08/30/02

When Davis-Besse nuclear plant workers and managers unwittingly let acid from leaking reactor coolant completely rot two nuts holding a key valve in 1998, the penalty could have stung.

The corrosion, which percolated unnoticed for four months, violated a pair of the Nuclear Regulatory Commission's basic operating rules and could have threatened the plant's safe operation, an investigation by the agency found. The NRC determined that the lapses warranted a $55,000 fine.

But the regulators decided to give FirstEnergy Corp.'s nuclear division a break. The "effective" and "comprehensive" actions that Davis-Besse managers took to stop the acid leak and correct the cause of the damage earned them a pass on the punishment, the NRC ruled.

Actually, though, the nuclear plant's supposed leak repairs and the improvements it promised in its anti-corrosion program were anything but effective or comprehensive, Davis-Besse's owner now acknowledges.

At the same time the NRC was lauding Davis-Besse's newfound corrosion vigilance, plant personnel were ignoring numerous warnings that something much larger than a couple of fasteners was rusting away inside the containment building. These included boric acid residue on equipment throughout the reactor containment building.

And they even included clumps of dried acid on the reactor's lid.

The 1998 incident was a harbinger of a much more serious event that finally came to light this March - an unprecedented hole the size of a hefty paperback book all the way through the reactor's thick metal lid, the result of another long-undetected acid leak. Only a slim steel liner, bulging from the reactor's high-pressure coolant, prevented a major nuclear accident. The plant remains closed as major repairs and investigations continue.

Had the NRC probed deeper four years ago rather than waiving Davis-Besse's fine and closing the case, some critics say, it might have headed off the extensive reactor lid corrosion and a brush with disaster.

Once the agency is satisfied that a reactor operator has proposed proper remedies and begun the fixes, "we may not necessarily do a follow-up inspection" to determine how well the corrections are carried out, said NRC spokesman Jan Strasma.

"In the best of all worlds, yes, we'd want to do that. Hindsight says it would have been nice to pursue it further," Strasma said, but the agency's limited inspection resources and pressing problems at other plants limited what more it could do at Davis-Besse.

The RC-2 event, as the 1998 valve incident has come to be called, "was an opportunity for the NRC to probe a little deeper and see a serious problem," said nuclear engineer David Lochbaum of the Union of Concerned Scientists, a watchdog group that is closely following the Davis-Besse affair. "Had they done it, there's no guarantee it would have led to the discovery of the hole in the reactor's lid. But it's less likely it would have been overlooked."

Said U.S. Rep. Dennis Kucinich, "These new reports are troubling and demonstrate the need to continue efforts to ensure that Davis-Besse is safe before it can reopen. I will be asking the NRC inspector general to investigate these latest findings."

An NRC task force already is weighing the significance of the RC-2 event as part of a larger review of the agency's oversight of Davis-Besse. The nuclear division of FirstEnergy, operator of the Toledo-area reactor, has documented its own failings in the 1998 event as part of a sharply self-critical analysis of overall plant management problems.

The report, as yet unreleased by the NRC or FirstEnergy but obtained by The Plain Dealer, discloses that:

The chronic leaks of acidic coolant that caused two of the eight walnut-sized hex nuts holding the reactor's RC-2 valve to disappear happened again several months after the NRC closed its review in August 1999, satisfied that the company had effectively solved the problem.

The NRC gave Davis-Besse managers credit for resolving the leaking-valve problem, but FirstEnergy's report says the problem's return in 2000 "indicates the ineffectiveness of previous root cause evaluations and preventive actions."

The NRC in its 1999 decision praised Davis-Besse managers for strengthening maintenance workers' training to recognize the harmful effects that leaking coolant could have on metal parts, and for improving corrosion-inspection plans. But the beefed-up training didn't take.

Plant personnel allowed the boric acid that had accumulated on the reactor's lid since 1996 because of coolant leaks to remain and actually increase. Workers in April 2000 used crowbars to pry away some of the inch-thick "lavalike" deposits covering the lid. Managers let them leave what they couldn't reach. An estimated 900 pounds of the stuff had built up by early 2002, contrary to company and nuclear industry standards.

Beneath this blanket, acid ate away at the lid undetected for at least six years. FirstEnergy now acknowledges that its anti-corrosion training was insufficient, and that plant staff didn't apply the lessons from the valve incident to the acid deposits on the reactor's lid.

In the wake of the 1998 incident, Davis-Besse engineers were specifically taught that red or brown acid residue is a sign of rust damage, FirstEnergy's report says. But the training "was less than adequate" in helping personnel recognize that the red and brown on the lid meant corrosion there, too.

A photo from the plant's inspection in April 2000 clearly shows long smears of dried acid and rust on the huge steel reactor lid, but no one figured out that there might be damage under way on the 6½-inch-thick dome.

Using the lessons from the missing nuts, "we should have recognized this situation" with the corroding reactor lid, FirstEnergy spokesman Todd Schneider said. "We are developing a new boric acid control program which will provide a permanent remedy to problems like this. And we are taking steps to ensure that this program will be implemented correctly."

If it had looked more closely at the valve incident, the NRC might also have recognized that the situation was more serious. FirstEnergy's new report shows that:

Davis-Besse workers in 1998 reported "a lack of comprehensive actions" by management to fix the valve. Its leaks were repeatedly documented in 20 repair orders spanning 22 years.

Managers in November of that year ordered an in-depth review, called a "root cause analysis," but only after workers had filed six reports in five months warning that the leaky valve might threaten plant performance.

Davis-Besse's quality assurance manager looked into the matter and reported in January 1999 that the initial response, corrective actions and management attention given to the leaky valve were "inadequate."

When one group couldn't solve the problem, said the 1999 report, "no other organization(s) stepped up" to help.

And when managers gave assignments, "there was confusion among organizations as to what responsibilities they had incurred."

Still, the NRC concluded seven months later that the plant deserved credit for its corrective work and its recent violation-free record.

Plant personnel had "a much greater sensitivity to the effects of [acid corrosion] on plant equipment," the NRC said at the time.

The agency also praised workers for checking more than 500 other bolts on reactor equipment to ensure that they were stainless steel, and for finally fixing the leaky RC-2 valve.

This time around, FirstEnergy promises that the corrections it is making will be better and more thorough than those it attempted after the RC-2 event. Davis-Besse's workers will be more focused on safety, and the plant's all-new management will look at the big picture rather than viewing malfunctions as isolated events.

And the problematic RC-2 valve, as well as many others, will be replaced before the reactor is restarted, Schneider said.

The NRC's oversight also is shaping up to be far more thorough this time. There are five ongoing reviews that will have an impact on when the agency allows FirstEnergy's idled power plant to rumble back to life.

To reach these Plain Dealer reporters:

jmangels@plaind.com, 216-999-4842

jfunk@plaind.com, 216-999-4138