Soil is a finite and complex resource and understanding it is a challenge for us all. The soil is constantly changing and has a significant impact when this is studied in real cases because the soil is live and is not an inert system! As consequence, due to the complexity of real soil behaviour it is not possible to cover a detailed understanding of the characterization of pollutants at the site-scale. In view of that, Natalia Fernandez from University of Liège, in order to overcome such difficulties in soil and groundwater pollutant characterization, has set up a field experiment to investigate the fate and transport of pollutants from vadose zone and across groundwater at a former industrial site in Belgium. It is interesting underlining what a vadose zone is exactly, extending from the terrestrial surface to the top of the groundwater.
As a result of the legacy of the activities on site there is significant contamination by pollutants such as cyanide, CN− (cyanides are used widely and extensively in the manufacture of synthetic fabrics and plastics, metal mining operations, as pesticides and intermediates in agricultural chemical production) BTEX, Benzene, Toluene, Ethylbenzene and the Xylene isomers (are coming from industrial activities, traffic emission), PAHs, polycyclic aromatic hydrocarbons (are mainly derived from anthropogenic activities related to pyrolysis and incomplete combustion of organic matter) and heavy metals in soil and groundwater that are giving rise an impact of indirect manner on our health.
The new system will attempt to give us the keys to obtain a detailed understanding of the characterization of pollutants at the site‐scale and their fate and transport in the soil‐groundwater. As Natalia says “The combined experiment will consist of a tracer test performed directly in the vadose zone via infiltration rings, located within an infiltration pond. Two inclined boreholes will be drilled below the infiltration pond, both containing a vadose monitoring system (VMS). Additionally, this system will comprise different elements, among which are the vadose sampling ports and flexible time domain reflectometry probes (FTDR). Sampling ports will be used for sampling pore water in the vadose zone, whereas the FTDR probes measure water content. As well, these measurements will be used for determining solute fluxes. Finally, additional boreholes will be installed in the unsaturated zone to conduct cross-hole geophysics with the aim of monitoring contaminants and tracers as they move into the saturated zone”.
Natalia and the group which is involved, will proceed with the installation of the Vadose Monitoring System (VMS) during the first week of June (3-7 June) in Belgium. As it advances, we will able to explain with more detail the system with videos and photos and obviously the results that will be of great interest.
- Impacts of soil – aquifer heat and water fluxes on simulated global climate (gsoil.wordpress.com)
- Soil Remediation Technologies (sjclement.wordpress.com)