Nuclear archaeology to assess fissile-material inventories for nuclear safety and security, transparency, and disarmament

Uncertainties about the size of fissile-material stockpiles are large; states routinely observe differences between measured physical inventories and "book inventories." Nuclear archaeology can reduce these uncertainties. A new, integrated approach would make use of data-analysis techniques that take into account direct fissile-material measurements, a variety of forensic measurements for shut-down facilities and radioactive wastes, and fuel-cycle operational records with related simulations. This article describes that approach and includes a hypothetical case illustrating its potential to probe declared histories and detect falsifications. The article reviews past efforts to fully capture fissile-material stockpiles. Future scenarios in which methods of nuclear archaeology could be used or will be required are also discussed, including improving nuclear safety and security through better knowledge of fissile materials and radioactive waste. International exercises for transparency purposes could be carried out in either nuclear-weapon or non-nuclear-weapon states. During any disarmament process, baseline declarations of fissile materials will need to be verified to assess the potential for a warhead buildup during arsenal reductions and eventually to verify the disposal of all weapons-related fissile materials.