SUBSEABED DISPOSAL OF RADIOACTIVE-WASTE - EFFECTS OF CONSOLIDATIONAL FLUID-FLOW

Subseabed disposal of radioactive waste applies a multiple-barrier con cept with the sediment being the most important barrier for preventing a release of nuclides into the biosphere. While many investigations h ave been carried out to analyze the risk potential in this type of dis posal, the effects of sediment consolidation and associated fluid flow have not fully been taken into consideration. Here, possible effects of consolidational fluid flow in the penetrator disposal option and po ssible consequences to the transport of nuclides in the sediment are a nalyzed. Results of numerical experiments demonstrate that consolidati on contributes to the transport of radioactive nuclides released from containers buried in the sediment and to the release of nuclides at th e sediment-water interface. Both depend on geological conditions and t o a large extent on possible alterations of hydraulic conductivity of the sediment in the vicinity of the entry path of a penetrator.