MODELING OF POTENTIAL EFFECTS OF LONG-TERM FLUVIAL DYNAMICS ON POSSIBLE GEOLOGICAL STORAGE FACILITIES OF NUCLEAR WASTE IN THE NETHERLANDS

Within the programme of investigation for suitable safe geological sit es (such as salt diapirs) for long-term storage of radioactive waste ( OPLA), a modelling study of long-term effects of fluvial dynamics was carried out. The model used, FLUVER, allows long-term simulations of t he combined effects of climatic change, tectonism, sea level and initi al relief on fluvial erosion. As an exercise, landscape development sc enarios of a Rhine-Meuse type system with climate and base-level dynam ics related to Milankovitch's astronomical theory, during stable, upli fting, and subsiding tectonic scenarios, are simulated and discussed. Under the assumptions that climate and base-level changes can be descr ibed with Milankovitch's theory and that tectonic activity in the Neth erlands will not change considerably during the next hundred thousands of years, it can be concluded provisionally that the maximum fluvial erosion depth in the next few hundred thousand years is unlikely to ex ceed 100 metres and to reach a salt diapir.