Examining Reprocessing Waste to Help Estimate Past Plutonium Production

Nuclear archaeology techniques are being developed to verify the completenessof declarations of initial fissile material holdings. Such a capability is important in thenon-proliferation context when a state with past nuclear activities joins the Non-ProliferationTreaty, and in the arms control and disarmament contexts, if states declare their existing fissilematerial inventories. In cases where permanent structural or moderator materials existinside a reactor core and are accessible to inspectors, forensic analysis of according samplescould be useful to estimate plutonium production. As this may not always be the case, alternativesare required. This paper presents initial results of an examination to which extentmeasuring reprocessing waste can help verify declarations. In certain cases, it may serve eitheras a stand-alone capability, where other nuclear archaeology measures are not possible, or as acomplementary consistency-check to increase confidence in the completeness of declarations.To assess the capabilities, we define several specific reactor operation histories, and simulatethe fuel depletion, the separation process, and the decay of spent fuel and waste.