Volker W. Neth Canadian Diamond Drilling Association Banff, Alberta – June 04, 2018

1. Volker W. NethCanadian Diamond Drilling Association Banff, Alberta – June 04, 2018 Safe Drilling from Ice Covers

2. Drilling from Ice Covers • ICE PADS – to support drilling operations (long term loading) • ICE ROADS – provide a link to ICE PADS (short term loading)

3. Presentation Overview • CHALLENGES • ICE COVER • Basics of ice and snow • Examples of ice drill pads and ice roads • ICE ENGINEERING APPLICATIONS • Comprehensive planning (with client) • Advanced analytical models • Improved construction methods • Monitoring and safety • SAFETY

4. Challenges • Ice covers are temporary working platforms lasting only a couple of months. Their usefulness depends largely on: • Environmental changes: • Ambient temperature change (short term); • Climate change (long term, project location dependent). • Ice thickness • Naturally grown ice (with snow cover); • Thickening through flooding and/or spraying.

5. Historical Winter Construction Windows 1960 to 2006 – Kiegler 2009 SHOULDER SEASON OPERATING WINDOW SHOULDER SEASON OCT NOV DEC JAN FEB MAR APR MAY JUN

6. Flooding Pump

7. Ice Thickness and Buoyancy

8. Examples of Ice Structures ICE PADS Ice platforms to support drill rigs ICE ROADS/ICE BRIDGES Ice road on crater lake in Siberia Tibbitt to Contwoyto Winter Road

9. Exploratory Drill Rig at a Mine, NWT, 2015

10. Geotechnical Drilling, Northern Ontario, February 2018

11. Geotechnical Drilling, Snow on Ice

12. Ice Road with Markers in NE Russia

13. One Lane Ice Road

14. Some Ice Engineering Basics Operational Ice Design Criteria • DESIGN CRITERIA 1 To operate within the allowable limits of freeboard • DESIGN CRITERIA 2 Not to exceed the maximum allowable ice stresses

15. Types of Freeboard (FB) Positive Freeboard Negative Freeboard

16. Almost all on-ice operations involve SNOW! The chosen snow management method determines whether an on-ice project is a success or a failure!

17. Snow On Ice Snow Characteristics Snow insulates and suppresses ice growth Snow increases weight on ice Snow cover hides cracks in ice Snow patches covers thin ice (danger!!) Weight of snow impacts operation

18. On-Ice Drilling & Ice Engineering Applications • Planning..ice growth prediction • Advanced analytical models • To determine carrying capacity • Ice thickness (capacity increases exponentially with thickness) • Load distribution • Sort term/long term loading • Improved construction methods • Early, proper snow management • Use spray techniques • Monitoring and safety • Thickness, ice temperature, ice strength • To ensure the safety of the on-ice personnel

19. Predicted and actual ice thicknesses at Hope Bay, NU, 2011/2012 LEGEND CANADIAN ARCTIC (FRESH WATER) MEASURED ICE THICKNESS ( SOME SNOW) FIELD DATA ±10cm BANDWIDTH NO SNOW (predicted) WITH SNOW (predicted) 170 16.2.15 160 150 23.1.15 140 130 120 110 100 90 ICE THICKNESS (CENTIMETERS) 80 70 60 50 40 30 20 10 OCT 1 JAN 15 FEB 1 OCT 15 NOV 1 DEC 1 DEC 15 FEB 15 MAR 1 NOV 15 JAN 1 DATE

20. Ice Thickness Prediction for Equipment Deployment 55 QUAD AXEL FUEL TRAILER LOADED (52”) 50 45 GEOTECH RIG ON ICE PAD (41”) 40 ORBIT-GARANT RIG ON ICE PAD; RIMPULL LOADED (40”) 35 KOMATSU D5 PULLING ORBIT-GARANT ROD SLOOP (33”) IT38G + LARUE D50; RIMPULL EMPTY (30”) 30 CHALLENGER 75 & 85 (27”) ICE THICKNESS (INCHES) 25 TELE HANDLER PULLING GEOTECH RIG SHACK (25”) 20 SNOW CAT (17”) 15 BOMBI (12”) 10 SNOW MOBILE (7”) PERSON ON ICE (4”) 5 DEC 11 DEC 18 NOV 9 JAN 11 JAN 14 NOV 19 OCT 25 DEC 26 OCT 30 DEC 6 FEB 4 OCT 15 FEB 1 JAN 15 FEB 15 NOV 15 DEC 15 JAN 1 NOV 1 DEC 1 DATE OCT 20, DORIS LAKE – Freeze-up date

21. Point Load vs. Distributed Load HALF LOADS ICE STRESSES SAVINGS ICE STRESSES SUPERIMPOSED HALF LOAD MAXIMUM STRESS AT P/2 SINGLE LOADS MAXIMUM STRESS AT P DEFLECTIONS SUPERIMPOSED HALF LOAD DEFLECTIONS SINGLE LOADS

22. Effect of Load Distribution Maximum Flexural Stress: 600 kPa Modelled Ice Thickness: 80 cm Maximum Flexural Stress: 300 kPa Modelled Ice Thickness: 80 cm

23. Spray Pump Photo courtesy of Big Ice Services

24. Photo courtesy of Big Ice Services

25. ON-ICE SAFETY Travelling & working on ice is risky! Tetra Tech considers Safety as an integral part and has the highest priority of any on-ice project.

26. Main Reasons for On-Ice Accidents • Communication gap • Don’t know the ice thickness • Don’t know the load • Wandering off the established road • Placing and leaving loads on the ice • Working alone

27. Accidents on Floating Ice Covers • Recreation related accidents: • Between 1996 and 2006 nearly 500 people died in Canada (Canadian Red Cross Society, 2006) • 4 Examples of work related accidents: • Island Lake – MB (January 2002) – Tetra Tech as expert witness • Peace River – AB (January 7, 2005) – “Best Practice … • Opapimaskin Lake – ON (January 14, 2012) - loader retrieval • Near Ft. Nelson – BC (February 20, 2014) – excavator ..

28. January 14, 2012 Incident: Break Through Hole

29. March 09, 2012 : Crane Set-Up

30. March 09, 2012: Hooking-Up Loader

31. March 09, 2012 : Loader Retrieval

32. Ice Break-Through of an Excavator in Northern BC, February, 2014

33. Break Through Consequences Operator injury or death Survivor compensation Equipment loss Cost of equipment retrieval Cost of environmental clean-up Damage to reputation of company/industry The cost of proper safety planning is minimal compared to the cost of an accident!

34. Summary • Increasing ambient temperatures represent a challenge when drilling from ice covers. • Basics of ice and snow. • Importance of planning when drilling from ice: • Analyze project location specific environment • Advanced analytical models; • Improved construction methods. • Relationship between monitoring and safety.

35. Safe Drilling from Ice CoversHave a safe stay in Banff!Thank You !