1. Researcher, Geological Survey of Norway (NGU), Postboks 6315 Sluppen, 7491 Trondheim, Norway (corresponding author).
2. Head of Department, Norwegian Water Resources and Energy Directorate, Postboks 5091 Majorstua, 0301 Oslo, Norway.
3. Professor, Geological Survey of Norway (NGU), Postboks 6315 Sluppen, 7491 Trondheim, Norway.
4. Researcher Engineering, Norwegian Water Resources and Energy Directorate, Postboks 5091 Majorstua, 0301 Oslo, Norway.