11/14/02

Oak Harbor, Ohio - The Davis-Besse nuclear plant, devastated by a large rust hole spawned by leaks in its reactor lid, will become the first plant in the nation to install leak detectors intended to prevent a recurrence.

The ultra-precise, German-made instruments can pick up tiny increases in humidity, an early warning that the reactor's vital coolant is seeping out. Such leakage is a major concern for reactor operators and federal regulators because it is a sign that the reactor's heavy steel lid may have dangerous cracks. The coolant itself can pose a corrosion threat, as Davis-Besse learned the hard way.

The Toledo-area plant won't be able to have the detectors in place on the top and bottom of its reactor before its planned restart early next year, however. That's because the probes must be custom-made. Davis-Besse's owner, FirstEnergy Corp., hopes to install them in 2004, during a shutdown in which the extensive repairs and improvements to the plant are to be evaluated.

The Nuclear Regulatory Commission does not require such devices, but its representatives indicated yesterday that they are pleased with FirstEnergy's initiative.

"We'd be very interested in an online leak-rate detection system," said Sam Collins, the agency's senior reactor safety official. Collins, who is based at NRC headquarters near Washington, D.C., attended the monthly meeting where the special NRC panel overseeing Davis-Besse's rehabilitation judges the plant's progress.

Although it's possible the sophisticated monitors could force the reactor to shut down for repairs sooner than if there were no such system, FirstEnergy nuclear division chief Lew Myers said the added safety margin they provide is worth it.

"It's the right thing to do, and I'd like to be the first to do it," Myers said. "If you've got a leak, it's just going to get worse. You might as well go after it."

Myers could not put a price on the monitoring system, but said it is "expensive." The company has estimated the total cost of repairs, improvements and buying replacement power during the nearly 12 months the plant is expected to remain idled at about $400 million.

FirstEnergy officials hope to have the reactor ready for restart in mid-January, although the final decision is the NRC's. Major hurdles remain, however, including finding the source of rust stains on the bottom of the reactor's huge steel vessel, and determining whether the stains are the result of leaks in tubes that carry instruments up through the base and into the reactor core.

Company and NRC representatives are planning to meet at the agency's Rockville, Md., headquarters on Nov. 26 to discuss FirstEnergy's proposal to test for leaks by bringing the reactor up to its normal operating temperature and pressure. Although its uranium fuel will be reloaded for the test, no nuclear reaction will occur because the reactor's control rods will stay inserted in the core. The reactor's coolant-circulating pumps and the natural decay of its radioactive fuel will generate the heat and pressure.

Before that test can occur, the company must make sure the reactor's huge concrete and steel containment building is leak-tight. The containment check is planned for Jan. 8.

Myers said he is "90 percent certain" the instrument tubes in the reactor's base are not leaking, but because of the rusty red deposits the company's contractor found there this summer, the NRC is insisting on tests to confirm there are no leaks.

The NRC's Collins, whose appearance yesterday surprised FirstEnergy managers, is the most senior agency official yet to attend the Davis-Besse meetings. The NRC considers the hole in the reactor's lid to be the most serious breach of nuclear safety since the partial meltdown at Pennsylvania's Three-Mile Island plant in 1979.

Collins, along with others on the special NRC panel overseeing the plant, probed the adequacy of the many changes FirstEnergy officials say they are making in equipment, management and Davis-Besse's "safety culture." Plant workers who have safety concerns are still suspicious of their bosses' willingness to deal with those issues, and are complaining to the NRC three times as often as they are to the company's ombudsman, said panel chairman Jack Grobe.

"You need to take immediate action to regain the confidence of the staff," Grobe told Myers.

Collins also was in attendance to explain why the NRC allowed Davis-Besse to delay a costly shutdown to inspect its lid for cracks.

"We believed, based on the information we received, that it was acceptable for the plant to continue to operate," Collins said. "We did not know of the erosion on the head. If we had, clearly we would have made a different decision."

To reach these reporters:

jfunk@plaind.com, 216-999-4138

jmangels@plaind.com, 216-999-4842