Drilling work that goes so deep into the ground that it can affect the movement or composition of the groundwater is referred to as "ground excavation". If you are planning such an exploration for geothermal use with a vertical geothermal probe, you must apply to the relevant water authority.

Each borehole provides data for the evaluation of the subsurface at the respective location. The notification enables the responsible authorities to gain an impression of the drilling project and the drilling material produced on site. The authorities can take additional measurements and ensure the quality of the drilling results. This prevents costly mistakes in underground spatial planning.