To access the long-term safety of radioactive waste disposal systems, validation of predictive models is essential and large efforts should be given to barriers, particularly geologic barriers. This work appears in the form of four volumes, the subject of the third part is described below. This work shows the compacting effects on a sedimentary serie and the consequences on fluid flows in water-table with an ice-cape progressive arrival. The fast advance of the glacier prevents from the entire sedimentary beds consolidation and it appears a horizontal fluid flow along the progression axis. The computerized simulation uses GEFDYN code, a finite elements code. 27 figs., 12 refs..