A report just made public by the U.S. Department of Energy confirmss that it’s not only weapon-grade plutonium that can be used for a nuclear device.
The report by Los Alamos National Lab and dated March 31, 2021, is titled “Commonly Overlooked Material Attractiveness Issues” and the summary confirms what we have long known, that reactor-grade plutonium (such as from reprocessing of commercial spent fuel) is weapon usable. But other materials are also weapon usable.
Report is linked here: https://permalink.lanl.gov/object/tr?what=info:lanl-repo/lareport/LA-UR-21-23091
The report states that “The IAEA and US DOE definitions of an SQ [Significant Quantity] of Pu are 8 and 4 kg, respectively, because each organization makes different assumptions about their adversary.” An SQ is a minimum amount of material needed for a nuclear weapon. The 8 SQ figure of the International Atomic Energy Agency is what is commonly used so interesting to see the DOE SQ number here. (In case DOE takes the report down, we’ve posted it here: Commonly Overlooked Material Attractiveness Issues LANL March 31 2021.)
Summary
SG-Pu, WG-Pu, FG-Pu, RG-Pu, HEU, and Np should
not be ignored in safeguards or security discussions:
– Nation states prefer SG-Pu and WG-Pu for missile delivery
– Terrorists and some nation states will prefer FG-Pu and
RG-Pu to minimize the mass that must be stolen/diverted
and to minimize the risk of detection
– Terrorists and some nation states will prefer HEU to
eliminate the need for testing
– A nation state with reprocessing capabilities might prefer
237Np because the IAEA doesn’t require it to be
safeguarded
– Terrorists might prefer 237Np if the nation state does not
provide adequate safeguards and security for it
Report linked here: https://permalink.lanl.gov/object/tr?what=info:lanl-repo/lareport/LA-UR-21-23091