Environmental Modeling and Health Risk Analysis (Acts/Risk) (eBook)

Dr. Mustafa M. Aral is a Professor and the Director of Multimedia Environmental Simulations Laboratory, a research center at the School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta,Georgia, USA. He received his B.S. degree in Civil Engineering from Middle East Technical University, Ankara, Turkey, and M.S. and Ph.D. degrees from School of Civil and Environmental Engineering, Georgia Institute of Technology. His specialization area is in the fields ofenvironmental modeling, water resources engineering, mathematical, numerical and optimization methods, exposure and health risk analysis. He is a registered professional engineer in the State of Georgia with more than 35 years of research and consulting experience in environmental quality and quantity modeling, environmental fluid mechanics, optimal management of engineered and environmental systems, site characterization and health risk assessment studies. Dr. Aral has authored and co-authored more than 300 technical publications and reports. He serves as the Editor of the International Journal on Water Quality, Exposure and Healthpublished by Springer publishers and he is also an Associate Editor of several other technical journals in water resources and environmental engineering. His research work and publications has received numerous technical awards in publication excellence and research development categories from several state and federal agencies, and professional organizations. He is the principal author and developer of the ACTS and RISK software that is used in this book.

Preface 6
Environmental Modeling and Health Risk Analysis (ACTS/RISK) 6
Author 8
Acknowledgements 10
Contents 12
Chapter 1: Introduction 16
1.1 Environmental Processes 26
1.2 Environmental Modeling Concepts 31
1.3 Environmental Toxicology 35
1.4 Exposure Analysis 37
1.5 Environmental Risk Analysis 38
1.6 Environmental Epidemiology 43
1.7 The ACTS and RISK Software 43
1.8 Outline 48
References 49
Chapter 2: Principles of Environmental Modeling 52
2.1 Modeling Principles 55
2.2 Model Building and Model Types 56
2.3 Model Calibration, Validation, Verification and Sensitivity Analysis 60
2.4 Model Scales, Error and Uncertainty 65
2.5 Methods of Solution 73
2.6 Modeling Terminology 74
References 74
Chapter 3: Conservation Principles, and Environmental Transformation and Transport 77
3.1 Transport Principles 81
3.2 Conservation Principles 87
3.3 Sources and Sinks 94
3.4 Reactions 96
3.5 Boundary and Initial Conditions 105
3.6 Multi-pathway and Inter-pathway Mass Transport 107
References 107
Chapter 4: Air Pathway Analysis 109
4.1 Lapse Rate and Atmospheric Stability 112
4.2 Principles of Atmospheric Stability 114
4.3 Air Pathway Models 121
4.4 Air Emission Models 126
4.4.1 Farmers Model 127
4.4.2 Thibodeaux-Hwang Model 131
4.4.3 Cowherd Particulate Emission Model 134
4.4.4 Jury Unsaturated Zone Emission Model 138
4.4.5 Landfill Gas Emissions Model 141
4.4.6 Volatilization from Water Bodies 144
4.4.7 Air Dispersion Models 148
4.4.8 Box Air Dispersion Model 150
4.4.9 Gaussian Air Dispersion Models 152
4.4.9.1 Steady State Air Dispersion Models 152
4.4.9.2 Unsteady State Air Dispersion Models 161
4.4.10 Air Dispersion Model Assumptions and Limitations 162
4.4.11 Indoor Air Dispersion Models 163
4.4.12 Vapor Concentration at the Contamination Source 166
4.4.13 Diffusion Through the Capillary Zone 168
4.4.14 Diffusion Through the Unsaturated Zone 169
4.4.15 Building Ventilation Rate and Volumetric Flow Rate 170
4.4.16 Soil Contamination with a Residual Phase 171
4.4.17 Parameter Uncertainty Analysis 173
4.5 ``Chemicals´´ Database 176
4.6 Applications 177
References 198
Chapter 5: Groundwater Pathway Analysis 201
5.1 Definitions and Governing Principles 201
5.2 Groundwater Pathway Models 212
5.3 Saturated Constant Dispersion Coefficient Contaminant Transport Models 216
5.3.1 One-Dimensional Contaminant Transport Models with Constant Dispersion Coefficient 216
5.3.1.1 Finite Aquifer with a Dirichlet Boundary Condition 220
5.3.1.2 Finite Aquifer with a Cauchy Boundary Condition 221
5.3.1.3 Semi-infinite Aquifer with a Dirichlet Boundary Condition 222
5.3.1.4 Semi-infinite Aquifer with a Cauchy Boundary Condition 223
5.3.2 Two-Dimensional Contaminant Transport Models with Constant Dispersion Coefficient 224
5.3.2.1 Finite Width Source in Finite and Infinite Aquifers 226
5.3.2.2 Infinite Aquifer with a Gaussian Boundary Condition 228
5.3.2.3 Infinite Aquifer with a Point Source Boundary Condition 230
5.3.3 Three-Dimensional Contaminant Transport Models with Constant Dispersion Coefficient 232
5.3.3.1 Infinite Aquifer with a Point Source Boundary Condition 234
5.3.3.2 Finite Aquifer with a Finite Patch Contaminant Source Boundary Condition 235
5.3.3.3 Infinite Aquifer with a Finite Patch Contaminant Source Boundary Condition 236
5.4 Multi-species Biodegradation By-Product Models 239
5.5 Saturated Variable Dispersion Coefficient Groundwater Pathway Models 245
5.5.1 Mathematical Models for Variable Dispersion Coefficients 246
5.5.2 Solution for Instantaneous Point Injection of a Contaminant into an Initially Uncontaminated Aquifer 250
5.5.3 Solution for a Continuous Point Source in an Initially Uncontaminated Aquifer 252
5.5.4 Initial Point Concentration Distribution in an Aquifer Without Injection 254
5.5.5 Line Initial Concentration Distribution Without Injection 255
5.5.6 Analytical Solutions for an Instantaneous Line Injection into an Initially Uncontaminated Aquifer 257
5.5.7 Analytical Solutions for a Continuous Line Source for an Initially Uncontaminated Aquifer 258
5.5.8 Numerical Examples for Variable Dispersion Coefficient Models 260
5.6 Unsaturated Groundwater Pathway Models 268
5.6.1 Marino Model 268
5.6.2 Jury Model 271
5.7 Applications 273
References 287
Chapter 6: Surface Water Pathway Analysis 289
6.1 Definitions and Governing Principles 292
6.1.1 Uniform Flow in Open Channels 294
6.1.2 Mixing Models in Open Channels 297
6.1.3 Elementary Transport Models in the Aquatic Pathway 300
6.1.4 Elementary Transport Models for Small Lakes and Impoundments 304
6.2 Surface Water Pathway Models 305
6.3 Near Field Mixing Models 309
6.3.1 Surface-Point Discharges 311
6.3.1.1 Stagnant and Weak Cross-Currents 312
6.3.2 Submerged-Point Discharges 314
6.3.2.1 Stagnant or Weak Cross-Currents 316
6.3.3 Submerged Multiport Diffusers 318
6.3.3.1 Deep Receiving Water 319
6.3.3.2 Shallow Receiving Water 320
6.4 Far Field Mixing Models 321
6.4.1 Mixing in Rivers 322
6.4.1.1 Transverse Mixing in Rivers 322
6.4.1.2 Longitudinal Advection and Dispersion 325
6.4.2 Estuaries 327
6.4.3 Small Lakes and Reservoirs 328
6.4.4 Oceans and Great Lakes 328
6.5 Surface Water Sediments 330
6.5.1 River Bed Sediments 331
6.5.2 Estuary Sediments 334
6.5.3 Coastal Waters and Ocean Sediments 336
6.5.4 Lake Sediments 336
6.6 Applications 338
References 344
Chapter 7: Uncertainty and Variability Analysis 347
7.1 Probability Theory and Probability Distribution Functions 350
7.2 Probability Density Functions 355
7.3 Monte Carlo Analysis 362
7.4 Interpretation of the Results of the Monte Carlo Analysis 363
7.5 When an Uncertainty Analysis Will be Useful and Necessary 366
References 368
Chapter 8: Health Risk Analysis 370
8.1 USEPA Guidelines on Baseline Health Risk Assessment 371
8.2 Exposure Intake Models 377
8.2.1 Intake Model for Ingestion of Drinking Water 379
8.2.2 Intake Model for Ingestion while Swimming 379
8.2.3 Intake Model for Dermal Intake 380
8.2.4 Intake Model for Intake Via Soil, Sediment or Dust 381
8.2.5 Intake Model for Dermal Absorption of Soil, Sediment and Dust 381
8.2.6 Intake Model for Air Intakes 381
8.2.7 Intake Model for Ingestion of Fish and Shellfish 382
8.2.8 Intake Model for Ingestion of Vegetables and other Produce 382
8.2.9 Intake Model for Ingestion of Meat, Eggs and Dairy Products 382
8.3 Applications 382
References 389
Chapter 9: Application: Pesticide Transport in Shallow Groundwater and Environmental Risk Assessment 391
9.1 Problem Description 392
9.2 Background on Site and Contamination Conditions 393
9.2.1 Health and Regulatory Considerations 393
9.2.2 Site Geology and Hydrogeology 397
9.2.3 Chemical and Contaminant Properties of BHC 397
9.3 Method of Analysis 398
9.3.1 Modeling Approach and Assumptions 398
9.3.2 Model Input Parameters and Source Definition for Deterministic Simulations 399
9.3.3 Model Input Parameters for Probabilistic Simulations 404
9.4 Modeling Results 406
9.4.1 Deterministic Model Simulations 407
9.4.2 Probabilistic Model Simulations 408
9.5 Discussion of Results and Conclusions 413
9.6 Limitations 415
9.7 Practical Applications 416
References 417
Appendix 1: Definitions of Acronyms and Abbreviations 420
Appendix 2: Environmental Modeling and Exposure Analysis Terms 427
Environmental Pathways and Processes 427
Environmental Modeling 430
Environmental Toxicology 435
Exposure Analysis 437
Environmental Risk Analysis 443
Environmental Epidemiology 447
Appendix 3: Definitions and Operations of the ACTS/RISK Software 449
Contributors to the ACTS/RISK Software 449
ACTS and RISK Software Download 450
Disclaimer 450
Background Information 450
Overview of the Computational Platform 451
Preferences Menu 453
Menu Definitions and Operations of the ACTS Software 455
Standard Menu Options and Operations 455
File Menu 455
Calculate Menu 456
Results Menu 456
Special Menu (Only in AIR Pathway Model) 457
Help Menu 457
Chemical Menu Options 458
Monte Carlo Module of the ACTS/RISK Software 459
Display of Results in the GRAPHIX Module 461
Description of Menu Options in the Monte Carlo Simulation Window 462
File Menu: Same as Before 462
Graphics Module of the ACTS/RISK Software 462
Rules for Data Entry in a Typical Input Window 467
Appendix 4: MCL Levels on Contaminants 468
Appendix 5: Conversion Tables and Properties of Water 471
Index 473