Back in the 1950’s many projects (a new Panama Canal), Isthmus of Kra Canal, were proposed-excavated by nuclear explosions. Of course, these were abandoned when it became obvious that radioactive fallout would make such projects too dangerous.
I wonder if research into nuclear explosives has continued-is it now possible to make bombs that produce small amounts of fallout (so that excavations with them would be safe)?
WAG: No.
My opinion is the fallout can’t be avoided in excavations. The fallout comes from the material the nukes blow out of the ground and irradiate. The whole point of excavation is to move dirt. If you want to move dirt with nukes, some of that dirt will become radioactive crap that falls out of the sky and onto our own planet.
Ray-dee-ayshun. You hear the most pernicious nonsense about radiation…
The catch is that cratering detonations are the very worst in terms of fallout- the Sedan shot in 1962 that was part of Operation Plowshare, was the highest in terms of fallout of any of the continental US nuclear tests, and only created a 100m x 400m crater.
It would take many, many explosions like that to excavate anything worthwhile that couldn’t be done with conventional explosives and earthmoving equipment.
I’m a little baffled as to what kind of “research” will somehow enable us to disappear several tons of radioactive dirt blown into the atmosphere.
As mentioned already, the fallout issue is the unavoidable killer. They not only talked about excavating a harbor in Alaska or a canal through Panama or Nicarague – they were thinking of setting off a bomb underground in Pennsylvania (!) as part of Project Gasbuggy. The idea was to stimulate the outpouring of natural gas. (Note to opponents of “fracking” – it coulda been MUCH worse).
The problem, again, was radioactivity – the natural gas would have been heavily laced with radioactive material, and unusable.
The Priohect Sedan crater, which was what they set off in Nevada when they couldn’t get approval for setting off a bomb in Alaska, is still dangerously radioactive.
And, jusdt for kicks, they found out many years later that someone had dumped some radiactive material at the proposed site of Project Chariot in Alaska, apparently to see how the radioactive material migrated through time. They didn’t tell the local folks about this. See the book the Firecracker Boys.
I used to drive by one the of Gasbuggy wells in northern New Mexico on my way to work. Not only did it turn the sand stone to glass and create an impermeable barrier to flow but there are still issues with producing that formation to this day. So they weren’t just thinking of it they actually did it twice.
Yreah, but they didn’t do it in Pennsylvania – that’s what I meant by "they were thinking of it.
Wait a minute. “Let’s stimulate the outpouring of natural gas” - with a large explosion???
And not one person thought up front how this was stupid on epic levels?
Nope. They were desperate to find “peaceful” uses for the atomic bomb. You could as easily say the sme about the Project Plowshare atomic excavation project. When I first heard about these, my immediate reaction was – “That won’t work – there’ll be way too much radiation and fallout.” Surely they knew this far better than I did.
But Teller, for one, was obsessed with proving the utility of peaceful nukes, and pushed very hard for Project Chariot and its blasting of a deep harbor in Alaska with five bomnbs. Even though the local residents wanted nothing to do with this. And even though nobody had a conceivable use for such a harbor (this was long before the Arctic reserves were characterized, or even feasible). see the Firecracker Boys
http://arcticcircle.uconn.edu/SEEJ/chariotseej.html
http://arcticcircle.uconn.edu/VirtualClassroom/Chariot/vandegraft.html
This thread makes me want to sign off saying…
-Excavating (With A Nuke)
I love the fact that a typo on the congressional record led the Sudanese government to complain about the US conducting nuclear tests in their country 
I hadn’t realized that the “Miner, Forty-Niner” was from 1949!
I’m… not sure what this means exactly. My post was in reference to our good poster excavating (for a mind) who always ends his posts with his username.
I know pure fusion bombs don’t yet exist (or, if they do, they’re classified), but is there a thermonuclear design that can give more bang for a lower radioactive “buck?”
I’m not sure if “desperate” is exactly the right word, but yeah, there was significant pressure from the government (and significant funding) to develop some sort of peaceful use of nukes that we could point to. The purpose was, of course, not that we needed canals or harbors, but that we wanted to develop nuclear weapons and use some ostensible peaceful purpose a s a cover story to escape international opprobrium.
No, fusion weapons still require a fission trigger (a “pit,” in DOE parlance). Although fusion per se is cleaner than fission, you’d still have some radiation from fusion, and the pit itself is still fissile. In fact, the biggest bang of all comes from multi-stage weapons in which a fissile pit creates conditions that permit a fusion stage (typically tritium injection) which, in its turn, creates conditions that will fission a heavy outer shell, or tamper, of U-238 (the natural, un-enriched form) which normally will NOT fission outside of the extreme conditions the fusion stage created).
Current state-of-the-art is both classified and unknown to me, but Richard Rhodes described the Teller-Ulam multi-stage design in his book, Dark Sun, as getting the majority of its yield from the third stage (fission of the tamper). Note that fission of the U-238 is fairly dirty.
Since the point of using a nuke in the first place is supposedly to move huge volumes of earth, the really big yields would be necessary. The really big yields would seem to necessitate this relatively dirty design (with the fissile tamper stage), and of course all the earth moved would be contaminated and dispersed into the environment (a politer term than saying “your children.”)
I’ve sometimes wondered about using nuclear “excavation” by producing subsidence craters, wherein the blast (and fallout) is actually contained underground, instead of just blowing the crap out material out of the crater.
Indeed, a quick check online indicates that the Soviets did possibly conduct some tests along those lines, for the possibility of building reservoirs. Although, as I guessed, local geology is the deciding factor in if the effect can be pulled off, limiting it’s use.
even if they did, the neutron flux from it would make anything it touches radioactive
“Anything”? Now, I have to ask…how bad would the radioactivity from neutron capture be in a nuclear excavation, assuming you used a pure fusion weapon? (However you managed to build one, without a fission primary…hauling a giant laser out to the dig site might be slightly impractical.)