How Much is Enough?: Preliminary Insights from Search Theory as Applied to Detecting Undeclared Activities

Within its State Level Concept (SLC), the International Atomic Energy Agency (IAEA) envisions a State Level Approach (SLA) that considers, inter alia, a State’s nuclear and nuclear-related activities and capabilities as a whole when developing an annual safeguards implementation plan. An unresolved issue for the implementation of safeguards is the balance of effort amongst in-field and headquarters activities targeted at diversion, misuse, and undeclared pathways. As underestimating a State’s capabilities may lead to false negative errors and untimely detection, determining “How much is enough?” when searching for undeclared activities is essential for safeguards effectiveness and efficiency. As initial steps in this direction and to motivate further study, we qualitatively explore the theory of optimal search and stop – a mathematical approach for designing optimal search plans first developed for naval engagements and later applied to search and rescue operations – as it might be applied to the search for undeclared nuclear fuel cycle activities. Safeguards planning approaches selected from the literature are then mapped against a comparative framework inspired by search theory. Though not proposing a formal model, this mapping identifies commonalities and gaps in these approaches, and illustrates how optimal search theory might be further applied to the search for undeclared activities.