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Risk Assessment: Underground Services Risk Assessment

Document Information

Field Value
Document Reference RA03
Issue Number 2
Issue Date 1 June 2026
Next Review 1 June 2027
Prepared By Sean Ashton
Approved By Aaron Mason, Director
Activity/Process Hazard Who/What Affected Existing Controls Pre-Control Risk (S/L/R) New Controls Required Post-Control Risk (S/L/R)
Using plans to identify services Poor quality or inaccurate plans Site personnel could be injured due to striking unidentified services • Plans provided that include the area to be excavated
• Utility provider contacted where plans are of poor quality
• Site personnel confirm they have plans for all service types (gas, electric, water, etc.)
4/3/12 (High) • Implement mandatory plan review meeting before excavation
• Develop digital plan overlay system for site use
Various departments, immediate to 3 months
4/2/8 (Moderate)
Locating services Undetected services Site personnel at risk of electric shock, burns, gas inhalation if services missed during scanning • Additional GPR or EML surveys for congested areas
• Color plans obtained from utility owners
• Service avoidance training for all personnel
• Data logging CAT and Genny provided (calibrated)
• Personnel trained and competent
• Visual inspection for service indicators
• Services marked beyond excavation footprint
• Utility scans continue as excavation progresses
5/3/15 (High) • Mandatory refresher training on CAT & Genny
• Ensure all teams have latest dual-frequency CAT4+ equipment
• Develop service location checklist before excavation
Training/Equipment departments, immediate
5/1/5 (Moderate)
Excavating near identified services Contact with live services during excavation Site personnel at risk of electric shock, burns, explosions, flooding • Excavation within 0.5m of services by hand with insulated tools
• Excavation by hand if service cannot be located
• Excavate alongside, not on top of services
• Marker tape as indication only
• Work ceases if unidentified service located
• Services in concrete not broken without isolation
• Contact utility owner if high risk
• Flame retardant/arc resistant clothing provided
5/3/15 (High) • Implement permit to break ground system
• Deploy physical barriers around exposed services
• Provide comprehensive insulated tool kits
• Improve service-specific PPE availability
Safety/Procurement, immediate
5/1/5 (Moderate)
Working around exposed services Unintentional damage to exposed services Site personnel, visitors at risk from damaged services. Interruption to public utilities • All exposed services protected and supported to prevent damage 4/3/12 (High) • Develop specific method statements for each service type
• Color-coded protection systems for different utilities
• Additional supervisor checks on protection
Safety/Supervisors, immediate to 1 month
4/1/4 (Low)
Moling near underground services Contact with services during moling operations Site personnel at risk from striking unidentified services during moling • Moling not done within 0.25m of indicated service location
• Greater clearance for larger diameter services
5/3/15 (High) • Improve tracking capabilities for mole devices
• Mandatory pre-moling service location plan
• Increase clearance to minimum 0.5m for all services
Technical/Operations, immediate
5/1/5 (Moderate)
Working near high-voltage electric cables Contact with high-voltage cables Site personnel at risk of severe electric shock or electrocution • Specific identification of HV cables on plans
• Liaison with electricity network operator
• Special permits for HV work
• Enhanced barriers and supervision
5/2/10 (High) • Specialist HV awareness training for supervisors
• Procure voltage detection equipment
• Network operator present for HV works
Training/Procurement, within 1 month
5/1/5 (Moderate)
Working near gas mains Contact with gas mains leading to gas release Site personnel and public at risk from explosion or asphyxiation • Specific identification of gas mains on plans
• Gas detection equipment available
• Emergency procedures for gas escape
• Special methods for medium/high-pressure gas
5/2/10 (High) • Add gas monitors to standard equipment
• Enhance emergency evacuation procedures
• Improve explosion-proof equipment availability
Safety/Procurement, immediate
5/1/5 (Moderate)
Emergency response to service strike Inadequate response to service damage Site personnel and public at risk from delayed or inadequate response • Emergency procedures for service strikes
• Utility company contact details available
• First aid equipment and trained personnel
5/2/10 (High) • Develop service-specific emergency response cards
• Regular emergency drills for service strikes
• Update emergency contacts monthly
Safety/Supervisors, immediate to monthly
5/1/5 (Moderate)

Key:

  • S = Severity (1-5 scale)
  • L = Likelihood (1-5 scale)
  • R = Risk Rating (S × L)
  • Risk Levels:
    • Low (1-3)
    • Moderate (4-8)
    • High (9-15)
    • Very High (16-25)
  • GS6 Guidance: Avoiding Danger from Overhead Power Lines