title: Electrical resistivity tomography to monitor enhanced biodegradation of hydrocarbons with Rhodococcus erythropolis T902.1 at a pilot scale.
abstract: Petroleum hydrocarbons (HC) represent the most widespread contaminants and in-situ bioremediation remains a competitive treatment in terms of cost and environmental concerns. However, the efficiency of such a technique (by biostimulation or bioaugmentation) strongly depends on the environment affected and is still difficult to predict a priori. In order to overcome these uncertainties, Electrical Resistivity Tomography (ERT) appears as a valuable non-invasive tool to detect soil heterogeneities and to monitor biodegradation. The main objective of this study was to isolate an electrical signal linked to an enhanced bacterial activity with ERT, in an aged HC-contaminated clay loam soil. To achieve this, a pilot tank was built to mimic field conditions. Compared to a first insufficient biostimulation phase, bioaugmentation with Rhodococcus erythropolis T902.1 led to a HC depletion of almost 80% (6900 to 1600ppm) in 3months in the center of the contaminated zone, where pollutants were less bioavailable. In the meantime, lithological heterogeneities and microbial activities (growth and biosurfactant production) were successively discriminated by ERT images. In the future, this cost-effective technique should be more and more transferred to the field in order to monitor biodegradation processes and assist in selecting the most appropriate remediation technique.
authors.affiliation: Bio-industries Research Unit, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium; Walloon Center of Industrial Biology, Department of Health Sciences, University of Liège, Chemin de la Vallée 2 (B40), 4000 Liège, Belgium. Electronic address: tmasy@ulg.ac.be.
authors.forename: Thibaut
authors.initials: T
authors.lastname: Masy
authors.affiliation: Applied Geophysics Research Unit, Department ArGEnCo, Faculty of Applied Sciences, University of Liège, Allée de la Découverte 9 (B52), 4000 Liège, Belgium. Electronic address: d.caterina@fz-juelich.de.
authors.forename: David
authors.initials: D
authors.lastname: Caterina
authors.affiliation: Sanifox SPRL, Rue Enhet-Centre 47, 5590 Chevetogne, Belgium.
authors.forename: Olivier
authors.initials: O
authors.lastname: Tromme
authors.affiliation: Sanifox SPRL, Rue Enhet-Centre 47, 5590 Chevetogne, Belgium.
authors.forename: Benoît
authors.initials: B
authors.lastname: Lavigne
authors.affiliation: Bio-industries Research Unit, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium; Walloon Center of Industrial Biology, Department of Health Sciences, University of Liège, Chemin de la Vallée 2 (B40), 4000 Liège, Belgium.
authors.forename: Philippe
authors.initials: P
authors.lastname: Thonart
authors.affiliation: Walloon Center of Industrial Biology, Department of Health Sciences, University of Liège, Chemin de la Vallée 2 (B40), 4000 Liège, Belgium.
authors.forename: Serge
authors.initials: S
authors.lastname: Hiligsmann
authors.affiliation: Applied Geophysics Research Unit, Department ArGEnCo, Faculty of Applied Sciences, University of Liège, Allée de la Découverte 9 (B52), 4000 Liège, Belgium.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Nguyen
mesh_terms: D001673:Biodegradation, Environmental; D017097:Electric Impedance; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006838:Hydrocarbons / Q000378:metabolism*; D010578:Petroleum / Q000378:metabolism*; D012240:Rhodococcus / Q000378:metabolism*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis*; D014054:Tomography
chemical_list: D006838:Hydrocarbons; D010578:Petroleum; D012989:Soil Pollutants
keywords: Bioaugmentation; Bioremediation; Electrical resistivity tomography (ERT); Hydrocarbons (HC); Pilot scale; Rhodococcus erythropolis