Safe Drilling from Ice Covers Volker W Neth

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Safe Drilling from Ice Covers Volker W. Neth Canadian Diamond Drilling Association Banff, Alberta

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

Drilling from Ice Covers • ICE PADS – to support drilling operations (long term

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

Presentation Overview • CHALLENGES • ICE COVER ▪ Basics of ice and snow ▪

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 3

Challenges • Ice covers are temporary working platforms lasting only a couple of months.

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. 4

Historical Winter Construction Windows 1960 to 2006 – Kiegler 2009 SHOULDER SEASON OPERATING WINDOW

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

Flooding Pump 6

Flooding Pump 6

Ice Thickness and Buoyancy 7

Ice Thickness and Buoyancy 7

Examples of Ice Structures • ICE PADS • Ice platforms to support drill rigs

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 8

Exploratory Drill Rig at a Mine, NWT, 2015 9

Exploratory Drill Rig at a Mine, NWT, 2015 9

Geotechnical Drilling, Northern Ontario, February 2018 10

Geotechnical Drilling, Northern Ontario, February 2018 10

Geotechnical Drilling, Snow on Ice 11

Geotechnical Drilling, Snow on Ice 11

Ice Road with Markers in NE Russia 12

Ice Road with Markers in NE Russia 12

One Lane Ice Road 13

One Lane Ice Road 13

Some Ice Engineering Basics Operational Ice Design Criteria • DESIGN CRITERIA 1 To operate

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 14

Types of Freeboard (FB) Positive Freeboard Negative Freeboard 15

Types of Freeboard (FB) Positive Freeboard Negative Freeboard 15

Almost all on-ice operations involve SNOW! The chosen snow management method determines whether an

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

Snow On Ice Snow Characteristics • Snow insulates and suppresses ice growth • Snow

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 17

On-Ice Drilling & Ice Engineering Applications • Planning. . ice growth prediction • Advanced

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 18

Predicted and actual ice thicknesses at Hope Bay, NU, 2011/2012 170 160 150 140

Predicted and actual ice thicknesses at Hope Bay, NU, 2011/2012 170 160 150 140 130 LEGEND CANADIAN ARCTIC (FRESH WATER) MEASURED ICE THICKNESS ( SOME SNOW) FIELD DATA ± 10 cm BANDWIDTH NO SNOW (predicted) WITH SNOW (predicted) 16. 2. 15 23. 1. 15 120 110 100 ICE THICKNESS (CENTIMETERS) 90 80 70 60 50 40 30 20 1 0 OCT 15 NOV 15 DEC 15 DATE JAN 15 FEB 15 MAR 1 19

Ice Thickness Prediction for Equipment Deployment 55 QUAD AXEL FUEL TRAILER LOADED (52”) 50

Ice Thickness Prediction for Equipment Deployment 55 QUAD AXEL FUEL TRAILER LOADED (52”) 50 45 GEOTECH RIG ON ICE PAD (41”) ORBIT-GARANT RIG ON ICE PAD; RIMPULL LOADED (40”) 40 35 KOMATSU D 5 PULLING ORBIT-GARANT ROD SLOOP (33”) IT 38 G + LARUE D 50; RIMPULL EMPTY (30”) ICE THICKNESS (INCHES) 30 25 CHALLENGER 75 & 85 (27”) TELE HANDLER PULLING GEOTECH RIG SHACK (25”) 20 OCT 15 NOV 15 DEC 15 JAN 1 DATE JAN 15 FEB 4 JAN 11 JAN 14 DEC 26 DEC 18 NOV 19 NOV 9 (4”) OCT 25 5 OCT 30 SNOW MOBILE (7”) PERSON ON ICE DEC 11 10 BOMBI (12”) DEC 6 15 SNOW CAT (17”) FEB 15 OCT 20, DORIS LAKE – Freeze-up date 20

Point Load vs. Distributed Load HALF LOADS ICE STRESSES SAVINGS SUPERIMPOSED HALF LOAD MAXIMUM

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

Effect of Load Distribution Maximum Flexural Stress: 600 k. Pa Modelled Ice Thickness: 80

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

Spray Pump Photo courtesy of Big Ice Services 23

Spray Pump Photo courtesy of Big Ice Services 23

Photo courtesy of Big Ice Services 24

Photo courtesy of Big Ice Services 24

ON-ICE SAFETY Travelling & working on ice is risky! Tetra Tech considers Safety as

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. 25

Main Reasons for On-Ice Accidents • Communication gap • Don’t know the ice thickness

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 26

Accidents on Floating Ice Covers • Recreation related accidents: – Between 1996 and 2006

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. . 27

January 14, 2012 Incident: Break Through Hole 28

January 14, 2012 Incident: Break Through Hole 28

March 09, 2012 : Crane Set-Up 29

March 09, 2012 : Crane Set-Up 29

March 09, 2012: Hooking-Up Loader 30

March 09, 2012: Hooking-Up Loader 30

March 09, 2012 : Loader Retrieval 31

March 09, 2012 : Loader Retrieval 31

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

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

Break Through Consequences • Operator injury or death • Survivor compensation • Equipment loss

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! 33

Summary • Increasing ambient temperatures represent a challenge when drilling from ice covers. •

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. 34

Safe Drilling from Ice Covers Have a safe stay in Banff! Thank You !

Safe Drilling from Ice Covers Have a safe stay in Banff! Thank You ! 35