ATHENS, Alabama — Federal regulators have removed a critical “red” finding from TVA’s Browns Ferry Nuclear Plant, but the plant remains in a state of heightened inspections due to other problems.
The announcement that Browns Ferry, America’s largest nuclear plant, had completed work related to the 2011 red finding that identified a significant safety problem, was made during a public meeting hosted by the Nuclear Regulatory Commission in Athens tonight.
Browns Ferry remains in the NRC’s Column 4, which means a heightened inspection regimen for Browns Ferry’s Unit 1 reactor. Regulators will monitor plant operations, safety culture, maintenance, equipment reliability and work planning. The Category scoring system reflects a number of problems or safe operations over a defined period of time.
Victor McCree, the Atlanta-based regional administrator for the NRC, said the red finding removal shows TVA has made progress, but needs to do more.
“We’ve seen areas of significantly improved performance, but is there still room for improvement? Yes,” McCree said, Browns Ferry’s upgraded procedures and a new approach to addressing equipment reliability. “But TVA didn’t arrive at this point overnight. There were a number of years where they didn’t take care of the plant equipment well enough, they didn’t invest in people, procedures or processes.
“It will take some time to see sustained performance, but they’re on the right track. They need to continue to invest.”
Regulators issued a “red finding” in 2011 after the fall 2010 discovery of a 600-pound valve blocking the primary emergency cooling line at Unit 1 at the plant. TVA cited poor manufacturing, but the NRC found it was TVA’s own inadequate testing, that let the blocked line sit undiscovered for years.
The NRC determined that the broken valve would have prevented TVA from successfully implementing its shutdown procedure at the plant in the event of a fire.
The inspection results reported today indicate TVA has taken the necessary steps to address the issues that contributed to the problem and has a plan in place to prevent it from happening again.
Keith Polson, site vice president for Browns Ferry, said TVA is committed to not only making the improvements called for by the NRC, but sustaining its performance with an improved safety culture, accountability, upgraded procedures and a program that ensures equipment reliability. Polson said TVA is also committed to meeting increased fire safety standards.
Polson pointed that the plant’s three reactors had no problems meeting power demand during the recent snap of bitterly cold weather.
In leaving Browns Ferry Unit 1 in its Column 4 – Column 5 is unacceptable performance – the NRC cited reliability problems related to a high pressure injection system that is central to the plant’s safety cooling system. McCree said the system had problems identified last January in both starting and staying on during testing. The NRC’s grading system faults a utility for the number of hours a given critical system is unavailable.
Browns Ferry was also marked down due to the need to upgrade its diesel generators The eight huge diesel generators that are needed in case of a loss of off-site power. The generators needed significant maintenance and TVA has undertaken that effort. McCree said the program to improve the generators was the right thing to do and will benefit TVA in the long run, but the recorded downtime during the maintenance was also counted against TVA.
Both of those problems fell under the “white finding” category, less serious than a red finding, but multiple white findings can also lead to a plant being placed, or remaining in the Column 4.
McCree said the current Column 4 standing will likely be changed over time as TVA continues to make improvements and the downtime problems associated with the downtime cycle out.
Updated at 11 p.m. to correct TVA column class term.
Article source: http://blog.al.com/breaking/2014/01/tva.html