If you were a movie-like villain and had physical access (and knowledge of) to every system of the plant, could you orchestrate a powerful steam explosion that would send huge amounts of radioactive/irradiated particles into the air, or maybe there are physical hurdles in the way that would make it impossible?
I’m taking about modern nuclear reactors that are currently in use.
If you just have access to the control room, I think it would be extremely difficult. But if you could monkey around with the actual hardware, say loosen some bolts here and there, or even blow up some shit with small charges, then maybe.
I’ll ask my dad later tonight at dinner. He just retired from Westinghouse a few yrs ago working as a nuclear plant safety systems engineer for the past 40 or so yrs.
It’s hard to imagine a lone person, regardless of their access being able to do more damage than the tsunami did to (an older, less capable, less safe) plant like Fukushima, and that hasn’t exactly been on the scale you apparently are talking about. I suppose, in theory if you had exclusive access with no one else there and days to set it up (plus you didn’t mind the high probability you’d die), it’s theoretically possible. But it’s not very plausible. Contrary to what seems to be popular belief, even the older designs we are currently working with are really, really safe and very difficult to use as a mass dirty bomb.
Fukushima killed about zero people, directly.
Chernobyl about 30.
If someone has the ability and expertise to cause a malfunction in a reactor, despite all the safety precautions, they might as well forget terrorism and turn legit.
Some years ago I toured a major nuke, and terrorism was a big part of the discussion. I was quite impressed with the systems in place to deal with just about anything you could think of. There are much softer targets.
I don’t think there are any modern ones in use.
All the functioning nuclear plants are using technology that is years, even decades old. If we built a new one, we wouldn’t use those designs at all.
You could get the same effect as a dirty bomb.
That is to say, if you had that kind of access, you could probably cause an incident that was bad enough to incite a lot of panic, without actually causing any notable amount of damage. Which is also what a dirty bomb would do.
If you had authorized access to the plant, and were able to sneak in explosives - which doesn’t sound hard, there must be pallets of equipment and materials being moved in and out of a nuclear plant on a daily basis - I think an incident similar to Fukishima would be pretty easy to cause.
Fukishima happened because the following events happened :
a. Loss of primary power
b. Loss of backup power
c. Delay in restoring a & b
d. Loss of coolant
e. Faulty containment shell
Once (d) happened, and enough coolant was lost, and the cladding around the nuclear fuel melted off, it was unfixable. The reason is that the radioactive steam that dirties up the primary loop makes it deadly to enter the containment dome at all to fix anything.
How does a terrorist cause the same accident?
a. Bomb on the substation(s) that provides electric power to the plant. It doesn’t need to be a very large bomb - very large transformers like that take days to repair
b. Bomb on the power distribution panel, ideally thermite, for the backup diesels.
Thermite will melt buses together and cause arc flashes and essentially require rebuilding the electrical panel.
c. Bomb on one of the lower standpipes that comes out of the core carrying coolant. This bomb needs to be a shaped cutting charge and a fairly big one.
This would cause very rapid loss of coolant for the reactor, within minutes. The other 2 bombs cut the power for the coolant pumps. Once the zirconium around the nuclear fuel rods vaporizes, the broken pipe underneath the reactor can’t be fixed by humans (or even robots, it seems) and neither can the power panel to the pumps.
Yes, there are armed guards. I suppose it would depend on how many are really at a given reactor, but it seems like something a vanload of terrorists could achieve if they knew where the guards were stationed.
Basically, the terrorists mow down the guard at the main gate, open it up, drop off 1-2 terrorists with RPGs or just thrown bombs with short timers. They toss bombs into the power substation transformers and blow them up. The main assault team charges the building, shooting any remaining guards on the way, and they then split into two teams, one that will bomb the power distribution panels and one that will go for the coolant pipes.
Basically, unless there’s a fully equipped defending team - you know, experienced soldiers with body armor and long guns - waiting in ambush to protect the place - that reactor is done for. The local swat team might be 20 minutes away, but it wouldn’t matter.
Or if the terrorists are incompetent - realistic examples of terrorists in the last couple decades, with one very notable exception, have not been very skilled or capable of executing such a plan.
Reactors could be designed and sited to minimize the damage from such an attack*. But the actual plants in service aren’t designed for this, and apparently such an attack would cost hundreds of billions of dollars in damage.
*chiefly by planning the basement to handle the core melting down, the containment shell to handle a melted core, and siting the reactor far from populated areas.
I know someone who’s done work with Homeland Security, specifically at nuclear plants. Obviously, I know no details about what sorts of security and precaution they take, but it does mean that DHS takes such a potential threat pretty seriously.
SamuelA - your reply is oddly specific, did you base it on some report or something?
I believe nuclear plants are still being built, also “decade old deigns” still sound fairly modern to me, I’m mean they are not computer chips to be updated every year 
SamuelA- why do you need to cut primary and backup power to the coolant pumps if you are going to destroy the cooling loop in massive way?
Would not just doing point C prevent effective core cooling and lead to the same outcome?
Or are there secondary cooling systems in place?
Primarily, at Fukishima, the accident showed that only loss of electric power, no other damage, is enough to cause such a disaster. So other than blowing a hole in the cooling loop, loss of power is going to prevent any efforts to fix things.
With the pumps still working and valves still working and the control switches still working and there are emergency sprinklers that can spray water inside the core, and the lights still on inside containment building, it may be possible for the plant crew to bring things under control after the SWAT team comes and cleans out the terrorists.
It’s all about time - if the crew can keep the fuel rods from actually getting so hot that the fission products come out, even the primary loop water is not going to be very radioactive. You can send someone down there and they can block the broken pipe. Then reconfigure the valves or repurpose other pumps to keep enough coolant flow through the core. This was demonstrated effectively in the response to the K-19 submarine meltdown - though they did this too late, after the steam was lethally radioactive…
If it’s in the dark, and key parts of the power distribution panels are inside the containment dome which is going to fill with lethally radioactive steam, yeah, it’s not happening.
See this book: Rad Decision.
Essentially in this novel, a terrorist sabotages the backup diesels and the dual power substations (one from each grid) going into the plant. I think he did one more thing, would need to pick up the book again.
The terrorist performs the sabotage in a way that is indistinguishable from a fluke accident. (the substations are just shorted by balloons with strings)
Thanks to quick actions by the plant’s crew, they are able to prevent a meltdown, but this relatively small bit of sabotage leads to destruction of the reactor’s core. It’s the same reactor design type as Fukishima’s.
I have to wonder if a how-to guide for this topic is a good idea.
Those who want to break things don’t need a how-to guide.
Those who want to prevent people from breaking things need to know where their vulnerabilities are.
Also it lets you do a comparative analysis. With one “vanload of terrorists”, how much damage can they do to a wind farm? A solar park? A natural gas turbine plant? A coal plant?
One thing you will immediately note is that in most cases, the terrorists at most can just wreck some equipment, which costs mere millions or tens of millions, and will need to be replaced. They can gun down a few people but they could gun down people just anywhere - there’s no effect multiplier.
If the terrorists were to successfully cause another Fukishima, they’d do more than a half trillion dollars worth of damage and leave a huge area of land uninhabitable for many years. (aka about as much money as the annual operating budget of the entire U.S. military)
The gas turbine plant, from the above examples, is the most vulnerable because it would be possible to create a gas leak and set up the conditions for a decent sized explosion. Might kill some first responders and the crew of the plant who were surviving.
And the plant would then need replacement. But, you know, the fire would burn itself out, after cutting off the fuel supply pipelines, in a few hours. The wreckage would be cool enough to start rebuilding in a day or two.
Not 100 years.
Deaths aside, the social and economic costs of Fukushima and Chernobyl were far from negligible. These costs alone would make causing a similar disaster tempting for terrorists.
I don’t see how you get around the problem of location. A dirty bomb is going to be most effective if you set it off in a downtown area, not so much because of immediate destruction, but the fact you can’t reoccupy the area until clean up is complete. That will not only cost a fortune but the disruption to the economy may very well dwarf the direct cleanup cost. If you blow a plant 15 miles away, it’s a disaster, but downtown would be a mega-disaster.
Not really? It’s about quantity. If someone stole a few cobalt-60 sources or other intensely radioactive substances and blew them up downtown, it would be hard to clean up the dust. But ultimately it would be just a few pounds and you could probably pressure wash off the debris from armored vehicles or something. Also, it would be trivially easy to detect where the dust went and if cleanup was adequate or not.
A reactor core has a hundred tons of more of intensely radioactive material, and if it melts down, fission can continue in some circumstances, creating more heat and more fission products.
Either way, it’s not about killing people. In either situation, just a handful of people would die, no more than an equal number of terrorists could just gun down in an everyday mass shooting. But thousands more would have an increased risk of cancer and millions would live the rest of their lives in fear.
And it’s also about the economic damage. If Fukishima’s total tab really is 600 billion dollars, that’s one heck of a weapon of asymmetric warfare.
There’s no way a dirty bomb could shut down a city for a hundred years. Hiroshima was destroyed by an actual nuke, and it was back to its pre-bombing population level in just 13 years.