Historical Investigation and Risk Mitigation for the Identification of Unexploded Ordnance (UXO) in the North Sea and Baltic Sea

In the European Waters there is still a huge amount of Unexploded Ordnance (UXO) in place. Different causation scenarios from war hostilities and military actions have led to an unknown amount of different UXO in the Baltic Sea, as well as in the North Sea. Sediment movement, currents or missing information make it difficult to determine the exact position or the amount of remaining UXO with geophysical methods. Since the upcoming and growing economic use of the Baltic Sea (windfarms, pipelines, cables), an extensive Risk Mitigation and the development of working procedures are becoming more and more inevitable. There are well established procedures to perform a historical investigation for hazard identification on land. This stepwise procedure is defined in a German working guide on explosive ordnance clearance. It is transferred to be used in German waters and can also be used for other countries around the Baltic Sea. The historical investigation prepares a geophysical investigation previously to offshore construction work and will reduce the costs and minimize the risk for personnel, equipment and the environment.