Natural analogue study for low-and-intermediate level radioactive waste shallow burial disposal

The paper makes a comparison of low-and-intermediate level radioactive waste shallow burial disposal with Chinese ancient tombs in respects of siting, engineering structures, design principle and construction procedures. Results showed that Chinese ancient tombs are very good analogue for low-and-intermediate level radioactive waste shallow burial disposal. Long-term preservation of ancient tombs and buried objects demonstrated that low-and-intermediate level radioactive waste shallow burial disposal would be safe if suitable sites were selected, reasonable engineering structures and good backfill materials were adopted, and scientific construction procedures were followed. The paper reports for the first time the testing results of certain ancient tomb backfill materials. The results indicated that the materials have so low a permeability as 1.5 x 10-8 cm/s , and strong adsorption to radionuclides Co and Cs with the distribution coefficients of 1.4 x 104 mL/g and 2.1 x 104 mL/g, and the retardation factors of 4.4 x 104 and 7.7 x 104 respectively. Good performance of these materials is important assurance of long-term preservation of the ancient tombs. These materials may be considered to be used as backfill materials in low-and-intermediate level radioactive shallow burial disposal. (4 figs., 10 tabs.)