Feb. 21--The state has "serious concerns" about safety at Oyster Creek, the nation's oldest operating nuclear power plant.

Lisa Jackson, New Jersey's acting environmental commissioner, wants the Nuclear Regulatory Commission to hold a public hearing on those concerns before it rules on the plant's license renewal application. Jackson threatened to hold her own hearing if the federal agency declines to comply.

The NRC, which has sole authority over relicensing, and Exelon, the Illinois-based energy giant that owns Oyster Creek through a subsidiary called AmerGen, oppose a hearing. They argue that the state is worried over nothing.

Jackson's demand falls short of expressing outright opposition to relicensing -- New Jersey officials have no say in the NRC's final decision -- but it nevertheless puts the state in the same corner as a coalition of environmental and citizen groups. That coalition has adopted the name STROC -- Stop the Relicensing of Oyster Creek -- and has enlisted the pro bono aid of the Rutgers Environmental Law Clinic to help it wedge itself into the NRC's years-long and sometimes opaque license renewal proceedings.

Oyster Creek's operating license expires in 2009, but because renewal takes years, Exelon submitted a relicensing application last summer. If approved, it would keep Oyster Creek open until 2029 -- a total of 60 years. The reactor came online in 1969.

The outcome has national implications. Many of the country's nuclear plants, built in the late 1960s and 1970s, are nearing the end of their license periods, and the NRC has approved all 39 renewal applications it has decided on so far. For the first time since the Three Mile Island accident in 1979, U.S. utilities are planning to build new reactors.

Both the state and STROC have filed what the NRC calls "contentions" -- essentially, objections based on specific problems with the plant -- to try to force the federal agency to consider their concerns when ruling on the plant's application.

So far, lawyers for both the NRC and Exelon have challenged those contentions in an effort to avoid delay in the relicensing process.

"I find it curious that the NRC lawyers actually aggressively try to exclude citizens from the process," said Richard Webster, staff attorney at the Rutgers clinic.

Critics of the plant, nine miles south of Toms River, say the agency's criteria for relicensing are too narrow.

"We look at two things," NRC spokeswoman Diane Screnci said. "Whether [plant operators] have programs in place to manage aging equipment and whether continued operation would cause damage to the environment."

A three-judge panel is expected to rule on the contentions by Feb. 28.

At issue is a layer of metal less than an inch thick. It protects the inside of the reactor's reinforced concrete containment area, called the drywell.

In the event of a nuclear disaster, the metal may be the only barrier keeping deadly radiation from seeping to the outside. It also provides structural support for water and steam hoses and control cables that run in and out of the reactor core.

In 1980, Oyster Creek inspectors discovered corrosion on the liner, near its base, in a place where a sand bed was used to support the liner and keep it from buckling.

Water had leaked out of cracks in the reactor vessel head during the plant's biannual refuelings and had collected in the sand.

When technicians hunted for the cause of the water buildup, they found that drains installed when the plant was built in the 1960s were blocked with construction debris. They cleared the debris, scooped out the sand and applied a layer of epoxy over the corrosion.

Technicians continue to monitor the corrosion with ultrasonic testing equipment, said Exelon spokesman Peter Resler. In other words, they use sound waves to gauge the thickness of the metal liner where it's impossible or impractical to eyeball.

Opponents are unhappy with the frequency of those tests and say they shouldn't be confined to spots on the metal that have had corrosion problems.

"If you don't look, you don't find. That's the current motto of Oyster Creek's operator," said Paul Gunter, director of the reactor watchdog project of the Nuclear Information and Resource Service in Washington, D.C.

Gunter fears undiscovered patches of corrosion have weakened the metal, increasing the likelihood that the structure will buckle under its own weight. In that case, Gunter said, radiation might be released and pipes that carry coolant to the core would be crimped or severed by the collapsing metal.

To avoid any chance of this, Gunter wants Exelon to dig up the concrete at the base of the metal liner to check for corrosion.

Adding weight to Gunter's argument was an estimate done by the plant's owner and found in its 2,400-page relicensing application. It said the barrier had a 74 percent chance of failing if the reactor core melted or its fuel suffered damage in an accident.

Resler, however, said concern over a meltdown is misplaced.

"If there were that 1 in 10 million chance of a severe disaster with core damage, any release of radiation would be contained within that structure by a very thick reinforced concrete shell," Resler said, referring to the containment vessel.

The concrete varies in thickness from 4 to 6 feet and is reinforced by steel bars, Resler said.

"It's fully designed to withstand what an anticipated accident would put on it in terms of pressure," he said.

To force a public hearing, relicensing opponents must apply for what's called "intervener status." They must prove to the three judges of the Atomic Safety and Licensing Board Panel that they have a legitimate "contention" with Exelon's application.

The state's contention also cites what it calls the vulnerability of the plant to an aircraft attack and a concern that Exelon relies on a separate company for emergency backup power. Lawyers for both the NRC and Exelon argued that all the challenges were "inadmissible" on the grounds that they were "outside the scope of a renewal proceeding" because they failed "to establish that a genuine dispute exists on a material issue of law or fact."

"The NRC is renowned as being a hostile forum for citizens," said Webster of Rutgers. "It's very hard to get information. It's very hard to really meaningfully participate in the decision-making process."

On Jan. 31, however, a team of NRC technicians discussed in a public conference call their concern that the metal drywell liners of boiling water reactors, like Oyster Creek, ought to be examined for corrosion whenever plant operators apply for license extensions. They were speaking generally, and not specifically about Oyster Creek. Thirty-four of the nation's 103 commercial reactors are boiling-water reactors.

"So here you have on the one hand NRC technical people saying corrosion is a concern, and on the other hand, you have NRC legal people trying to quash any discussion of corrosion," Gunter said. "It's kind of schizophrenic."

Six of the 17 reactors owned by Exelon have received 20-year license extensions. The six Exelon reactors, in Pennsylvania and Illinois, have approval to remain open until 2029 to 2034.

About half the electricity used in New Jersey is generated by nuclear power. Oyster Creek supplies electricity to the equivalent of 600,000 households. New Jersey has three nuclear plants in Salem County. The closest nuclear facility to North Jersey is the pair of reactors at the Indian Point Energy Center in Westchester County, N.Y., 15 miles north of the New Jersey border.

Exelon's annual revenues are $14 billion, and Resler called Oyster Creek "a valued part of our fleet." So much so, Resler said, that Exelon will spend $20 million on the license renewal.

"That's a major investment," Resler said. "We don't make that investment unless we think it's a good one. And we do believe it's a good investment at Oyster Creek."