Title: Expanding our understanding of nuclear forensic signatures
in Advanced Reactor Fuels
Authors: Ruth Kips1, Naomi Marks1
1Lawrence Livermore National Laboratory, Livermore, CA
Abstract: Nuclear security aims to prevent, detect, and respond to malicious acts involving nuclear material. Nuclear forensics is a key element of nuclear security and traditionally has leveraged known relationships between material characteristics and process history to establish material provenance. A major goal in recent years has been to increase the confidence in nuclear forensics signatures in order to better understand the influence of process history on sample characteristics. The surge in development of Advanced and Small Modular Reactors poses some new and unique challenges for nuclear forensics.
Specifically, many of the Advanced Reactors (ARs) under development will use fuels that differ in important ways from fuels common today (e.g., tri-structural isotropic (TRISO) fuel forms, molten salts). Additionally, Small Modular Reactors (SMRs), or microreactors, will be small enough to fit on a semi-truck that can be deployed to remote locations and military bases as a reliable source of heat and power. As a result, the nuclar materials in these reactors may be at even greater risk of diversion or improper use. Because of these distinctly different deployment scenarios and novel fuel types, AR/SMRs pose specific challenges to nuclear non-proliferation and nuclear security, including our ability to detect, deter and investigate nuclear materials that fall out of regulatory control.
In order to sustain and strengthen our capability to effectively determine the origin and process history of smuggled/interdicted fuel cycle materials, we need to develop a better understanding of the characteristics and signatures of these materials that will permit the assessment of material provenance. TRISO-based fuel forms offer particular opportunities for capability development, as there has been significant research and development of these fuel forms, and they pose some specific challenges for forensics analysis.
This work aims to provide an overview of our current nuclear forensics capabilities for nuclear fuel cycle materials, while examining opportunities for research and development with respect to the nuclear forensic analysis and interpretation of pebble bed/TRISO fuel, as well as other advanced fuel types.