1 Excavations Best Practice Excavations

2 Agenda - Introduction Statistics Excavations - Best Practices Question Period

3 Presentation Introduction Information Source - ACSA Safe Trenching, Excavation and Ground Disturbance Course Purpose Objective Primary Underlying Cause – INADEQUATE HAZARD ID & CONTROL

4 Statistics – Fatalities – Who is at Risk? 99% are males Avg Age – 35 years Highest risk group – Labourers Lowest Risk group – Managers Employees small companies – Highest Risk Employees large companies – Lowest Risk Unsupported tren/exc highest risk Supported tren/exc lowest risk

5 Foundation – Company Health & Safety Program Financial Benefits Legal Requirements Moral Obligations Due Diligence

6 Glossary of Terms Angle of repose Backfill Back slopes Barricades Bell Hole Cage Cave-in Closed sheeting Confined space Ground disturbance Excavation Kick out Open Cut Soil mass Surcharge load Trench Spoil pile

7 Primary causes of accidents related to ground disturbances are: Inadequate Hazard Assessment/Control Failure to test/classify soil conditions Failure to install safeguards Inadequate timbering/ use of defective materials Inadequate protection for surcharge loads Not allowing for changing weather conditions

8 Hazard Assessments  What is a Hazard?  What is a Hazard Assessment?  When is a Hazard Assessment Conducted?  What Are the Control Measures?

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11 Common Myths Myth # 1 “It is possible for a worker to out run a collapsing wall inside a trench or excavation" Myth # 2 "Dirt smells or sounds peculiar just before it caves in" Myth # 3 “A rope tied around the waist and extended to the top of the trench will help the rescuers find you if a cave-in occurs.

12 Work Site Hazard Analysis  Who should be involved in the process?  What should be included in the analysis?  Does it need to be documented?  Should responsibilities be assigned?  What responsibilities need to be addressed?

13 Site Hazard Assessment Process  Project pre-planning  Source(s) of site information  Soil factors to consider  Natural/Artificial Hazards  Static Loads  Dynamic Loads

14 Using One-Call Guidelines Purpose Making the Call Responsibilities of Facility Owners Locate Marks Lifespan of locate marks Hand Exposure and Control Zones Fibre Optic Cables Frozen Ground Extended Work Sites

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16 Guidelines for Safe Construction near Pipelines o What is a controlled area? o What is a right-of-way? o Your responsibilities o Pipeline Owner Responsibilities

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19 Agenda – Filling & Compacting

20 Soil Classification  Hard & Compact  Likely to Crack or Crumble  Soft, Sandy, or Loose

21 Factors Affecting Soil Stability Unsupported Vertical Walls Shock and Vibration Freeze/Thaw Effects

22 Types of Slope Failures Wedge Slide Slab Slide Circular Slide Toppling Slide

23 Soil Terminology Cemented Fissured Cohesive Granular

24 Engineered Hazard Controls Metal Trench Boxes Trench Shields Pneumatic & Hydraulic Shoring Systems Wood Shoring Systems

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30 Ground Disturbance Planning  Safety and The Environment  Waste Management Practices & Procedures  Site Hazard Controls - Administrative

31 Procedures for Excavation Ground Conditions Depth & Size of Pipe, etc. Proximity of Existing Utilities and Surface Structures

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33 Confined Space Entry Code of Practice Identification Hazards & Hazard assessments Atmospheric Testing Associated hazards Task Competencies Ventilation Personal Protective Equipment Rescue Legislative Requirements

34 Legislation Review Employer Worker Prime Contractor Serious Accidents Non- Compliance

35 Environmental Protection Environmental Assessment Soil Management Waste Management Air Quality Noise Waterways Emergency Response

36 Inspections Inspections What is an Inspection? Inspection Policy On-going & Formal Inspections

37 Emergency Response Planning (ERP) Emergency Contacts Designated Roles ERP Systems Testing Emergency Access & Egress Buried Worker Video/Exercise

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39 Closeout Questions? Course evaluations Clean up your station