One reason is that this enables plutonium to be separated out, and so gives the opportunity to make fission bombs. If the spent fuel is stored whole then this cannot happen. Apart from this, reprocessing is a messy chemical process with many chances of radioactive arisings being leaked to the environment-we have seen this at Sellafield in the UK.
Nuclear Reprocessing
1977
The source of plutonium is the reprocessing of "burned" nuclear reactors fuels.
The source of technetium in the environment are nuclear fuels reprocessing plants.
By reprocessing spent fuel plutonium can be obtained, this can be added to uranium to make a mixed oxide fuel (MOX), so it is a form of recycling, though it is not the original U-235 that is recycled.
It can produce low grade plutonium that need be extracted from the used nuclear fuel through used fuel reprocessing. However, power reactors are subject to the international nuclear safeguards to prevent its misuse.
Plutonium is found in the nature only as ultra-traces accompanying uranium minerals. Plutonium is obtained in industrial quantities in the nuclear reactors technology, by reprocessing of the burned nuclear fuels.
Sellafield is located close to the village of Seascale. It can be found close to the coast in the Irish Sea. It is in England in the county of Cumbria.
Gordon R. Thompson has written: 'Evidence to the Windscale Inquiry on the safety assessment of nuclear fuel reprocessing, storage and ancillary activities' -- subject(s): British Nuclear Fuels, British Nuclear Fuels. Windscale and Calder Works
nuclear is good and bad at the same time.
there are no bad things about the nuclear power reactors
The prncipal nuclear reaction to obtain americium is: 239Pu---------(n,γ)------ 240Pu---------(n,γ)------ 241Pu ---------(β-)------241Am Americium is a by-product of nuclear fuels burn-up and can be extracted (with many difficulties and costs) from these irradiated fuels in reprocessing plants.