Following a series of safety findings issued at Browns Ferry Nuclear Plant, officials at TVA have been working toward improving a number of issues related to fire protection and equipment reliability.
Site vice president Keith Polson said plant leaders have gone back to 2007 and uncovered more than 1,000 issues of concern at the plant, which have been distilled into five focus areas — fire protection, corrective action program, operator decision making, accountability and equipment reliability.
A main impetus for the improvements stems from a red, or significant, safety finding issued by the U.S. Nuclear Regulatory Commission following the failure of a residual heat removal valve on the Unit 1 redundant fire protection system.
The finding placed Unit 1 in the NRC’s repetitive degraded cornerstone column, and kicked off an intensive three-part inspection, known in the industry as a 95003 inspection.
The first two parts have been completed, though TVA has not indicated to the NRC when it will be ready for the most intrusive and final phase.
Three-week inspection ahead
Months of preparation by both TVA and the NRC will culminate with an inspection lasting about three weeks that will give unrestricted access to about 25 NRC inspectors. TVA officials hope the end result of the inspections will be moving the Unit 1 reactor from the “red” column to “green.”
“What the NRC is doing, is they’re going to come in and we’ll dig down and we’ll find what went wrong,” said TVA spokesman Ray Golden. “We’ll get all that documented, create corrective actions and kill (the problems) dead so it’s not repeated and fleet implemented. At the end of this … the NRC will identify that we’re doing really good stuff, (but) we’ve got to do more. It’s putting us on the record and them on the record and when we get these (improvements) done, we’re back over to green.”
When asked when the plant would give the go-ahead for the NRC to start the final phase, Polson said a date has not been set.
“Our goal is in the middle of November to sit down with our senior team and with other people from corporate to make that decision on whether we’re ready,” he said.
Fire protection at the three-unit nuclear plant is obviously of utmost importance, not only because of the radioactive materials on site, but also from a historical perspective.
A fire in 1975 forced an emergency shutdown and led to sweeping regulations at all nuclear plants known by professionals as Appendix R.
“The valve that didn’t work, that really isn’t the story,” said Preston Swafford, executive vice president and chief nuclear officer for TVA. “For years, ever since the fire at Browns Ferry Unit 1 ... and the rules around fire protection, … we took a minimalist approach. The NRC approved it, but the NRC was less and less comfortable that (Browns Ferry’s procedures) were a viable mechanism. Instead of us taking care of business, we chose not to and stood on where we were at. That set the groundwork for when this valve failed.”
Adopting new standards
TVA officials maintain that the valve’s failure posed no immediate risk to the health and safety of workers or the public, but it did represent a failure of a backup fire protection train.
As part of the utility’s commitment to fire protection improvement, Browns Ferry has committed to adopting standards set forth by the National Fire Protection Association’s Standard 805, which specifically addresses light-water reactor generating plants. TVA plans to submit a License Amendment Request to the NRC by the end of this year or the first quarter of next year to adopt the new standards.
“All other utilities that have committed (to the guidelines) have submitted or will submit the request; we’re tired of that (fire) history,” Swafford said. “We’ve reconfigured the plant, and by the time the NRC approves the LAR, we will be done with the modifications. The plant will now meet the most rigorous fire protection codes in the country … and it will put the fire protection saga behind us. In the end, it’s very beneficial to the plant.”
Polson said TVA has invested funding to replace equipment at Browns Ferry, and that it’s already paying dividends. The Unit 1 reactor recently set a record after being online continuously for 586 days. Unit 2, which had been online 461 continuous days as of Wednesday, set another record.
Browns Ferry was dealt significant challenges on April 27, 2011, when a tornado downed eight of the nine incoming and outgoing power lines from the plant. When that happened, the plant relied on backup diesel generators to safely shut down the plant.
Polson said the plant had eight generators, but one was out of service at the time. The other seven, however, performed as expected.
Swafford said there are plans to build a bunker at the plant that will withstand an EF-5 tornado.
The bunker will not only provide a safe haven for employees, but will also house three mega-watt diesel generators with quick-connect wiring as yet another redundancy system.
Upgraded equipment also extends to the plant’s fire protection plans and being what Swafford refers to as “farmer smart.” The plant plans to purchase diesel pumps that will draw water out of the Tennessee River and into the plant in case of a fire that cannot be controlled by primary and redundant means.
“I’ve had excellent support from (TVA CEO) Tom Kilgore, and I’ve continued to get funding (for Browns Ferry),” he said. “We were at the top and we were one of the lowest-cost nuclear fleets in the country. But when you’re not fixing equipment, it’s not a good thing. We’ve been fixing Browns Ferry for the last several years, and we have two years left to go. We’re two-thirds through our major equipment improvements.”