In recent years, the International Atomic Energy Agency (IAEA) has pursued innovative techniques and an integrated suite of safeguards measures to address the verification challenges posed by the front end of the nuclear fuel cycle. Among the methods currently being explored by the IAEA is automated, independent verification of the declared enrichment, 235U mass, total uranium mass and identification of declared UF6 cylinders in a facility (e.g., uranium enrichment plants and fuel fabrication plants). Under the auspices of the U.S. Support Program to the IAEA, Phase I of the Unattended Cylinder Verification Station (UCVS) project was completed in October 2016. During the Phase I final review (October 2016) and subsequent discussions, several technical questions were raised, the answers to which were important to the planning and early stages of Phase II. Under funding by the US National Nuclear Security Administration Office of International Nuclear Safeguards, Pacific Northwest National Laboratory (PNNL), Los Alamos National Laboratory, and Oak Ridge National Laboratory performed technical investigations aimed at some of these questions. PNNL led the studies regarding adaptation of gamma-spectroscopy methods to better align with the envisioned geometries of the integrated Phase II UCVS prototypes, and to improve performance for unattended enrichment verification via the 186-keV signature—particularly for cylinders at natural and depleted enrichments. This report summarizes the work performed by PNNL in these and other areas during FY17. The findings reported here have and will inform decisions about gamma-ray spectrometer type(s), module designs and analysis methods to be deployed in Phase II of the UCVS project.
Revised: October 17, 2017 |
Published: September 8, 2017