Editing Radioactive waste (section)

=== Nuclear weapons decommissioning ===
Waste from nuclear weapons decommissioning is unlikely to contain much beta or gamma activity other than [[tritium]] and [[americium]]. It is more likely to contain alpha-emitting actinides such as Pu-239 which is a fissile material used in nuclear bombs, plus some material with much higher specific activities, such as Pu-238 or Po.

In the past the neutron trigger for an [[atomic bomb]] tended to be [[beryllium]] and a high activity alpha emitter such as [[polonium]]; an alternative to polonium is [[Pu-238]]. For reasons of national security, details of the design of modern nuclear bombs are normally not released to the open literature.

Some designs might contain a [[radioisotope thermoelectric generator]] using Pu-238 to provide a long-lasting source of electrical power for the electronics in the device.

It is likely that the fissile material of an old nuclear bomb, which is due for refitting, will contain decay products of the plutonium isotopes used in it. These are likely to include [[U-236]] from Pu-240 impurities plus some U-235 from decay of the Pu-239; due to the relatively long half-life of these Pu isotopes, these wastes from radioactive decay of bomb core material would be very small, and in any case, far less dangerous (even in terms of simple radioactivity) than the Pu-239 itself.

The beta decay of [[Pu-241]] forms [[Am-241]]; the in-growth of americium is likely to be a greater problem than the decay of Pu-239 and Pu-240 as the americium is a gamma emitter (increasing external-exposure to workers) and is an alpha emitter which can cause the generation of [[heat]]. The plutonium could be separated from the americium by several different processes; these would include [[Nuclear reprocessing#Pyroprocessing|pyrochemical]] processes and aqueous/organic [[solvent extraction]]. A truncated [[PUREX]] type extraction process would be one possible method of making the separation. Naturally occurring uranium is not fissile because it contains 99.3% of U-238 and only 0.7% of U-235.