Virginia US Earthquake - Nuclear Plant

Click For Summary
SUMMARY

The recent earthquake in Virginia, initially reported as a magnitude 5.9, was centered near the North Anna Nuclear Generating Station in Mineral, VA. The quake caused reactor trips and a loss of offsite power, prompting the plant to declare an alert status. Despite the seismic event, the plant's safety systems functioned, with emergency diesel generators activated and steam venting occurring as a normal safety procedure. The North Anna facility is designed to withstand seismic events up to a magnitude of 5.9, ensuring that critical safety components remain unaffected.

PREREQUISITES
  • Understanding of seismic safety protocols in nuclear power plants
  • Familiarity with the North Anna Nuclear Generating Station's operational parameters
  • Knowledge of emergency power systems in nuclear facilities
  • Awareness of steam generation and venting processes in nuclear reactors
NEXT STEPS
  • Research the seismic design criteria for nuclear power plants, focusing on the North Anna facility
  • Explore the role of emergency diesel generators in maintaining safety during power outages
  • Learn about the steam venting process and its implications for reactor safety during shutdowns
  • Investigate the regulatory framework governing nuclear plant emergency protocols
USEFUL FOR

Nuclear engineers, safety analysts, emergency management professionals, and anyone involved in the operation or oversight of nuclear power facilities will benefit from this discussion.

  • #31


zapperzero said:
http://www.usatoday.com/tech/scienc...lts-were-double-nuke-plants-design/50304434/1

Every design spec concerning shock that I've seen includes duration; none are given in the article. For instance, humans can tolerate hundreds of g's for a micro or millisecond duration; but 10-15 g's over tens of seconds can cause loss of consciousness or be fatal.
 
Engineering news on Phys.org
  • #33


nteresting meeting.

Dominion results show that the single values of 0.06g OBE and 0.12g DBE were exceeded at points along the frequency spectrum of the earthquake. Further their CAV limit was also exceeded (I'm goiung to need to look that up).

Based on the nature and number of questions raised by NRC staff, Dominion is going to be hard pressed to get Unit 1 up and running in the immediate future. NRC still has no idea what form of submittal or documentation they will require from ominion as a prerequisite to restart.

Basically Dominion made a case for restart after they complete inspections and surveilance tests based on the following points:

  1. The earthquake was of short duration and the total energy was low compared to what would be seen from a full OBE or DBE earthquake spectrum
  2. The actual event spectrum was at a level where they believe that simple non-commercial structures would have a safety margin factor of 3 before damage to stuctures would be expected.
  3. Industrial buildings and seismically qualified systems structures and components would have even greater margins. Therefor, they would expect no damage.
  4. Their inspections and tests have not detected any functional damage in non-safety or safety systems.
  5. They have seen no damage in non-safety equipment which would be considered at the lowest levels of standards such as building codes that cover domestic plumbing and waste systems. Dominion believes this gives credence to believe there is no hidden damage in safety systems.
  6. Unit 2 is off line for refueling now and will undergo a complete set of physical and surveilance tests for 100% of the systems and a complete civil engineering assesment of the structures. They believe this will allow restart of Unit 1 pending the same level of testing in 2012 during the next refueling outage.

Dominion managemment and NRC management at the table were talking in terms of restarting unit 1 in a matter of weeks or a few months. The staff that asked questions sounded like they were gearing up for a review that could take much longer. The KK plant in Japan actually had visible damage from an earthquake and was off line for years. Several of the NRC technical staff came to the microphone giving out there wishlists for information that sounded like licensing a new plant. North Anna may be held ransom to resolve the GSI-199 issue and the Fukushima lessons learned.

Only one member of the public spoke - Paul Gunther for those who know the intervenors out there. He raised the issue of buried piping.


Did anyone else listen in? What was your take?
 
  • #34


NUCENG said:
...North Anna may be held ransom to resolve the GSI-199 issue and the Fukushima lessons learned...
I can't see how this NRC action can resolve either beyond the specific case of Dominion's North Anna. US new plant construction is dead, and I can't imagine any major NRC action against the existing 104 US plants.
 
  • #35


I listened for a while although I didn't get many of the jargon (what is level 4 / level 6 status?)
It really sounded to me like there is no damage that would prevent it to go online... one of the important things they proved is that the fuel is undamaged using the chemistry of primary coolant.

There were some issues that were probably not handled very confidently, like they kept on stating that because the non-security related piping was checked and found problem-free then the security related piping was assumed to be problem-free. In an ideal world it makes sense but how about the stress that was in the pipes while earthquake hit?

I also noticed that NRC stated they don't (yet) have a set of requirements for approving online status after a beyond-design-basis event and one of the NRC guys said that the proposed timeline for restarting No1 is too short for them to come up with the proof that No1 can be restarted safely which sounded right to me.

Oh and one more thing - the diesel generator was manually shut down after a coolant leak from a gasket and they felt it's better to shut it down. It is assumed that a torquing technique was misused for that gasket and the other generators didn't exhibit the issue.

Apologies for any mistakes, I was multitasking...
 
  • #36


mheslep said:
I can't see how this NRC action can resolve either beyond the specific case of Dominion's North Anna. US new plant construction is dead, and I can't imagine any major NRC action against the existing 104 US plants.

It happens all the time. NRC is a large group of very smart and educated scientists and engineers. If a staff reviewer has a pet project it can be very difficult to keep them from making a mountain out of a molehill (or in government bureaucracy - an atom into a galaxy). They are very effectively protected by the NRC Differing Professional Opinion process. It goes along with another abusive tactic of "Regulating by Inspection." It is not uncommon for one plant to be forced into taking drastic actions to get a license amendment approved or a restart permission as in the case of North Anna. Once one plant is forced to submit to this blackmail it tends to be easier to force others to fall in step because the "precedent" has been set.

This may sound like sour grapes, but abusive regulation can actually divert attention and resources from other priorities. NRC has not yet concluded the processing of GSI-199 and there is a lot of the cause and lessons from Fukushima that we don't know. I will say for the record that seismic qualification issues needs to be at the top of the priority list, but that may not be good news for North Anna.
 
  • #37


shadowncs said:
I listened for a while although I didn't get many of the jargon (what is level 4 / level 6 status?)
It really sounded to me like there is no damage that would prevent it to go online... one of the important things they proved is that the fuel is undamaged using the chemistry of primary coolant.

There were some issues that were probably not handled very confidently, like they kept on stating that because the non-security related piping was checked and found problem-free then the security related piping was assumed to be problem-free. In an ideal world it makes sense but how about the stress that was in the pipes while earthquake hit?

I also noticed that NRC stated they don't (yet) have a set of requirements for approving online status after a beyond-design-basis event and one of the NRC guys said that the proposed timeline for restarting No1 is too short for them to come up with the proof that No1 can be restarted safely which sounded right to me.

Oh and one more thing - the diesel generator was manually shut down after a coolant leak from a gasket and they felt it's better to shut it down. It is assumed that a torquing technique was misused for that gasket and the other generators didn't exhibit the issue.

Apologies for any mistakes, I was multitasking...

Nope, those are good points. I didn't hear "level4/level6", probably because it made sense in context, do you remember anything about what they were discussing?
 
  • #38


NUCENG said:
Nope, those are good points. I didn't hear "level4/level6", probably because it made sense in context, do you remember anything about what they were discussing?

I've seen them on a slide, I think unit 2 would be in leve 6 (can't remember when) and unit 1 in level 4 meaning ready to restart.
 
  • #39


NUCENG said:
It happens all the time. NRC is a large group of very smart and educated scientists and engineers. If a staff reviewer has a pet project it can be very difficult to keep them from making a mountain out of a molehill (or in government bureaucracy - an atom into a galaxy). They are very effectively protected by the NRC Differing Professional Opinion process. It goes along with another abusive tactic of "Regulating by Inspection." It is not uncommon for one plant to be forced into taking drastic actions to get a license amendment approved or a restart permission as in the case of North Anna. Once one plant is forced to submit to this blackmail it tends to be easier to force others to fall in step because the "precedent" has been set. ...
Oh? Can you name such an instance? I'm not referring to NRC policy updates are universally mandated all the time but have little cost relative the plant itself. This time we are talking about major seismic upgrades of plants and/or spent fuel storage. Universal implantation of such a policy will force some of the marginal operators to simply close. Since 3-Mile Island, when has there been a similar case?
 
  • #40


NUCENG said:
It happens all the time. NRC is a large group of very smart and educated scientists and engineers. If a staff reviewer has a pet project it can be very difficult to keep them from making a mountain out of a molehill (or in government bureaucracy - an atom into a galaxy).
Or making a career out of an issue. :rolleyes:
 
  • #41


shadowncs said:
I've seen them on a slide, I think unit 2 would be in leve 6 (can't remember when) and unit 1 in level 4 meaning ready to restart.

OK, now I remember.

They initially kept Unit 1 in hot standby to keep steam driven safety systems available and the steam generators as a cooling path took Unit 2 to cold shutdown. If I recall they took Unit 2 down further because they had to shut down one of the two diesels. They also needed to enter the Unit 2 containment to retrieve the seismic scratch plates. Later when they discovered they had exceeded design basis peak ground acceleration they were required to take Unit 1 to cold shutdown as well.
 
  • #42


mheslep said:
Oh? Can you name such an instance? I'm not referring to NRC policy updates are universally mandated all the time but have little cost relative the plant itself. This time we are talking about major seismic upgrades of plants and/or spent fuel storage. Universal implantation of such a policy will force some of the marginal operators to simply close. Since 3-Mile Island, when has there been a similar case?

Okay, Millstone spent millions of dollars doing a complete reconstitution of instrument setpoints beyond anything eventually appklied to the rest of the licensees because they were under a confirmatory action letter. The entire control room habitability issue a few years ago cost the industry millions of dollars for an issue that was demonstrably of such low risk that it was ridiculous. NRC is holding up license amendments for BWR plants due to concerns over an issue known as "containment overpressure" that they have granted to other plants previously. And now North Anna may have stepped up to take one for the team. I could probably come up with more examples. It is inevitable when there is a difference of opinion whether the safety improvement is really necessay or justified.

Don't misunderstand me, in each of these cases the industry was asked to perform analysis, conduct tests, or modify the plant in a way that was more conservative than previous requirements. But nuclear plants are not research institutes. They are businesses and have customers who need energy at affordable prices and shareholders that deserve a fair return on investment. There is some truth in the old story that an elephant is a mouse that was designed to the Code of Federal Regulations.

These are not anywhere near the kinds of issues like Fukushima ignoring tsunami data or Davis Besse ignoring the boric acid caked on the RPV head or Maine Yankee modify a safety analysis code to get the results they wanted. Those are clear safety issues that must be remedied and also involve non-compliance with existing regulations and maybe even criminal laws. I am talking about arguments that come down to a question of "better" vs "good enough."

And remember, I repeat - seismic qualification is a legitimate high priority. North Anna is in the sights at a time when we don't yet know what needs to be done.
 
Last edited:
  • #43


""Oh? Can you name such an instance? ""

Long ago in a galaxy far away,,
some aggressive NRC staffer got a pet project called "Pressurized Thermal Shock".
He asserted that if a pressurizer were ever allowed to compeltely fill it would fracture from the sudden insurge of cold water.
Soo,,, Three Mile Island's operators were directed to never let their pressurizer fill.
Soo,,, that fateful morning when the pressurizer started to fill
the operator obediently shut off the pump.

The Three Mile Island accident lies squarely on the shoulders of that NRC staffer.

Is that why you asked
"Since 3-Mile Island, when has there been a similar case?"



old jim
 
Last edited:
  • #44


The case I'm looking for is one where the NRC has mandated that all US reactors make an in place plant change costing on the order of hundreds of millions of dollars or more, which a seismic withstand upgrade, or a fuel storage upgrade is likely to require.
 
  • #45


mheslep said:
The case I'm looking for is one where the NRC has mandated that all US reactors make an in place plant change costing on the order of hundreds of millions of dollars or more, which a seismic withstand upgrade, or a fuel storage upgrade is likely to require.

Post 9/11 security, estimates are $2 BILLION.
 
  • #46


NUCENG said:
Post 9/11 security, estimates are $2 BILLION.

[offtopic]Peanuts. 4 (count'em, four) B-2 bombers. Also, why would a national security problem get solved with the money of private companies, isn't that what the military is for?[/offtopic]
 
  • #47


zapperzero said:
[offtopic]Peanuts. 4 (count'em, four) B-2 bombers. Also, why would a national security problem get solved with the money of private companies, isn't that what the military is for?[/offtopic]

Most of us have been asking that for over ten years.

A couple of thoughts come to mind.

If you have flown recently and seen TSA in action would you want that group in charge of security, We'd be very well protected if terrorists used grandmothers, nuns, and children for the attack.

There is some evidence that the anti-nuclear lobby believes if they can make nuclear energy more expensive they can get rid of it. Unfortunately it simply increases power costs to customers.

Beyond some point iy is a waste, because the security is already going to make the chance of success unappealing for the terrorists. There are many easier softer targets out there.
 
  • #48


NUCENG said:
Most of us have been asking that for over ten years.

A couple of thoughts come to mind.

If you have flown recently and seen TSA in action would you want that group in charge of security, We'd be very well protected if terrorists used grandmothers, nuns, and children for the attack.

There is some evidence that the anti-nuclear lobby believes if they can make nuclear energy more expensive they can get rid of it. Unfortunately it simply increases power costs to customers.

Beyond some point iy is a waste, because the security is already going to make the chance of success unappealing for the terrorists. There are many easier softer targets out there.

I do not live in the US. This has advantages and disadvantages, in that I am never subjected to the gropings of the erstwhile unemployable (most of Europe actually has professionals working airport security), but I WAS herded without comment or recourse to the new X-ray machine on Schipol. Whenever I pass through airports these days, I think of Domodedovo and nothing else. I am actually less scared of flying commercial than pre-9/11, but more scared of the embarkation line, the security check line, the ticketing line, the taxi line. Sitting ducks.

I hope the TSA is not running the NPP security show, I really do.

Re anti-nuclear activists: those that I know of, at least, do believe exactly that. It's not a bright tactic, but it has potential to work great in the long term, unlike most other accessible ones. Some of these guys eat breathe and sleep leftist/anarchist revolutionary warfare. To them all war is economic war. The rising cost of energy actually plays into their hand. Dissent rises, revolution becomes possible. In the meantime, less people are born and more die because of the higher cost of everything.

Re: the point beyond which security is a waste. Unknown, unknowable. We can make fancy guesses wrt economic efficiency of an attack, speculate on likely threats, but it's all smoke and mirrors. Nuts come in a million flavors.
 
  • #49


NUCENG said:
Post 9/11 security, estimates are $2 BILLION.
$19M/plant. That's far less the seismic hardening might cost.
 
  • #50


mheslep said:
$19M/plant. That's far less the seismic hardening might cost.

And your point is?

Has this sort of expenditure been applied to other industries? Has parking been moved back from sports stadii by 100 yards? Are bridges and tunnels being fortifird? Does the security force at chemical plants outnumber their operating staff?

The point is that nuclear plants are frequently subjected to costly modifications and that is what you asked for examples. The industry has done what was required and still produces competitive power. My point is simply that NRC has never been afraid to regulate, unlike, Japan, apparently.
 
  • #51


NUCENG said:
And your point is?

Has this sort of expenditure been applied to other industries? Has parking been moved back from sports stadii by 100 yards? Are bridges and tunnels being fortifird? Does the security force at chemical plants outnumber their operating staff?

The point is that nuclear plants are frequently subjected to costly modifications and that is what you asked for examples. ...
No, I made my point clear above in 44; cost imposed on NPs and not other industries was not it; small costs were not it.
https://www.physicsforums.com/showpost.php?p=3493268&postcount=44
 
  • #52


mheslep said:
The case I'm looking for is one where the NRC has mandated that all US reactors make an in place plant change costing on the order of hundreds of millions of dollars or more, which a seismic withstand upgrade, or a fuel storage upgrade is likely to require.

Look up GSI-191. NRC study claimed that insulation in the containment would clog sump strainers in event of a LBLOCA. Subsequently most plants had to redesign their containment and construct new sump strainers. It was a multi-year project costing tens of millions per reactor.
 
  • #53


mheslep said:
No, I made my point clear above in 44; cost imposed on NPs and not other industries was not it; small costs were not it.
https://www.physicsforums.com/showpost.php?p=3493268&postcount=44

No, you established a threshold value of "hundreds of millions" I have given you several examples of large expenditures mandated by NRC, some justified, others overblown, and at least one totally unjustified. Every one who has worked in the nuclear industry can probably add to tahat list. If you add these post-construction and post licensing up your threshold has probably been exceeded for individual plants.

So what was your point? You claim that "hundreds of millions" iwill be needed to comply with seismic upgrades. That is probably about 10% or more of the value of an operating nuclear plant. I agree if that is what it takes some plants nearing end of life which haven't received lcense renewals would probably end up being shutdown. There just would be no way to amortize that cost over the remaining life withould pricing themselves out of business.

My take is that if any plant requires that level of expense to comply with justifiable seismic standards, then they already should be shutdown under existing standards. North Anna proved that the existing standards actually may need to be clarified, but actually were still less than the design margins of the plant.

NRC was already working through a Generic Issue (199) process for seismic qualification upgrades prior to the Mineral Virginia earthquake. The result will be new standards for evaluating earthquake risk and ground motion spectra for design analysis. The safety/risk assessment is here:

http://pbadupws.nrc.gov/docs/ML1002/ML100270582.html

The conclusion was that existing plants are have no significant risk but some minor increases in risk goals. I interpret that to mean that most plants will be able to demonstrate adequate margin in existing structures systems and components. This leads me to conclude that your threshold of "hundreds of millions of dollars" is unfounded. North Anna does not bring that conclusion into doubt.

Does this help your concern. Would you like to reconsider the threshold you have set?
 
Last edited by a moderator:
  • #54


NUCENG said:
No, you established a threshold value of "hundreds of millions"
Per plant, as in what North Anna may face for seismic hardening.
 
  • #55


mheslep said:
Per plant, as in what North Anna may face for seismic hardening.

And based on the fact that North Anna did not experience significant damage in the earthquake, what is the basis for your WAG that even they will have to expend "hundreds of millions?" Your threshold is so far beyond reality that it is difficult to believe you are trying to discuss realistic consequences from the earthquake.
 
  • #56


NUCENG said:
And based on the fact that North Anna did not experience significant damage in the earthquake, what is the basis for your WAG that even they will have to expend "hundreds of millions?" Your threshold is so far beyond reality that it is difficult to believe you are trying to discuss realistic consequences from the earthquake.
? I agree, from reports so far, that N. Anna had no significant damage. I'm reacting to your earlier post that none the less the NRC is holding N. Anna for "ransom" to "resolve" the seismic issue.
 
  • #57


mheslep said:
? I agree, from reports so far, that N. Anna had no significant damage. I'm reacting to your earlier post that none the less the NRC is holding N. Anna for "ransom" to "resolve" the seismic issue.

Maybe I misunderstood your point then. I said there was a potential for NRC to hold North Anna hostage based on previous experience. I have no idea how that morphed into "hundreds of millions."

I was explaining that in the past NRC has held a licensee hostage to apply leverage to the industry. That may be a useful tactic, but it can be pretty expensive for the hostage and can rise to regulatory abuse. (Cost of replacement power can be much greater than the cost of resolving the issue depending on how long the issue is unresolved. NRC has not issued their final regulatory analysis on GI-199 so if the hold North Anna's two units in shutdown until the issue is resolved it becomes completely unfair to North Anna, and potentially, any other plant that needs a license amendment or restart permission in the meantime. I say unfair, because first. the NRC is already on record saying that GI-199 does not rise to the level where they could order plants to shutdown to resolve the issue, and second, North Anna design worked during the earthquake.

The politics of restarting North Anna may become more deterministic that the engineering and safety issue. What I heard in the public meeting sounded like a bunch of staffers setting up to do exactly that. North Anna needs to complete their inspections and surveillances and issue the root cause report. NRC needs to issue guidance on what documentation from North Anna for restart. Then NRC needs to prevent piling on issues not related to the earthquake, including final resolution of GI-199 and the Fukushima Task Force recommendations. Those side issues should not be used to delay restart.

Unfortunately, "should" and "shall" are not the same. NRC management at the public meeting weakly agreed that revision of design basis seismic design spectra for North Anna was not a prerequisite for restart. We'll see.

Again, if I misunderstood your point, hopefully we are closer to mutual understanding each other now, even if not in agreement
 
  • #58


NUCENG said:
The industry still produces competitive power.

Not in the UK it doesn't. 2010 taxpayers subsidy amounted to £3 billion for the nuclear power providers ,and that's without any provision for waste management/storage.
How does this compare with other states?
 
  • #59


Caniche said:
Not in the UK it doesn't. 2010 taxpayers subsidy amounted to £3 billion for the nuclear power providers ,and that's without any provision for waste management/storage.
How does this compare with other states?

So that's £48 per capita?
 

Similar threads

Fukushima Japan Earthquake: nuclear plants Fukushima part 2
  • · Replies 2K ·
60
Replies
2K
Views
456K
Mag 2.7 earthquake in Cornwall, 19 Nov 2023
  • · Replies 1 ·
Replies
1
Views
3K
Adirondack Mountains and earthquakes
  • · Replies 2 ·
Replies
2
Views
3K
2004 Indian Ocean earthquake and tsunami (19 years ago)
  • · Replies 2 ·
Replies
2
Views
4K
Low magnitude earthquakes in Scotland, Highlands and Inner Hebrides
  • · Replies 3 ·
Replies
3
Views
4K
Japan Earthquake: Nuclear Plants at Fukushima Daiichi
  • · Replies 14K ·
473
Replies
14K
Views
4M
Fukushima Are US Nuclear Power Plants Prepared for Earthquakes?
  • · Replies 5 ·
Replies
5
Views
6K
What if a nuclear power plant loses outside electricity?
  • · Replies 6 ·
Replies
6
Views
20K
Nuclear fusion power plants - why is it taking so long to make them?
  • · Replies 25 ·
Replies
25
Views
6K
Volanic Ash and Nuclear Power Plants
  • · Replies 12 ·
Replies
12
Views
3K