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Boiling Point

Activists go critical over the waste-storage issue at the Shearon Harris nuclear power plant

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To reach the Shearon Harris nuclear power plant in Wake County, exit U.S. 1 about 15 miles southwest of Raleigh and turn left at the sign for the turkey shoot. The pine trees here are thick enough, and the dwellings rough enough, to be the set for Walking Tall. There's a logging truck on the road, but otherwise nothing's moving--until finally you come to the sign for the plant and turn left again to be jolted by the sight, above the tree line, of its giant cooling tower exhaling steam.

Once again, nuclear power commands our attention, as it did 22 years ago when the accident at the Three-Mile Island reactor in Pennsylvania rocked the nation and burned the image of its cooling tower into our collective consciousness. The nuclear industry was cooked, it seemed. Some 60 plants on the drawing boards before Three-Mile Island were cancelled. Since 1973, in fact, not a single new plant has been ordered in the United States.

Harris epitomizes the industry's standstill. Its owner, Carolina Power & Light Co., planned to build four reactor units there. It built one, and that one--overhauled in mid-course because of TMI--didn't open until 1987, 16 years after the company set it in motion.

But if nuclear power seems like a '70s bad dream, wake up to the facts. There are still 103 reactors in operation in 31 states, and they supply 20 percent of the nation's electric power. Four, including the one at Harris, are owned by CP&L. Indeed, there's a good chance you're using their power right now--46 percent of CP&L's electric generation is nuclear.

Today, the issue is nuclear waste storage--specifically, whether the Harris plant has so much of it, so close together, that an accident of epochal proportions is possible.

All four CP&L reactors, the one at Harris and three elsewhere, generate waste in the form of spent fuel rods--used-up nuclear fuel that remains highly radioactive and lethal. All of this radioactive material ends up at the Harris plant, where it is stored in pools of water designed 30 years ago for short-term decontamination only. Why there? First, because the nation has never built a permanent nuclear waste repository. And second, while only one of the four Harris reactors got built, all four of its waste-storage pools did.

In addition to Harris, CP&L runs two reactors (and two storage pools) at its Brunswick facility in Southport, and a third reactor (and pool) at its Robinson plant in Hartsville, S.C. All three facilities opened before 1977. All of their storage pools have been full up since 1988. By contrast, only two of the four pools at the Harris plant have been used at all, and both of them still have some capacity left--at least, they do by the standards of the Nuclear Regulatory Commission (NRC).

Every time Brunswick and Robinson refuel, pulling spent rods out of their reactor cores, they must make room for them in their own pools by taking out an equal amount of their "old, cold rods"--the ones that have been in the water the longest--and putting them somewhere else. That somewhere has been at Harris, where they arrive via specially equipped railroad cars on a spur that runs right to the pools' edge.

Two years ago, as the first two Harris pools were approaching 80 percent capacity, CP&L applied to the NRC for permission to open up the other two pools. The company considered the application routine--simply more of what it was already doing--and expected approval to take a month. But before it had even submitted the paperwork, CP&L found itself under attack by critics who labeled the whole idea of waste storage in packed storage pools a disaster waiting to happen, and Harris the worst-case scenario.

Harris, the critics pointed out, stood to be the biggest nuclear-waste storage facility in the country unless CP&L was stopped.

The Orange County Board of Commissioners filed a formal challenge with the NRC, and since then the Harris plant became ground zero in a debate with national implications about how dangerous stored fuel rods are, and how best to minimize that danger. The challenge is supported by the Durham County Board of Commissioners and the town governments of Chapel Hill, Carrboro and Hillsborough. A dozen local governments have passed resolutions asking CP&L for hearings, as has U.S. Sen. John Edwards.

The issues are highly technical, but they come down to a question of wet vs. dry--pool storage at Harris versus storage in so-called dry casks made of metal and concrete that could be located at all three plants--Harris, Brunswick and Robinson. CP&L's critics say dry storage is safer.

The company says wet and dry storage are equally safe, and that forcing it to buy dry casks in place of the pools it already has would be a waste of $90 million.

A Bitter BattleCP&L says the dangers from waste storage are "remote and speculative" only. That language is a term of art in NRC parlance--it means something is so unlikely that there's no need to consider it when making policy. The company's critics concede that4

a waste-storage accident is "a low-probability event," but no more unlikely than a reactor meltdown, and with consequences that could be far worse.

In recent months, the fight has gotten bitter. NC WARN (North Carolina Waste Awareness and Reduction Network), an environmental group based in Durham, led pickets to a CP&L shareholders meeting in Raleigh and then started a campaign of civil disobedience to protest the company's refusal to go along with public hearings on the issue. Jim Warren, NC WARN's director, was among a small group arrested for refusing to leave CP&L's doorstep last month. (See "NC WARN members risk arrest out of 'necessity,'" page 23.) Warren calls the company arrogant and blind to the dangers it is creating. "This is a classic case of avoidable risk," he says. "The consequences of a waste-pool accident at Harris could exceed anything the American public has dreamed of."

In retaliation, CP&L "expressed concern" about the protesters' tactics to the Triangle United Way, according to published reports, and the next thing NC WARN knew it had been dropped from the United Way's list of nonprofit groups eligible for its workplace giving campaign. According to news accounts, United Way officials have denied that NC WARN's exclusion resulted from CP&L's complaint. CP&L spokesmen, meanwhile, have accused NC WARN of making things up to distort the problem. "They don't let the facts stand in the way of a good story," says CP&L's Jim Hughes.

That was Hughes' response to Warren's estimate that dry-cask storage should cost CP&L about $29 million more than pool storage over a period of 30 years, not the $90 million more the company projected. Warren acknowledges it was an "armchair" estimate, but adds that he worked as a corporate accountant before turning to environmental activism. He in turn challenges CP&L to show how it arrived at the higher figure.

If NC WARN is the vanguard of the opposition, however, CP&L's real problem is Dr. Gordon Thompson, an Australian scholar by way of Oxford, England, who heads the Institute for Resource and Security Studies in Cambridge, Mass. Thompson, retained as an expert witness by Orange County, says flatly: "A potential for severe accidents exists" at Harris.

Based on his work, Orange County and NC WARN have pushed the NRC to make CP&L's application the subject of a hearing process at which Thompson can testify and CP&L's witnesses can be questioned by Dianne Curran, a Washington lawyer who specializes in nuclear-power issues and who also is working on retainer for the county. Together, their objective is to get the NRC to order CP&L to do a full-blown environmental impact statement that compares the costs and benefits of dry- and wet-storage methods.

David Lochbaum, a nuclear engineer on the staff of the Union of Concerned Scientists in Washington, D.C., has been following the Shearon Harris case from the beginning, including acting for a time as a consultant to Orange County. Lochbaum wrote a 1996 book, Nuclear Waste Disposal Crisis, that decried the federal government's failure to provide a long-term storage facility for spent-fuel assemblies. Lochbaum's thesis is that on-site storage of any kind is risky, but that--given the government's inaction--the risk must be managed. And in general, Lochbaum thinks, dry-cask storage is preferable to storage pools for one simple reason: "Fewer failure modes," he says. "In other words, no movable parts."

With cask storage, once the spent fuel has cooled off underwater for three to five years, it's taken out and entombed in concrete or metal coffins above ground. With enough coffins, it requires only air cooling, Lochbaum says, eliminating any danger that a shutoff of water will lead to disaster.

On the other hand, Lochbaum says, the pools at the Harris plant are safer than most because they're connected directly to backup power systems that come on automatically if primary power is lost. At many other nuclear facilities, backup power must be diverted from some other use. "Harris bothers me less," Lochbaum says. "But it also bothers me that [CP&L] hasn't done a detailed determination of the options. If they did a full evaluation, they might find dry storage would be safer and cheaper, too."

CP&L has resisted that idea furiously, and so far the NRC's staff has sided with the company. But that could change in the next few days. An NRC panel--independent of the staff--is scheduled to meet Dec. 7 to entertain arguments for and against Orange County's effort to force hearings and an environmental impact statement. The NRC meeting, set for 9:30 a.m. in the McKimmon Center on the N.C. State campus, is open to the public. While Thompson won't be heard there, he will be heard at a forum Dec. 6 at Chapel Hill Town Hall, hosted by Orange County. The forum will start at 7:30 p.m.

Meanwhile, NC WARN plans to pump up the volume with a protest rally at the Harris plant Dec. 3, starting at 3 p.m. Warren promises music, the Giant Puppets of Donovan Zimmerman and Jan Berger, and another round of "nonviolent civil disobedience by a predetermined group." (See sidebar, page 25.)

Inside Shearon HarrisYou can drive right up to the front door of Shearon Harris unimpeded. But once inside, the tenor of things changes abruptly. Security is tight. Guards carrying (you're told) nine weapons, including automatic rifles, are around every corner and in front of each of a series of iron gates through which you must pass to enter the plant. Going in, the guards check your credentials. Going out, they observe while machines check you for any hint of radiation on your hands, clothing or gear.

CP&L's CEO, William Cavanaugh III, is a nuclear engineer and a bear on safety, says Ed Wills, environmental and radiation control manager for the plant. But the strict adherence to rules owes as much to the military nature of the complex as it does to science. Nuclear power in the hands of terrorists or saboteurs is unthinkable, which is why Wills and others working at the plant have thought about it and decided it's not going to happen. No way.

They don't mind talking about it. "There are a lot of other places that would be a lot easier to take than this one," Wills says evenly. Information about how many guards are employed at the plant is a secret, for security reasons. The number of employees otherwise is about 600.

Along with CP&L's public relations staff, Wills escorts visiting reporters and public officials who come to see the fuel-handling building, which is where the controversial storage pools are located. The two pools now in use are at one end of the building. Two more, the ones the company wants to use, are at the other end. Each pool is reinforced concrete, 6 feet thick, 40 feet deep and filled nearly to the top with water. Between them is a series of canals, equally deep, that converge into a main channel that links the fuel-handling building to the containment building, and the nuclear reactor itself, next door.

When fuel rods come out of the reactor, they are red-hot with radioactivity and cannot be exposed to air. The canals allow them to be off-loaded under water and remain under water while they're transported on a rail all the way to the storage pools. The rods are zirconium tubes containing uranium pellets. There are 289 rods (arranged 17 by 17) per fuel assembly, 157 assemblies in a reactor at a time. Each assembly measures 13.3 feet tall by 8.44 inches square. They stand vertically once in storage. Specially designed racks receive each assembly near the bottom of the pool and hold it upright, about a foot away from the others, and the same distance off the pool bottom itself. The effect is like a metal egg carton submerged 26 feet underwater.

The four pools at Harris vary in size. The two now in use can hold up to 723 and 2,946 assemblies. The two others would add a combined 4,715 slots. Pool temperature is maintained between 75 and 100 degrees Fahrenheit--higher with new fuel rods installed, cooler once they've been underwater for awhile.

The fuel assemblies must remain underwater for at least three years before they can be exposed to the air. After that, they can be moved to dry storage or left submerged. If submerged, the only requirement is that the water level be maintained at least 8 feet above them. (Thus, the 40-foot depth allows the assemblies to be brought in above the racks and lowered into them with several feet of water to spare.)

There's disagreement between the industry and critics like Thompson over how disastrous it would be if a pool full of hot fuel assemblies were covered by less than an 8-foot water buffer. For one thing, less water means higher temperature, and unless new water is being added, eventually all of it will boil away. Thompson believes that, even before that would happen, an "exothermic chain reaction" would occur--a fire that causes a nuclear chain reaction in the pool. If the fire spread, the result could be a meltdown far worse than any reactor meltdown could ever be, since a reactor holds just 157 assemblies but a full pool might have several thousand.

Wills' response is twofold. Exothermic reaction is an unproven theory, he says. But more important, CP&L's pools will never lose water. Never. "We're designed with a lot of defense-in-depth," he says.

The defenses start with a cooling system powered by the reactor itself. The system carries off water heated up by the fuel roads and delivers cool water in its place. If reactor power is lost, two emergency diesel generators are on line, each running its own "train" of water so that if "Alpha" train fails too, "Bravo" train can take over. If all three fail, there are other water sources in the facility that can be redirected, Wills says. If worst came to worst, Lake Harris itself could be pumped in to flood the building.

Wills has heard all the doomsday forecasts. He rejects them. The pools are monitored constantly for leaks. They do not leak. They can withstand shocks up to and including the worst earthquakes. "We don't feel that there is ... there is no credible event that could empty the pools," he answers finally.

The final stop on CP&L's tour is the control room, where David Corbett, a senior reactor operator licensed by the NRC, heads a crew of five who monitor a vast array of dials and displays. Among them are displays showing water levels in the spent-fuel waste pools and others that show whether the primary cooling system and standby generators are operating normally. "If there was a power outage--if a helicopter crashed into the switchyard out there and there was a total loss of power--we'd be all right," Corbett says. He smiles just a little, and he looks almost amazed to be asked if he's ever seen the pool-water levels drop, even slightly, on his monitors. "I've been here since 1983," he thinks aloud. "I don't remember seeing that."

So saying, Corbett switches on the enunciators, which are supposed to go AAOOGAH if the level moves from Hi/Hi to Hi/Lo, a drop of just 2 feet. "That would get your attention," he says. Lo/Lo would be down 4 feet, or still about 22 feet above the top of the fuel assembly racks.

Corbett is coolly confident that, even if the worst should happen--a reactor-core accident, with a major release of radioactive particles outside the containment building--he and his crew could get through it and maintain the control room. "Alive, healthy and alert," he says. They could let contaminated air out on the downwind side of the plant, fresh air in on the opposite side. And they'd maintain water levels in the pools manually, if they had to, without moving from their post. The automatic system "is a pretty good design," Corbett says. "But we can fill 'em too if we have to."

The Doomsday ScenarioIf CP&L is certain nothing can go wrong with the waste-storage pools, Dr. Gordon Thompson thinks about the uncertainties, and what would happen if a waste pool did go exothermic. "This is a low-probability event as measured by the standards of everyday life," he says. "By the standards of everyday life, we all die eventually. In this instance, we are considering an accumulation of radioactive material in the atmosphere that could render North Carolina uninhabitable for a couple of centuries."

What's more, Thompson says, the chances of a waste-pool accident are about the same as the chance of a severe reactor meltdown. But while the NRC has forced the nuclear industry to analyze all manner of reactor risks, it has so far given it a pass on waste-storage questions, including the issue of dry storage vs. wet.

The level of risk is a basic point of contention between Thompson and CP&L, and one that both sides agree will drive the NRC's decision about whether to require an environmental impact statement. CP&L characterizes the risk of a storage-pool accident as the sum of the risks of a severe reactor accident and a cooling-system failure and a failure of the backup power systems--in other words, it says, seven essentially unrelated events would have to occur simultaneously to cause a pool problem. Thompson, however, sees these events as intrinsically related: A severe reactor accident, he maintains, is likely to cause the other events.

In papers submitted to the NRC, Thompson calls attention as well to the chance that a pool disaster could result from a terrorist attack or a group of saboteurs operating from the inside. "A credible sabotage/terrorism event," he says, "would involve a group taking control of the fuel-handling building, shutting down the pool cooling systems, and siphoning water from the pools." Assuming they could get in, he thinks, the rest would be "comparatively easy."

CP&L maintains its security is equal to any such attack.

The NRC, while it oversees nuclear industry security, takes the position that it cannot estimate the probability of a terrorist incident. Otherwise, though, risk analyses drive the NRC's policy decisions. By appointing a special panel--called an Atomic Safety and Licensing Board (ASLB)--to consider CP&L's application and Orange County's challenge to it, the NRC has signaled that it is at least considering whether its policies on pool storage should change. The ASLB, in turn, ordered CP&L and Thompson--for Orange County--to assess the probability that a severe reactor accident would lead to a waste-pool accident.

A general study of a possible pool-storage accident done for the NRC in 1997 by Brookhaven National Laboratory estimated that the consequences could be as high as 140,000 deaths and $500 billion in property losses. It did not address the question of probability, however.

In NRC terms, risk is the product of consequences and probability, which is why the CP&L-Thompson clash looms so large.

Thompson's argument is that a reactor meltdown, if bad enough ("severe" is another NRC term of art), would cause a major release of radioactive material outside the containment building. Such a release would contaminate the entire plant, including the fuel-storage building, and be accompanied by an explosive force sufficient to knock out all of the power systems on-site.

Restoring them, then, would require personnel to go to work on the plant grounds, where radioactive doses of up to 500 rems would be lethal, or inside non-containment structures like the fuel-handling building, where the doses would be smaller, but still far above the five rems per year that is considered dangerous by the NRC.

Thompson also doubts that the control-room personnel would survive a severe meltdown, as CP&L's people insist. "That will undoubtedly be a point of dispute" before the ASLB, he says.

What makes the storage pools so dangerous, Thompson emphasizes, is that they were designed for short-term decontamination only, not long-term storage. Originally, the idea was that spent-fuel rods would be reprocessed, with the uranium and plutonium isotopes in them recycled into new fuel rods. When the Carter Administration, in the '70s, decided that was too dangerous, federal policy shifted to the idea of a permanent waste facility--somewhere. That plan has gone nowhere, too. Currently, the government's proposed site is at Yucca Mountain, Nev. However, the opposition of Nevada's congressional delegation has stopped it cold so far.

Because there's no place to send the waste, nuclear plants were forced to store more and more spent fuel in their pools, which meant packing them in tighter and tighter. Tighter packing requires racks with special metal plating in between. But even that, Thompson thinks, won't prevent a holocaust if the water level drops too low.

In the scenario he sketches, once a meltdown knocks out cooling power, heat from the fuel assemblies starts to boil the pool water away, resulting in partial or full evaporation in about 10 days. The resulting fission could release more than 700 kilograms of cesium, depending on the age of the fuel assemblies and how quickly they were uncovered. By way of comparison, scientists estimate that the Chernobyl reactor accident in 1986 released 27 kilograms.

What makes this an issue of national importance, according to Union of Concerned Scientists' Lochbaum, is that most nuclear plants in the country, while they've already exhausted their pool space and have been forced to go to dry-cask storage, never winnowed their pools. As a consequence, he says, most of the 103 have storage pools as tightly packed as the ones at Harris. Thus, a ruling on Harris could be applicable to every one of them, he says.

Oddly, Thompson's hypothesis is that more cesium would be released if the assemblies were only partially uncovered than if they were in no water at all, because water below the holding racks would keep air from flowing through and mitigating the damage.

It's that scenario that will be debated at the Dec. 7 meeting. There, the issue will be whether there's enough chance Thompson is right to move to hearings. Thompson himself won't be heard. Only Curran will be allowed to speak for her client, Orange County, in arguing that there are "substantial and material differences of fact" that require witnesses, and cross-examination, to resolve.

According to Hughes, CP&L has submitted 2,000 pages of material to the ASLB in support of its position that Thompson's scenario is so unlikely that no testimony need be taken. "In fact," CP&L says in a statement, "there is a significantly higher probability each year that the Earth will return to the Ice Age than that the sequence of events Orange County has postulated would lead to an accident in the used-fuel facility" at Harris.

The company's not kidding, by the way. It says that its expert, Dr. Edward Burns, estimates the likelihood of a reactor-and-pool accident at three in 100 million per year, whereas "the generally accepted probability of a global return to the Ice Age in a given year is one in 10,000."

Thompson, on the other hand, sees it this way. CP&L's own estimate of a severe reactor meltdown--the NRC requires the company to make one--is one in 100,000. If he's right, and the chance of a pool accident is roughly the same, then with about 100 nuclear plants in the country, we are running a 1-in-100 chance of having a catastrophic nuclear disaster somewhere in the United States every century.

"And the question then," he says, "is why are we running that risk?" EndBlock

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