Solubility of radionuclides in Supercontainer concrete. Transferability document: Use of solubility determined within the category A (cAt) project in the B&C waste disposal assessment.

This report provides the near-field solubility values of 25 radionuclides identified as relevant by safety assessment on the disposal of Belgian B&C radioactive wastes in Boom Clay as the repository host formation. Because of the use of concrete as construction and backfill materials, the geochemical condition of the near-field is controlled by interaction of clay pore fluids with cement materials. Majority solubility values are calculated using a geochemical computer code and a thermodynamic data while other values are based on experimental data from literature. Wherever available, values determined in a previous work performed for a near-surface disposal of Belgian category A waste are adapted.