In large cement-based structures such as a near surface disposal facility for radioactive waste voids and cracks are inevitable. Cracks facilitate preferential water flow through the facility because their saturated hydraulic conductivity is generally higher than the conductivity of the cementitious matrix. Moreover, sorption within the crack is expected to be lower than in the matrix and hence cracks in engineered barriers can act as a bypass for radionuclides.Understanding the effects of crack characteristics on contaminant fluxes from the facility is of utmost importance in a safety assessment. In this paper we numerically studied radionuclide leaching from a crack-containing cementitious containment system. The effect of cracks on radionuclide fluxes is assessed for a single repository component which contains a radionuclide source. These analyses reveal the influence of cracks on radionuclide release from the source. The second set of calculations deals with the safety assessment results for the planned near-surface disposal facility for low-level radioactive waste in Dessel (Belgium); our focus is on the analysis of total system behaviour in regards to release of radionuclide fluxes from the facility. Simulation results are interpreted through a complementary safety indicator.We discuss the possible consequences from different scenarios ofcracks and voids.
|Title of host publication||Proceedings of the 15th International Conference on Environmental Remediation and Radioactive Waste Management - ICEM2013 (on CD)|
|Place of Publication||United States|
|State||Published - Sep 2013|
|Event||ICEM 2013 - 15th International Conference On Environmental Remediation And Radioactive Waste Management - ASME, Belgoprocess, SCK•CEN, Brussels|
Duration: 8 Sep 2013 → 12 Sep 2013
|Conference||ICEM 2013 - 15th International Conference On Environmental Remediation And Radioactive Waste Management|
|Period||2013-09-08 → 2013-09-12|