Multidisciplinary Characterization of Chlorinated Solvents Contamination and In-Situ Remediation with the Use of the Direct Current Resistivity and Time-Domain Induced Polarization Tomography

Aristeidis Nivorlis,Torleif Dahlin,Matteo Rossi,Nikolas Höglund,Charlotte Sparrenbom

doi:10.3390/geosciences9120487

Abstract

Soil contamination is a widespread problem and action needs to be taken in order to prevent damage to the groundwater and the life around the contaminated sites. In Sweden, it is estimated that more than 80,000 sites are potentially contaminated, and therefore, there is a demand for investigations and further treatment of the soil. In this paper, we present the results from a methodology applied in a site contaminated with chlorinated solvents, for characterization of the contamination in order to plan the remediation and to follow-up the initial step of in-situ remediation in an efficient way. We utilized the results from three different methods; membrane interface probe for direct measurement of the contaminant concentrations; seismic refraction tomography for investigating the depth to the bedrock interface; and direct current resistivity and time-domain induced polarization tomography to acquire a high-resolution imaging of the electrical properties of the subsurface. The results indicate that our methodology is very promising in terms of site characterization, and furthermore, has great potential for real-time geophysical monitoring of contaminated sites in the future.

Highlights

Soil contamination is a widespread problem in most developed countries due to the increased use of hazardous substances in the industry
It is imperative to know the boundaries of the bedrock interface
The results from the seismic refraction tomography indicate that the bedrock is dipping towards north-northwest, which, in combination with the groundwater flow, explains the migration of the PCE that led to the formation of the plume as showed from the Membrane Interface Probe (MIP)-soundings (Figure 2)

Summary

Introduction

Soil contamination is a widespread problem in most developed countries due to the increased use of hazardous substances in the industry. On basis of that framework, the Swedish Environmental Protection Agency (SEPA) has identified more than 80,000 potentially contaminated sites in Sweden [1]. Expansion of the cities pushes new construction towards many contaminated sites, which need to be treated urgently. The contaminated materials are often treated via transportation to landfills with (“dig and treat”) or without any treatment (“dig and dump”), introducing the risk of secondary exposure and/or movement of the problem. Because these techniques are associated with significant risk and long-term costs, SEPA (2014)

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Results

Conclusion