NRC Gives OK for Restart of Damaged North Anna Nuclear Plant

North Anna Nuclear Generating Station (photo: dougward)

In what feels like a Friday news dump that goes to 11, the US Nuclear Regulatory Commission has given its approval to restart Dominion Virginia Power’s North Anna nuclear power facility. The decision came late in the day on a holiday–Veterans Day, 11/11/11.

As previously noted, the reactors at North Anna scrammed during the Mineral, VA earthquake of August 23. It was later shown the power plant sustained shaking well beyond its design criteria. Several spent fuel storage casks moved one to four inches, and other storage containers showed what was termed cosmetic damage (namely, cracks), but plant operators contend that the nuclear reactors sustained no “functional” damage.

What constitutes “functional” now remains to be seen. The fact is there was no official protocol–no “checklist”–for evaluating a nuclear facility after it experienced a seismic event such as this. The NRC’s inspectors have essentially been inventing that inspection regime on the fly as they surveyed the North Anna plant. Dominion has been pressing for permission to restart since shortly after the quake.

Of concern, beyond the cracks and dancing dry casks, has been the integrity of the containment buildings and, more specifically, the pipes and couplings that ensure that the reactors can be properly cooled once the cores are allowed to again heat up. Questions about the state of underground pipes were expressed right after the earthquake by watchdogs such as Paul Gunter, and those same buried pipes were cited as recently as last week when explaining the ongoing delay to the restart OK.

North Anna’s reactors were initially thought to have shut down when the cooling systems lost power from the electrical grid, soon after the Virginia quake. Three backup diesel generators provided power to the safety systems until power could be restored (a fourth generator failed). Later, however, it was discovered that the shaking itself caused the reactors to scram–a fast emergency shutdown sometimes compared to slamming the brakes on a speeding car.

How the NRC and its inspectors resolved questions about what constituted a passing grade after a never-before-seen event remains to be seen. Until then, it appears the NRC will do the regulatory equivalent of keeping its fingers crossed:

Eric Leeds, director of the NRC’s Office of Nuclear Reactor Regulation, said in a statement. “We’re satisfied the plant meets our requirements to restart safely, and we’ll monitor Dominion’s ongoing tests and inspections during startup of both reactors.”

Let’s hope inspectors work holidays.

Advertisements

The Party Line – September 9, 2011: Shaken, But Still Not Stirred

Sunday, September 11, will of course be the tenth anniversary of a tragedy that fundamentally changed America in ways we are still trying to understand. But this 9/11 is also a day for other anniversaries, ones that will likely get little, if any, recognition in the US.

In 1985, for instance, September 11 saw a Keystone Kops-like collection of miscues during a test of the remote shutdown protocols at the Limerick Generating Station, a boiling water nuclear reactor outside of Philadelphia. During the shutdown, a valve on a cooling system failed to open, and attempts to manually open the valve were met by a locked door, and a call for a key, which, after a 15-minute wait, turned out to be the wrong key. Once the proper key was found and the door was opened, the operators found the valve’s hand wheel chained and padlocked to prevent accidental opening. Those keys were in the abandoned control room. Bolt cutters had to be used before the operators could finally open the valve.

All that time, the reactor core’s temperature was increasing. Fortunately, the test was done during startup, when decay heat is relatively low, so control rods were able to slow the reaction enough to provide time to overcome the multiple barriers to opening the valve. Had the plant been operating at full power when this series of problems occurred, the outcome would likely have not been so rosy.

September 11 will also mark six months since the massive earthquake and tsunami that struck northern Japan triggered a series of cataclysmic failures at the Fukushima Daiichi nuclear complex. That accident provides no amusing anecdotes or happy endings, but those horrible events should provide a loud wakeup call and numerous object lessons for nuclear power programs across the globe.

As previously noted, the Japanese nightmare and domestic political realities have spurred German Prime Minister Angela Merkel to announce a rather rapid phase out of her country’s nuclear plants. The Japanese government, too, has spoken of turning away from nuclear power and toward renewable alternatives.

But here in the United States, six months on from Japan’s quake, there are no such proclamations or pledges–if anything, quite the contrary–and almost no movement on even the most incremental of recommendations.

In the face of lessons still not learned, a trio of nuclear experts gathered in Washington, DC on September 8 to highlight key concerns that still have not been addressed six months after the start of the world’s worst nuclear accident. Included on the list are several issues discussed in this space since the Fukushima quake (this is a partial and edited list–please use the link for more concerns and more explanation):

The U.S. regulatory response since Fukushima has been inadequate. “Six months after Fukushima, it seems clear that the U.S. is not going to undertake the type of fundamental, no-holds-barred look at its nuclear regulatory practices that followed the much less serious accident at Three Mile Island some 30 years ago.”

America should avoid post-9/11 mistakes in tightening reactor safety standards. “In responding to Fukushima by issuing orders, the NRC should not make the same mistakes as it did following 9/11, when industry stonewalling delayed implementation of critical security measures for many years. Even today, some post 9/11 security upgrades have not been completed at numerous plants. . . . The U.S. must respond to Fukushima in a much more comprehensive way or it may soon face an accident even worse than Fukushima.”

The U.S. was warned of Fukushima-style problems but failed to act … and is still failing to do so. “U.S. reactors have some of the shortcomings of the Fukushima plants. Furthermore, citizen groups and scientists had tried to call one of these – spent fuel pool vulnerability — to Nuclear Regulatory Commission attention during the last decade. The NRC dismissed these efforts. . . . Without a root cause analysis of its own failure to heed the now validated warnings about spent fuel pools, the NRC may patch the technical problems revealed by Fukushima, but it won’t fix the underlying shortcomings that allow defects to persist until catastrophic events rather than regulatory vigilance force the nuclear industry and the public to face up to them.”

Emergency planning zones in the U.S. must be expanded. “In contrast to the [NRC] Task Force conclusions, we believe that emergency planning zones should be expanded, certain hydrogen control measures should be immediately enforced and spent fuel transfer to dry casks should be accelerated. Also, the safety margins of new reactors need to be reassessed.”

The recent East Coast earthquake should spur more NRC safety analysis. “The earthquake near the North Anna nuclear plant, which reportedly exceeded the plant’s seismic design basis, reinforces the urgency of the NRC Fukushima task force’s recommendation that all plants immediately be reviewed for their vulnerability to seismic and flooding hazards based on the best available information today.”

To that last point, as noted before, the earthquake that struck Mineral, VA in late August should have moved US nuclear regulators to quickly adopt the recommendations of the Fukushima task force. Well, the quake doesn’t seem to have moved the NRC much, but it did move some things, like most of the 117-ton dry storage casks at the North Anna facility. . . and, as we now have learned, pretty much everything else there:

Last month’s record earthquake in the eastern United States may have shaken a Virginia nuclear plant twice as hard as it was designed to withstand, a spokesman for the nuclear safety regulator said on Thursday.

Dominion Resources told the regulator that the ground under the plant exceeded its “design basis” — the first time an operating U.S. plant has experienced such a milestone. . . .

That a facility experienced such a milestone is now known because, over two weeks after the fact, data from the so-called “shake plates” has finally been released (almost a week after it was expected):

“We are currently thinking that at the higher frequencies, the peak acceleration was around 0.26” g, which is a unit of gravity that measures the impact of shaking on buildings, said Scott Burnell, an NRC spokesman.

The plant was designed to withstand 0.12 g of horizontal ground force for parts that sit on rock, and 0.18 g for parts that sit on soil, Burnell said.

Dominion’s sensors recorded average horizontal ground force of 0.13 g in an east-west direction and 0.175 g in a north-south direction, officials said.

The apparent discrepancy seems to stem from the distance between instruments used by the US Geological Survey and those cited by North Anna’s operator, Dominion, but even taking the smaller numbers, the design limits of the plant were exceeded.

Dominion officials have been quick to point out that even though some things have moved and some structures show cracks, those changes are merely cosmetic and in no way dangerous. But nuclear engineer John H. Bickel says that vessels and pipes are not the first things to go in a quake:

[A]n analysis of plants hit by earthquakes had shown that the most vulnerable components were ceramic insulators on high-voltage lines that supply the plants with power and electrical relays, which resemble industrial-strength circuit-breakers and switches.

Even if the relays are not damaged, they might be shaken so that they change positions, cutting off the flow of electricity or allowing it to flow without any command from an operator.

As previously noted (with more than a hint of irony), in order to safely generate electrical power, nuclear plants need an uninterrupted supply of electrical power. Without electricity, cooling systems and important monitors in both the reactors and spent fuel storage pools cannot function. Without effective cooling, nuclear facilities are looking at a series of disasters like the ones encountered at Fukushima Daiichi. That the most quake-vulnerable components directly affect a nuclear plant’s power supply is yet another data point underscoring the urgent need to review and enhance seismic safety at US facilities.

But even before that nation-wide examination can take place, the damage to the shaken North Anna plant needs to be surveyed and analyzed so that Dominion might restart its reactors. What does Dominion need to show in order to get the thumbs up, what criteria need to be met, what repairs or retrofits should be required? To paraphrase the head of the NRC: Who knows?

In an interview last week, NRC Chairman Gregory Jaczko told Reuters it was unclear what the plant would need to show to resume operations because it is the first time an operating plant has sustained a beyond-design-basis quake.

As Hurricane Irene revealed the lack of national guidelines for what to do in the face of an approaching storm, the Virginia earthquake has shown that the United States has no regulatory regime for learning, analyzing, or acting on data from events that exceed the often-negotiated-down design parameters of its nuclear facilities.

In fact, the NRC does not even have a post-quake inspection protocol. Inspections of North Anna are being done according to procedural guidelines drawn up by the Electric Power Research Institute, “a nonprofit utility consortium that has inspected dozens of industrial plants hit by earthquakes around the world.”

Yes, the nuclear industry has written its own post-event checklist, and, in the absence of any other standard, is left alone to use it.

That sort of self-policing leads to some noteworthy analysis, like this from a nuclear industry attorney: “You shake something really hard, and it’s not designed to be shaken that hard — it doesn’t mean that it’s broken.”

But there is something even more disturbing, if that is possible, propagated by the weak regulations and weak-willed regulators. It leaves space for arguments like this one from that same industry lawyer:

The incident helps make the case for new-generation nuclear plants, which have additional safety features. . . . “If you can have a car from 2011 vs. a car from 1978, what are you going to put your toddler in?”

Beyond the fact that no one is actually suggesting the 1978 plants get traded in for newer models (just augmented with them), cars have to compete for consumer dollars in a way that nuclear plants do not. Nuclear plants could not be built, fueled, operated or maintained without massive subsidies, loan guarantees, and infrastructure commitments from the federal government.

Also of note, a 2011 automobile is safer and more efficient than a 1978 model because of government regulation. The auto industry has fought improvements like mandatory airbags, three-point restraints, and CAFE standards, but a strong government imposed those requirements anyway. And your toddler is safer in that car because the Consumer Product Safety Commission reviews the design of child car seats, and laws mandate their use.

Where the comparison does work, however, is that both represent a false choice. Just as a car is not the only way to transport a toddler, nuclear plants are not the only means by which to generate power. And in 2011, there are many more choices, and many safer choices, than there were in 1978.

Which recalls the important contrast between a country such as Germany–which, faced with a restive electorate and lessons to be learned from Japan’s misfortune, has made a commitment to not just trade in nuclear but trade up to renewable alternatives–and the US, where corporate influence and politics as usual have left the government with seemingly few options beyond willful ignorance and calcification.

Even without recognition of the Japan quake’s semi-anniversary, September 11 will probably be a tense day for most Americans, especially those with personal connections to the events of ten years ago. But while remembrance will be hard, it will mostly be so because of an event now relegated to history.

Residents of Japan, still living with an ongoing and ever-evolving threat, cannot so neatly define their anguish. And if there is a message to be found in this coincidental concurrence of dates, it perhaps springs from there. While Americans can debate what could have been done to prevent the attacks of 9/11/2001, it is a debate held in hindsight. For the Japanese dealing with the aftermath of their disaster, hindsight still seems like a luxury to be enjoyed very far in the future.

But, for the United States, a debate about what can be done to prevent a Fukushima-like disaster here is theoretically blessed, both because it is a debate that can be had before the next crisis, and because it is a debate that can be informed by events. And experience, science, economics and common sense are all pretty clear on what needs to be done.

The Party Line – September 2, 2011: Earthquakes, Hurricane Highlight Serious Flaws with Nuclear Power and its Regulation

On Friday, August 26, as Hurricane Irene began its slow journey up the US central Atlantic coast, power companies operating 20 nuclear reactors in nine states made plans to deal with the storm and its potential aftermath.

North Carolina’s Brunswick reactors, operated by Progress Energy, were powered down to 70 percent of peak capacity. At New Jersey’s Oyster Creek, near Barnegat Bay, plant operator Exelon chose to shutdown its reactor completely. Dominion Resources, owner of New London, Connecticut’s Millstone plant took one reactor down to 70 percent, the other to 50 percent.

Dominion’s Surry plant in Virginia stayed at full power, as did Entergy’s Indian Point, 35 miles north of New York City, and the Pilgrim plant in Massachusetts.

The reason some plants chose to reduce output or go offline was because, if an accident caused or required the plant to scram–that is, quickly and completely shut down–the stress on the reactor increases the chance of a future safety breach. As Bob Alvarez, of the Institute for Policy Studies, explains:

Keep in mind that when these large reactors scram, it’s like a jumbo jet making a quick forced landing. The sudden insertion of control rods creates unexpected stress on the reactor. This is why when a reactor is normally shut-down for refueling, it is done gradually. If a reactor experiences several scrams during a year, this should raise a red nuclear safety flag.

While working in DOE, I was involved in energy emergency planning, and electricity blackouts, NRC staff were definitely concerned about the safety of increased scrams caused by forced power outages.

By reducing output, a reactor comes under less stress during a rapid shutdown. It is like hitting the brakes at 35 mph as opposed to slamming them on at 60 mph. The stop is faster and results in less wear-and-tear on the vehicle.

One plant that decided not to reduce output was Constellation Energy Group’s Calvert Cliffs facility near Lusby, Maryland. That was probably a mistake:

A nuclear power reactor automatically went offline late Saturday in Calvert Cliffs after its main transformer was hit by a piece of aluminum siding that Hurricane Irene had peeled off a building. . . .

A follow-up NRC Daily Event Report filed on August 29 by Constellation Energy to the NRC identified that the wind blown debris crashed into an electrical transformer at the Calvert Cliffs nuclear station causing an electrical short and “An unanticipated explosion within the Protected Area resulting in visible damage to permanent structures or equipment.”

To be clear, automatically going offline is a scram.

That is bad news for CEG, which has to keep the reactor offline pending a full inspection by the Nuclear Regulatory Commission, but it might have actually been good news for the surrounding communities. As it turns out, the transformer explosion was not the only problem encountered at Calvert Cliffs during Irene’s visit. As the NRC’s August 29 Daily Event Report [PDF] states:

At 2400, 8/27/2011, numerous alarms on the 1A DG [Diesel Generator] started to be received. These were investigated and it was found that water was intruding down the DG exhaust piping resulting in a DC ground. Based on these indications the 1A DG was declared inoperable and appropriate technical specifications implemented.

In other words, the backup power generator would not have worked if the Calvert Cliffs reactor had lost its main power source. As previously observed, nuclear plants require a steady stream of electric power to operate safely, as cooling systems and monitoring devices depend on it.

It was also noted in the NRC event report that Hurricane Irene “disabled public notification sirens in two counties in the reactor’s emergency planning zone.” They lost power, and CEG had not provided any battery back-up system. So, if an accident severe enough to require precautions or evacuation took place that night, large numbers of people would have been left in the dark, as it were. As the editors of Beyond Nuclear put it, “So much for defense in depth.”

And so much for oversight, it seems. The problems at Calvert Cliffs are not really a revelation–at least not to the NRC:

Calvert Cliffs nuclear power plant in Southern Maryland is due for closer scrutiny by federal regulators after unspecified security lapses discovered there earlier this year.

The Nuclear Regulatory Commission has finalized a “greater than green” finding of security deficiencies spotted during a special inspection from January to July of this year, according to a letter released Wednesday. The agency has not disclosed the nature of the problems, saying that releasing such information might help someone to attack or sabotage the twin-reactor plant in Lusby in Calvert County.

That is the sum total of an item in the August 31 Baltimore Sun. Curious civilians with an abundance of time can access some of the reports through the NRC’s Calvert Cliffs page, but there is no digest for lay readers.

And even the untrained eye might take issue in light of recent developments. For instance, a May report [PDF] on an inspection instigated in the aftermath of Japan’s Fukushima disaster gave a passing grade to backup equipment designed to kick-in if a so-called SBO, or Site Blackout, occurred. As observed, rainfall from Irene rendered a backup diesel generator inoperable.

The lingering safety questions, coupled with dual mishaps caused by high winds and heavy rain, appear not to have resulted in a dangerous event at Calvert Cliffs this time. However, it is just this kind of “what are the chances?” one-two punch that so exacerbated the crisis in Japan, and it is events like this that again should serve as an urgent wakeup call for regulators and legislators alike to quickly implement safety improvements to America’s nuclear facilities.

But step back, and an even larger systemic problem takes shape. Each private energy company made its own decisions on what to do with each of its reactors in the face of an approaching (and somewhat predictable) natural disaster. The call on whether to decrease output or shutdown reactors in advance was not the federal government’s call, not the NRC’s, and not the call of at-risk states or municipalities. There is no federal rule, and, apparently, no federal authority to direct plants on how to operate in cases of multi-region events such as a hurricane.

The NRC’s post-Fukushima-disaster task force did not specifically address this issue, but it did recommend a reexamination of the way the entirety of US nuclear power generation is regulated. The majority of NRC commissioners, however, found even that vague recommendation to be too urgent, and any consideration of this question is now at least 18 months away.

Meanwhile, at North Anna’s quake-damaged plant. . . .

On August 26, Dominion, the company that operates the reactors at Virginia’s North Anna plant, notified the NRC that the 5.8 magnitude Earthquake centered in Mineral, Virginia, might have caused more shaking than the facility was designed to withstand. (Some confusion has surrounded the seismic standard to which North Anna was built. The tolerances are often shorthanded to a Richter scale magnitude number, but, in fact, plant design is supposed to be evaluated against the amount of shaking a quake will cause. Shaking at one point depends on magnitude, but also on the distance from the epicenter and the depth of the quake, as well as other geological factors.) Full results of an examination of the “shake plates” (which measure ground motion) are supposed to be released later today (September 2).

What is already known, though, is that the shaking caused many of North Anna’s dry casks–a type of spent-fuel storage container–to move by as much as four inches. Twenty-five of the 27 vertical casks moved as a result of the quake. Each of those steel and concrete casks contains 32 spent fuel rods and weighs 115 tons. Newer horizontal casks did not move, but some of the 26 (13 already full of spent fuel) show what has been termed “cosmetic damage” to exterior concrete.

As discussed, but, as noted here, not addressed in the NRC task force report, dry cask storage is preferable to the spent fuel pools where “fresher” old fuel is stored at most US plants. Pools require a dependable electrical source to keep liquid circulating and completely covering stored fuel rods. An interruption of power or damage to the cooling system can cause dangerous conditions where the liquid overheats, boils away, and even “cracks” as a result of the nuclear reaction, which accelerates as the pools heat and disappear, and hydrogen explosions are possible, further damaging the vessels and sending radioactive material into the atmosphere.

Dry casks store fuel further removed from “active service,” and are cooled by naturally circulating air.

While the March quake and tsunami provoked the described dangerous events in Fukushima Daiichi’s spent fuel pools, there are no reports of any problems with any of Japan’s dry casks.

But the movement of and damage to North Anna’s casks, though minor, is not meaningless. Beyond the contrasts with liquid storage, the August event highlights the lack of a national repository for spent-but-still-highly-radioactive nuclear fuel. Fifty-five of the nation’s nuclear facilities currently have dry casks on site, but the United States has no centralized facility for the long-term storage. And, since the Obama administration declared Nevada’s partially built Yucca Mountain repository closed, the US has no current plan for the disposal of this dangerous material.

The NRC Fukushima task force acknowledges the need for a long-term plan, but there exist no specific recommendations and no process or funding for developing any.

And speaking of Fukushima. . . .

Al Jazeera has a disturbing report on radioactive waste from the ongoing nuclear disaster overwhelming sewage treatment facilities hundreds of miles from Fukushima.

In Japan, before March, processed sewage sludge was often shipped out for use by fertilizer and concrete manufacturers. But now, even far from the destroyed nuclear plant, the sewage is too dangerous for any use. As a result, piles of highly radioactive sludge are accumulating at sewage plants that have no capacity or expertise for handling the toxic material. Instead, containers and piles of sludge are just being lined up at the processing plants, out in the open, covered by simple plastic tarps. Workers are told they face no imminent danger, but Geiger counters say otherwise.

 

The Japanese government has no plan for dealing with this latest sinister wrinkle, saying only that it is not yet an urgent problem.

Such a lack of urgency is stunning and sad for a country and a people so directly in harm’s way, but a similar lackadaisical, industry-coddling attitude in the US should be no less troubling. True, nothing as terrible as Japan’s catastrophe has yet occurred at an American nuclear plant, but it is not beyond the realm of possibility, as almost every passing week or natural disaster seems to accentuate.

Theoretically, the United States has a body tasked with responding to these new probabilities–the Nuclear Regulatory Commission. And if the NRC won’t do its job, the US has a body with strict oversight powers–Congress. The Congress and the president also have the ability to demand from the nuclear industry improvements in safety and emergency preparedness in exchange for the federal subsidies and loan guarantees the industry needs to operate at all.

But if the Commission or the politicians cannot break free of their cozy relationships with–and the campaign donations from–private energy companies, then who or what, beyond nature, will hold the nuclear industry accountable?

The lifespan of a nuclear plant or a political career is short, but the half-life of many byproducts of nuclear power generation is long. In some cases, very, very long. Is any nation’s political system able to take that long a view?

The Party Line – August 26, 2011: Virginia Quake Yet Another Wakeup Call for Sleepy Nuclear Regulators (Plus: Japan’s PM Resigns)

Late Thursday, Sen. Dianne Feinstein (D-CA) made this observation over at The Huffington Post:

Uninterrupted electricity is essential for nuclear safety. Without electricity, nuclear power plants are unable to pump cooling water through reactor cores and spent fuel pools to prevent overheating and fuel melting.

Without power, plant operators cannot control reactor activity or remotely monitor spent fuel.

It was the loss of electrical power that led to the partial-meltdown of multiple reactors, significant radiation release and damage to the spent fuel pools at the Fukushima Daiichi plant in Japan after the devastating 9.0 earthquake and tsunami in March.

First, I can’t move on without noting two problems there in the last paragraph.

I don’t know how Feinstein defines it, but I think most of the world has dropped the “partial” from the assessment of the meltdowns at Japan’s Fukushima Daiichi nuclear facility. Maybe DiFi has some secret pictures that show tiny bits of intact cladding floating on top of the blobs of corium now understood to be at the bottom of at least some of the damaged reactors, and so she feels uncomfortable going all the way, but the company that nominally runs the facility and the country that is unlucky enough to serve as its home feel sure enough to call it a meltdown without the modifier, so I think US Senators should, too.

Also, it is now believed that a meltdown in at least one of the reactors started before the tsunami that followed Japan’s March 11 earthquake. In other words, as I reported previously, the earthquake damaged the containment vessel or, more likely, the cooling system before the massive wave knocked out the backup generators and, thus, power to the cooling system. So, the loss of power did not lead to at least some of the meltdown—earthquake damage did.

That is not just an academic nitpick, it goes directly to how Feinstein and the entire US regulatory structure should evaluate the safety of domestic nuclear power plants.

Second: “Uninterrupted electricity is essential for nuclear safety.” Just think about that for a second. Uninterrupted electricity is essential for the safe generation of electricity. It is a logic that seems as vulnerable to reason as nuclear cooling systems are to seismic and tidal events.

But third, I do want to congratulate Senator Feinstein for recognizing and writing the obvious:

The incident [Tuesday’s magnitude 5.8 quake centered in Virginia] was a stark reminder of how vulnerable America’s nuclear power plants are to natural disasters.

I mean that congratulations sincerely. Yes, we didn’t really need a new reminder—Japan’s Fukushima disaster is recent and ongoing—but the Mineral, VA earthquake was another indication that our nuclear plants are vulnerable to natural and manmade disasters at many points. And more American politicians should say just what DiFi said, instead of brushing off Japan’s already extant stark reminder as a “can’t happen here” event, or quickly forgetting Tuesday’s quake because it resulted in “minimal damage and no loss of life” (to use Feinstein’s own rosy words).

Feinstein continues by laying out four “lessons” that Japan and Virginia should teach us. (It is really more like two or three points with repeats, but that’s OK.) The headlines:

First, our country needs a comprehensive, national policy to address the management of spent fuel, the radioactive waste produced while generating electricity by fission.

Second, today’s efforts to protect against seismic and flooding hazards may not be sufficient.

Third, we must improve the redundant safety systems to respond to disasters.

Finally, for spent fuel stored at reactor sites, dry casks are safer and more secure than permanent storage in spent fuel pools.

Both the first and fourth points note that storing spent fuel in pools of circulating water is not a particularly safe, efficient, or cost-effective way of dealing with one of nuclear power generation’s biggest problems. Not only are these pools also dependent on an uninterrupted source of electricity to keep water circulating and levels high enough to keep the rods—now packed in at many times the pools’ original designed capacity—from overheating and melting themselves or cracking the water and triggering hydrogen explosions, the cooling systems for the pools are also vulnerable to seismic events.

Feinstein says that spent rods should be moved to dry casks and eventually to a secure repository, observing that spent fuel in Japan housed in dry casks had no problems after the March 11 quake and flood. Strangely, though, the senator cites the Nuclear Regulatory Commission’s special taskforce report on the aftermath of the Japanese disaster as the inspiration for making this call for dry casks and a national fuel repository—strange because, as both Physicians for Social Responsibility and I noted back when the report was released, the task force pointedly did not make any recommendations for moving spent fuel to dry casks or to off-site repositories.

Feinstein also says she has learned that protections against earthquakes and flooding may not be sufficient. Again, DiFi modifies—there is really no need to say “may” here. From Fukushima Daiichi to the reactors in Virginia known as North Anna 1 and 2, it should now be very clear that nuclear plants are walking a precarious line between “minimal damage” and catastrophic failure.

Let’s look more closely at what happened on Tuesday. A 5.8 earthquake centered 15 miles from the North Anna nuclear power generating facility cut electrical power to the plant. Backup diesel generators kicked in to provide power to the cooling systems, averting the overheating of either the reactor core or the pools of spent fuel. Good news, as far as it goes, but there are several disconcerting caveats.

First, we don’t know if the plant—which is theoretically designed to withstand a quake of a 6.2 magnitude—has actually emerged from Tuesday’s tremor completely unscathed. The reactors are currently being brought to a cold shutdown so that they may be inspected further. Not only must the containment vessels be more closely inspected, the cooling system must be tested for leaks. Some of the pipes and conduits for that system are underground. As reactor expert Paul Gunter has noted, an underground rupture, one that might be leaking radioactive tritium into ground water, is quite possible and needs to be investigated more fully.

(As a caveat to the caveat, I must note that we also need to find a way to verify that the public is being fully informed about any damage and radioactive leaks—not a sure thing in light of both the evolving story of cover-up in Japan and this summer’s expose on collusion between the NRC and the nuclear industry.)

Second, the North Anna plant gets its name from Lake Anna, an artificial lake created to provide a reservoir for the cooling requirements of the nuclear facility. What if the quake had caused the dam that holds the water in Lake Anna to rupture? Beyond the dangerous flooding to well-populated communities downstream, the water level in the reservoir would drop to a point where the nuclear plant’s cooling system would fail. If this were to happen, no amount of redundant power generation would fix the problem. Does this sound farfetched? It is not. Virginia is noteworthy for its lack of attention to its aging infrastructure—in fact, according to the American Society of Civil Engineers’ infrastructure report card [PDF], the condition of Virginia’s dams gets a D-minus.

(It should be noted that the initial inspection of the Lake Anna dam after Tuesday’s quake showed no new damage.)

Third, not all of North Anna’s backup generators worked on Tuesday. Only three of the four came online after power was lost. (Hooray for required redundancy.) What is not clear is what effect this had on the plant’s ability to function normally, or what would have happened if grid power had not been restored as quickly to the facility.

Fourth, there is emerging evidence that seismic activity can increase as the result of the pressure from dammed reservoirs, as well as from hydraulic fracturing (which has been going on in the vicinity of Tuesday’s epicenter).

And finally, to simply give a Richter scale number as a sort of assurance of the safety of a nuclear facility is overly simplistic if not downright deceptive. Here’s why:

As noted here today and before, there are many systems that have to survive an earthquake—the reactor containment vessel, its cooling system, the spent fuel pools, their cooling systems, the reactor building, the monitoring equipment, and a plant’s connection to a steady supply of electrical power. In theory, all these systems were evaluated when the plans for a nuclear facility were initially approved. They all should survive a quake of a specified magnitude.

However, all of America’s nuclear facilities were licensed during a time when regulators assessed designs based on what is called Deterministic Seismic Hazard Analysis (DSHA). But, as noted in a May Congressional Research Service report [PDF]:

Since then, Probabilistic Seismic Hazard Analysis (PSHA) has been adopted as a more comprehensive approach in engineering practice. Consequently, the NRC is reassessing the probability of seismic core damage at existing plants.

I am not an expert in plate tectonics, but what I read tells me that you would feel more secure with a PSHA-generated standard—and what I have learned from Fukushima is that I want that standard applied to all the systems needed to safely operate a nuclear power plant. But what this report tells me is that the NRC is only in the midst of some process of reevaluating plants’ seismic vulnerability—a process that was to have begun last year but has moved very slowly (and this is only the evaluation stage)—and that this re-evaluation is of the probability of core damage, which, to my eye, is not the same as an evaluation of every system needed for the reactor and the spent fuel pools to remain safe.

And I am not alone in my worries. Here’s the NRC itself after it looked at North Anna in April (via the Institute for Southern Studies and the Center for Public Integrity):

Specifically, the NRC report notes that portions of water and gaseous suppression systems and hose stations “are not seismically designed.”

The report noted that “potential leakage can occur through penetrations following seismic event.”

And with specific regard to the spent fuel pools, ISS continues:

There’s also concern about what a major quake would mean for the water-filled pools used to store spent fuel at most U.S. nuclear plants. Bob Alvarez, a senior scholar at the Institute for Policy Studies who recently authored a report on the dangers of spent fuel storage in the United States, addressed the issue in a piece on the IPS blog posted shortly after the quake:

The North Anna reactors are of the Westinghouse Pressurized Water design and went on line in 1979 and 1980 respectively. Since then the reactors have generated approximately 1,200 metric tons of nuclear spent fuel containing about 228,000 curies of highly radioactive materials — among the largest concentrations of radioactivity in the United States.

Alvarez went on to note that almost 40 percent of the radioactivity in North Anna’s spent fuel pools is in the form of cesium-137, a long-lived isotope that presents serious health risks and accumulates in the food chain. He continued:

The spent fuel pools at North Anna contain four to five times more spent fuel than their original designs intended. As in Japan, all U.S. nuclear power plant spent fuel pools do not have steel lined, concrete barriers that cover reactor vessels to prevent the escape of radioactivity. They are not required to have back-up generators to keep used fuel rods cool, if offsite power is lost. Even though they contain these very large amounts of radioactivity, spent reactor fuel pools in the United States are mostly contained in ordinary industrial structures designed to protect them against the elements.

This goes to explaining the confusion I see over whether just parts or the entirety of a nuclear facility is required to meet a specific earthquake safety standard. But what it doesn’t do is imply that a single, plant-wide standard will be used in the future.

As noted when the special task force report came out earlier this summer, the recommendation that the current patchwork of safety rules should be unified and standardized was actually being slow-walked by three of the five NRC commissioners. Finally, one week ago, the commission agreed to give its technical team 45 days to analyze some of the recommendations, but they will be given a full 18 months to analyze the recommendation that the NRC revise its entire regulatory framework in light of lessons learned after the Fukushima disaster.

It should also be noted that there is currently no law that requires the NRC to apply the new, better seismic standards when evaluating requests for license renewals or the building of additional reactors at existing facilities. (There is a bill, languishing in the House, designed to fix this. . . did I mention it was languishing?)

Which brings us back to Senator Feinstein, or, really, her California colleague, Sen. Barbara Boxer (D), who chairs the Committee on Environment and Public Works and has oversight responsibilities over the NRC. While DiFi has written about the lessons of this week’s Virginia quake, Boxer has demanded action on the NRC taskforce report on the lessons learned from Fukushima. At a hearing on August 2, Boxer demanded the NRC pick up the pace on evaluating the recommendations and report back to her by November. With the NRC’s decision on how it will move forward, and the latest in a lengthening string of “wakeup calls” having caused incidents at North Anna and a number of other eastern nuclear facilities, perhaps both of California’s Senators might consider official hearings before then.

It must also be mentioned that while I was writing this post, Japan’s Prime Minister, Naoto Kan, has stepped down. Stories on the resignation concurrently cite his dismal poll numbers from an anti-nuke electorate, and the lack of support from pro-nuclear members of his party. Kan, who had previously hinted at leaving after the Fukushima crisis was brought under control (it seems I correctly predicted he’d be gone well before that), has also signaled that he wanted to wean Japan off nuclear power for electrical generation and move more aggressively toward renewable sources. Both possible reasons for his early exit speak to some form of accountability—one to the public, the other to entrenched nuclear industry masters—and both have probably played some roll. But what matters going forward is to whom the next leader will answer, and what happens with Japanese nuclear facilities will make that very clear.

In the US, we have a less clear choice—no one has proposed a move away from nuclear power (quite the contrary)—which, alas, probably tells us who calls the shots in our country. But that ugly political reality doesn’t change the physical one—United States nuclear facilities remain vulnerable to numerous seismic and tidal threats. As Diane Feinstein concludes, “We need to learn the lessons we can to assure that next time we are ready—not just lucky.”