Additional protection could be obtained using a variant of the UREX+ process that mixed certain radioactive fission products
in with the plutonium and the minor actinides.
Calculations conducted at Oak Ridge National Laboratory showed that georeactor fission products
would include helium in precisely the range of compositions observed exiting Earth in volcanic lava.
Even though the plant is now shut down, fission products
such as uranium continue to generate heat, and therefore require cooling.
A modest fraction of radioactivity comes from fission products
that remain radioactive for decades, and a very small fraction from radioactive isotopes--primarily heavy elements such as plutonium created by neutron capture, as well as some of their radioactive decay products--that persist for tens to hundreds of millennia.
131]I), an isotope present in nuclear fission products
I participated in studies at Battelle in the 1970's that showed that the fuel can be reprocessed in such a way that the vast majority of the long-lived fission products
, including the transuranic materials, such as plutonium, can be recycled and successfully used as a new reactor fuel material.
Because the fragments move at nearly the uranium beam's velocity and because they are totally stripped of electrons, "the fission products
are much easier to detect than in previous experiments," Bernas explains.
Development of Glass Compositions to Immobilize Alkali, Alkaline Earth, Lanthanide and Transition Metal Fission Products
from Nuclear Fuel Reprocessing
Objective: In case of a severe accident in a Nuclear Power Plant (NPP) fission products
are released from the degraded fuel and might reach the environment if their confinement is lost and/or bypassed.