Objective: In situ chemical oxidation (ISCO) and in situ anaerobic bioremediation (ISAB) technologies are being implemented at numerous private and Department of Defense sites. With both approaches, a chemical reagent (aqueous chemical oxidant or organic substrate) is distributed throughout the treatment zone using a system of temporary or permanent wells. For the technologies to be effective, sufficient reagent must be brought into contact with the contaminant to be treated. The objective of this project is to develop a set of tools to assist design engineers in developing effective, reasonably efficient systems for distributing aqueous amendments for in situ treatment of groundwater contaminants. Primary applications for the tools will be for design of ISCO systems using permanganate and ISAB systems using soluble substrates and emulsified oil. As technology evolves, this general approach should be applicable to the distribution of other aqueous amendments. Technology Description: Currently available numerical models first will be used to examine the effects of site conditions (e.g., permeability, contaminant distribution, and site heterogeneity) and design variables (location of wells, injection rates, volumes, amount of reagent, etc.) on reagent distribution and associated contact efficiency. Results from the numerical model simulations will be used to develop simple curves relating reagent distribution efficiency to important design parameters (e.g., pore volumes of injection fluid and amount of reagent) and guide designers in the proper selection of these parameters. The results also will be used in the development of a simple, spreadsheet-based tool to assist in the design of injection systems for treatment of contaminated aquifers using permanganate, soluble substrates, and emulsified oil. This design tool will allow engineers to evaluate the effect of different design variables (well spacing, amount of reagent, injection rate, etc.) on remediation system cost and expected performance. Worksheets will be developed for each of the major design alternatives (e.g., type of reagent and type of injection system). Training materials will be developed to walk new users through each worksheet of the design tool and provide guidance on selection of important design parameters. Expected Benefits: At some sites, ISCO and ISAB work very well, resulting in substantial reductions in contaminant concentration and mass, but at many sites the remediation process does not meet cleanup objectives due to poor delivery of the chemical reagent to the treatment zone. By providing design engineers with a simple easy-to-use tool for planning aqueous injection systems, the performance of these systems can be substantially improved and costs reduced. (Anticipated Project Completion - 2009) Principal Investigator: Dr. Robert Borden North Carolina State University Campus Box 7908 Raleigh, NC 27695 Telephone: (919) 515-1625 Fax: (919) 515-7908 E-mail: rcborden@eos.ncsu.edu DoD Liaison: Ms. Erica S.K. Becvar HQ AFCEE/TDE 3300 Sidney Brooks, Building 532 Brooks City-Base, TX 78235-5112 Telephone: (210) 536-4314 Fax: (210) 536-5989 E-mail: erica.becvar@brooks.af.mil | 
