Thursday 1 October, 4 PM CET
ABSTRACT: The Orano Tricastin industrial platform, located in the south of France, encompasses several chemical processes and uranium enrichment activities. In order to assess the potential environmental impact of these activities, an extensive monitoring program is performed by Orano at the Tricastine site. Special emphasis is placed on the analysis of uranium content in water because the site is located on the right bank of the Channel of Donzère-Mondragon and the Gaffière river passes directly through the Tricastin site. Moreover, a large number of piezometers were installed on and around the site so that the uranium concentration can also be monitored in groundwater. Over one thousand samples in total are analyzed per year directly on-site within this monitoring program. Therefore, there was an idea to use a passive sampling method in order to reduce the number of samples and analyses that need to be processed in the laboratories on site. Thus, the suitability of diffusive gradients in thin films (DGT) technique for long-term monitoring of uranium in groundwater and surface water was tested. Nevertheless, the preliminary expedition revealed that commonly used DGTs provides unsatisfactory results in calcium bicarbonate rich waters of the Tricastin site even after very short deployment periods (2 days). Therefore, extensive laboratory testing has been performed in order to find the most effective DGT design for long-term monitoring of uranium which would reliably provide the time-integrated averaged U concentration in surface water and groundwater.