published Friday, January 6th, 2012

Nuclear review raises questions

Photo by Contributed Photo /Chattanooga Times Free Press.

LOCAL NUCLEAR STORES


TVA stores spent fuel and fuel rods in pools at all three of its operating plants. Little has been transferred to dry cask storage. The wastes include:

Sequoyah

1,174 metric tons, including

• 796 in pool storage

• 378 in casks

Watts Bar

317 metric tons

• All in pool

Browns Ferry

1,771 metric tons

• 1,468 in three pools

• 303 in casks

Source: TVA

Nuclear regulators appear to be edging closer to cracking down on how nuclear power plants store about 3,300 metric tons of spent fuel in the Chattanooga region, and a local anti-nuclear group is claiming at least some of the credit.

What's unclear is how quickly the Nuclear Regulatory Commission will move, and how much it will cost utilities such as TVA. The federal utility's three operating nuclear plants have at least three-quarters of its highly radioactive spent fuel in cooling pools on-site.

Whatever the cost, it will be less than cleaning up a nuclear accident, said David Lochbaum, a former TVA nuclear reactor operator and a former Nuclear Regulatory Commission training instructor.

"The cost at Fukushima is being estimated at $54 billion now, and it could go higher. We're living on borrowed time if we have all these spent fuel rods piling up in pools," said Lochbaum, who directs the Nuclear Safety Project for the Union of Concerned Scientists.

He said his and other groups hope for compromise from the NRC, which has been looking at proposals to improve nuclear safety at the nation's 104 commercial reactors for at least a decade.

The triple meltdown in March at Japan's Fukushima Dai-ichi Nuclear Plant after a 9.0 earthquake and tsunami is now spurring those reviews. The Union of Concerned Scientists and U.S. anti-nuclear groups-- including a Southeast one called Blue Ridge Environmental Defense League -- have asked regulators to act swiftly to improve safety.

The Defense League's petition, filed April 13, even sought to shut down GE reactors similar to those at Fukushima, including Browns Ferry Nuclear Plant near Athens, Ala.

This week in the Federal Register, the NRC denied the shutdown petition. But the agency said it will consider moving spent fuel to safer storage, and reviewing reactors' "hardened vent" and filter systems, earthquake-rated designs and backup power systems.

The NRC told the groups it already was reviewing similar recommendations from its own July task force report of lessons learned from the Fukushima disaster.

The response states the NRC will act "within a reasonable time," which agency spokesman Dave McIntire measured in years.

"We're looking probably at two years at least to resolve the various issues in the petition and close it out," he said. "That may seem like a long time, but this will involve working with licensees and ensuring that they implement any changes stemming from this before we close out the petition."

Costs and Concerns

Fixes at nuclear plants rarely cost less than millions of dollars, but Nuclear Energy Institute spokesman Mitch Singer said the industry trade group has no estimate of the cost for the additional safety measures now under consideration.

"It will be some time before we know that," Singer said.

Locally, TVA spokesman Ray Golden said he couldn't provide any specific cost estimates either. He confirmed that dry casks to hold spent fuel cost about $1 million each and the U.S. has two supplier companies. One cask holds 10-15 metric tons of waste, a fraction of what is in TVA's five spent-fuel pools.

Golden said the federal utility that operates six, and soon seven, reactors at three nuclear plants in Tennessee and Alabama already has taken other actions. That includes adding backup power so cooling water pumps, valve switches and other emergency systems function even when the lights go out.

But the utility is waiting on other issues, such as possible seismic refits, to see what NRC's finals rules will be.

"We don't want to do work and then have to do it again [if regulations require more]," Golden said.

Shortly after the Japan accident, a shelved NRC recalculation of earthquake risks for plants was sorted and analyzed by msnbc.com.

The analysis found Sequoyah Nuclear Plant's twin reactors in Soddy-Daisy have the nation's fourth-highest earthquake risk when looking at U.S. Geological Survey fault research updates since the 32-year-old plant was licensed.

At Sequoyah, about 17 miles north of Chattanooga, the chances of an earthquake causing core damage at each reactor are 1 in 19,608, according to the risk assessments. The chance a local resident will be struck by lightning is about 1 in 500,000, according to the National Weather Service.

When Sequoyah's two reactors were licensed in 1980 and 1981, the plant's risk for quake-induced core damage was 1 in 102,041. TVA officials have said Sequoyah was designed to withstand motion that equates to a 5.8-magnitude quake.

The msnbc.com figures show Spring City's Watts Bar Nuclear Plant, licensed in 1996, has the 14th-highest quake risk among the nation's 65 operating plants.

There, the chance for reactor core damage is 1 in 27,778, according to the report. TVA says Watts Bar also was built to withstand a 5.8 quake.

At Browns Ferry, licensed in the 1970s to withstand a 6.0 quake, the odds are 1 in 185,185 in reactors 2 and 3. Reactor 1's risk is 1 in 270,270.

On Aug. 23, a magnitude 5.8 earthquake rattled the East Coast and shut down the North Anna nuclear facility near the quake's epicenter in Mineral, Va.

The quake, larger than the plant was designed to withstand, forced North Anna's two reactors into automatic shutdown, but did not cause a nuclear accident.

Two days later, the NRC announced a plan to provide nuclear plants with a seismic analysis software tool and require all reactors to reassess their earthquake risks.

After North Anna's operator, Dominion Virginia Power, spent more than 100,000 hours and $21 million in inspection, testing and evaluation, NRC OK'd the plant's restart on Nov. 11.

But outside the plant, the quake jolted out of place 25 of 27 spent fuel casks on one of two concrete pads. Each cask held 32 fuel rods, officials said.

Dominion spokesman Richard Zuercher said the casks remained safe and intact.

"They are designed not to fall over, and they didn't fall over," he said in the week after the quake.

Sensors designed to detect leaks of helium gas, which fill the casks, indicated no leaks, Zuercher told reporters at the time.

On North Anna's second storage pad, 26 newer casks did not shift, but some concrete flaked off the outside of the newer casks, which sit horizontally rather than vertically like the older casks.

Robert Alvarez, a nuclear waste storage expert from the Institute for Policy Studies, said the quake pointed out a need.

"This indicates that reactors that have these dry casks in these earthquake-prone areas, they're going to have to do more to protect them from ground motion. One thing is to bolt them to the pads. And that's not a Home Depot-type job," Alvarez told the Washington Post.

Prioritizing

Browns Ferry, with its three spent fuel pools elevated several stories high and in the same secondary containment areas as the plant's three reactors, is the Fukushima plant's twin. Lochbaum argues that makes it the local plant most in need of quick action.

If an accident happens there or at the other 21 U.S. plants of that design, both the pools and the reactor are compromised, he said. The elevated pools are more difficult to supply with cooling water, he said, recalling the helicopters in Japan trying to drop water into the pools' blast-ripped roofs.

As for the hardened vents, Golden said TVA already had taken steps to make its plant venting systems more durable even before the Fukushima accident. The utility since has taken steps to ensure there are more alternate ways to control mechanical valves and switches in them.

Golden said there still is a question about efforts made to manipulate the vents at the Japan plants.

"They may have waited too long to use that venting and filter system," he said.

Environmental groups continue to be concerned about the viability of the vent systems' filtration -- or what they call the lack of it.

Louis Zeller wrote the petition to NRC for the Blue Ridge Defense League. Kevin Kamps is with Beyond Nuclear, a national coalition effort to "Freeze Our Fukushimas."

Both said their groups are pleased that NRC accepted at least some of their petition requests.

"Every community living in the shadows of these reactors [like Browns Ferry] with a rooftop high-level radioactive waste dump wants the emergency power systems installed now," said Kamps.

about Pam Sohn...

Pam Sohn has been reporting or editing Chattanooga news for 25 years. A Walden’s Ridge native, she began her journalism career with a 10-year stint at the Anniston (Ala.) Star. She came to the Chattanooga Times Free Press in 1999 after working at the Chattanooga Times for 14 years. She has been a city editor, Sunday editor, wire editor, projects team leader and assistant lifestyle editor. As a reporter, she also has covered the police, ...

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