HR: 14:10h
AN: NS33A-03    [Abstracts]
TI: Time-Lapse Electrical Resistivity Monitoring of the Remediation of a Saline Groundwater Plume
AU: * Hayley, K
EM: khhayley@ucalgary.ca
AF: Department of Geosciences University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
AU: Bentlay, L R
EM: lbentley@ucalgary.ca
AF: Department of Geosciences University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
AU: Gharibi, M
EM: mgharibi@ucalgary.ca
AF: Department of Geosciences University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
AB: Time-lapse electrical resistivity (ER) surveys are used to monitor the movement and remediation of a saline contaminant plume over the span of three years. Temperature is responsible for a large proportion of the observed ER changes. A temperature resistivity relationship is developed through laboratory testing on core from the site and analysis of petrophysical models. We present a protocol for removing the effects of temperature from ER difference images. Saturation changes also contribute to changes in the ER images. However, at this site, saturation is too spatially heterogeneous to apply a simple correction as was done with temperature. We show that the magnitude of the saturation changes are low and present an analysis of the uncertainty this introduces into the image interpretation. After accounting for temperature variations, we observe changes in the subsurface ER distribution that are consistent with depression focused recharge, solute flushing, and spatially variable effectiveness of the remediation program.
DE: 1835 Hydrogeophysics
DE: 1859 Rocks: physical properties
DE: 1895 Instruments and techniques: monitoring
DE: 5109 Magnetic and electrical properties (0925)
DE: 5134 Thermal properties
SC: Near-Surface Geophysics [NS]
MN: 2007 Fall Meeting