Cement solidification of soil and interactions between cement and radioactive contaminated soil

Radioactive contaminated soil may sometimes have to be handled as radioactive waste. The feasibility of cement solidification of soil contaminated with Cs and Sr radioisotopes was investigated. Hardening retardation can be overcome by use of a special additive, but the method is not reliable for all soils. Retention of Cs and Sr was less good in the cemented soil than in untreated soil. Improved Sr retention was achieved after reaction with carbon dioxide from the environment. The containment of the two radioisotopes in soil by barriers of soil, cemented soil or cement mortar was also investigated. Concrete is a better barrier for Sr than soil. For Cs there can be somewhat higher transport in or in contact with cementitious materials, but the difference is not of practical significance. (au) (12 tabs., 29 ills., 21 refs.)