Mine Wastes (eBook)

Preface 5
Contents 7
Glossary 12
1 Introduction to Mine Wastes 14
1.1 Scope of the Book 14
1.2 Definitions 16
1.2.1 Mining Activities 16
1.2.2 Metals, Ores and Industrial Minerals 16
1.2.3 Mine Wastes 17
1.3 Mine Waste Production 22
1.4 Mine Wastes: Unwanted By-Products or Valuable Resources? 25
Scientific Issue 1.1. Historical Base Metal Smelting Slags 26
The Principles of Smelting 26
Slags of Lavrion, Greece 27
Potential Recycling 27
1.5 Mining and Environmental Impacts 28
Scientific Issue 1.2. Geology and its Influence on the Environmental Impacts of Mineral Deposits 29
The Environmental Geology of Mineral Deposits 29
The Environmental Geology of Gold Deposits, New Zealand 30
Scientific Issue 1.3. The Debate on Mining and Its Environmental Impacts 31
Issue 1 -- Land Disturbance 31
Critics of the Mining Industry 31
The Mining Industry 31
Issue 2 -- Waste Production 31
Critics of the Mining Industry 31
The Mining Industry 32
Issue 3 -- Recycling Rather Than Mining 32
Critics of the Mining Industry 32
The Mining Industry 32
Issue 4 -- Pollution 32
Critics of the Mining Industry 32
The Mining Industry 32
Issue 5 -- Heavy Metal Release 33
Critics of the Mining Industry 33
The Mining Industry 33
Issue 6 -- Environmental Damage 34
Critics of the Mining Industry 34
The Mining Industry 34
1.5.1 Contamination and Pollution 34
1.5.2 Historic Mining 35
Case Study 1.1. Historic Mining in Australia and Its Environmental Impacts 37
Introduction 37
Environmental Impacts of Historic Mines 38
Early Rehabilitation at Historic Mines 39
Conclusions 40
1.5.3 Present-Day Unregulated Mining 41
Case Study 1.2. Mercury Pollution and Gold Mining in the Brazilian Amazon 42
Agglutination and Amalgamation 42
Mercury Release to the Amazon Environment 43
1.5.4 Regulation of Modern Mining 44
1.6 Rehabilitation of Mine Wastes and Mine Sites 46
Case Study 1.3. Sudbury, Canada: From Pollution Record Holder to Award Winning Restoration Site 47
Mining and Smelting 47
Pollution and Degradation 47
Rehabilitation 48
1.7 Sources of Information 51
1.8 Summary 53
2 Sulfidic Mine Wastes 55
2.1 Introduction 55
Scientific Issue 2.1. Early Historical Observations on Sulfide Oxidation and Acid Mine Drainage 55
Early Scholars 55
Diego Delgado (1556) 56
2.2 Weathering of Sulfidic Mine Wastes 57
2.3 Acid Producing Reactions 58
2.3.1 Pyrite 58
Scientific Issue 2.2. Pyrite Oxidation in Permafrost Regions 65
Permafrost 65
Pyrite Oxidation at Low Temperatures 65
Tailings Disposal in Permafrost Regions 66
2.3.2 Other Sulfides 69
2.3.3 Other Minerals 71
2.4 Acid Buffering Reactions 72
2.4.1 Silicates 73
2.4.2 Carbonates 75
2.4.3 Exchangeable Cations 76
2.4.4 Reaction Rates 76
2.5 Coal Mine Wastes 78
2.5.1 Spontaneous Combustion of Pyritic Wastes 80
2.6 Formation and Dissolution of Secondary Minerals 82
2.6.1 Pre-mining and Post-mining Secondary Minerals 82
2.6.2 Solubility of Secondary Minerals 88
2.6.3 Acid Consumption and Production 89
2.6.4 Coatings and Hardpans 90
2.7 Acid Generation Prediction 92
2.7.1 Geological Modeling 92
2.7.2 Geological, Petrographic, Geochemical and Mineralogical Descriptions 93
2.7.3 Sampling 94
2.7.4 Geochemical Tests 95
2.7.4.1 Static Tests 95
2.7.4.2 Kinetic Tests 101
2.7.5 Modeling the Oxidation of Sulfidic Waste Dumps 103
2.8 Monitoring Sulfidic Wastes 104
2.9 Environmental Impacts 106
2.9.1 Soil and Sediment Contamination 107
Case Study 2.1. Sulfidic Mine Wastes and Their Environmental Impacts at Historical Metalliferous Mine Sites in the New England Area, Australia 108
Introduction 108
Sulfidic Ore and Waste Dumps 109
Drainage Systems 109
Soils 109
Vegetation and Algae 110
Pollution 110
Scientific Issue 2.3. Trace Metal Release from Historical Smelting Slags 111
Characteristics of Smelting Slags 111
Weathering of Slags 111
Plant Colonization 113
2.10 Control of Sulfide Oxidation 114
Scientific Issue 2.4. Coating Technologies for Sulfidic Wastes 115
Coating Technologies 115
Phosphate Stabilization 115
2.10.1 Wet Covers 117
2.10.2 Dry Covers 118
2.10.2.1 Unsaturated Covers 120
2.10.2.2 Saturated Covers 121
2.10.2.3 Store-and-Release Covers 122
2.10.3 Encapsulation, In-Pit Disposal and Mixing mixing 123
2.10.4 Co-disposal and Blending 124
2.10.5 Addition of Organic Wastes 125
2.10.6 Bactericides 126
2.11 Summary 127
3 Mine Water 130
3.1 Introduction 130
Case Study 3.1. Acid Mine Drainage at the Rio Tinto Mines, Spain 131
The Iberian Pyrite Belt 131
The Rio Tinto Mining District 131
The Tinto River 132
3.2 Sources of AMD see acid mine drainage acid , mine drainage (AMD) 133
3.3 Characterization 136
3.3.1 Sampling and Analysis 137
3.4 Classification 139
3.4.1 Acid Waters 141
3.4.2 Extremely Acid Waters 143
3.4.3 Neutral to Alkaline Waters 143
3.4.4 Coal Mine Waters 144
3.5 Processes 144
3.5.1 Microbiological Activity 145
3.5.2 Precipitation and Dissolution of Secondary Minerals 147
3.5.3 Coprecipitation 152
3.5.4 Adsorption and Desorption 152
3.5.5 Eh-pH Conditions 154
3.5.6 Heavy Metals 155
3.5.7 The Iron System 157
3.5.8 The Aluminium System 161
3.5.9 The Arsenic System 163
3.5.10 The Mercury System 165
3.5.11 The Sulfate System 165
3.5.12 The Carbonate System 167
3.5.13 pH Buffering 168
3.5.14 Turbidity 170
3.6 Prediction of Mine Water Composition 170
3.6.1 Geological Modeling 170
3.6.2 Mathematical and Computational Modeling 171
3.7 Field Indicators of AMD 173
3.8 Monitoring AMD 173
Scientific Issue 3.1. Seasonal and Diel Factors Controlling Water Composition. 174
Seasonal Factors 174
Diel Factors 174
Scientific Issue 3.2. Acid Pit Lakes 178
Formation of Pit Lakes 178
General Characteristics of Pit Lakes 178
Acid Pit Lakes 179
3.9 AMD from Sulfidic Waste Rock Dumps 180
3.9.1 Hydrology of Waste Rock Dumps 181
3.9.2 Weathering of Waste Rock Dumps 182
3.9.3 Temporal Changes to Dump Seepages 184
3.10 Environmental Impacts 185
3.10.1 Surface Water Contamination 186
3.10.2 Impact on Aquatic Life 187
3.10.3 Sediment Contamination 187
3.10.4 Ground Water Contamination 188
3.10.5 Climate Change 190
3.11 AMD Management Strategies 190
3.12 Treatment of AMD 191
Scientific Issue 3.3. The Use of Red Mud from Bauxite Refineries to Treat AMD 193
Production of Bauxite Refinery Waste 193
Use of Bauxite Refinery Waste 194
3.12.1 Active Neutralization 197
3.12.2 Other Chemical Treatments 200
3.13 Summary 212
4 Tailings 215
4.1 Introduction 215
4.2 Tailings Characteristics 216
4.2.1 Process Chemicals 216
4.2.2 Tailings Liquids 218
4.2.3 Tailings Solids 218
4.3 Tailings Dams 220
4.3.1 Tailings Hydrogeology 222
4.3.2 AMD Generation 224
4.3.3 Tailings Dam Failures 227
4.3.4 Monitoring 234
4.3.5 Wet and Dry Covers 235
4.4 Thickened Discharge and Paste Technologies 236
4.5 Backfilling 237
4.6 Riverine and Lacustrine Disposal 239
Case Study 4.1. Riverine Tailings Disposal at Ok Tedi, Papua New Guinea 242
The Ok Tedi Mine 242
Discharge of Waste into Ok Tedi River 242
4.7 Marine Disposal 243
Case Study 4.2. Submarine Tailings Disposal at the Black Angel Mine, Greenland. 244
The Black Angel Lead-Zinc Mine 244
Tailings Discharge 244
Transfer of Metals into the Fjord 246
4.8 Recycling and Reuse 247
Scientific Issue 4.1. Phytoremediation and Phytomining of Metalliferous Wastes 247
Introduction 247
Phytoremediation 247
Phytomining 248
4.9 Summary 249
5 Cyanidation Wastes of Gold-Silver Ores 252
5.1 Introduction 252
5.2 Occurrences and Uses of Cyanide 252
5.3 Cyanide Chemistry 254
5.3.1 Free Cyanide 255
5.3.2 Simple Cyanide Compounds 256
5.3.3 Complexed Cyanide 256
5.4 Gold Extraction 257
5.4.1 Heap Leach Process 257
5.4.2 Vat/Tank Leach Process 258
5.5 Hydrometallurgical Wastes 259
5.6 Cyanide Analysis and Monitoring 260
5.7 Environmental Impacts 261
Case Study 5.1. Cyanide Spill at Baia Mare, Romania 262
Mining History 262
Tailings Dam Failure 262
Recovery 263
5.8 Cyanide Destruction 265
5.8.1 Natural Attenuation 266
5.8.2 Enhanced Natural Attenuation 268
5.8.3 Engineered Attentuation 269
5.9 Summary 270
6 Radioactive Wastes of Uranium Ores 272
6.1 Introduction 272
6.2 Mineralogy and Geochemistry of Uranium 272
6.2.1 Uranium Ores 272
6.2.2 Placer and Beach Sands 273
6.3 Aqueous Chemistry of Uranium 274
6.3.1 Oxidative Dissolution of Uranium Minerals 274
6.3.2 Uranium Solubility 276
6.3.3 Uranium Precipitation 277
6.4 Radioactivity 278
6.4.1 Principles of Radioactivity 278
6.4.2 Radioactive Decay of Uranium and Thorium 279
6.4.2.1 Radium 281
6.4.2.2 Radon 281
6.4.3 Units and Measurements of Radioactivity and Radiation Dose 282
6.4.3.1 Units 282
6.4.3.2 Measurements 284
6.4.4 Radioactive Equilibrium and Disequilibrium 284
6.5 Uranium Mining and Extraction 285
6.5.1 Conventional Mining and Extraction 286
6.5.2 In Situ Leach (ISL) Operations 287
Case Study 6.1. Waste Production and Environmental Impacts of the Wismut Uranium Mines, Germany 289
Mining 289
Environmental Impacts and Rehabilitation 290
Waste Production 290
ISL Operations 291
Conclusions 291
6.6 Mining, Processing and Hydrometallurgical Wastes 292
6.7 Tailings 293
6.7.1 Tailings Radioactivity 293
6.7.2 Tailings Solids 294
6.7.3 Tailings Liquids 296
6.7.4 Tailings Disposal 297
6.7.5 Long-Term Stability of Tailings Dams 299
6.8 Mine Water 301
6.8.1 Constituents 301
6.8.2 Treatment 302
6.9 Monitoring 304
6.10 Radiation Hazards 305
6.10.1 Radiation Dose and Human Health 306
6.10.2 Occupational Radiation Exposure 307
6.11 Environmental Impacts 310
Case Study 6.2. Environmental Review of the Rehabilitated Mary Kathleen Uranium Mine, Australia 311
Mining and Rehabilitation at Mary Kathleen 311
Open Pit 312
Waste Rock Piles 312
Tailings Dam 312
Drainage 313
Conclusions 313
6.11.1 Excessive Radioactivity Levels and Radon Emissions 314
6.11.2 Inappropriate Use of Tailings and Waste Rocks 315
6.11.3 Failure of Tailings Dams 315
6.11.4 Soil and Sediment Contamination 315
Case Study 6.3. Environmental Review of the Rehabilitated Radium Hill Uranium Mine, South Australia 316
Introduction 316
The Radium Hill Mine 316
Physical Dispersion 317
6.11.5 Ground and Surface Water Contamination 317
6.11.6 Acid Mine Drainage 318
6.12 Summary 318
7 Wastes of Phosphate and Potash Ores 322
7.1 Introduction 322
7.2 Potash Mine Wastes 322
7.2.1 Potash Ores 323
7.2.2 Mining and Processing Wastes 323
7.3 Phosphate Mine Wastes 324
7.3.1 Phosphate Rock 324
7.3.1.1 Mineralogy and Geochemistry 326
7.3.2 Mining, Processing and Hydrometallurgical Wastes 326
7.3.3 Phosphogypsum 329
7.3.3.1 Mineralogy and Geochemistry 329
7.3.3.2 Radiochemistry 332
7.3.4 Disposal of Phosphogypsum 332
7.3.4.1 Riverine and Marine Disposal 333
7.3.4.2 Backfilling 333
7.3.4.3 Phosphogypsum Stacks 334
7.3.4.4 Recycling 336
Scientific Issue 7.1. Recovery of Trace Constituents from Phosphate Rock 336
Resources within Phosphate Rock 336
Recovery of Elements 337
7.3.5 Potential Hazards and Environmental Impacts 338
7.3.5.1 Phosphogypsum 338
7.3.5.2 Waste Rocks and Tailings 340
7.4 Summary 341
References 343
Index 401