In Situ Chemical Oxidation

Chemical oxidation technologies are being used more often to remediate contaminated soils and groundwater. In order to ensure safety of human health and the environment, and to expedite deployment of these technologies, it is imperative regulators, facilities, and stakeholders be informed to the greatest extent possible.

ITRC's In Situ Chemical Oxidation Team will update and revise the current technical and regulatory guidance document, “Technical and Regulatory Guidance for In Situ Chemical Oxidation of Contaminated Soil and Groundwater (ISCO-1). A new chemical oxidant, persulfate, will be included in the updated document, along with a more detailed presentation of some of the key concepts of remedial design such as injection radius of influence, NOM oxidation and its effects on contaminant concentrations, and SOD test methods/interpretation of results. The team will also develop a methodology to evaluate ISCO effectiveness/technology selection based upon contaminated media and phase. New sections will be added regarding the utilization of chemical oxidation in conjunction with other technologies, more regulatory examples/policies will be gathered from states not included in ISCO-1, and the case studies will be presented in more detail. The new document, “Technical and Regulatory Guidance for In Situ Chemical Oxidation of Contaminated Soil and Groundwater, Second Edition (ISCO-2)” was released in January 2005.

The original ISCO internet training will continue to be presented in 2003. Feedback from the training indicates an interest in a collection of state regulatory policies/examples and a more in-depth presentation of case studies/lessons learned. The internet training will be updated to reflect any changes in the document, and it will either be lengthened to allow for a more in-depth presentation of case studies, or an advanced ISCO internet and/or classroom training will be developed.

Although chemical oxidation is not a completely new technology, it is one of the most misunderstood technologies. It is imperative to produce a guidance document to help regulators determine whether it is not only applicable but to ensure it is being implemented correctly using the appropriate reagents. Because the oxidants must be injected into the subsurface, an underground injection control permit will be required in most instances. There are both federal and state requirements that must be met before implementing this technology.

The market is very widespread and includes most types of subsurface contamination that requires corrective action. Chemical oxidation has been shown to be effective at remediating chlorinated solvents, petroleum products, and other organic chemicals including MTBE. Even though it may not be cost effective to remove grossly contaminated source areas, it has been shown to minimize off-site impacts by treating the downgradient plume.

This technology is focused with respect to the type of contamination that can be remediated, but it is national in the sense that there are facilities all over the country with contamination problems this technology can cost effectively manage.

The document/training will be the most complete compilation of knowledge on chemical oxidation to date. It will be invaluable to all parties in decision making for this technology.