3 ms·

There is a documentary on it somewhere that I watched many years ago. The main sticking point was the use of nuclear blasts to carve out water channels. For a b

There is a documentary on it somewhere that I watched many years ago. The main sticking point was the use of nuclear blasts to carve out water channels. For a brief time after WW2 this seemed like a good idea, but upon further reflection fell out of favor.

credit_guy 4y ago
But why? The Trinity test site was open to the public in 1953, less than 10 years after the blast took place. Nowadays, the radioactivity there is only 10 times the average natural radioactivity [1]. That may seem like a lot, but there are places in the world with much, much higher background radiation, and epidemiological studies failed to determine an increase in cancer rates or other health issues [2]. [1] https://en.wikipedia.org/wiki/Trinity_(nuclear_test)#Site_today https://en.wikipedia.org/wiki/Trinity_(nuclear_test)#Site_to... [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4030667/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4030667/
- saiya-jin 4y ago
  Would they wait for 70 years to let water in, to still get it irradiated 10x the normal background radiation? So that everybody, including small babies would drink it eventually? Or just say fuck it, progress is priority #1 and let the water in immediately, let the future generations solve the issues. Yeah, I really wonder why even Chinese decided to not go that way...
  - throwaway4aday 4y ago
    Considering that the CCP didn't sign the PTBT and conducted atmospheric nuclear tests until 1980, I doubt they give an f about that.
- deepsun 4y ago
  There's no such thing as relative comparison of "radioactivity". You cannot describe a radionuclide contamination by a single number. For starters, radioactive emissions come in three forms (alpha, beta, gamma), all with different properties. Different nuclides accumulate differently in living tissues too. There can be almost no elevated gamma background, but nevertheless harmful to live there (e.g. Chernobyl).
- thombat 4y ago
  Part of the answer is that atmospheric explosions generate a lot less fallout precisely because they move less dirt: that first link states that a 30m high tower was used in large part to minimise fallout and left a crater with maximum depth of 140cm. So "Trinity" 75 years later isn't a very good indicator of how atomic civil engineering on a short timescale will fare. It's interesting and perhaps a little reassuring that the 2009 review of natural background exposure didn't find conclusive effects other than for radon, but the enthusiasm in the US for peaceful nuclear explosions had already ebbed more than 40 years earlier after some quite cavalier experiments, so it's not so much "why is it unpopular?" as "why couldn't the topic be reconsidered in the light of newer research and less as a cheerleading exercise for nuclear weapons development?". Probably it's hard to judge the economics of PNEs Vs conventional civil engineering since the nuclear industry is quite coupled to the military.
  - throwaway4aday 4y ago
    Were they proposing surface detonations to dig the channels? From my limited knowledge of blasting, the conventional explosives are placed in holes drilled into the rock in order to fracture it so it can be easily removed. Would you not do the same with nuclear explosives but just on a larger scale?
    - thombat 4y ago
      That's exactly what you do, but that means some finely pulverised irradiated material probably gets ejected. The notorious example of this was the Sedan nuclear excavation test [1] which created a usefully big hole (100m deep, 390m diameter) by removing some 11 million tons of soil, but "the radioactive fallout from the test contaminated more US residents than any other nuclear test." Much of the fallout was due to the fraction of the yield that was from fission, and WP notes that "had this test been conducted after 1965 when improvements in device design were realized, achieving a 100-fold reduction in radiation release is considered feasible". But the public enthusiasm for the program was naturally impaired. [1] https://en.wikipedia.org/wiki/Sedan_(nuclear_test) https://en.wikipedia.org/wiki/Sedan_(nuclear_test)

credit_guy 4y ago

But why? The Trinity test site was open to the public in 1953, less than 10 years after the blast took place. Nowadays, the radioactivity there is only 10 times the average natural radioactivity [1]. That may seem like a lot, but there are places in the world with much, much higher background radiation, and epidemiological studies failed to determine an increase in cancer rates or other health issues [2]. [1] https://en.wikipedia.org/wiki/Trinity_(nuclear_test)#Site_today https://en.wikipedia.org/wiki/Trinity_(nuclear_test)#Site_to... [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4030667/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4030667/

saiya-jin 4y ago
Would they wait for 70 years to let water in, to still get it irradiated 10x the normal background radiation? So that everybody, including small babies would drink it eventually? Or just say fuck it, progress is priority #1 and let the water in immediately, let the future generations solve the issues. Yeah, I really wonder why even Chinese decided to not go that way...
- throwaway4aday 4y ago
  Considering that the CCP didn't sign the PTBT and conducted atmospheric nuclear tests until 1980, I doubt they give an f about that.
deepsun 4y ago
There's no such thing as relative comparison of "radioactivity". You cannot describe a radionuclide contamination by a single number. For starters, radioactive emissions come in three forms (alpha, beta, gamma), all with different properties. Different nuclides accumulate differently in living tissues too. There can be almost no elevated gamma background, but nevertheless harmful to live there (e.g. Chernobyl).
thombat 4y ago
Part of the answer is that atmospheric explosions generate a lot less fallout precisely because they move less dirt: that first link states that a 30m high tower was used in large part to minimise fallout and left a crater with maximum depth of 140cm. So "Trinity" 75 years later isn't a very good indicator of how atomic civil engineering on a short timescale will fare. It's interesting and perhaps a little reassuring that the 2009 review of natural background exposure didn't find conclusive effects other than for radon, but the enthusiasm in the US for peaceful nuclear explosions had already ebbed more than 40 years earlier after some quite cavalier experiments, so it's not so much "why is it unpopular?" as "why couldn't the topic be reconsidered in the light of newer research and less as a cheerleading exercise for nuclear weapons development?". Probably it's hard to judge the economics of PNEs Vs conventional civil engineering since the nuclear industry is quite coupled to the military.
- throwaway4aday 4y ago
  Were they proposing surface detonations to dig the channels? From my limited knowledge of blasting, the conventional explosives are placed in holes drilled into the rock in order to fracture it so it can be easily removed. Would you not do the same with nuclear explosives but just on a larger scale?
  - thombat 4y ago
    That's exactly what you do, but that means some finely pulverised irradiated material probably gets ejected. The notorious example of this was the Sedan nuclear excavation test [1] which created a usefully big hole (100m deep, 390m diameter) by removing some 11 million tons of soil, but "the radioactive fallout from the test contaminated more US residents than any other nuclear test." Much of the fallout was due to the fraction of the yield that was from fission, and WP notes that "had this test been conducted after 1965 when improvements in device design were realized, achieving a 100-fold reduction in radiation release is considered feasible". But the public enthusiasm for the program was naturally impaired. [1] https://en.wikipedia.org/wiki/Sedan_(nuclear_test) https://en.wikipedia.org/wiki/Sedan_(nuclear_test)