IN SITU Chemical Reduction For Source Remediation

In situ chemical reduction (ISCR) is a general term for a suite of in situ groundwater remediation technologies that rely primarily on chemical reduction of contaminants. ISCR has been used for over 15 years for plume treatment, but its use for source treatment is more recent. This chapter provides the first integrated assessment of the entire suite of ISCR technologies, and describes the technical basis, engineering aspects, past experiences and future prospects for using ISCR to treat chlorinated solvent source zones. In situ chemical reduction of contaminants can occur through natural intrinsic biogeochemical processes, as a result of stimulating in situ microbial activity to form reducing minerals, or after direct injection of chemical reductants. The chapter includes case studies of several ISCR technologies and summarizes the lessons learned to date from research and field experience.