Groundwater contamination and emergency response guide

Contents and Subject Index Part I Groundwater Contamination Response Methodology ACKNOWLEDGMENTS 2 1. INTRODUCTION 3 2. IDENTIFYING AND ASSESSING THE CONTAMINATION PROBLEM 5 Initial Assessment 5 Additional Data Collection and Assessment 13 Field Investigations 13 Field Mapping 13 Surface Geophysical Surveys 13 Test-Drill ing and Sampling 14 Monitor Well Installation 14 Borehole Geophysical Surveys 15 Hydraulic Testing 15 Water Quality Sampling 16 Chemical Analysis Methods 16 Overview 16 General Approach 18 Methods for Organic Chemicals 20 Other Classical Parameters 20 Quality Assurance/Quality Control 24 Integrating Data Collection and Analysis 24 3. DEVELOPING DECISION PARAMETERS 26 Ultimate Fate of Organics in Groundwater 26 vii viii Contents and Subject Index Step I-Preliminary Assessment 26 Information Requirements 26 Assessment of Fate 28 Step II-Revised Assessment 29 Types of Remedial Response 30 4. SELECTING A REMEDIAL RESPONSE 31 Preliminary Assessment 31 Development of Alternatives 36 Analysis of Alternatives 36 Selecting an Appropriate Remedial Action 37 Responding to Regulatory Requirements 38 REFERENCES . . 40 Part II Groundwater Contamination Response Desk Reference ACKNOWLEDGMENTS 42 1. GENERAL DESCRIPTION OF GROUNDWATER CONTAMINATION .. 43 Overview of Groundwater Hydrology and Contamination 43 Groundwater Hydrology 43 Groundwater Contamination 53 Causes and Prevention of Groundwater Contamination 58 Introduction 58 Sources 59 Land Disposal 59 Causes 59 Prevention 59 Surface Impoundments 60 Causes 60 Prevention 60 Mines 60 Causes 60 Prevention 60 Septic Systems 61 Causes 61 Prevention 61 Underground Petroleum Tanks 61 Causes 61 Prevention 61 Spills 61 Causes 61 Prevention 62 Case Histories 62 Case Study #1: TCE Contamination 62 Background 62 Contents and Subject Index ix Problem Identification 62 Problem Assessment 63 Remedial Action 64 Case Study #2: Benzene Contamination 64 Background 64 Problem Identification 64 Problem Assessment 65 Remedial Action 65 Case Study #3: POL Contamination 65 Background 65 Problem Identification 65 Problem Assessment 66 Remedial Action 66 Site A 66 Site B 67 Site C 67 Regulatory Summary 67 Introduction 67 Federal Statutes 68 Resource Conservation and Recovery Act of 1976 (RCRA) 68 Comprehensive Emergency Response, Compensation and Liability Act of 1980 (CERCLA, or Superfund) 68 Safe Drinking Water Act of 1974 71 Clean Water Act 71 Surface Mining Control and Reclamation Act of 1977 71 Toxic Substances Control Act (TSCA) 71 Uranium Mill Tailings Radiation Control Act 72 The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 72 Notification Requirements 72 Discovery of Groundwater Contamination While Monitoring an RCRA-Permitted Facility 72 Discovery of Groundwater Contamination Related to a FacHity not Permitted Under RCRA 73 Discovery of Groundwater Contamination not Related to Any Known Source 74 Developing Issues 74 Characterization of Polluted Groundwater 74 Extent and Degree of Contamination 75 Altered Potential for Groundwater Use 75 Treatability 77 2. FACTORS AFFECTING CONTAMINANT TRANSPORT 78 Hydrologic Cycle 78 Meteorological Effects on Groundwater Contamination 84 Geological Effects on Groundwater Contamination 87 Effects of Pumping on Contaminant Plumes 115 Effect of Solubility and Density of Organic Contaminants 123 Soluble Contaminants 123 x Contents and Subject Index Immiscible Flow 125 Fate of Organic Groundwater Pollutants 127 Overview 127 Equilibrium Partitioning of the Chemical 127 Degradation of the Chem ica I 127 Transport of the Chemical 127 Equilibrium Partitioning 130 Soil-Soil Water 130 Water-Soil Air 134 Soil-Soil Air 136 Degradation 138 Biodegradation 138 Hydrolysis 142 Transport. 146 Transport with Water 146 Volatilization and Vapor Transport 148 Diffusion 148 Sweep Flow 148 Barometric Pressure Pumping 148 Thermal Gradients 148 3. FIELD AND LABORATORY TECHNIQUES FOR ASSESSING GROUNDWATER CONTAMINATION 151 Drilling Methods 151 Auger Boring 151 Cable-Tool Percussion Drilling 158 Hydraulic Rotary Drilling 159 Sampling 162 Monitoring Well Construction 162 Geophysical Techniques Applicable to Groundwater Investigations 171 Introduction _171 Surface Geophysical Survey Methods 174 Gravity Surveying 174 Magnetic Surveys 177 Electrical (Resistivity) Surveys 177 Electromagnetic (EM) Methods 182 Electrical Sounding Using Natural Sources 183 Metal Detectors 183 Ground Penetrating Radar 185 Seismic Profiling 186 New Techniques and Instruments 186 Borehole Geophysics 189 Monitoring Field Sampling and Analysis Methods of Groundwater Investigation 197 Sampling Considerations 197 Manual Sampling Equipment 200 Vacuum Collection Equipment 206 Pneumatic or Pressurized Collection Equipment 208 Contents and Subject Index xi Mechanical Pumping Systems 211 Gas Entrainment Systems 213 Vadose (Unsaturated) Zone Sampling Systems 215 Chemical Analysis 218 Sample Preparation 218 General Analytical Techniques 221 General Approach to Analytical Methods 223 Gas Chromatography (GC) 226 Combined Gas Chromatography-Mass Spectrometry (GC/MS) 227 High Performance Liquid Chromatography (HPLC) 228 Mass Spectrometry 230 Ion Chromatography (lC) 231 Atomic Emission Spectroscopy (AES) 231 Atomic Absorption Spectroscopy (AAS) 232 Total Organic Carbon (TOC) and Total Organic Halogens (TOH) .. 235 4. PREDICTION OF CONTAMINANT TRANSPORT 236 Physical, Chemical, and Biological Parameters and Constants Applicable to Organic Contaminants and Physical Systems of Concern 236 Overview 236 Characteristics of Initial Mixing 239 Mathematics of Dispersion, Diffusion, and Dilution 241 Introduction 241 Mechanical Mixing 243 Diffusion 243 Contaminant Transport Processes 244 Nonreactive Species in Homogeneous Media 245 Nonreactive Species in a Heterogeneous Media 248 Reliability of Predictive Methods 251 5. GROUNDWATER TREATMENT CONTROL AND CONTAINMENT METHODS 253 Groundwater-Treatment Methods 253 Introduction 253 Overview of Treatment Technologies 253 Process Treatment Trains 257 Treatment Technologies 257 Activated Sludge 260 Description 260 Operation Characteristics 260 Design Considerations 263 Carbon Adsorption 263 Technology Description 263 Operating Characteristics 265 Design Considerations 265 Ozonation/Ultraviolet 268 Technology Description 268 xii Contents and Subject Index Operating Characteristics 270 Design Considerations 270 Stripping 273 Technology Description 273 Operating Characteristics 273 Design Considerations 275 Reverse Osmosis/Wet Air Oxidation 275 Technology Description 275 Operating Characteristics 275 Design Considerations 278 Groundwater Control and Containment Methods 278 Introduction 278 Control and Containment Technologies 280 Impermeable Barriers 280 Description 280 Engineering Considerations 282 Groundwater Pumping 286 Leachate Collection 290 Engineering Considerations 291 Removal 294 Surface Water Control 295 6. INFORMATION SOURCES 302 Geologic Framework and Hydrologic System 302 Site Information 309 REFERENCES 313 BIBLIOGRAPHY 321 GLOSSARy 334 APPENDIX: COSTS ASSOCIATED WITH WASTE DISPOSAL SITE CLEANUP 338 Part III Emergency Response ACKNOWLEDGMENTS 346 1. INTRODUCTION 347 Scope and Limitations of This Manual. 347 Required User Background, Training, and Preparation 348 Format of the Manual 350 Caveat 350 2. OVERVIEW OF RAPID ASSESSMENT METHODOLOGY 351 Application Scenarios 351 Contents and Subject Index xiii Methodology Flowchart 352 Critical Compound and Site Characteristics 355 Critical Compound Characteristics 355 Contaminant Identity 355 Extent of the Contamination 355 Solubility 357 Adsorption 357 Degradation 357 Toxicity 358 Concentration and Release/Loading Rate 358 Density, Viscosity, and Temperature 358 Critical Site Characteristics 358 Identity of Subsurface Medium (Unsaturated and Saturated Zones) 358 Age of the Site (Unsaturated and Saturated Zones) 359 Distances (Unsaturated and Saturated Zones) 359 Porosity 359 Infiltration, Net Recharge, and Volumetric Water Content (Unsaturated Zone Only) 359 Bulk Density (Unsaturated and Saturated Zones) 360 Hydraulic Conductivity (Saturated Zone) 360 Chemical Characteristics of Medium (Unsaturated and Saturated Zones) 360 Dispersion (Unsaturated and Saturated Zones) 361 Depth to Ground Water (Unsaturated Zone) 361 Hydraulic Gradient (Saturated Zone) 361 Effective Aquifer Thickness (Saturated Zone) 361 Structural & Geologic Features (Unsaturated & Saturated Zones) 362 Auxiliary Sources of Information 362 Sources of Compound Characterization Information 362 Records 363 Onsite Observations 363 Analyses 364 Handbooks and Data Bases 364 Experts 366 Sources of Site Characterization Information 368 Prior Studies 368 Textbooks 368 Well Owners 369 Records 369 Experts 369 Onsite Observations 369 3. RAPID ASSESSMENT NOMOGRAPH AND ITS USE 371 Development of the Assessment Nomograph 371 Contaminant Fate and Transport in Soils 372 Continuous and Pulse Contaminant Inputs and Associated Responses 374 xiv Contents and Subject Index Requ ired Parameters 375 The Nomograph and How to Use It 379 Worksheet Procedures for Continuous Input Assessment 381 Worksheet Procedures for Pulse Input Assessment 385 Linkage of Unsaturated and Saturated Zone Assessments 387 Assumptions, Limitations, and Parameter Sensitivity 389 Methodology Assumptions 389 Limitations and Parameter Sensitivity 392 4. PARAMETER ESTIMATION GUIDELINES 394 General Parameter Estimation 395 Identity of Contaminants 395 Contaminant Concentration 396 Chemical Loss Mechanisms 398 Volatilization-Method 1 399 Method 2 400 Method 3 401 Nature of Soils and Geological Strata 402 Age of the Waste Site or Spill. 403 Depth to Ground Water 403 Unsaturated Zone Parameter Estimation 404 Pore Water Velocity 404 Percolation/Recharge 406 Volumetric Water Content 416 Total and Effective Porosity 417 Degradation Rate ' 417 Retardation Factor 424 Partition Coefficient 424 Organic Carbon/Organic Matter Content 425 Retardation Factors for Ionic Species 427 Acids and Bases in Solution 430 Retardation Factor for Acids and Bases 431 Bulk Density 436 Dispersion Coefficient 436 Saturated Zone Parameter Estimation 437 Effective Aquifer Thickness (or Zone of Mixing) 437 Ground-Water (Interstitial Pore Water) Velocity 440 Hydraulic Conductivity 440 Ground-Water Flow Gradient 441 Dispersion Coefficient 441 Retardation Factor 444 Degradation/Decay Rate 446 Source Contam inant Concentration 446 5. EXAMPLE APPLICATIONS AND RESULT INTERPRETATION 447 Example #1: Assessment of a Continuous Contaminant Source 447 Evaluation of Profile Responses 448 Evaluation of Time Response at the Ground-Water Table 448 Contents and Subject Index xv Evaluation of Time Response in Ground Water 448 Example #2: Assessment of a Pulse Contaminant Source 455 REFERENCES 468 APPENDIX A: U.S. SOIL CONSERVATION SERVICE RUNOFF ESTIMATION PER 10D 473 APPENDIX B: GLOSSARY 479 APPENDIX C: WORKSHEETS AND ENLARGED NOMOGRAPHS FOR RAPID ASSESSMENT PROCEDURES 485 ADDENDUM 489