1

Best Practice Excavations 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?

9

10

11

Common MythsCommon 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-planningSource(s) of site informationSoil factors to considerNatural/Artificial HazardsStatic 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

15

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

17

18

19

Agenda – Filling & Compacting

20

Soil ClassificationSoil Classification

Hard & CompactHard & Compact

Likely to Crack or CrumbleLikely to Crack or Crumble

Soft, Sandy, or LooseSoft, 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 ControlsEngineered Hazard Controls

Metal Trench Boxes

Trench Shields

Pneumatic & Hydraulic Shoring Systems

Wood Shoring Systems

25

26

27

28

29

30

Ground Disturbance PlanningGround 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

32

33

Confined Space Entry Code of Confined Space Entry Code of PracticePractice 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

InspectionsInspections

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

38

39

Closeout

Questions?

Course evaluations

Clean up your station