Multiactinide Analysis with Accelerator Mass Spectrometry for Ultratrace Determination in Small Samples: Application to an in Situ Radionuclide Tracer Test within the Colloid Formation and Migration Experiment at the Grimsel Test Site (Switzerland)

作者：Quinto Francesca; Blechschmidt Ingo; Perez Carmen Garcia; Geckeis Horst; Geyer Frank; Golser Robin; Huber Florian; Lagos Markus; Lanyon Bill; Plaschke Markus; Steier Peter; Schaefer Thorsten

来源：Analytical Chemistry, 2017, 89(13): 7182-7189.

DOI：10.1021/acs.analchem.7b01359

The multiactinide analysis with accelerator mass spectrometry (AMS) was applied to samples collected from the run 13-05 of the Colloid Formation and Migration (CFM) experiment at the Grimsel Test Site (GTS). In this in situ radionuclide tracer test, the environmental behavior of U-233, Np-237, Pu-242, and Am-243 was investigated in a water conductive shear zone under conditions relevant for a nuclear waste repository in crystalline rock. The concentration of the actinides in the GTS groundwater was determined with AMS over 6 orders of magnitude from similar to 15 pg/g down to similar to 25 ag/g. Levels above 10 fg/g were investigated with both sector field inductively coupled plasma mass spectrometry (SF-ICPMS) and AMS. Agreement within a relative uncertainty of 50% was found for Np-237, Pu-242, and Am-243 concentrations determined with the two analytical methods. With the extreme sensitivity of AMS, the long-term release and retention of the actinides was investigated over 8 months in the tailing of the breakthrough curve of run 13-05 as well as in samples collected up to 22 months after. Furthermore, the evidence of masses 241 and 244 u in the CFM samples most probably representing Am-241 and Pu-244 employed in a previous tracer test demonstrated the analytical capability of AMS for in situ studies lasting more than a decade.

• 出版日期2017-7-4