High-resolution ERT imaging of DNAPL contamination at complex soil remediation sites

Yang，Lichun1; Yang，Dikun1; Yuan，Quan2

10.1190/segam2021-3583389.1

2021

1052-3812

1949-4645

SEG Technical Program Expanded Abstracts

2021-September

1961-1965

Electrical resistivity tomography (ERT) has been extensively used in the investigation of contaminated sites. We report a case study at a DNAPL (dense non-aqueous phase liquid) remediation site in a factory, where the ERT data are complicated by a reinforced concrete layer with an embedded wire mesh on top of the soil. The wire mesh, as part of the infrastructure, imposes significant difficulties in the imaging of DNAPL. First, the inversion, as used in the conventional ERT data processing, cannot properly image the thin and highly conductive wire mesh. Second, the wire mesh creates a short-circuit for the current on the surface, so little current can reach the depth of DNAPL, and the data become insensitive to the sought targets. In this study, we improve the ERT imaging resolution for DNAPL by two ways. First, we recover a high conductivity for the top layer to sufficiently represent the effect of the wire mesh; then, this layer is treated as known and excluded from the inversion. Second, additional downhole electrodes are placed into the pumping wells used for remediation, so more information from the depth can be obtained. Our simulation and field data inversion both demonstrate the effectiveness of our advanced inversion techniques and downhole electrodes in improving the resolution of ERT imaging in complex exploration environments.

第一 ; 通讯

英语

EI

20215011324984

Data handling ; Mesh generation ; Reinforced concrete ; Soil conservation ; Wire

Concrete:412 ; Soils and Soil Mechanics:483.1 ; Metal Forming:535.2 ; Data Processing and Image Processing:723.2 ; Computer Applications:723.5 ; Combinatorial Mathematics, Includes Graph Theory, Set Theory:921.4

2-s2.0-85120992008

Scopus

1.Department of Earth and Space Sciences,Southern University of Science and Technology,China
2.Geomative Co. Ltd.,

Yang，Lichun,Yang，Dikun,Yuan，Quan. High-resolution ERT imaging of DNAPL contamination at complex soil remediation sites[C],2021:1961-1965.