Safety analysis of nuclear installations involves the study of scenarios related to the release of radionuclides in the environment and their subsequent transport to a critical group of population. If transport in air and water is solved by the knowledge of few parameters easily measurable, groundwater transport is more complicated for the difﬁculty in measuring or ﬁnding the parameters involved in bibliography. At the current state of the art, groundwater calculations are usually performed by software platforms such as FRAMES 1.6. Correct utilization of FRAMES 1.6 as regards groundwater involves the knowledge of parameters such as soil absorption coefﬁcients, bulk density, soil class and Darcy velocity. The latter is one of the most important parameter for simulation. It depends on permeability, dynamic viscosity and porosity of the soil. This work presents a parametric analysis on the inﬂuence of Darcy velocity for a case of radioactivity release in groundwater. The study is intended to give the safety analyst an instrument to device ﬁgures, for instance minimum–maximum approximations, on radionuclide transport in groundwater.
aquifer, Darcy velocity, groundwater, radioactive contaminant, safety analysis, vadose zone.
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