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USGS · 70193758

Assessing field-scale biogeophysical signatures of bioremediation over a mature crude oil spill

Lee Slater·Dimitrios Ntarlagiannis·Estella Atekwana·Farag Mewafy·Andre Revil·Magnus Skold·Yuri Gorby·Frederick D. Day-Lewis·John W. Lane·Dale D. Werkema·Jared J. Trost·Geoffrey N. Delin·William N. Herkelrath
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Abstract

We conducted electrical geophysical measurements at the National Crude Oil Spill Fate and Natural Attenuation Research Site (Bemidji, MN). Borehole and surface self-potential measurements do not show evidence for the existence of a biogeobattery mechanism in response to the redox gradient resulting from biodegradation of oil. The relatively small self potentials recorded are instead consistent with an electrodiffusion mechanism driven by differences in the mobility of charge carriers associated with biodegradation byproducts. Complex resistivity measurements reveal elevated electrical conductivity and interfacial polarization at the water table where oil contamination is present, extending into the unsaturated zone. This finding implies that the effect of microbial cell growth/attachment, biofilm formation, and mineral weathering accompanying hydrocarbon biodegradation on complex interfacial conductivity imparts a sufficiently large electrical signal to be measured using field-scale geophysical techniques.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 47.56390159961883° to 47.58393661978134° latitude; -95.1170539855957° to -95.08100509643555° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Lee Slater, Dimitrios Ntarlagiannis, Estella Atekwana, Farag Mewafy, Andre Revil, Magnus Skold, Yuri Gorby, Frederick D. Day-Lewis, John W. Lane, Dale D. Werkema, Jared J. Trost, Geoffrey N. Delin, William N. Herkelrath. 2011. Assessing field-scale biogeophysical signatures of bioremediation over a mature crude oil spill. https://pubs.usgs.gov/publication/70193758

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