Groundwater Vulnerability Card: the Unsaturated Zone

The map of the vulnerability of the groundwater of the Flemish Region can be defined as a map of the level of risk of contamination of groundwater in the upper water layer by substances that penetrate from the soil into the ground, only taking into account static parameters. This map can later serve as a basis for a more detailed map, which can also include dynamic and hydrochemical factors. Where, however, the top recoverable aquifer is naturally silted (>>The unsaturated zone: In the absence of a coating, account is taken of the unsaturated groundwater protection zone. The thickness of the unsaturated zone is the determining factor in the classification of the unsaturated zone. There are two classes: * 10 m or less than 10 m thick; * more than 10 m thick.