Coupling Physical and Chemical-Biological Techniques for the Remediation of Contaminated Soils and Groundwater

Soil and groundwater contamination with hazardous substances, notably heavy metals, chlorinated ethenes, and petroleum hydrocarbons, is an urgent global environmental concern. To address and remediate these contaminated sites, the deployment of efficient and sustainable strategies is paramount. While traditional remediation methods, both in-situ and ex-situ, predominantly focus on either physical or chemical-biological interventions, the synergistic use of these techniques is emerging as an effective remediation strategy. In this context, hydraulic manipulation techniques, specifically groundwater circulation wells (GCWs) and coaxial groundwater circulation (CGC) in conjunction with air sparging (AS), have demonstrated efficacy in integrating chemical-physical and biological remediation modalities. This chapter offers a rigorous overview of the principles and methodologies behind the combined use of physical and chemical-biological remediation techniques in treating contaminated soils and groundwater. The advantages, constraints, and recent innovations in these strategies are discussed comprehensively. By providing an in-depth analysis of hydraulic manipulation systems, this chapter seeks to facilitate the selection and deployment of optimal remediation strategies tailored to distinct contamination scenarios. The potential of GCW and CGC-AS methodologies in enhancing contaminant extraction and ensuring sustainable site rehabilitation is emphasized. Through meticulously chosen case studies, the chapter elucidates the principles, applications, benefits, and limitations inherent to the integration of these technologies within multifaceted hydrogeological environments.