Contenido Guidelines for Evaluating Water in Pit Slope Stability

Guidelines for Evaluating Water in Pit Slope Stability is a comprehensive account of the hydrogeological procedures that should be followed when performing open pit slope stability design studies. Created as an outcome of the Large Open Pit (LOP) project, an international research and technology transfer project on the stability of rock slopes in open pit mines, this book expands on the hydrogeological model chapter in the LOP project’s previous book Guidelines for Open Pit Slope Design

The book comprises six sections which outline the latest technology and best practice procedures for hydrogeological investigations. The sections cover: the framework used to assess effect of water in slope stability; how water pressures are measured and tested in the field; how a conceptual hydrogeological model is prepared; how water pressures are modelled numerically; how slope depressurisation systems are implemented; and how the performance of a slope depressurisation program is monitored and reconciled with the design.

Guidelines for Evaluating Water in Pit Slope Stability offers slope design practitioners with a road map that that will help them decide how to investigate and treat water pressures in pit slopes. It provides guidance and essential information for mining and civil engineers, geotechnical engineers, engineering geologists and hydrogeologists involved in the investigation, design and construction of stable rock slopes

CONTENTS

Preface and Acknowledgements

Introduction

John Read, Geoff Beale, Marc Ruest and Martyn Robotham

1 Scope of LOP project hydrogeological studies

2 General impact of water on mining

3 Cost of managing water in slope stability

4 Goals of managing water in slope stability

5 General planning for mine water management

SECTION 1: FRAMEWORK – ASSESSING WATER IN SLOPE STABILITY

Geoff Beale, Mike Price and John Waterhouse

1.1 Fundamental parameters

1.2 The hydrogeological model

1.3 Managing water in open pit mines

SECTION 2: SITE CHARACTERISATION

Greg Doubek, Ashley Creighton, Mike Price and Mark Hawley

2.1 Planning field programs

2.2 Implementing field programs

2.3 Presentation, analysis and storage of data

SECTION 3: PREPARING A CONCEPTUAL HYDROGEOLOGICAL MODEL

Geoff Beale, Pete Milmo, Mark Raynor, Mike Price and Frederic Donzé

3.1 Introduction

3.2 Components of the conceptual model

3.3 Research outcomes from Diavik

3.4 Discrete Fracture Network (DFN) modelling

3.5 Summary of case studies

3.6 Factors contributing to a slope-scale conceptual model

3.7 Conclusions

SECTION 4: NUMERICAL MODEL

Loren Lorig, Jeremy Dowling, Geoff Beale, Michael Royle

4.1 Planning a numerical model

4.2 Development of numerical groundwater flow models

4.3 Use of pore pressures in numerical stability analyses

SECTION 5: IMPLEMENTATION OF SLOPE DEPRESSURISATION SYSTEMS

Geoff Beale, John De Souza, Rod Smith, Bob St Louis

5.1 Planning slope depressurisation systems

5.2 Implementation of a groundwater control program

5.3 Control of surface water

SECTION 6: MONITORING AND DESIGN RECONCILIATION

Chris Lomberg, Ian Ream, Rory O’Rourke and John Read

6.1 Monitoring

6.2 Performance assessment

6.3 Water risk management

APPENDIX 1

APPENDIX 2

1 Summary of drilling methods commonly used in mine hydrogeology investigations

2 Standardised hydrogeological logging form for use with RC drilling

3 Interpretation of data collected while RC drilling

4. Guidelines for drill-stem injection tests

5 Guidelines for running and interpreting hydraulic tests

6. Guidelines for the installation of grouted-in vibrating wire piezometer strings

7 Westbay multilevel system

APPENDIX 3

1 Background

2 Hydrograph analysis

3. DFN modelling

Appendix 4

4.1 Escondida East Wall

4.2 Chuquicamata

4.3 Radomiro Tomic

4.4 Antamina West wall

4.5 Jwaneng Diamond Mine South-east Wall

4.6 Cowal Gold Mine (CGM)

4.7 Whaleback South wall

4.9 La Quinua, Peru

APPENDIX 5

Case Study 1: Numerical modelling of the Northwest wall of the Diavik A154 pit

Case Study 2: Numerical modelling of the marl sequence at the Cobre Las Cruces mine, Andalucía, Spain

APPENDIX 6

1.0 The lattice formulation

2.0 Features of the Lattice Approach

3.0 Example application

4.0 Validation of Slope Model using experimental data from Coaraze test site, France

APPENDIX 7