FINAL Protocol forIn Situ Bioremediation of Chlorinated Solvents Using Edible Oil FINAL PROTOCOL FOR IN SITU BIOREMEDIATION OF CHLORINATED SOLVENTS USING EDIBLE OIL October 2007 Prepared for: Air Force Center for Engineering and the Environmental Environmental Science Division Technology Transfer Outreach Office ACKNOWLEDGEMENTS This protocol was prepared by Solutions IES, Inc. (Solutions IES), Terra Systems, Inc. (TSI), and Parsons Infrastructure & Technology Group, Inc. (Parsons) under contract to the Air Force Center for Engineering and the Environmental (AFCEE). This document is intended to assist AFCEE and their United States Department of Defense (DoD) technology-transition partners in evaluating and applying edible oil and edible oil emulsions as a long-lasting organic substrate to enhance the in situ anaerobic bioremediation of chlorinated solvents in groundwater. The authors acknowledge the assistance of numerous individuals who provided management, oversight, and review services. These individuals and their affiliations are listed in Appendix A. DISCLAIMER This protocol is a work prepared for the Technology Transfer Outreach Office of the United States Air Force Center for Engineering and the Environmental (AFCEE) by Solutions-IES, Inc. Terra Systems, Inc., Parsons Infrastructure & Technology Group, Inc., and representatives from AFCEE. In no event shall either the United States Government, Solutions-IES, Inc., Terra Systems, Inc., or Parsons Infrastructure & Technology Group, Inc. have any responsibility or liability for any consequences of any use, misuse, inability to use, or reliance upon the information contained herein; nor does these entities warrant or otherwise represent in any way the accuracy, adequacy, efficacy, or applicability of the contents hereof. TABLE OF CONTENTS Page SECTION 1 - USING THE EDIBLE OIL PROCESS.....................................................1-1 1.1 Introduction ..........................................................................................................1-1 1.2 Intended Use of this Document ............................................................................1-2 1.3 Following the Edible Oil Process.........................................................................1-3 1.4 Defining Remedial Objectives .............................................................................1-4 1.5 Enhanced Anaerobic Bioremediation of Chlorinated Solvents............................1-6 1.6 Overview of the Edible Oil Process ...................................................................1-14 1.6.1 Treatment System Configurations..........................................................1-15 1.6.1.1 Source Areas..........................................................................1-16 1.6.1.2 Permeable Biobarriers...........................................................1-16 1.6.2 Edible Oil................................................................................................1-16 1.6.3 Application Methods..............................................................................1-18 1.6.3.1 Pure Edible Oil......................................................................1-18 1.6.3.2 Oil-in-Water Emulsions.........................................................1-19 1.6.4 Design and Implementation of Edible Oil Applications ........................1-21 SECTION 2 - PRELIMINARY SCREENING ................................................................2-1 2.1 Road Map for Preliminary Screening...................................................................2-1 2.2 Site Screening Considerations..............................................................................2-3 2.3 Site Conditions Suitable for Edible Oil Applications...........................................2-5 2.3.1 Potential for Reductive Dechlorination....................................................2-6 2.3.1.1 Types of Groundwater Environments......................................2-6 2.3.1.2 Assessing the Potential for Reductive Dechlorination ............2-6 2.3.1.3 Potential for Biogeochemical Reduction.................................2-8 2.3.2 Source Area and Plume Size ....................................................................2-9 2.3.3 Depth to Groundwater ..............................................................................2-9 2.3.4 Heterogeneity and Hydraulic Conductivity............................................2-10 2.3.5 Groundwater Flow..................................................................................2-10 2.3.6 Competing Electron Acceptors...............................................................2-11 2.3.7 pH and Alkalinity ...................................................................................2-12 2.4 Proceeding with the Edible Oil Process .............................................................2-12 SECTION 3 - PILOT TEST PLANNING, IMPLEMENTATION, AND MONITORING .......................................................................................3-1 3.1 Defining Pilot Test Objectives .............................................................................3-1 3.2 Development of a Site-Specific Test Plan............................................................3-2 3.3 Pilot Test Configurations......................................................................................3-3 3.3.1 Single Well Push-Pull Injection Tests......................................................3-4 3.3.1.1 Single-Stage Push-Pull Test ....................................................3-4 3.3.1.2 Two-Stage Push-Pull Test .......................................................3-6 -i- TABLE OF CONTENTS (Continued) Page 3.3.2 Multi-Well Injection Tests .......................................................................3-7 3.4 Monitoring During the Injection Process .............................................................3-7 3.4.1 Radius of Influence Evaluation ................................................................3-8 3.4.1.1 Water Soluble Groundwater Tracers .......................................3-8 3.4.1.2 Oil Soluble Tracers..................................................................3-9 3.4.1.3 Soil Analysis for Determining Substrate Distribution...........3-10 3.4.2 Effect of Oil Injection on Formation Permeability.................................3-10 3.5 Monitoring Networks.........................................................................................3-10 3.5.1 Number and Location of Monitoring Points ..........................................3-11 3.5.2 Analysis of Substrate Distribution..........................................................3-13 3.5.3 Monitoring Frequency............................................................................3-14 3.6 Performance Monitoring Protocols....................................................................3-14 3.6.1 Contaminants and Dechlorination Products ...........................................3-15 3.6.2 Biogeochemistry.....................................................................................3-15 3.6.3 Indicators of Organic Carbon .................................................................3-15 3.6.4 Microbiological Characterization...........................................................3-16 3.6.5 Soil Characterization..............................................................................3-18 3.6.6 Soil Gas..................................................................................................3-19 3.6.7 Downgradient Water Quality .................................................................3-19 3.7 Proceeding to Full-Scale Application.................................................................3-19 SECTION 4 - DESIGN OF FULL-SCALE EDIBLE OIL APPLICATIONS.................4-1 4.1 Remedial Objectives and Edible Oil Configurations ...........................................4-1 4.1.1 Remedial Objectives.................................................................................4-1 4.1.2 Treatment System Configurations............................................................4-2 4.1.2.1 Source Areas............................................................................4-2 4.1.2.2 Permeable Biobarriers for Plume Treatment ...........................4-3 4.2 General Design Parameters ..................................................................................4-4 4.2.1 Treatment Zone Dimensions ....................................................................4-4 4.2.2 Amount of Oil Required for Effective Treatment ....................................4-6 4.2.2.1 Site Hydrogeology and Volume of Water to be Treated .........4-6 4.2.2.2 System Design Life..................................................................4-7 4.2.2.3 Hydrogen Demand...................................................................4-8 4.2.2.4 Additional Hydrogen Demands and Organic Carbon Released Downgradient.........................................................4-10 4.2.2.5 Oil Retention within the Aquifer Matrix ...............................4-10 4.2.2.6 Chlorinated Solvent Partitioning into Oil..............................4-11 4.2.2.7 Summary – How Much Oil Do You Need?...........................4-13 4.2.3 Amendments...........................................................................................4-13 4.2.4 Source of Make-up Water or Chase Water.............................................4-15 4.2.5 Dilution or Chase Water Volumes .........................................................4-15