A Proposed method for integrating the PNAR, TN, and CIPN techniques for the non-destructive assay of used nuclear fuel assemblies

Bolind, A.

In the first phase of its Spent Fuel Nondestructive Assay project, the Next Generation Safeguards Initiative (NGSI) of the U.S. Department of Energy (DOE) examined 14 NDA techniques for measuring the Pu and/or fissile content of used nuclear fuel assemblies, including the 3 techniques of passive neutron albedo reactivity (PNAR), total neutron counting (TN), and californium-252 interrogation with prompt neutron detection (CIPN). These 3 techniques were not integrated with each other because they all rely on the same physics of the multiplication of neutrons by fissile material. The 3 techniques also have a common problem, though. None of them can independently determine the fissile content, without additional information from either the reactor operator or some other NDA technique regarding the burnup, initial enrichment, and/or cooling time of the fuel assembly. In a recent journal article, the author has proposed a new way to integrate these 3 techniques to overcome this problem. In this INMM paper, the author will summarize this new method and describe how it can be applied to safeguards practice.