The heat and radioactivity are generated by the decay of new radioactive materials produced during nuclear power production. Following discharge from the reactor, the spent fuel must be stored securely, usually under water, to allow it to cool. There are two alternative routes for spent fuel management over the longer term. Justifications for reprocessing To tell the story of how civilian reprocessing has evolved it is necessary to know not only about the technological and industrial context, but also about the assumptions and beliefs which have powered the whole enterprise. Nuclear reprocessing is the quintessential 'big' technology.
Big technologies require strong rationales.
Over time, as conditions and perceptions change, these rationales are also forced to change. Justifications for civilian reprocessing fall roughly into three time periods. During the early period stretching from the 1960s to the mid-1970s, reprocessing was considered the only viable management option for most spent fuel types. Recycling plutonium in this way would unlock the energy potential of the more abundant uranium-238 which does not fission in significant amount in conventional reactors. Nuclear power grew more slowly than expected and uranium, far from being scarce, turned out to be relatively abundant.