Abstract

This report presents the results of the RIVM study for the INTRAVAL testcase WIPP. This testcase is based on experiments carried out in the rocksalt formation in the underground facility near Carlsbad, New Mexico, USA. Some of these experiments study the movement of brine in rocksalt under prevailing underground conditions and as a result of an increase in temperature. In brine inflow experiments, the inflow of brine in an open well is measured as a function of time. In pressure build-up experiments, wells with a radius of 10 cm are filled with brine and sealed. The pressure in the brine will than increase as a function of time due to the inflow of brine. This pressure is measured in compartments of the borehole which are sealed by packers. The computer code METROPOL-2 has been used to simulate these experiments. Results of these calculations are compared with the measurements. From the results it can be concluded that the movement of brine in rock salt under the influence of pressure gradients can be described by Darcy's law. However, changes of hydrological parameters such as permeability and porosity of the rock salt due to deformation of the rock salt requires the coupling of a flow model with a rock mechanical model.