Improving the Precision of Nuclear Material Quantification in Large Vessels

While safeguards by design is now a standard practice for new facilities, Canada’s nuclear industry includes large facilities at the front-end of the fuel cycle with very large throughputs which predate modern safeguards. This paper describes processes and considerations that need to be taken into account in performing a Physical Inventory Taking in such plants. The CNSC leveraged the Canadian Safeguards Support Program to launch two separate projects to develop techniques to more accurately determine the volume, as well as the density, of in-process powders, in order to determine more precisely the mass of the nuclear material. This paper considers the use of 3D laser scanning technology for volume determination and investigates some of the effects of density variations within a vessel.