AMS measurement of I-129, Cl-36 and C-14 in underground waters from Mururoa and Fangataufa atolls

AMS analyses of Cl-36, I-129 and C-14 in underground water have been perfor med as part of IAEA's assessment of the radiological situation at Mururoa a nd Fangataufa atolls. The samples consisted of waters from monitoring wells , and from two cavity-chimneys created by underground nuclear tests. The wa ter samples from the monitoring wells contained varying concentrations of r adionuclides, with the highest concentrations of radionuclides found in the two test cavity-chimneys. A comparison of the concentrations of radionucli des determined by AMS, Cl-36 and I-129, and with radionuclides determined u sing conventional methods, H-3, Sr-90 and Cs-137, shows a reasonable correl ation. However, some differences in behaviour, mainly attributed to differe nces in the sorption characteristics of the elements, are discernible. The concentrations of radionuclides in the underground environment were used to validate geosphere transport models. (C) 2000 Elsevier Science B.V. All ri ghts reserved.