Immobilization of Cs-137 in concrete

To assess the safety for disposal of radioactive waste-cement-bentonite composition, the leaching of Cs-137 from a waste composite into a surrounding fluid has been studied. Leaching tests were carried out in accordance with a method recommended by IAEA. Determination of retardation factors, K-F and coefficients of distribution, k(d), using a simplified mathematical model for analyzing the migration of radionuclides, has been developed. Results presented in this paper are examples of results obtained in a 10 year mortar and concrete testing project, which will influence the design of the engineered trenches system for a future central radioactive waste disposal center