List of colour plates .......................................... xi
List of boxes ................................................. xiv
Preface to the second edition ................................. xvi
Preface to the first edition ................................. xvii
Acknowledgements ............................................ xviii
Symbols and abbreviations ..................................... xix
About the companion website ................................. xxiii
1 Introduction ............................................... 1
1.1 Scope of this book ......................................... 1
1.2 What is hydrogeology? ...................................... 2
1.3 Early examples of groundwater exploitation ................. 3
1.4 History of hydrogeology .................................... 5
1.5 The water cycle ........................................... 10
1.6 Groundwater as a natural resource ......................... 12
1.7 Management and protection of groundwater resources in
the United Kingdom ........................................ 20
1.8 European Union Water Framework Directive .................. 21
1.9 Management and protection of groundwater resources in
the United States ......................................... 22
1.10 Groundwater resources in developing countries ............. 23
1.11 Future challenges for groundwater management .............. 25
Further reading ........................................... 26
References ................................................ 26
2 Physical hydrogeology ..................................... 29
2.1 Introduction .............................................. 29
2.2 Porosity .................................................. 29
2.3 Hydraulic conductivity .................................... 31
2.4 Isotropy and homogeneity .................................. 33
2.5 Aquifers, aquitards and aquicludes ........................ 33
2.6 Darcy's Law ............................................... 35
2.6.1 Hydraulic properties of fractured rocks ............ 38
2.6.2 Karst aquifer properties ........................... 41
2.7 Groundwater potential and hydraulic head .................. 43
2.8 Interpretation of hydraulic head and groundwater
conditions ................................................ 44
2.8.1 Groundwater flow direction ......................... 44
2.8.2 Water table and Potentiometrie surface maps ........ 46
2.8.3 Types of groundwater conditions .................... 53
2.8.1 Transmissivity and storativity of confined
aquifers ........................................... 57
2.9.1 Release of water from confined aquifers ............ 58
2.10 Transmissivity and specific yield of unconfined aquifers .. 66
2.11 Equations of groundwater flow ............................. 67
2.11.1 Steady-state saturated flow ........................ 67
2.11.2 Transient saturated flow ........................... 68
2.11.3 Transient unsaturated flow ......................... 68
2.12 Analytical solution of one-dimensional groundwater flow
problems .................................................. 69
2.13 Groundwater flow patterns ................................. 74
2.14 Classification of springs and intermittent streams ........ 81
2.15 Transboundary aquifer systems ............................. 86
2.16 Submarine groundwater discharge ........................... 92
2.17 Groundwater resources of the world ........................ 97
2.18 Hydrogeological environments of the United Kingdom ........ 99
2.18.1 Sedimentary rocks .................................. 99
2.18.2 Metamorphic rocks ................................. 104
2.18.3 Igneous rocks ..................................... 105
Further reading .......................................... 105
References ............................................... 105
3 Groundwater and geological processes ..................... 109
3.1 Introduction ............................................. 109
3.2 Geological processes driving fluid flow .................. 109
3.3 Topography-driven flow in the context of geological
processes ................................................ 110
3.4 Compaction-driven fluid flow ............................. 110
3.5 Variable-density driven fluid flow ....................... 114
3.5.1 Salinity gradients leading to variable-density
flow .............................................. 114
3.5.2 Hydrothermal systems driven by variable-density
flow .............................................. 119
3.6 Regional groundwater flow systems driven predominantly
by variable-density flow ................................. 120
3.6.1 Fluctuating sea-level and its impact on the
distribution of groundwater salinity in coastal
areas ............................................. 120
3.6.2 Brines in continental aquifers .................... 126
3.7 Regional groundwater flow systems driven predominantly
by shifting topography and stress changes ................ 126
3.7.1 Mountain building and erosion ..................... 127
3.7.2 Impact of glaciations on regional hydrogeology .... 127
3.8 Coupling and relative importance of processes driving
fluid flow ............................................... 133
Further reading .......................................... 133
References ............................................... 134
4 Chemical hydrogeology .................................... 135
4.1 Introduction ............................................. 135
4.2 Properties of water ...................................... 135
4.3 Chemical composition of groundwater ...................... 137
4.4 Sequence of hydrochemical evolution of groundwater ....... 139
4.5 Groundwater sampling and graphical presentation of
hydrochemical data ....................................... 140
4.6 Concept of chemical equilibrium .......................... 151
4.6.1 Kinetic approach to chemical equilibrium .......... 151
4.6.2 Energetic approach to chemical equilibrium ........ 152
4.7 Carbonate chemistry of groundwater ....................... 154
4.8 Adsorption and ion exchange .............................. 165
4.9 Redox chemistry .......................................... 172
4.10 Groundwater in crystalline rocks, 181 Further reading .... 188
References ............................................... 188
5 Environmental isotope hydrogeology ....................... 191
5.1 Introduction ............................................. 191
5.2 Stable isotope chemistry and nomenclature ................ 191
5.3 Stable isotopes of water ................................. 192
5.4 Age dating of groundwater ................................ 198
5.4.1 Law of radioactive decay .......................... 198
5.4.2 14C dating ........................................ 198
5.4.3 36Cl dating ....................................... 202
5.4.4 Tritium dating .................................... 202
5.4.5 3H/3He dating ..................................... 205
5.5 Noble gases .............................................. 206
Further reading .......................................... 209
References ............................................... 209
6 Groundwater and catchment processes ...................... 211
6.1 Introduction ............................................. 211
6.2 Water balance equation ................................... 211
6.3 Precipitation and evapotranspiration ..................... 213
6.3.1 Precipitation measurement ......................... 213
6.3.2 Evapotranspiration measurement and estimation ..... 215
6.4 Soil water and infiltration .............................. 219
6.4.1 Soil moisture content and soil water potential .... 219
6.4.2 Calculation of drainage and evaporation losses .... 223
6.4.3 Infiltration theory and measurement ............... 225
6.5 Recharge estimation ...................................... 227
6.5.1 Borehole hydrograph method ........................ 228
6.5.2 Soil moisture budget method ....................... 228
6.5.3 Chloride budget method ............................ 230
6.5.4 Temperature profile method ........................ 230
6.6 Stream gauging techniques ................................ 233
6.6.1 Velocity area methods ............................. 237
6.6.1.1 Surface floats ........................... 237
6.6.1.2 Current metering ......................... 238
6.6.1.3 Acoustic Doppler current profiler ........ 239
6.6.2 Dilution gauging .................................. 242
6.6.3 Ultrasonic, electromagnetic and integrating
float methods ..................................... 243
6.6.4 Slope-area method ................................. 244
6.6.5 Weirs and flumes .................................. 245
6.7 Hydrograph analysis ...................................... 246
6.7.1 Quickflow and baseflow separation ................. 247
6.7.2 Unit hydrograph theory ............................ 249
6.8 Surface water - groundwater interaction .................. 253
6.8.1 Temperature-based methods of detection ............ 256
6.8.2 Simulating river flow depletion ................... 257
6.8.2.1 Analytical solutions ..................... 257
6.8.2.2 Catchment resource modelling ............. 258
Further reading .......................................... 262
References ............................................... 262
7 Groundwater investigation techniques ..................... 265
7.1 Introduction ............................................. 265
7.2 Measurement and interpretation of groundwater level
data ..................................................... 265
7.2.1 Water level measurement ........................... 265
7.2.2 Well and borehole design and construction
methods ........................................... 266
7.2.3 Borehole hydrographs and barometric efficiency .... 268
7.2.4 Construction of groundwater level contour maps .... 272
7.3 Field estimation of aquifer properties ................... 272
7.3.1 Piezometer tests .................................. 272
7.3.2 Pumping tests ..................................... 273
7.3.2.1 Thiem equilibrium method ................. 275
7.3.2.2 Theis non-equilibrium method ............. 276
7.3.2.3 Cooper-Jacob straight-line method ........ 277
7.3.2.4 Recovery test method ..................... 282
7.3.2.5 Principle of superposition of drawdown ... 283
7.3.2.6 Leaky, unconfined and bounded aquifer
systems .................................. 284
7.3.3 Tracer tests ...................................... 287
7.3.4 Geophysical methods ............................... 292
7.4 Remote sensing methods ................................... 295
7.5 Groundwater modelling .................................... 298
Further reading .......................................... 301
References ............................................... 301
8 Groundwater quality and contaminant hydrogeology ......... 304
8.1 Introduction ............................................. 304
8.2 Water quality standards .................................. 304
8.2.1 Water hardness .................................... 306
8.2.2 Irrigation water quality .......................... 309
8.3 Transport of contaminants in groundwater ................. 311
8.3.1 Transport of non-reactive dissolved contaminants .. 311
8.3.1.1 One-dimensional solute transport
equation ................................. 314
8.3.2 Transport of reactive dissolved contaminants ...... 315
8.3.3 Transport of non-aqueous phase liquids ............ 327
8.3.3.1 Hydrophobic sorption of non-polar
organic compounds ........................ 329
8.3.4 Effects of density and heterogeneity .............. 333
8.4 Sources of groundwater contamination ..................... 334
8.4.1 Urban and industrial contaminants ................. 334
8.4.2 Municipal landfill, domestic and cemetery wastes .. 343
8.4.3 Agricultural contaminants ......................... 350
8.4.4 Saline water intrusion in coastal aquifers ........ 356
Further reading ................................... 362
References ............................................... 362
9 Groundwater pollution remediation and protection ......... 366
9.1 Introduction ............................................. 366
9.2 Groundwater pollution remediation techniques ............. 366
9.2.1 Pump-and-treat .................................... 367
9.2.2 Permeable reactive barriers ....................... 372
9.2.3 Monitored natural attenuation ..................... 373
9.3 Groundwater pollution protection strategies in
industrialized countries ................................. 379
9.3.1 Groundwater vulnerability mapping and aquifer
resource protection ............................... 379
9.3.2 Source protection zones ........................... 380
9.3.3 Risk assessment methods ........................... 386
9.3.4 Spatial planning and groundwater protection ....... 387
9.4 Groundwater protection strategies in developing
countries ................................................ 392
Further reading .......................................... 397
References ............................................... 397
10 Groundwater resources and environmental management ....... 400
10.1 Introduction ............................................. 400
10.2 Groundwater resources schemes ............................ 400
10.2.1 Large-scale groundwater development schemes ....... 400
10.2.2 Regional-scale groundwater development schemes .... 404
10.2.3 Artificial storage and recovery schemes ........... 406
10.2.4 Riverbank filtration schemes ...................... 410
10.2.5 Horizontal well schemes ........................... 416
10.2.1 Wetland hydrogeology .............................. 416
10.4 Climate change and groundwater resources ................. 424
10.4.1 Adaptation to climate change ...................... 435
Further reading .......................................... 440
References ............................................... 440
Appendices .................................................... 444
1 Conversion factors ......................................... 444
2 Properties of water in the range 0-100°C ................... 445
3 The geological timescale ................................... 446
4 Symbols, atomic numbers and atomic weights ................. 447
5 Composition of seawater and rainwater ...................... 449
References ................................................. 452
6 Values of W(u) for various values of u ..................... 453
7 Values of q/Q and v/Qt corresponding to selected values
of t/F for use in computing the rate and volume of stream
depletion by wells and boreholes ........................... 454
8 Complementary error function ............................... 455
9 Drinking water quality standards and Lists I and II
Substances ................................................. 456
10 Review questions and exercises ............................. 462
References ................................................. 504
Index ......................................................... 505
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