Ran, A, Pérez, N & Dahan, O 2020, 'Real Time Monitoring of Infiltration and contamination from Paste Tailing Site', in H Quelopana (ed.), Paste 2020: 23rd International Conference on Paste, Thickened and Filtered Tailings
, Gecamin Publications, Santiago, https://doi.org/10.36487/ACG_repo/2052_92
Mining facilities store process water or paste slurry. Lateral and vertical water percolation may create major problems concerning dam safety and environmental impact. Means for monitoring the saturated zone is widely used, but none concerning the unsaturated zone (vadose zone). A novel Vadose Zone Monitoring System (VMS) was developed at Ben Gurion University in Israel. VMS units include a set of advanced water and pressure sensors along with sampling ports. The units are mounted on a flexible sleeve which is installed through dedicated uncased small diameter boreholes. Through a control panel on the surface, data is transmitted via a cloud-based server directly to the client’s dedicated application.
Over the past decade, the VMS was successfully installed in a variety of scientific and commercial projects on water infiltration and contaminant transport from land surface to the groundwater in a variety of geological and hydrological setups. Recently, fertilizers’ producer in Israel (ICL), installed several VMS stations under phosphogypsum waste lagoons for monitoring the potential leaks from the bottom of lagoons to the subsurface, and one system in in an earthen dam for monitoring its safety status. The case study deals with contamination that was discovered in the aquifer. Continuous monitoring of water percolation beneath the ponds indicated that the levels of water percolation and pollution potential from these ponds are relatively low and therefore environmentally safe. These findings were accepted by the environmental authorities and the client wrote: "The VMS already had an important use, in proving the authorities that the contamination is from another source and not from our cell. We couldn't have done it any other way".
Implementing of the VMS systems at the above case and other cases produced real time information which has proved to be critical for maintaining long term safe operation of tailing sites.
Freeze, A. (9/7/2010) ‘Influence of the Unsaturated Flow Domain on seepage Through Earth Dams’, Water resources Research.
Dahan, O., McDonald, E. and Young, M. (2003) ‘Development of a flexible TDR probe for deep vadose zone monitoring’, Vadose Zone Journal.