Infuence of liquid/solid ratios in radionuclide migration studies

An application of distribution coefficients in transport models must take into account, among others, influences of solution-to-solid (V/M) ratios. Therefore, with batch tests the dependence of sorption and desorption coefficients on V/M in rock-groundwater systems of the Gorleben site was investigated. Experiments show that sorption (R_S) and desorption (R_D) coefficients of Ra, U, Pa and Ac decrease with decreasing liquid/solid ratios. In order to understand the V/M-effect sorption isotherms for different V/M ratios and, moreover, quantities for characterizing specific sorption of nuclides have been measured. The results allow the postulation of a model for describing approximately R_S-V/M-relationships of different nuclide/rock/groundwater system with specific parameters.Paper presented at International Conference on Nuclear and Radiochemistry, Lindau, October 8–12, 1984, FRG