A multi-class sedimentary dynamics modelisation to calculate the transfer of radionuclides by erosion and deposition fluxes in freshwater rivers.
O. El Ganaoui, P. Boyer, M. Amielh and F. Anselmet
Verh. Internat. Verein Limnol., 28, 1665-1668
Stuttgart, October 2002
Nuclear power plants, like any other industrial facilities, produce toxic waste. Even if the main part is in solid form and can be disposed of or re-processed (irradiated combustible, technological waste), a small part is released into the atmosphere, the sea or the rivers.
With regard to the rivers, some radionuclides are in solution, while the remainder are fixed in the suspended and in the bottom sediments. Their transfers are conditioned by the adsorption/desorption process and the mass exchange between suspended sediment and bottom sediment. These exchanges establish the sedimentary dynamics that influence the radionuclide transfers within the stream.
In a literature review, EL GANAOUI (2000) noted that radionuclides interact with cohesive sediments, which have a diameter smaller than 64 µm. Consequently, the domain of study is restrained to this clans of matter, with the sedimentary dynamics being characterized by the processes of dispersion, deposition and erosion. In this context, and for a onedimensional approach, this paper presents a model for the latter two processes (deposition and erosion), taking several classes of particles into account.