Joint application of high-resolution seismic and GPR measurements to monitor sludge deposition: Advances of the geowaters project

New sediment layers accumulating on the floors of rivers, canals, lakes, and harbours in industrialised countries contain varying amounts of contarninants, which have been discharged from a range of activities, both legal and illegal. These contaminated sediments are known collectively as sludge and have been accumulating for decades. The identification of contamination in waterways has led to the realisation that there is a need to carry out surveys of the pollution, in many cases followed by remediation. Contaminated water floors, though probably created in the past, continue to disperse their pollutants in the water, thus creating a potential effect on the quality of drinking water and recreational water. Remediation work can only be carried out in a cost effective way if it is preceded by a site survey, which provides high resolution data. 95% of current site surveys are done by collecting hand drilled cores for examination and analysis. These point sources of data are then used to try to give an impression of the sludge layers, but the resolution is extremely poor. Contamination may be found, but the volumes cannot be exactly quantified.