Combining Multi-compartment Sampler and Geophysical Techniques for Monitoring Contaminant Transport in Soils, 2016

Pollution of soils is a widespread problem and is an important part of the still to be implemented Soil Directive (EU). Solute transport is strongly affected by heterogeneity. This effect needs to be understood to improve risk assessment, monitoring, and treatment strategies for natural attenuation in an optimal way both environmentally and cost effectively. “Combining Multi-compartment Sampler and Geophysical Techniques for Monitoring Contaminant Transport in Soils, 2016” aimed at developing integrated technologies and modelling tools for soil contamination assessment and site characterisation at the scale of management decisions (field scale). Multi-compartment samplers (MCS) measure downward fluxes with high spatio-temporal resolution and show the effect of subsurface heterogeneities. At the field scale, geophysical techniques have become more widespread to monitor hydrogeological processes. These techniques are promising regarding cost efficiency and spatial versatility, but require ground truth. Geophysical time-lapse measurements in combination with novel ground truth methods (like MCS) give the possibility to determine absolute contamination levels, spatial spreading. Better monitoring of contaminant behavior is a prerequisite for improved measures and reduced concentrations of contaminants. Never before has the high spatio-temporal resolution data of contaminant transport provided by the MCS at field scale been combined with different geophysical methods. In this project the MCS was modified to meet the needs for more flexible use and was combined with 2D geophysical techniques. The MCS was equipped with instrumentation for geophysical measurements, and MCS water samples provided ground truth for the geophysical methods. In the proposal of this project it was put forward that innovative integration of MCS and geophysical techniques, and modelling, would be used to improve our process understanding of contaminant transport and for optimising monitoring strategy. This integration of techniques and tools would then be used to develop instruments for better decision making by the stakeholders.