Comment Re:Energy Independence (Score 1) 438
Yes, the radioactivity near coal plants is higher than near nuclear plants due to the radioactive isotopes of carbon as well as differrent contaminations in the coal. Although this is almost negligible in comparison to the dose you get from medical examinations for example.
Most nuclear waste is _not_ usable in other reactors, i.e. the fission products are itself radioactive, yes, but not fissile. For a powerplant you can't just throw in any radioactive material, only few are able to sustain a chain reaction.
Breeding reactors do not use the fission products. The pellets contain non-fissile material like U238 which is transformed by the neutrons into fissile material. If this is fissioned you have to replace it, too. Anyway, breeders are not really used today due to other potential security issues (e.g. liquid sodium), about a handful worldwide.
Even modern reactor types can go critical, there is no absolute safety if you rely on a chain reaction. You can only design the core such that a meltdown is highly improbable. Therefore most reactors have a ceramic basin underneath the core which is especially built to catch it in case it melts.
Most nuclear waste is _not_ usable in other reactors, i.e. the fission products are itself radioactive, yes, but not fissile. For a powerplant you can't just throw in any radioactive material, only few are able to sustain a chain reaction.
Breeding reactors do not use the fission products. The pellets contain non-fissile material like U238 which is transformed by the neutrons into fissile material. If this is fissioned you have to replace it, too. Anyway, breeders are not really used today due to other potential security issues (e.g. liquid sodium), about a handful worldwide.
Even modern reactor types can go critical, there is no absolute safety if you rely on a chain reaction. You can only design the core such that a meltdown is highly improbable. Therefore most reactors have a ceramic basin underneath the core which is especially built to catch it in case it melts.