Canadian Natural Jackpine Mine Fluid Tailings Management Report Approval 9756H, as amended Submitted April 30, 2020 JPM-300-RPT-GT-000006 REV 0 Canadian Natural Jackpine Mine Fluid Tailings Management Report AER 2020 TABLE OF CONTENTS JACKPINE MINE CONCORDANCE TABLE ................................................................................ 7 1 INTRODUCTION .................................................................................................................. 10 2 TAILINGS MANAGEMENT ACTIVITIES .............................................................................. 11 2.1 AER Required Fluid Tailings Accounting ................................................................. 11 2.2 Management Level .................................................................................................. 11 2.3 Dedicated Disposal Area 1 ...................................................................................... 11 2.4 Sand Cell 1 .............................................................................................................. 12 2.5 Sand Cell 2 .............................................................................................................. 12 2.6 Fluid Cell 1 ............................................................................................................... 12 3 ANNUAL TAILINGS INVESTIGATION PROGRAM ............................................................. 13 3.1 Laboratory Testing ................................................................................................... 13 3.2 Survey ...................................................................................................................... 13 3.3 Classification of Treated Tailings, Fluid Tailings, and Clear Water Zone ................ 13 3.4 Methodology to Address Uncertainty in Data ........................................................... 14 3.4.1 Pond Surfaces .............................................................................................. 14 3.4.2 Date Reconciliation ...................................................................................... 14 3.4.3 Transitional Materials ................................................................................... 14 4 MODELLING ........................................................................................................................ 15 4.1 Pond Bottom and Mudline Interpretation ................................................................. 15 4.1.1 DDA 1 TT Mixed Tailings Deposit ................................................................ 15 4.1.2 Centrifuge Product ....................................................................................... 15 4.2 Mass of Fines Estimation ......................................................................................... 16 4.2.1 Transition Zone Material ............................................................................... 16 4.2.2 Centrifuge Product Entrained in CST Beaches ............................................ 16 5 TAILINGS DEPOSITS .......................................................................................................... 17 5.1 Beaching Operations and Performance ................................................................... 17 5.2 Centrifuge Deposits ................................................................................................. 17 5.2.1 DDA 1 Centrifuge Operation ........................................................................ 17 5.3 Thickened Tailings Mixed Deposits ......................................................................... 17 5.3.1 DDA 1 TT Mixed Deposit Operation and Performance ................................ 17 5.4 Atmospheric Fines Drying Deposit ........................................................................... 18 5.4.1 SC 2 AFD Pilot Deposit Operation and Performance ................................... 18 5.5 Settlement and Consolidation .................................................................................. 18 MINE GEOTECHNICAL AND GEOLOGY 2 Canadian Natural Jackpine Mine Fluid Tailings Management Report AER 2020 6 POND STATUS AND MASS OF FINES IN FLUID TAILINGS ............................................. 19 6.1 Fluid Tailings and Water Volumes ........................................................................... 19 6.2 Fluid Tailings Properties .......................................................................................... 19 6.3 Pond Capacity Projections ....................................................................................... 19 6.4 Mass of Fines Processed ......................................................................................... 20 6.5 Mass of Fines in Fluid Tailings ................................................................................. 20 6.6 Settlement and Consolidation .................................................................................. 20 7 TAILINGS WATER ............................................................................................................... 22 7.1 Site Water Balance .................................................................................................. 22 7.1.1 Clear Water Inventory .................................................................................. 23 7.2 Water Quality Results .............................................................................................. 24 8 EXISTING TAILINGS TECHNOLOGY SUMMARY .............................................................. 25 8.1 Thickened Tailings ................................................................................................... 25 8.1.1 Thickened Tailings Production ..................................................................... 25 8.1.2 Thickened Tailings Monitoring ...................................................................... 25 8.2 Centrifuge Product ................................................................................................... 25 8.2.1 Centrifuge Production ................................................................................... 26 8.2.2 Centrifuge Monitoring ................................................................................... 26 9 TAILINGS TECHNOLOGY RESEARCH AND SUMMARY OF IMPROVEMENTS .............. 27 10 ENVIRONMENTAL MONITORING (SUB-OBJECTIVE 2) ................................................... 28 11 STAKEHOLDER ENGAGEMENT ........................................................................................ 29 12 CLOSURE ............................................................................................................................ 30 13 AUTHENTICATION .............................................................................................................. 31 14 REFERENCES ..................................................................................................................... 32 15 ACRONYMS ......................................................................................................................... 33 16 GLOSSARY OF TERMS ...................................................................................................... 34 MINE GEOTECHNICAL AND GEOLOGY 3 Canadian Natural Jackpine Mine Fluid Tailings Management Report AER 2020 LIST OF TABLES Table 1: Activities Performed for ATI ................................................................................................... 13 Table 2: TT Mixed Tailings Deposit Performance ............................................................................... 18 Table 3: 2019 FT and Water Volumes................................................................................................. 19 Table 4: 2019 FT Properties ................................................................................................................ 19 Table 5: Available Pond Storage Projections ...................................................................................... 19 Table 6: Required Capacity Projections .............................................................................................. 20 Table 7: Mass of Fines in Ore ............................................................................................................. 20 Table 8: Characterization of Ore Feed ................................................................................................ 20 Table 9: Mass of Fines Present in FT .................................................................................................. 20 Table 10: Total Water Volume ............................................................................................................. 23 Table 11: TT Treatment Volumes ........................................................................................................ 25 Table 12: TT Process Monitoring ........................................................................................................ 25 Table 13: Centrifuge Product Treatment Volumes .............................................................................. 26 Table 14: Centrifuge Product Process Monitoring ............................................................................... 26 MINE GEOTECHNICAL AND GEOLOGY 4 Canadian Natural Jackpine Mine Fluid Tailings Management Report AER 2020 LIST OF FIGURES Figure 1: Site Plan ............................................................................................................................... 36 Figure 2: External