Review of sorption values for the cementitious near field of a near-surface radioactive waste disposal facility

This paper reports part of the documentation being assembled by ONDRAF/NIRAS to support the safety assessment of the near-surface disposal of short-lived low and intermediate level waste (LILW-SL) or category A waste at Dessel, Belgium. The aim of this study was to establish a sorption database of critical radionuclides and chemotoxic elements on concrete through literature review and data selection with the support of an international panel of experts (for details see Wang et al., 2009). The database compiles sorption values in the form of distribution coefficients (Kd values) or distribution ratios (Rd values) for radionuclides sorption on cementitious materials. The database is to be used in safety assessment calculations to quantify the retardation of safety relevant radionuclides in the cementitious near field. Sorption values were critically reviewed and selected for both reducing and oxidizing conditions. Therefore, the resulting sorption values are also applicable to geological disposal studies. To support the evaluation of sorption values, solubility of concerned elements was also discussed.