Impact of Heterogeneity on Gamma-Spectrometry Data at Nondestructive Assay of Radioactive Waste

Abstract

The uncertainty of the direct gamma-spectrometry method at a nondestructive assay of radioactive wastes is considered by taking into account the heterogeneity (over the container’s volume) of the activity and of the gamma-attenuation factor distributions. Since it is impossible to obtain in a real assay the estimations of the uncertainty in individual cases, the “maximal uncertainty” approach to characterize the method is introduced in this study. It is shown that the relative maximal uncertainty of the assay is comparatively small in a rather wide range of container’s volume values (at least for bulk volumes up to