1. The Hydrogeophysics Group, Department of Earth Sciences, University of Aarhus, Høegh-Guldbergs Gade 2, DK-8000 Aarhus C, Denmark.
2. Corresponding author.
3. Geological Survey of Denmark and Greenland – GEUS, Department of Groundwater Mapping, Lyseng Alle 1, DK-8270, Højbjerg, Denmark.
4. Orbicon A/S, Department of Water Resources and Applied Geophysics, Jens Juuls Vej 16, DK-8260, Viby J, Denmark.
5. Aarhus Geophysics, Høegh-Guldbergs Gade 2, DK-8000 Aarhus C, Denmark.