Book Description

The contamination of groundwater and subsurface soil in the United States is a widespread and challenging problem. There are estimated to be in excess of 200,000 sites requiring some form of remediation, and many of these sites potentially threaten groundwater resources. In areas where the groundwater resources are not considered at risk, there are frequently impediments to the reuse of brownfield sites. In addition, for many subsurface geological settings, conventional treatment methods, such as pump-and-treat technology, can be costly and inefficient. Emerging in situ groundwater and subsurface soil treatment technologies may provide effective, lower-cost alternatives, and it is important to fully understand all aspects of any new and innovative technology. This guidance document was developed to outline the technical and regulatory requirements of in situ chemical oxidation (ISCO), a group of technologies involving various combinations of oxidants and delivery techniques. The primary oxidants addressed in this document are hydrogen peroxide, potassium and sodium permanganate, sodium persulfate, and ozone. The effectiveness of some of these oxidants can be enhanced through activation (Fenton's reagent, activated persulfate) and used in conjunction with other oxidants (perozone). Additionally, this document is intended to expedite movement to a consensus on regulatory requirements through the Interstate Technology & Regulatory Council concurrence process. It should prove useful to regulators, stakeholders, consultants, and technology implementers. The document is divided into sections consisting of technology overview and applicability, remedial investigations, safety concerns, regulatory concerns, injection design, monitoring, stakeholder concerns, and case studies. From a regulatory perspective, the most important sections of the document are identification of injection restrictions, implementation, and post-closure monitoring.