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Bioaugmentation of Chlorinated Solvents

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Bioaugmentation of Chlorinated Solvents BIOAUGMENTATION FOR REMEDIATION OF CHLORINATED SOLVENTS: TECHNOLOGY DEVELOPMENT, STATUS, AND RESEARCH NEEDS October 2005 GeoSyntec Consultants TABLE OF CONTENTS LIST OF TABLES ...........................................................................................................................................III LIST OF FIGURES .........................................................................................................................................III ACRONYMNS AND ABBREVIATIONS........................................................................................................V FOREWORD...................................................................................................................................................VII EXECUTIVE SUMMARY ............................................................................................................................... IX 1. INTRODUCTION ..........................................................................................................................................1 2. EARLY DEVELOPMENT OF BIOAUGMENTATION.............................................................................5 3. RECENT PROGRESS IN CHLORINATED SOLVENT BIOREMEDIATION .....................................13 4. DEHALORESPIRATION: THE KEY PROCESS UNDERLYING CURRENT BIOAUGMENTATION PRACTICES..............................................................................................................................................................19 4.1 THE UBIQUITY CONCEPT REVISITED ............................................................................................19 4.2 PHYLOGENY, ORIGIN, AND CHARACTERISTICS OF DEHALOCOCCOIDES ORGANISMS........................21 4.3 Conclusions Regarding the Microbiology of Dehalorespiration.................................................24 4.4 EMERGING BIOAUGMENTATION APPLICATIONS OF DEHALORESPIRATION ........................................25 5. THE BUSINESS OF BIOAUGMENTATION ...........................................................................................29 5.1 BIOAUGMENTATION CULTURES USED IN FIELD DEMONSTRATIONS .................................................29 5.2 FACTORS KNOWN TO AFFECT CULTURE PERFORMANCE ...............................................................35 5.2.1 Oxygen Tolerance.......................................................................................................................35 5.2.2 Geochemical Conditions ..........................................................................................................35 5.2.3 Electron Donor Selection..........................................................................................................36 5.2.4 VOC Concentration ....................................................................................................................37 5.2.5 Inhibition by Selected VOCs....................................................................................................37 5.3 PATHOGENICITY ..........................................................................................................................38 5.4 CULTURE QUALITY ASSURANCE/QUALITY CONTROL......................................................................39 6. BIOAUGMENTATION IN THE FIELD......................................................................................................43 6.1 DECIDING WHETHER BIOAUGMENTATION IS NEEDED.....................................................................43 6.2 DECIDING WHEN TO BIOAUGMENT................................................................................................45 Bioaugmentation for Remediation of Chlorinated Solvents: i Technology Development, Status, and Research Needs GeoSyntec Consultants 6.3 METHODS TO DETERMINE THE NEED FOR BIOAUGMENTATION........................................................45 6.3.1 Direct Detection ..........................................................................................................................46 6.3.2 Microcosm Testing.....................................................................................................................46 6.3.3 Current Practices Based on Field Observations ................................................................47 6.4 SURVIVAL OF INJECTED ORGANISMS.............................................................................................47 6.5 MICROBIAL TRANSPORT IN GROUNDWATER ..................................................................................49 6.6 FIELD APPLICATION OF BIOAUGMENTATION...................................................................................52 6.7 EMERGING PRACTICES: BIOAUGMENTATION FOR DNAPL SOURCE ZONE TREATMENT....................57 7. REGULATORY CONSIDERATIONS .......................................................................................................59 8. INFORMATION AND RESEARCH NEEDS ............................................................................................61 8.1 CULTURE PRODUCTION AND QUALITY ASSURANCE/QUALITY CONTROL ..........................................61 8.2 TECHNOLOGY DESIGN, IMPLEMENTATION, AND PERFORMANCE VALIDATION ...................................62 9. ACCELERATING TECHNOLOGY TRANSITION..................................................................................65 10. SUMMARY .................................................................................................................................................67 11. REFERENCES...........................................................................................................................................69 APPENDIX A: BIOAUGMENTATION CULTURE VENDOR SURVEY................................................ A-1 APPENDIX B: BIOAUGMENTATION CASE STUDIES......................................................................... A-1 Bioaugmentation for Remediation of Chlorinated Solvents: ii Technology Development, Status, and Research Needs GeoSyntec Consultants LIST OF TABLES Table 1: Characterization of Commercial Bioaugmentation Inocula .........................................6 Table 2: Summary of Dehalogenating Bacteria Detected in Pure and Mixed Cultures ...........20 Table 3: Bioaugmentation Cultures and Mixed Consortia Used for Treatment of Chlorinated Solvents in Groundwater ........................................................................30 Table 4: Summary of Quality Assurance/Quality Control Practices for the Production of Commercially Available Bioaugmentation Cultures...........................32 Table 5: Factors Impacting Microbial Transport and Growth..................................................50 Table 6: Summary of Bioaugmentation Field Demonstrations for Chlorinated Solvents in Groundwater............................................................................................53 Table 7: Summary of Bioaugmentation Field Protocols...........................................................55 Table 8: DNAPL Mass Transfer Enhancements Achieved Using Enhanced Bioremediation ...........................................................................................................58 LIST OF FIGURES Figure 1a: Pathways for the Degradation of Chlorinated Ethenes...............................................14 Figure 1b: Pathways for the Degradation of Chlorinated Ethanes...............................................15 Figure 1c: Pathways for the Degradation of Chlorinated Methanes............................................16 Figure 2: Dendogram of the Groups and Subgroups of the Genus Dehalococcoides................22 Bioaugmentation for Remediation of Chlorinated Solvents: iii Technology Development, Status, and Research Needs GeoSyntec Consultants This page intentionally left blank Bioaugmentation for Remediation of Chlorinated Solvents: iv Technology Development, Status, and Research Needs GeoSyntec Consultants ACRONYMNS AND ABBREVIATIONS 1,1,1-TCA 1,1,1-trichloroethane 1,1,2,2-TeCA 1,1,1,1-tetrachloroethane 1,1-DCA 1,1-dichloroethane 1,2-DCA 1,2-dichloroethane AFB Air Force Base APC Applied Power Concepts ATP adenosine triphosphate BCI Bioremediation Consulting Inc. BDI Bio-Dechlor INOCULUM bgs below ground surface bvcA vinyl chloride reductase CA chloroethane CAH carbonic anhydrase CDM Camp Dresser and McKee CF chloroform CFU colony-forming unit cis-DCE cis-1,2-dichloroethane CT carbon tetrachloride CVOC chlorinated volatile organic compound DCA dichloroacetic acid DCE dichloroethene DGGE denaturing gradient gel electrophoresis DHC Dehalococcoides DLVO Derjaquin-Landau-Verwey-Overbeek DNA deoxyribonucleic acid DNAPL dense, non-aqueous phase liquids DO dissolved oxygen DOC dissolved organic carbon DoD Department of Defense DOE Department of Energy eBAC total bacteria ERM Environmental Resources Management ESTCP Environmental Security Technology Certification Program GEM genetically engineered microorganism H2S hydrogen sulfide HRC Hydrogen Release Compound ISB In Situ Bioremediation LC-34 Launch Complex-34 LLNL Lawrence Livermore National Laboratory MCL Maximum Contaminant Level MGN methanogen MOE Ministry of the Environment ND non-detect NPL National Priorities List O&M operations and maintenance Bioaugmentation for Remediation of Chlorinated Solvents: v Technology Development, Status, and Research Needs GeoSyntec Consultants ORP oxidation/reduction potential OSHA Occupational Safety and Health Administration PAH polynuclear aromatic hydrocarbon PCB polychlorinated biphenyl PCE tetrachloroethene
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