Uncertainty in the reactive transport model response to analkaline perturbation in a clay formation

摘要: The mineral alteration in the concrete barrier and clay formation around long-lived intermediate-level radioactive waste French deep geological disposal concept is evaluated using numerical modeling. There are concerns that mineralogical composition of surrounded will not be stable under high alkaline pore fluid conditions caused by (pH {approx} 12). Conversely, infiltration CO{sub 2}-rich groundwater from into initially unsaturated concrete, at temperature (T 70 C) produced decay radionuclides, could cause carbonation, thereby potentially affecting critical performance functions this barrier. This also lead to significant changes porosity, which would affect aqueous diffusive transport radionuclides. All these processes therefore intimately coupled advanced reactive models required for long-term assessment. uncertainty predictions one major question must answered. A mass-transfer model response an perturbation with standard values first simulated two-phase non-isothermal code TOUGHREACT. selection input parameters thereafter designed sample uncertainties a wide range physico-chemical without making priori assumptions about relative importance different feedbacks. 'base-case' simulation perturbed setting parameter minimum, intermediate or maximum value switching on/off process. sensitivity analysis conducted grid computing facilities BRGM (http://iggi.imag.fr). Our evaluation preliminary results suggests resaturation heating near-field long enough duration limited carbonation through all width Another prediction possibility self-sealing concrete/clay interface. Further research however discuss effect such evolution on desirable function both barriers.