Accurate determination of Ca-41 concentrations in spent resins from the nuclear industry by Accelerator Mass Spectrometry

The radiological characterisation of nuclear waste is essential for managing storage sites. Determining the concentration of Long-Lived RadioNuclides (LLRN) is fundamental for their long-term management. This paper focuses on the measurement of low Ca-41 concentrations in ions exchange resins used for primary fluid purification. in Pressurised Water Reactors (PWR). Ca-41 concentrations were successfully measured by Accelerator Mass Spectrometry (AMS) after the acid digestion of resin samples, followed by radioactive decontamination and isobaric suppression through successive hydroxide, carbonate, nitrate and final CaF2 precipitations. Measured Ca-41 concentrations ranged from 0.02 to 0.03 ng/g, i.e. from 0.06 to 0.09 Bq/g. The Ca-41/Co-60 activity ratios obtained were remarkably reproducible and in good agreement with the current ratio used for resins management. (C) 2013 Elsevier Ltd. All rights reserved.