HIGH RIVER GOLD MINES LTD Technical Report on Bissa Zandkom Project, Burkina Faso September 2010 HIGH RIVER GOLD MINES LTD Technical Report on Bissa Zandkom Project, Burkina Faso 2 CONTENTS CONTENTS 1 TITLE PAGE ..........................................................................................................................2 2 CONTENTS ............................................................................................................................I 3 SUMMARY...........................................................................................................................1 4 INTRODUCTION AND TERMS OF REFERENCE .........................................................................7 4.1 Technical Report .....................................................................................................................7 4.2 Purpose of Technical Report...................................................................................................7 4.3 Sources of Information and Data............................................................................................7 4.4 The Scope of Each Qualified Person and Author ....................................................................8 5 RELIANCE ON OTHER EXPERTS............................................................................................ 11 6 PROPERTY DESCRIPTION AND LOCATION............................................................................ 12 7 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY ........ 13 8 HISTORY ............................................................................................................................ 17 9 GEOLOGICAL SETTING ........................................................................................................ 19 9.1 Regional Geology ..................................................................................................................19 9.2 Geology of the Bissa-Zandkom Area.....................................................................................20 10 DEPOSIT TYPE .................................................................................................................... 24 11 MINERALIZATION............................................................................................................... 25 12 EXPLORATION.................................................................................................................... 37 13 DRILLING AND TRENCHING................................................................................................. 40 13.1 Trenching ..............................................................................................................................40 13.2 Core Drilling...........................................................................................................................40 13.3 Reverse Circulation Drilling...................................................................................................41 13.4 Surveying...............................................................................................................................41 13.5 Drilling Pattern and Density..................................................................................................42 13.6 Field Procedures....................................................................................................................43 14 SAMPLING METHOD AND APPROACH................................................................................. 45 15 SAMPLE PREPARATION, ANALYSES AND SECURITY.............................................................. 48 15.1 Sample Preparation & Analyses............................................................................................48 15.2 Quality Assurance & Quality Control Programs....................................................................49 15.3 Specific Gravity Data .............................................................................................................51 15.4 Sample Security.....................................................................................................................52 16 DATA VERIFICATION........................................................................................................... 53 17 ADJACENT PROPERTIES ...................................................................................................... 54 18 MINERAL PROCESSING AND METALLURGICAL TESTING ....................................................... 55 18.1 Introduction ..........................................................................................................................55 61-0805/MM501 Final V 1.0 Page i September 2010 HIGH RIVER GOLD MINES LTD Technical Report on Bissa Zandkom Project, Burkina Faso 18.2 Pre Feasibility Study Testwork..............................................................................................55 18.2.1 AMMTEC Testwork........................................................................................................55 18.2.2 Mineralogical Examination of Primary (Sulphide) Ore Samples ...................................58 18.2.3 Genivar PFS Report .......................................................................................................59 18.3 AMMTEC Feasibility Study Test Programme.........................................................................59 18.3.1 Samples Selected ..........................................................................................................59 18.3.2 Head Cyanide Leach Test Results..................................................................................60 18.3.3 Head Cyanide Leach Tests at Varying Grind Sizes.........................................................62 18.3.4 Head Cyanide Leach Tests at Varying Cyanide Concentrations....................................62 18.3.5 Effect of Pre-Oxygenation.............................................................................................62 18.3.6 Effect of Air Sparging.....................................................................................................62 18.3.7 Gravity Recoverable Gold (GRG) Testwork ...................................................................62 18.3.8 Mineralogical Examination ...........................................................................................63 18.3.9 Physical Testwork..........................................................................................................63 18.3.10 Equilibrium Carbon Loading Testwork......................................................................63 18.4 Flowsheet Description ..........................................................................................................64 18.4.1 General..........................................................................................................................64 18.4.2 Crushing ........................................................................................................................64 18.4.3 Grinding.........................................................................................................................64 18.4.4 CIL Circuit ......................................................................................................................65 18.5 Tailings Pond .........................................................................................................................65 18.6 Process Water Needs............................................................................................................66 18.7 Raw Water Supply.................................................................................................................66 18.8 Plant Labour..........................................................................................................................68 18.9 Process Operating cost .........................................................................................................68 19 MINERAL RESOURCE AND MINERAL RESERVE ESTIMATES ................................................... 70 19.1 Introduction ..........................................................................................................................70 19.2 Database Compilation...........................................................................................................71 19.2.1 Drilling...........................................................................................................................71 19.3 Solid Body Modelling ............................................................................................................75 19.4 Compositing and Sub-Domaining..........................................................................................78 19.5 Top Cut Analysis....................................................................................................................80 19.6 Variography...........................................................................................................................81 19.6.1 Bissa ..............................................................................................................................81 19.6.2 Boken ............................................................................................................................82 19.7 Block Modelling.....................................................................................................................83 19.8 Grade Interpolation