Assessment of resuspend bottom material into the water column during the possible removal of dumped ammunition from the sea.

Ammunition dumped in the sea generates specific problems related to decision making about what will happen in the event of a leak and the consequences when it will be taken out of the sea. One of the reasons for the difficulties in making decisions is the lack of knowledge about the dumped material (it may be, for example, chemical munitions), the level of pollution in the surrounding area, and the mobility of the sediments in which it was found. Therefore, the main goal of this work is to develop a model that will be an element of the system providing information on the mobility of sediments and thus the possibility of spreading the contaminated fraction. The whole will consist of several elements, including a demonstrator for analysing the properties of sediments. An important element is to get the real value of the threshold shear stress to calculate the current speed required to resuspend individual particles or upper sediment layers. Additionally, the properties of the sediment will be determined on the basis of the in situ collected samples. All this will allow the development of a model providing information on the mobility of bottom material introduced into the sea depths and, consequently, the contaminated area. The work concerns preliminary activities, and the concept of the system along with preliminary results will be presented. At this stage, the shear stress threshold measurement also requires tuning. It is important to add that this is to be part of a larger system to support the selection of the most appropriate approach when ammunition is found in the Baltic Sea.

 

The results are part of the EU MARTERA project PROBANNT. Study partially financed by the National Centre for Research and Development, Poland