Development And Demonstration Of A Research Reactor Nuclear Security Risk Model

Nuclear security of research reactors and associated facilities (RRAFs) faces unique challenges. Although RRAFs contain nuclear and radioactive materials of varying types and activities, they often possess weaker security measures compared to larger power plant facilities. Also, the variety in RRAF types and locations makes it difficult to meaningfully compare nuclear security risks. While work has been done to estimate RRAF risks, no broad model exists that takes into account threat, vulnerability, and consequences of malicious acts to these facilities. This study adapts the Potential Facility Risk Index (PFRI) to RRAFs. The PFRI is a quantitative risk-based methodology that facilities can employ to better understand facility risk. The use of quantitative values, instead of categorical qualitative ones, allows for generation of risk values that can then be used for comparison and (cost-benefit) decision making. The computation of the Potential Facility Risk Index (PFRI) is based on the triplet definition (threat, vulnerability, and consequences) of risk. The threat component of the PFRI is devised as a utility function weighing the threat group attributes and asset preference. The principles of probabilistic risk assessment and pathway analysis are implemented to account for different attack scenarios. Locational hazards and nuclear security culture are measured as a function of facility vulnerability. The consequences of loss of life and economic loss are computed, as a result of radioactive release from an attack. In order to demonstrate the functionality of the PFRI, two security scenarios, theft and sabotage, were analyzed for the Purdue University research reactor (PUR-1). The theft of reactor fuel assemblies and the destruction of the reactor with explosives were used to estimate the probability of success by the adversary. Parameters contributing to the facility risk were analyzed along with existing vulnerabilities. Consequence calculations incorporate population demographics, local economic measures, meteorological conditions, reactor properties, and radioactive material characteristics. The contribution of the research is significant because it is the next step towards development of a new tool in the field of RRAF nuclear security-one that is expected to introduce, analyze and numerically test a methodology that yields a facility level risk index.