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All Okay in Oklo

The search for a safe, reliable, low maintenance nuclear waste depository takes us to the Central African State of Gabon. The Oklo region of Gabon was home to several mines run by their colonial rulers France, who exploited and continue to exploit the rich uranium ores in Gabon and other African countries (a story for another day)http://www.bbc.co.uk/news/world-africa-21318043.

The French in 1972 discovered that there were discrepancies in isotope levels of Uranium-235 in the uranium coming from a particular Oklo mine (Davis et al., 2014). Discrepancies that mirrored what would happen to uranium ore in a nuclear reactor. After evaluating the journey the ore had undertaken French scientists realised that the only possible reason for this to be the case was that the uranium ore in Oklo had operated as a natural fission reactor, producing essentially nuclear waste that had been stored beneath the earth for billions of years. The reason this was possible was that the amount of Uranium-235 had been enough to sustain a chain nuclear fission reaction for about 800,000 years until about 1.8 billion years ago (Fujii et al., 2000).

This discovery was important as 1.8 billion years, when the reaction stopped what was left was the equivalent of nuclear waste. And chemical tests revealed that these deposits had remained relatively unchanged and stable for all this time. The Oklo uranium ore came to be discussed as a potential natural analog for the geological storage of nuclear waste. Or the idea that nuclear waste could be stored safely beneath the earth under certain conditions (Brookins, 1990).

This is the idea I'd like to explore in further detail in the coming weeks, as it is a complex issue, but what I think is the best chance we have at figuring out what to do with nuclear waste.

So yup just a short post today, but a slightly longer one can be expected soon!

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