Combined procedure for the determination of 90Sr, 241Am and Pu radionuclides in soil samples

A combined procedure for sequential determination of low level activity concentrations of Sr-90, Am-241 and Pu radionuclides is described. The analysis of alpha-emitters is performed by isotope dilution alpha-spectrometry using Pu-242 or Pu-236 and Am-243 tracers. Strontium-90 is analyzed by liquid scintillation counting using the double energetic windows method. The method combines the well established procedure for Pu analysis based on anion exchange, the powerful and selective method for Sr isolation based on extraction chromatography using Sr-Spec resin and finally it includes the application of the TRU-Spec column for separation and purification of the Am fraction. The radiochemical procedure was tested using IAEA reference and intercomparison materials. Major parameters of the procedure as well as advantages and drawbacks are discussed in detail.