have cited TVA with three more apparent violations at Watts Bar Nuclear Plant - this time over thousands of parts the utility purchased that are not documented as nuclear-grade quality.
Tennessee Valley Authority officials and engineers then failed to maintain a quality assurance program to test and certify those parts as nuclear grade, according to the Nuclear Regulatory Commission and TVA.
Now TVA must hire a contractor and pay for 30 or 40 experts to backtrack at least 6,200 shipments and purchases of different parts -- some already installed and some dating back to 1995.
What's more, the undocumented parts may not be installed or stored only at Watts Bar, but also at the Sequoyah and Browns Ferry nuclear plants. What began as a Watts Bar issue has been "escalated" to include all of TVA's seven reactors at three nuclear plants.
It was not clear Thursday, and TVA had no estimate, of how much it might cost to check all the parts, ensure their quality and replace any as necessary.
In 1995, the NRC recognized that nuclear operators were having increasing problems finding nuclear-grade parts as the industry's growth lulled in the United States after the 1979 Three Mile Island accident. So regulators enacted rules requiring that parts obtained from non-nuclear-certified vendors must receive special and strict industry testing to be performed and documented by the operators.
But TVA apparently missed the memo.
TVA officials who met Thursday with NRC regulators in Atlanta acknowledged that their engineers didn't notice the new rules and didn't make the change.
TVA spokeswoman Gail Rymer said the nuclear plants are safe and the public is not at risk.
The parts review -- now about 11 percent complete -- has not identified any defective items, according to Joe Calle, TVA's manager for what the agency is calling the "recovery project."
Calle told NRC officials that TVA officials have confidence in the parts based on the utility's historical relationships with the commercial vendors and the specifications of their purchase orders. The quality of the parts is not the problem, he said. Rather, the trouble was in TVA's record-keeping for quality control.
"Latent organizational and programmatic shortfalls within engineering, supply chain and procurement engineering did not account for monitoring or assessing [the] ... commercial grade dedication program weaknesses and industry changes," Calle told NRC experts.
One example he gave was the database TVA used to catalog parts. He said it had drop-down windows for information entry, rather than areas that allowed for more information.
So TVA's procurement engineers "did not always provide sufficient documentation for the critical characteristics" to ensure quality parts. "Neither the software template nor the procedure contains direction for capturing critical thinking and justification," states a TVA slide provided to explain why many parts do not have adequate quality control documentation.
"We created our own perfect storm," Calle told NRC officials.
That quality control testing and documentation would vary from part to part, he said, but in many cases it should involve measuring sizes and testing hardness.
NRC officials Thursday seemed not so sure when Calle said at least one undocumented part has failed, but not because it was not a nuclear-grade part.
"You can't really tell why it failed, because you haven't really investigated it completely, right? You haven't completed all the reviews," countered Richard Croteau, the region's director for construction projects.
"No, we have a long way to go," Calle replied.
NRC inspectors first noticed the problem in a Watts Bar inspection in September 2011. When it was not resolved within a year, regulators in February 2012 handed TVA what is called a "noncited violation" notice.
Then in additional inspections in December 2012, January and February 2013, NRC inspectors decided still more attention was needed, and now the regulators have "escalated" their oversight.
"Based on the results of this ... three apparent violations were identified and are being considered for escalated enforcement action," states a new NRC letter to TVA dated Tuesday.
During Thursday's meeting, Calle and Don Jernigan, TVA's senior vice president for nuclear support, said that of the 6,200 unique parts orders (an order may contain multiple identical items) TVA now has reviewed 728, about 11 percent.
Of those 728, at least one part from each order package is installed already in at least one TVA nuclear plant.
Those reviews, to date, found:
• 374 parts packages were found acceptable as they had been recorded.
• 354 packages were "determined to require critical characteristics reverification, which includes actual testing of items in some cases," according to TVA.
Jernigan told the NRC that TVA will have developed a prioritizing approach for rechecking already installed undocumented parts by April 30, and the utility will complete its "comprehensive evaluation" of all undocumented commercial-grade parts that have been installed between 1995 and 2011 and correct any identified deficiencies by Dec. 31, 2014.
The Watts Bar Unit 2 reactor already is $2 billion over budget, and its completion date has been extended from 2012 to 2015.
Spokeswoman Rymer said the new problems will not drive up the cost or slow construction.
"We anticipate issues with a complex project like completing Watts Bar 2," she said. "The [parts certification] work is being integrated into ongoing activities at the site, and the project remains on schedule for completion by December 2015 and within a total cost of $4 [billion] to $4.5 billion."
Contact staff writer Pam Sohn at email@example.com or 423-757-6346.