Key Responsibilities and Required Skills for Underground Mechanic

🎯 Role Definition

As an Underground Mechanic you will maintain and repair heavy mobile equipment, production machines and underground support systems to maximize equipment availability and ensure safe, compliant operations. You will perform preventive and corrective maintenance, diagnose complex mechanical and electrical failures, fabricate and install parts in confined and hazardous environments, and document maintenance work in the CMMS. This role demands a proactive, safety-first mindset, excellent troubleshooting and welding skills, and the ability to work rotating shifts and be on-call for emergency repairs.

📈 Career Progression

Typical Career Path

Entry Point From:

Apprentice Heavy-Duty/Diesel Mechanic
Mobile Equipment Technician / Service Technician
Maintenance Assistant / Millwright Apprentice

Advancement To:

Lead Underground Mechanic / Senior Mechanic
Maintenance Supervisor / Foreman
Reliability Engineer or Maintenance Planner
Mine Maintenance Manager / Superintendent

Lateral Moves:

Diesel Mechanic (Surface / Mobile Fleet)
Millwright / Fabrication Specialist
Maintenance Planner or Parts Coordinator

Core Responsibilities

Primary Functions

Perform comprehensive preventive maintenance and scheduled inspections on underground mobile equipment (loaders, haul trucks, bolters, drills, and scoop trams) to maintain production uptime and meet maintenance KPIs; document completed PMs in the CMMS with accurate labour and parts reporting.
Diagnose and repair complex diesel engine failures including fuel system, turbochargers, cooling systems and exhaust after-treatment components in-line with manufacturer specifications and emissions standards.
Troubleshoot, repair and calibrate hydraulic systems (pumps, valves, cylinders, hoses, fittings) including fabrication and replacement of hydraulic hoses and fittings to OEM torque and pressure ratings.
Diagnose and repair electrical and electronic control systems: 12V/24V systems, alternators, starter motors, wiring harnesses, sensors, controllers, and PLC-based machine control units used on underground equipment.
Perform heavy mechanical overhauls and rebuilds of drivetrains, gearboxes, axles, suspensions and final drives; coordinate hoisting and rigging requirements in confined underground spaces.
Fabricate and weld replacement components and brackets on-site using MIG/TIG and stick welding methods, including fitting, jigging and grinding to restore structural integrity and machine fitment.
Conduct root-cause troubleshooting using onboard diagnostics, multimeters, pressure gauges, borescopes and manufacturer diagnostic software to resolve intermittent and recurring faults.
Execute emergency roadside and in-bay repairs underground, working under time pressure to safely restore equipment to service while following lockout/tagout and confined-space procedures.
Perform brake system inspections and repairs (service brakes, emergency brakes, retarder systems) and adjust braking systems to meet safety and performance standards.
Service and maintain compressed air, pneumatic and lubrication systems; replace filters, pumps, reservoirs and automatic lubrication systems to prevent premature component failure.
Install and maintain underground safety and auxiliary equipment such as ventilation fans, underground conveyors, pumps, lighting systems and communication hardware to ensure safe working conditions.
Maintain accurate maintenance records, parts usage logs and work orders in the Computerized Maintenance Management System (CMMS); recommend parts reorder levels and assist with inventory control.
Support shutdowns and turnarounds: plan scope, estimate parts and labour, lead or coordinate trades for complex rebuilds and major component replacements.
Conduct pre-shift inspections, pre-start checks and handovers; report defects and hazards to supervision and ensure follow-up corrective action and documentation.
Participate in incident investigations and safety root-cause analysis by providing mechanical expertise and implementing corrective maintenance actions to prevent recurrence.
Mentor and train junior mechanics and apprentices on safe underground maintenance practices, diagnostic techniques and proper use of tools and PPE.
Follow mine-specific regulations and safety procedures including confined-space entry, gas monitoring, H2S awareness, mine rescue protocols and personal protective equipment requirements at all times.
Coordinate with parts suppliers, OEM service reps and external contractors for warranty claims, technical support and specialty repairs; ensure quality control on outsourced work.
Conduct planned equipment modifications and upgrades per engineering change requests, install OEM retrofit kits and verify performance through post-installation testing.
Monitor and manage tooling, jacks, lifts, slings and rigging equipment; ensure calibration of torque tools and testing of pressure vessels and hoses to regulatory standards.
Support reliability improvement initiatives by identifying chronic failure modes, proposing design or maintenance changes, and participating in preventive reliability projects.
Maintain cleanliness, organization and safety in the shop and underground service areas, ensuring spill response, hazardous waste handling and PPE compliance are observed.

Secondary Functions

Assist maintenance planners and schedulers by providing accurate labour and time estimates for repairs, parts lead times and resource requirements.
Support continuous improvement initiatives such as PM optimization, root cause corrective actions and lean maintenance practices to increase equipment uptime and reduce mean time to repair (MTTR).
Act as on-call mechanic as required by shift rotation to respond to emergency breakdowns and production stoppages.
Participate in safety committees, toolbox talks and pre-start safety meetings to share mechanical insights and hazard controls with operational staff.
Provide input into spare parts inventory strategies and capital repair forecasts based on hands-on diagnostic trends and supplier lead times.
Help coordinate contractor scope and access for specialty repairs, ensuring permits, safety plans and supervision are in place prior to work starting.
Maintain and update standard work instructions, repair procedures and mechanical drawings to improve team knowledge retention and transfer.
Assist with light civil and ground support tasks in the workshop such as rigging, crane assist, and maintaining lifting equipment certifications.

Required Skills & Competencies

Hard Skills (Technical)

Diesel engine diagnosis and repair (heavy-duty, two- and four-stroke engines) including fuel systems, turbochargers and emissions components.
Hydraulic system service, troubleshooting and hose fabrication for high-pressure mobile circuits.
Heavy equipment electrical systems, CANbus/vehicle networks, sensors, relays and starter/charging systems.
Welding and fabrication: MIG, TIG and stick welding for structural repair and part fabrication; ability to read and interpret fabrication drawings.
Brake systems, driveline, transmission and final drive overhaul skills for mobile mining equipment.
Proficiency with diagnostic tools: multimeters, pressure gauges, thermal imaging, oscilloscopes and OEM diagnostic software.
Computerized Maintenance Management Systems (CMMS) experience for work order management and parts tracking.
Blueprint and schematic reading (mechanical, hydraulic and electrical diagrams).
Confined space entry procedures, gas monitoring, mine rescue basic awareness and ability to work safely in ventilation-limited environments.
Use of shop and field tooling: hydraulic jacks, hoists, torque wrenches, bench presses, and alignment equipment.
Preventative maintenance planning and execution, FMECA/RCM awareness and reliability-centred maintenance concepts.
Welding inspection, non-destructive testing awareness (visual, magnetic particle, dye penetrant) helpful.
Forklift and mobile crane operation (or ability to obtain certifications) for handling heavy components.

Soft Skills

Strong problem-solving and analytical thinking with attention to root cause and long-term reliability.
Clear verbal and written communication to create accurate maintenance reports and to communicate complex technical issues to non-technical stakeholders.
Teamwork and collaboration across production, planning and safety teams in a 24/7 operation.
Self-motivated, disciplined work ethic with ability to perform independently in remote and challenging underground conditions.
Time management and prioritization to balance reactive emergency repairs with scheduled maintenance.
Adaptability and resilience to work rotating shifts, extended hours and emergency call-outs.
Coaching and mentoring ability to develop junior technicians and share best practices.
Safety leadership with the ability to recognize hazards, stop unsafe work and influence a culture of compliance.

Education & Experience

Educational Background

Minimum Education:

High School Diploma or GED with completion of a heavy-duty mechanic apprenticeship or trade school program.

Preferred Education:

Technical diploma or certificate in Heavy Duty/Commercial Vehicle Mechanics, Mechanical Engineering Technology, or Millwright program.
Additional training in diesel technology, hydraulics, electrical systems, or welding certifications.

Relevant Fields of Study:

Heavy Duty/Commercial Vehicle Mechanics
Diesel & Powertrain Technology
Mechanical Engineering Technology
Welding and Fabrication
Millwright / Industrial Mechanics

Experience Requirements

Typical Experience Range:

3–8 years of hands-on heavy equipment maintenance experience, with at least 2–4 years specifically in underground mining or tunnelling environments.

Preferred:

5+ years of underground mining mechanic experience with demonstrated record of complex repairs, major equipment overhauls and maintenance leadership.
Experience with specific underground equipment types (LHDs, scoop trams, haul trucks, roof bolters, drill rigs) and OEM diagnostic platforms.

Certifications (preferred/required depending on site):

Confined Space Entry and Rescue
First Aid / CPR and Mine Rescue training
WHMIS / Hazardous Materials training
H2S Alive (where applicable)
Forklift / Mobile Crane / Rigging certifications
Manufacturer-specific training or trade certifications (e.g., Cummins, Caterpillar, Sandvik, Epiroc)