Practical Assessment and Optimization of Redox-Based Groundwater Remediation Technologies
ER-2308
Objective
Almost all approaches to remediation of groundwater contaminated with chlorinated solvents involve redox reactions, and many of the assessment criteria used to evaluate these remediation technologies are based on redox concepts. However, the existing redox-based assessment criteria [e.g., oxidation-reduction potential (ORP) and natural oxidant demand (NOD)] are not adequate for selecting among alternative technologies, and redox-based methods for optimization of particular technology deployments are not sufficiently well-developed to be used quantitatively. This project will overcome these insufficiencies by (i) re-evaluating traditional redox-based characterization methods in light of the current, improved understanding of subsurface redox processes; (ii) developing in situ chemical probe based redox characterization methods that are more precise and robust, and (iii) rigorously defining the relationship between results from these new characterization methods and the performance of redox-based remedies applied to particular sites.
Technical Approach
This project will address the three types of factors that determine the performance of redox technologies (thermodynamic, kinetic, and capacity) by focusing on chemical-probe based assays that represent dynamic, rather than static, characteristics of the system. For example, although they are widely used, platinum electrode measurements are of limited value in designing remediation systems because they respond to a wide range of redox-active species with variable and unknown sensitivities. In contrast, the chemical probes to be developed can target the species that are of primary interest in the design of a particular remediation system. Furthermore, utilizing in situ “push-pull” tests for measurement of aquifer properties will yield more accurate results than laboratory measurements based on collected core samples.
Benefits
The new tools developed will directly benefit the planning and implementation of remedies for chlorinated solvent contaminated groundwater. They will be applicable early in the site characterization process to help determine what remediation approach is best suited to the site. They also will be useful in a "before and after" mode to assess the effectiveness of augmentation/stimulation. Finally, they will help to determine when remediation activities at sites are not performing as anticipated and can provide an improved scientific basis for terminating remediation activities, if necessary. Training for the environmental engineering community will encourage adoption of these methods in assessment and optimization of full-scale remediation operations. (Anticipated Project Completion - 2016)
Points of Contact
Principal Investigator
Dr. Paul Tratnyek
Oregon Health & Science University
Phone: 503-748-1023
Fax: 503-748-1273
Document Types
- Fact Sheet - Brief project summary with links to related documents and points of contact.
- Final Report - Comprehensive report for every completed SERDP and ESTCP project that contains all technical results.
- Cost & Performance Report - Overview of ESTCP demonstration activities, results, and conclusions, standardized to facilitate implementation decisions.
- Technical Report - Additional interim reports, laboratory reports, demonstration reports, and technology survey reports.
- Guidance - Instructional information on technical topics such as protocols and user’s guides.
- Workshop Report - Summary of workshop discussion and findings.
- Multimedia - On demand videos, animations, and webcasts highlighting featured initiatives or technologies.
- Model/Software - Computer programs and applications available for download.
- Database - Digitally organized collection of data available to search and access.