#### nikkkom

Actually none of this would be possible. Nuclear power plants have higher security than most military bases.
Color me skeptical.

I recall a case where protesters, one of them a nun, managed to come to a nuclear weapons plant's wall and bang on it with hammers for half an hour, and only after that they were arrested. Googgling...

https://www.theguardian.com/world/2014/feb/19/nun-jailed-break-in-nuclear-plant

Aw, I'm wrong. Not half an hour. "They were able to spend more than two hours inside the restricted area before they were caught".

#### nikkkom

Even if they get past security, which is highly improbable.
"Highly improbable"?

Let's think about this for a bit from a perspective of "If I would want to blow up the plant, and have $1B to finance it?". How would one do it? Can this be done? How much would it cost to hire or train 30-something squad of terrorists? To arm them with plenty of automatic weapons, sniper rifles, RPGs, breaching charges? Maybe even add a mortar team and a chopper with a machine gun. I bet a lot less that one billion dollars. You seriously think plant security is ready to face a real military assault team? After spending a decade doing only drills, not any real combat? And if the attackers do defeat the defending security forces, blowing up a hole in concrete is almost trivial in comparison, especially that they know beforehand that they would need to do that - the physical parameters of nuclear plants are hardly a secret. #### mheslep Gold Member basic requirements in the GDCs will still apply: 1) preclude fission products from the environment, 2) maintain controllability of the reactor (nuclear process), 3) maintain coolability of the system. Surely 1 and 2, but why 3? The emphasis on cooling is intrinsic to light water moderated, solid fuel, water cooled reactors, and not molten salt reactors. The solution to overheating in the ORNL MSR experiment was a freeze plug and a dump tank, not multiple levels of redundancy to maintain cooling. Melt downs are not relevant. Steam explosions are not relevant to the nuclear island. Edit: ...In addition, if there was a breach in the primary system, e.g., a leak in the reactor vessel or piping, then one would have to be concerned about leaks of gaseous and volatile fission products, as well as interactions of fluoride or chloride salts with materials. The gaseous and volatile fission products are removed by sparging as they are produced. I expect they are chemically formed into liquids or solids and not stored under pressure. . Even though the primary systems operates a relatively low pressure, there is still need of some containment outside of the reactor vessel, since the primary system will be radioactive. Yes, secondary containment may be necessary, but it does not need to be a structure that can withstand a flash steam explosion from 160 bar primary water. Below is a notional graphic for another MSR design from Thorcon, 557 MWth unit. The 'POT' is primary containment for the nuclear salt. Red piping is 704C salt. The blue PHX exchanges heat to a secondary salt loop leaving in green. The outer red 'silo' is secondary containment, which is turn 14 meters subsurface at its top. The technical description as submitted to IAEA is here: https://aris.iaea.org/PDF/ARISThorCon9.pdf MSR's are not the only design with inherent thermal safety. The EBR-II famously ran a cooling loop shutdown test. Start at 2mins: #### Attachments • 136.8 KB Views: 204 Last edited: #### mheslep Gold Member You seriously think plant security is ready to face a real military assault team? They don't operate forever alone. Plant security need only get the word out and delay the threat for some minutes. "If I would want to blow up the plant, and have$1B to finance it?".
1. Whoever put up $1B to physically attack the country containing the plant has just declared war on that country. 2. The attackers are seriously mentally impaired if they believe they can do the worst damage to the country with their$1B by shooting up a nuclear plant.

#### mheslep

Gold Member
Another molten salt reactor company has fairly detailed video description out. Moltex, out of the UK.

Design highlights:
• Fast reactor, no moderator
• Separate fuel and cooling salts, where the fuel salt is still contained in fuel rod or cylinder. Moltex contends the IAEA will never countenance the molten fuel 'tank' and fuel salt = cooling salt designs proposed by others due to problems in tracking nuclear fuel inventories.
• Fission product nobel gasses are allowed to separate from the fuel enabling improved neutronics, but are still contained in the fuel rod and thus in the core and so need not be managed.
• Operating temperature similar to that of existing gas power turbines, so that common gas turbines can be used which are six times cheaper than nuclear plant turbines.

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#### Astronuc

Staff Emeritus
40+ years ago - what the government thought about nuclear energy and the overall energy outlook in the US.

National Plan for Energy Research, Development and Demonstration (RD&D)

Other documents of interest.
https://www.energy.gov/sites/prod/files/ERDA History.pdf

https://energy.gov/sites/prod/files/FEA History.pdf

https://inis.iaea.org/search/search.aspx?orig_q=RN:11562226

Comparative Analysis of the 1976 ERDA Plan and Program
https://www.princeton.edu/~ota/disk3/1976/7616.html
Chapter 3. Nuclear Issues - see pages 83-84 for MSBR

Staff Emeritus

#### anorlunda

Mentor
Gold Member
Of interest is - NUREG-1226, Development and Utilization of the NRC Policy Statement on the Regulation of Advanced Nuclear Power Plants - particularly Commissioner Asselstine's comments at the end.
Help me. I followed the links you provided, plus the one below, but I can't find those remarks. Perhaps you could quote them here.
https://www.nrc.gov/docs/ML1325/ML13253A431.pdf

#### Astronuc

Staff Emeritus
Help me. I followed the links you provided, plus the one below, but I can't find those remarks. Perhaps you could quote them here.
https://www.nrc.gov/docs/ML1325/ML13253A431.pdf
Yes. Starting on page 64/76, Dissenting Views of Commissioner Asselstine

Asselstine later gave testimony to the House Committee on Science and Technology regarding
Opportunities and Challenges for Nuclear Power
https://science.house.gov/sites/republicans.science.house.gov/files/documents/hearings/042308_asselstine.pdf

#### mheslep

Gold Member
Yes. Starting on page 64/76, Dissenting Views of Commissioner Asselstine

Asselstine later gave testimony to the House Committee on Science and Technology regarding
Opportunities and Challenges for Nuclear Power
https://science.house.gov/sites/republicans.science.house.gov/files/documents/hearings/042308_asselstine.pdf
Asseltine comment in the dissent:
Nor is there guidance on what standards the balance of plant must meet.
What possible reasoning leads NRC commissioners to believe they should be the body that sets standards for non-nuclear balance of plant? IRC, nuclear BoP is far higher than seen at other thermal plants. Part of this due to the relatively low steam temperature requiring special turbines, and part of the cost is due to, well, the mind set of Asseltine.

#### gmax137

georgia psc votes to continue construction of plant vogtle:

More details
http://www.post-gazette.com/powersource/companies/2017/12/21/Remaining-Westinghouse-nuclear-project-will-continue-Georgia-regulators-rule-Vogtle-AP1000/stories/201712210105

The commission’s conditions in keeping Vogtle alive include a lower return on equity for Georgia Power, a division of Southern Co.; more money returned to ratepayers; a 5 megawatt solar array on plant property; and the possibility of reexamining the project once again if Congress doesn’t extend a production tax credit for nuclear power past its 2021 expiration date. Vogtle’s current in-service date is beyond that.

#### minerva

The criterion that utilities need to be sensitive to the requirements of investors is quite important, as Anorlunda so correctly points out.
It acts as a reality check on the system, something often lacking in government administrations.
In nuclear, we now have several examples of financially hugely damaging operational and political developments tied to the current concept of nuclear power plants.
For US investors who have suffered the consequences, pointing to on schedule, on cost plant constructions elsewhere does not help. They will not buy this package any more, the risk/reward here is unacceptable.
It remains to be seen whether the industry still can muster the industrial and political capital to successfully reinvent itself.
There are still big plusses to nuclear, relatively very low environmental impact and no CO2 emissions, very reliable baseline power, low operating costs.
If it can be made more accident proof and easier/quicker to build, that might be enough.
You're right, but I think you do have to have a little bit of regulation to guide the free market capitalism within certain boundaries to some extent. You can't just have everything "sensitive to investors" or they'll completely drive the climate and the environment into the ground with coal and gas combustion.

I know this sounds like the dirty word "socialism", but state ownership of the nuclear power build is what allowed France, for example, to deliver relatively fast, consistent and cost-effective deployment of a nuclear-based clean energy system at nation scale. The same goes for China, and the (originally state owned) power generation infrastructure such as the Snowy Mountains scheme in Australia. The Tennessee Valley Authority is another pertinent and interesting example too.

It's clear that there is real room for improvement with the economics and delivery of new US nuclear power projects. Just look at US nuclear power projects, and compare with say France, or China, South Korea, Taiwan etc and look at their delivery timelines and costs for relatively new nuclear projects. Or look at nuclear power in the US recently, and compare the costs to nuclear power in the US 40 years ago. (This is another reason why it's so important to keep existing plants open - a new US nuclear power plant isn't financially equivalent to an existing, already paid for, plant. Not by a long shot.)

What happened? What went wrong? These are valuable questions, and they're important to ask. They have been asked in the literature - for example Bernard Cohen's The Nuclear Energy Option, or Richard Rhodes' Nuclear Renewal. It has been recognized for a long time that this is a real problem that needs attention. Why are the costs out of control? If we can get US nuclear power back to where US nuclear power was decades ago, we'll be doing well. Part of this is due to the loss of momentum - the loss of the skilled industrial base with familiarity and practice in nuclear power construction.

Part is due to regulatory ratcheting - but nobody is saying there should be no regulation, or that safety and regulation are incompatible with cost-effective nuclear power. (This includes conventional LWRs, without radical technical changes to what a nuclear power plant looks like.) Nations such as France, China, South Korea or Taiwan deliver relatively fast, cost-effective nuclear power builds, but they do have standards, they do have government regulation of nuclear safety, and they do deliver very safe nuclear power which never hurts anybody, just like the United States.

"Highly improbable"?

Let's think about this for a bit from a perspective of "If I would want to blow up the plant, and have \$1B to finance it?".
How would one do it? Can this be done?
How much would it cost to hire or train 30-something squad of terrorists? To arm them with plenty of automatic weapons, sniper rifles, RPGs, breaching charges? Maybe even add a mortar team and a chopper with a machine gun.
I bet a lot less that one billion dollars.

You seriously think plant security is ready to face a real military assault team? After spending a decade doing only drills, not any real combat?

And if the attackers do defeat the defending security forces, blowing up a hole in concrete is almost trivial in comparison, especially that they know beforehand that they would need to do that - the physical parameters of nuclear plants are hardly a secret.
OK, suppose you have your highly skilled, heavily armed terrorist army.
You go to the local nuclear power plant. You neutralize all the plant security and local law enforcement.

Now, what are you going to *do* at the nuclear power plant, where and how?
And what will happen, what will the effect be?

And with your resources, weapons and skilled soldiers, and a hypothetical determination to inflict death and evil on the United States (or pick whichever nation) as much as possible, what makes you think that targeting a nuclear power plant delivers good "bang for your buck" compared to targeting a chemical plant, oil refinery, crowded mall or national landmark, stadium, etc?

A nuclear power plant is the worst choice, and soft targets with larger consequences are much more abundant.

Color me skeptical.

I recall a case where protesters, one of them a nun, managed to come to a nuclear weapons plant's wall and bang on it with hammers for half an hour, and only after that they were arrested. Googgling...

https://www.theguardian.com/world/2014/feb/19/nun-jailed-break-in-nuclear-plant

Aw, I'm wrong. Not half an hour. "They were able to spend more than two hours inside the restricted area before they were caught".
The Y-12 thing really isn't relevant to nuclear power.

They never had any access inside any buildings, or access to the vaults inside those buildings where HEU is stored, etc.

I suspect the security contractors at Y-12 were able to rapidly identify the "threat" as unarmed, nonviolent flower power protesters and not armed commandos, and they triaged their response accordingly.

#### mheslep

Gold Member
Since the release of the UK Draft National Policy Statement for Nuclear Power Generation, some 18 GWe of new gen 3 nuclear is planned in the UK, most of it to start construction by 2019. Four different designs are proposed, AP1000, EPR, ABWR, Hualong One. I suspect that design mix is two or three too many for economic success. If the French nuclear build-out in the 70s and 80s is any guide, success comes from building 50 reactors of one design (Areva PWRs in France), three size options, period.

#### jim hardy

Gold Member
2018 Award
I suspect that design mix is two or three too many for economic success. If the French nuclear build-out in the 70s and 80s is any guide, success comes from building 50 reactors of one design (Areva PWRs in France), three size options, period.
One design sure simplifies spare parts inventory and training of operations & maintenance folks.

#### Jon Richfield

...suspect that design mix is two or three too many for economic success. If the French nuclear build-out in the 70s and 80s is any guide, success comes from building 50 reactors of one design (Areva PWRs in France), three size options, period.
Agree in general, but would add that I hope they learnt something about passively fail-safe design from the Fukushima fiasco. Novel and obscure principles such as avoiding reliance on external or fallible local power supplies and active devices.

Costly? Count the cost and compare it with the cost of lost land, infrastructure and other resources, never mind human life quality and lives and minds and political support, then come back and tell me about passive scramming, fuel dumping and similar costs.

#### nikkkom

OK, suppose you have your highly skilled, heavily armed terrorist army.
You go to the local nuclear power plant. You neutralize all the plant security and local law enforcement.
Now, what are you going to *do* at the nuclear power plant, where and how?
I would open the containment (say, by blowing up a hole in its wall), haul a few tons of C4 under the reactor (which by this time would presumably be in a shutdown state and on emergency cooling), and blow it up.

And what will happen, what will the effect be?
Major release of fission products and actinides. Several tens to hundreds of square kilometers rendered uninhabitable for about a century.

#### mheslep

Gold Member
Agree in general, but would add that I hope they learnt something about passively fail-safe design from the Fukushima fiasco. Novel and obscure principles such as avoiding reliance on external or fallible local power supplies and active devices.
Agreed.

Costly? Count the cost and compare it with the cost of lost land, infrastructure and other resources, never mind human life quality and lives and minds and political support, then come back and tell me about passive scramming, fuel dumping and similar costs.
Seems clear to me that 1000 year tsunami risks and their consequences are far preferred over the ongoing alternative and its *daily* consequences:

Sydney (Platts)--3 Feb 2017 100 am EST/600 GMT

Japanese companies are planning to develop about 45 additional coal power plants in the next decade, as the country gradually ramps up its nuclear power generation following the Fukushima disaster in 2011, the US Energy Information Administration said Thursday
Replacement for idled nuclear: 14 new coal plants under construction as of July 17, and over 40 either announced, permitted, or under construction.

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#### mheslep

Gold Member
Major release of fission products and actinides. Several tens to hundreds of square kilometers rendered uninhabitable for about a century.
For about three months, the time for I 131 (half life 8 days) to decay out. Afterwards, the received dose is about that of an extra CT scan (10 mSv) spread over years, hardly uninhabitable.

Geraldine "Gerry" Thomas is a senior academic and Chair in Molecular Pathology at the Faculty of Medicine, Department of Surgery & Cancer, Imperial College London. She is an active researcher in fields of tissue banking and molecular pathology of thyroid and breast cancer.[1] Thomas is also a science communicator and has written opinion editorial pieces and provided comment to the media following the Fukushima nuclear disaster.

#### nikkkom

For about three months, the time for I 131 (half life 8 days) to decay out. Afterwards, the received dose is about that of an extra CT scan (10 mSv) spread over years, hardly uninhabitable.
I'm talking about Cs-137 and Sr-90, of course. If freshly shut down RPV would be blown up, the end result will be worse than Fukushima and approaching Chernobyl: open-air meltdown.

#### mheslep

Gold Member
I'm talking about Cs-137 and Sr-90, of course. If freshly shut down RPV would be blown up, the end result will be worse than Fukushima and approaching Chernobyl: open-air meltdown.
I don't think so. The Chernobyl reactor spiked to 30 GW before it destroyed itself. No amount of C4 can reproduce the nuclear power level delivered inside that reactor. The Fukushima accident involved three destroyed reactors. Also, the wide geographic distribution of Cs 137 comes about not because of some explosive force, but because it's parent fission product is Xenon, a gas which travels on air currents.

This also means BTW, that some of the new molten salt reactor designs which remove fission product gasses as an ongoing process would have less hazard potential even in the event of complete destruction of the reactor vessel.

#### nikkkom

I don't think so. The Chernobyl reactor spiked to 30 GW before it destroyed itself. No amount of C4 can reproduce that nuclear power delivered inside the reactor.
The purpose of explosives would be merely to crack RPV open and sever it from all piping. Then decay heating will do the rest.

The Fukushima accident was three destroyed reactors.
...inside intact containment.

Well-prepared nuclear terrorists can't be assumed to be so nice to leave containment intact.

#### jim hardy

Gold Member
2018 Award
I would open the containment (say, by blowing up a hole in its wall), haul a few tons of C4 under the reactor (which by this time would presumably be in a shutdown state and on emergency cooling), and blow it up.
I've only been underneath one RPV, my late 60's PWR.
The activity you propose is one of those "Sounds great on paper but....".
....................

Not arguing that knowledgeable punks couldn't make plenty of mischief. Hopefully 'knowledgeable' and 'punk-ism' are mutually exclusive.

old jim

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#### jim hardy

Gold Member
2018 Award
14 new coal plants under construction as of July 17, and over 40 either announced, permitted, or under construction.
What ? My Peabody stock might come back ?

#### nikkkom

I've only been underneath one RPV, my late 60's PWR.
The activity you propose is one of those "Sounds great on paper but....".
At my plant i doubt anything short of a "Bunker Buster" could blow a hole in the post-tensioned concrete containment building.
Today's run-of-the mill, light anti-tank RPG is designed to penetrate at least 500mm (half a meter) of rolled homogeneous armor. A few examples:
https://en.wikipedia.org/wiki/RPG-29 12 kg, 750mm RHA penetration, 1500mm reinforced concrete penetration
https://en.wikipedia.org/wiki/AT4 7 kg, 500-600mm RHA penetration

Custom-made breaching charges can do better.

#### mheslep

Gold Member
What ? My Peabody stock might come back ?
Not from US consumption. But if they mine coal in China, or in Australia where Japan gets its coal ...

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