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Monitoring the Performance of Mine Site Reclamation
Published in Bruno Bussière, Marie Guittonny, Hard Rock Mine Reclamation, 2020
Bruno Bussière, Thomas Pabst, Vincent Boulanger-Martel, Marie Guittonny, Benoît Plante, Carmen Neculita, Sylvette Awoh, Mamert Mbonimpa, Isabelle Demers, Abdelkabir Maqsoud, Adrien Dimech, Pier-Luc Labonté-Raymond
In this context, hydrogeophysical methods have been suggested since they provide estimations of physical parameters with large spatial extensions (Rubin and Hubbard 2006). Radar tomography or electrical resistivity tomography (ERT) is frequently used to image the spatial distribution of dielectric constant ε or electrical conductivity σ, respectively. The investigated volume usually ranges from one to several hundred cubic meters (Binley et al. 2015). The distribution of ε or σ can be translated into volumetric water content θ in the medium according to empirical relationships similar to Topp’s equation mention previously to interpret TDR results. Time-lapse ERT (also referred as geoelectrical monitoring) is one of the most promising approaches among hydrogeophysical methods for performance monitoring because permanent systems can be installed at reclaimed mine sites where autonomous monitoring can be carried out remotely (see Falzone et al. 2019 for a review of time-lapse ERT applications). Such monitoring systems can provide hydrogeophysical data with high spatio-temporal resolution, which can be used as complementary data to extend spatially local hydrogeological measurements for performance monitoring. Finally, the continuous monitoring can also be complemented with larger geophysical radar or ERT investigations on a yearly basis, for example.
Determination of moisture content and soil suction in engineered fills using electrical resistivity
Published in N. Khalili, A.R. Russell, A. Khoshghalb, Unsaturated Soils: Research & Applications, 2020
R.M. Hen-Jones, P.N. Hughes, S. Glendinning, D.A. Gunn, J.C. Chambers, P.B. Wilkinson, S. Uhlemann
Resistivity imaging techniques such as Electrical Resistivity Tomography (ERT) rely on using groups of relatively closely-spaced electrodes and therefore have the potential to provide far higher resolution geotechnical information. These techniques work on the principle that high soil resistivities are caused mainly by a lack of ground moisture, and vice versa, and can therefore be used to infer the distribution of ground moisture, which acts to decrease soil shear strength. For this reason, and due to the fact that it is also sensitive to lithology, two-dimensional ERT has been well-established as a means of subsurface hydrogeological investigation (e.g. Yamakawa et al. 2012, Zhou et al. 2002). Although there is a wealth of on-going research into three-dimensional ERT (using electrode arrays) as a means of monitoring slope stability (Chambers et al. 2011, Friedel et al. 2006), relevant geophysical-geotechnical relationships require further validation. As elevated moisture contents and a corresponding reduction of soil suction are associated with shear failure, their interaction with soil resistivity is key to the development of a slope stability assessment system.
Biodegradation of Persistent Organic Pollutants
Published in Sunil Kumar, Zengqiang Zhang, Mukesh Kumar Awasthi, Ronghua Li, Biological Processing of Solid Waste, 2019
Kanchan Kumari, Ankur Khare, Siratun Montaha S. Shaikh, Pradip S. Jadhao
Time-lapse electrical resistivity tomography (ERT), coupled with radar techniques, is a proven geophysical method for conducting temporal change assessment in subsurface electrical conductivity. This technique overcomes the low-density post-amendment emplacement monitoring in the target vadose region by enhancing and complementing conventional sampling-based methods for assessment of biostimulation-based emplacement remediation. For effective management of subsurface bioremediation systems, in addition to the existing biogeochemical properties of pore fluid or sediment and redox zonation, information regarding changes in the biogeochemical characteristics due to fluid introduction or replacement by amendment are often required. Microbial mediated biogeochemical changes have also been monitored using ERT (Johnson et al., 2015; Snieder et al., 2007). Biofilm formation; microbial growth; microbial metabolic activity; and the associated by-products such as secondary minerals, biogenic gases, or mineral dissolution have been shown to change the interfacial electric property of the geologic media (Davis et al., 2006; Snieder et al., 2007).
Application of near infrared spectroscopy in sub-surface monitoring of petroleum contaminants in laboratory-prepared soils
Published in Soil and Sediment Contamination: An International Journal, 2023
Hanly S. Bingari, Andy Gibson, Emily Butcher, Richard Teeuw, Fay Couceiro
Surveys to detect, quantify, and monitor oil movement on different substrates (soil and water) are normally done using conventional invasive ground investigation techniques, such as boreholes, sampling, and associated laboratory testing. Although these approaches construct a robust geochemical characterization of contamination, they can be expensive, require safe disposal of used samples, and provide only a discontinuous sampling. Surface geophysics is also effective. Electrical Resistivity Tomography (ERT) surveying, either on its own or in combination with other geophysical techniques, is a proven method for oil contamination investigation (Cassiani et al. 2014; Coria et al. 2009; Delgado-Rodríguez et al. 2014; Ioane et al. 1999). The principle used is to delineate contaminated sites based on readings of apparent resistivity from an electrode array and identify anomalies that can be related to the presence of petroleum relative to the background (Brown et al. 2003; Delgado-Rodríguez et al. 2006a, 2006b; Shevnin et al. 2003). Problems with these techniques, however, arise due to the often cumbersome equipment set up required and the fact that readings can be affected by many factors including soil/rock type, clay content, moisture content, salinity, and electrode geometry.
New deep electrical resistivity tomography in the High Agri Valley basin (Basilicata, Southern Italy)
Published in Geomatics, Natural Hazards and Risk, 2019
The electrical resistivity tomography (ERT) allows the realization of an extreme detail image with regard to the areal behaviour of the electrical resistivity along the plane of the vertical section passing through the chosen profile. In detail, the remarkable resolution obtained through this technique allows to discriminate much more effectively the resistivity contrasts present in the subsoil. This technique has been widely applied in environmental and engineering geophysics to obtain 2D and 3D high-resolution images of the resistivity subsurface patterns in areas of complex geology at shallow depths (Giano et al. 2000; Suzuki et al. 2000; Demanet et al. 2001; Steeples 2001; Caputo et al. 2003; Improta et al. 2010; Stabile et al. 2014; Seminsky et al. 2016; Kolawole et al. 2018).