Nuclear reactors and pollution

[Kurushio]

This may have been discussed before, apologies if it has. Though I wanted to know: what happens if a nuclear sub goes down near a coastline? Let's say 200 miles off the coast of an inhabited coastal town/beach resort and say 500 metre depth? Would the radioactive slick be lethal? And at what range?
Would the salty sea water combined with the pressure be enough to subdue any real pollution?

Must've been quite a dillema trying to stop Soviet boomers reaching American shoreline in the Cold War. Or was it? :hmm:

[Molon Labe]

I think all the nuclear fuel tends to clump together and is heavier than water, so unless something happened to the reactor itself, the impact to the environment of a sub going down should be minimal.

The US does periodic environmental studies in the areas where Thresher and Scorpon went down, and haven't discovered anything "bad" yet.

[Kurushio]

http://photobucket.com/albums/b58/schema84/th_orly_owl.jpg

I was about to make the thread about how unrealistic it was getting orders to take out a nuc near the shoreline...so that's actually very good to know. Thanks. :rock:

p.s. Sorry about the orly owl...I've always wanted to use it...at least once. :yep:

[Kapitan]

Submarine komsomolets has been at the bottom for 17 years and no radiation leakage she sits near the norwiegen coast.

K8 sank near the western approaches 1970 no reported issues.

The nuclear fuel would have to melt down to make any form of contamination, even then it wouldnt be muchnothing like chernobyl fall out because the melted core would cool in the sea water a bit like a volcanos lava.

Also the fuel is house ina submarine that has a sealed compartment that also has a water and air tight reactor so whats the odds ?

[Henson]

The 'runaway reactor' scenario that we all read about in Clancy's book is supposedly impossible in US boats. I can't speak for russian, indian, or french reactors, but the US reactors 'default' to shutdown state. They basically have to be forced into a critical state ('critical' in this case simply means running, not emergency).

I could be wrong, but that's what the nucs told me during ship's quals. Any nucs here to elaborate?

[Kapitan]

Should a certain amount of trip switches be tripped the russian reactors are designed to shut down by them selves in some cases rods have been wound down by hand but its normaly nessasery.

During an emergency fire or what should the crew need to shut down there reactor there are switches in all compartments.

[TLAM Strike]

I think they are going to build a big cement tomb over the Komsomolets or K8 at some point rather than risk contaminating the rich fishing zones near where they sank.

[Bubblehead Nuke]

How to discuss this, and not break any rules.....

Okay, the control rods, when de-engergized, revert automatically to a fully inserted position. This is ALL the control rods, not just the SCRAM group. There is sufficient nutron attentation to adequately ensure a core shutdown even if one or 2 where to 'stick' at some position not corrosponding to full insertion.

The reactor vessel is probably the single strongest component on the submarine. In a hull collapse the primary cooling lines will, in all proabability, be severed from the contaiment vessel. This will make the vessel non-collapsable as internal pressure will be equal to sea pressure. This is important for as long as the containment vessel is intact the control rods will be maintained in the proper configuration to ensure continued core shutdown.

The worry then is corrosion of the fuel matrix and the subsequent release of radioacive material. Again, as long as the containment vessel is intact this should not result in the significant spread of contamination as any corrosion products should be maintained inside the containment vessel.

The corrosion of the containment vessel, due to the nature of the materials used, will be very slow. If the vessel lays at a considerable depth the corrosion rate will be further reduced by the low free-radical and oxygen content of the seawater at extreme depths. If it is in shallow water where corrosion can be a significant factor then means can be made to bring the containment vessel to the surface. Remember, we once dang near raised a Golf class sub many years ago. The reactor vessel is significantly smaller and lighter than a sub

With that being said here is another thought track.

If the submarine in question were to be damaged, say by a torpedo, and the reactor vessel is ruputed distupting the control rod configuration. Well, that would be bad. With no control rods the reactor would pretty much be uncontrolled and the resulting fission products would be scattered to the seas and currents. We are talking Chernobyl of the seas here. Massive contamination on the order of months and years. On the bright side, that is an absolute worse case. It would be an incredible lucky (unlucky??) explosion that would disrupt the control rod configuration and NOT disrupt the core configuration so much that criticality could be maintained on any small scale, let alone a scale large to make significant measurable contamination.

[Bubblehead Nuke]

During an emergency fire or what should the crew need to shut down there reactor there are switches in all compartments.

My GOD. What an incredibly stupid design . One man, who did not know the true extent of a causality, could shut the reactor down, limiting propulsion, electricity, manuverabilty. I can think of a dozon causualties off hand were shutting down a reactor would take it from the managable to possible, if not certain, Loss of Ship.

Sorry for the caps but I know any ex nuke submariner just got the shakes READING that

[Kapitan]

The russian reactors are nothing like the american ones, there has been reactor shut downs in the past but its a safty feature in the reactor to stop anything bad happening. not sure if its implemented in the new builds but it is in submarines like the Victor III Akula's oscars deltas and phoons.

http://i7.photobucket.com/albums/y262/russian-navy01/OK650B.jpg

And here is the nuclear reactor of a typhoon class SSBN reactor designated 0K-650B pressureised water cooled.

[Henson]

Once again....my GOD.

[Kurushio]

Wow...I'm in awe at you guys amd your knowledge :know: (and slightly jealous!).

Though as Bubblehead Nuke said, if there is a danger there could be pollution if the sub is torn apart in an explosion...do they design torps so it doesn't destroy the sub but just damages it enough to make it sink?

...also related...has anyone ever seen a photo of a nuclear torpedo exploding underwater? Would love to see one...or it's effects on the surface.

[TLAM Strike]

...also related...has anyone ever seen a photo of a nuclear torpedo exploding underwater? Would love to see one...or it's effects on the surface.

Well this is a nuclear depthcharge deployed from an ASROC.
Test "Sword Fish"
http://img4.imageshack.us/img4/3739/dswordfish3b1uw.jpg
Note the ship in the image was used to test how much it would be affected by the blast, it was unharmed.

I don't think the US ever test detonated the ASTOR. For a torpedo the only thing I could think of would be a Russian test and the odds of finding an image of that are quite low.

[Sub Sailor]

I guess it is possible a torpedo could crack or possible break the Reactor Vessel, but most unlikely. The vessel itself is a huge chunk of metal and it is further contained in the shield water tank.
It is without a doubt the single strongest component on the boat. The designed safety factors in US Reactors are actually way overkill. Scorpion and Thresher's vessels are still intact. I don't even know how long before they would leak fuel.
US Reactor Compartments are sealed and locked at all times, except in an emergency. In the old days we used to discharge resin beds before entering the ship yard, but not anymore. That is the only time I ever entered the Factor Compartment at sea. Of course the plant was shut down.
The control rods, as BH explained fail safe, and the plant was designed with stuck rod(s) planned in. I never encountered a stuck rod. Supposedly we could operate with (some) number of rods stuck out.

Ron Banks MMCM(SS), USN(Ret)
a really old nuke, 1962-1981. All Subs

[Sub Sailor]

Reactor Compartment.

Sub Sailor :oops:

[Bubblehead Nuke]

The russian reactors are nothing like the american ones, there has been reactor shut downs in the past but its a safty feature in the reactor to stop anything bad happening.

They are more alike that you imagine. Yes, I know a lot about them. It was a hobby so to speak. The main difference in the reactors is fuel enrichment and power density. All the rest is cosmestic and/or different design philosopies. You have the same basic engineering problems and goals. The Russians had some unique solutions to some problems. Some worked better than ours IMHO.

What I was talking about was operational procedure. Now there are some MAJOR differences in how American and Russians run thier boats. Having a switch locatation all over the boat that could scram your reactor is just inviting trouble IMHO. LIke I said, someone in one compartment can have a brain fart and mis-interpret a casualty, SCRAM your plant, and then make a managable caualty a life or death game of catch-up.

[Alpha]

The wonderful thing as though with a nuclear reactor is that the radiation is contained underwater. ie: the Control rods in a reactor, are highly radioactive and are placed underwater. The water acts as a shield for the radiation people can walk around in the room where the reaction takes place without ever being exposed to nuclear radation. So if a sub like that was to go down in an area of around 500 meters or around 1650 feet, the radation should be contained underwater and shouldn;t ever affect the people on the island. However "greenpeace" is going to be unhappy seeing as how many fish and other water wildlife will proably die. I figure that would be kept classified if it ever happened.

[Kapitan]

You probably know more about the reactors than me, of all the russian submarines i have been on board im not allowed to view any engineering machinary.

[SeaQueen]

Though as Bubblehead Nuke said, if there is a danger there could be pollution if the sub is torn apart in an explosion...do they design torps so it doesn't destroy the sub but just damages it enough to make it sink?


It's actually unclear exactly how much you really need to sink a submarine. If you just rattle it enough so that a the right pipe breaks at the right depth, you won't even have to pierce the hull. By the same token, submarines are typically quite hardened, intended to withstand nearby nuclear explosions. Exactly how the likelihood of the weak components and the strong components failing catastrophically plays out isn't exactly clear.

[Bubblehead Nuke]

Though as Bubblehead Nuke said, if there is a danger there could be pollution if the sub is torn apart in an explosion...do they design torps so it doesn't destroy the sub but just damages it enough to make it sink?


It's actually unclear exactly how much you really need to sink a submarine. If you just rattle it enough so that a the right pipe breaks at the right depth, you won't even have to pierce the hull. By the same token, submarines are typically quite hardened, intended to withstand nearby nuclear explosions. Exactly how the likelihood of the weak components and the strong components failing catastrophically plays out isn't exactly clear.

There was a 688 that was intentionally depth charged with explosive devices at various ranges and with various amounts of explosives in order to test this very point. It was called 'Shock Testing'. Granted, this was done at periscope depth (they used the scope as a reference point on when to detonate the explosives at the proper time and range). From what was heard about it, there were some rather large explosive packages used.

From what I understand there was some REALLY impressive film footage from inside the sub as things moved and such. Scuttlebutt has it that one of the test runs removed the upper hatch of the weapon shipping hatch. At that point they said enough was enough.

How big were the charges and how. close to the hull were they? I can not say.

This link: http://www.epa.gov/fedrgstr/EPA-IMPACT/1999/January/Day-21/i1308.htm

Talks about using 1000 lb charges to test the Seawolf class in shock testing.

[Kurushio]

Thx for all the responses...very interesting reading. I never actually knew nuclear depth charges existed. :o

[SeaQueen]

How big were the charges and how. close to the hull were they? I can not say.


It's most likely classified. It you knew that, you could design a better torpedo to from it. :-)

I know that the NSWC in Carderock, MD used to have a pool for doing scale model testing of this sort of thing. I took a tour of that when I was a scout, and when they detonated the charge to demonstrate for the crowd, I nearly jumped out of my skin!

I suspect that someone probably has a fairly good idea of what it takes to sink a sub from various engineering tests and computer models. I know that the probability of failure for situations where there is a weakest link follows the Weibull distribution. It would make sense to me that the engineering testing would be designed to fit parameters to that distribution, as well as to identify points of failure and try to harden them.

There's also some other stuff I've seen, but can't really talk about here.

[SeaQueen]

I never actually knew nuclear depth charges existed. :o

At one point, they were the primary ASW weapon in the USN's arsenal. Other nations had them as well, even nations that were officially non-nuclear, such as the Netherlands. The ASROC and SUBROC were primarily nuclear weapons. My boss started his career studying the effects of nuclear depth charges and nuclear tipped cruise missiles.

I think sometimes people like to make themselves feel good and think, "Awww... it never would have really gone nuclear." The truth is if WWIII happened, it'd would have become a nuclear conflict almost immediately. It probably would have been nuclear at sea before it was nuclear on land too, I think, simply because nuclear weapons make very natural weapons of ASW.

As time goes by, that mindset seems to fade, and real horror of what the world was faced with in the Cold War becomes romanticized or forgotten.

I think the thing that will ultimately make nuclear weapons obsolete will almost certainly be precision guided weapons. At this point, there's a lot of talk that the proper response to a nuclear attack might actually be a precision conventional strike. They really are that powerful, but focused. They're also more verstatile in a lot of ways. If there is a second best choice to a peaceful world, I suspect it might be a world where those conflicts which do exist are confined to willing participants. In Africa, there's a saying, "When elephants fight, the grass suffers." It is never more the case than with nuclear weapons.

[Deathblow]

...also related...has anyone ever seen a photo of a nuclear torpedo exploding underwater? Would love to see one...or it's effects on the surface.

Various nukes with some underwater test: http://www.break.com/index/nuclearpower.html

Underground nuke test just for kicks: http://www.break.com/index/nuketest.html

[Kurushio]

Wow....those nukes are pure evil. Gave me the shivers watching that... :huh: Good though.... :up:

[OneShot]

I think Einstein said this (well, something close to it) : "I don't know what weapons we will use in World War 3, but I am sure that the war after that will be fought with sticks and stones".

Fortunatly it looks like an all-out Nuclear war is not likely at the moment, tho we better not underestimate local use of (dirty) Nukes.

Anyway, as for the pollution, aside from the places where nuke subs have sunk, does anybody have a good idea how much the enviroment is contaminated in places like Tschernobyl, or the Nuke Test Ranges? I think there is more danger then from small capsuled, shut down, reactors.

[Molon Labe]

Heh, there's one patch of ground somewhere in the US where the nuclear engine for a sort-of drone/cruise missile aircraft was tested. It literally sprayed radioactive exhaust. Fortunately, it never left its concrete bunker in the desert.

[Bubblehead Nuke]

Heh, there's one patch of ground somewhere in the US where the nuclear engine for a sort-of drone/cruise missile aircraft was tested. It literally sprayed radioactive exhaust. Fortunately, it never left its concrete bunker in the desert.

Actually, it was a nuclear jet engine. Thats right, a jet engine. It used a reactor to heat the air (hence the reactor was air cooled) instead of compressors, fuel cans and all that. Plan was for it to go airbourne and pretty much stay there till they dropped the bomb. They had plans for inflight crew change and everything. They were going to use the old B-36 PeaceMaker.

Check out http://www.cowtown.net/proweb/nb36h.htm for a picture of the plane that actually carried a reactor on-board. Note: they NEVER actually flew the plane on atomic power, they only got as far as actually lighting one up in a bombay to test the thing while in flight.

Anyway, during a ground test of the actual engine, a thermocouple failed and they lost indication of ACCURATE core temperature. They had a material failure due to overheating and it SPEWED parts of the core out of the back. Luckily, someone had a clue and decided that these things spewing radiactive entrails over the U.S. would not be a polically correct thing to do and cancelled the whole project.

[TLAM Strike]

John Craven talks a little about this in his book, 'The Silent War'. ;)