Bore hole sounding in practice
Due to their high kinetic energy at the moment of Impact dud bombs come to rest deep down in the subsoil most of the time. Depending on the soil’s structure and conditions on the surface these relics of aerial warfare may penetrate the soil down to depths of 6 meters [18 ft] and come to rest far away from their point of Impact. Metallic objects burrowed in the ground are a source of Interference making detection from the surface often difficult or not safe enough to allow the precise localization and a complete disposal.
The bore-hole sounding method is the way to achieve complete results here. From the Interpretation of aerial photography made available by the authorities of the federal state, suspected sites are identified and superimposed by a grid. The grid covering such sites as craters caused by dud bombs is then sounded out. At regular Intervals perpendicular sounding holes are then drilled 6 meters [18 ft] deep allowing the soundings to be carried out.
Prior to the deep sounding, a surface sounding is carried out. That is followed up with drilling field holes, which are subjected to a step-by-step preliminary soundings of suspected sites. Next, plastic tubes are inserted to prevent the holes from silting up. The actual depth sounding begins with the lowering of the probe sensor (Magnetic-field radiometer) and a controlled and steady measurement over the entire depth of the hole. The results are recorded on the data logger and as a rule they are evaluated on-site in our mobile data station.
Through a systematic Investigation of the area a complete grid is generated allowing the Identification and removal of unexploded bombs and other relics of war. This extensive method also protects people from incalculable risks and saves the environment from the consequences of contamination.