Mobile Maintenance Supervisor

Mariana Minerals is a software-first, vertically integrated minerals company supplying critical minerals for energy, AI, and defense technologies. The Mobile Maintenance Supervisor is a hands-on working supervisor responsible for leading a team of maintenance technicians and supporting the safety, reliability, and availability of Mariana's growing mobile mining fleet. The role combines technical leadership, field troubleshooting, crew development, maintenance planning, and day-to-day operational decision-making. Schedule: 7 days on / 7 days off, working 12-hour shifts; supervisors rotate between day and night shifts as operations expand and must be available for on-call coverage. Work environment: approximately 70% fieldwork and 30% office-based work.

Responsibilities

Lead, supervise, and develop a team of maintenance technicians while maintaining a safety-first mentality and a strong culture of accountability, teamwork, and continuous improvement; Conduct safety meetings and workplace inspections, address hazards, and ensure work is performed in accordance with company policies and applicable safety requirements; Work hands-on alongside technicians to troubleshoot, diagnose, and repair heavy mobile mining equipment, including mechanical, hydraulic, and electrical systems; Prioritize and coordinate daily maintenance activities based on safety, equipment criticality, production needs, labor, parts, and available resources; Perform advanced troubleshooting and failure analysis using diagnostic tools, schematics, technical manuals, and equipment documentation; Drive equipment reliability and availability through preventative maintenance, repair-quality review, equipment-status tracking, and identification of recurring failures; Coordinate with planners, operations, and vendors to schedule repairs, manage work orders, source parts, and communicate repair requirements and expected downtime; Train and mentor technicians, provide technical leadership in the field, and provide on-call support as needed, including serving as the senior maintenance representative when leadership may not be onsite

Requirements

Previous supervisory, lead technician, or crew-leadership experience, with the ability to coach technicians and provide technical direction in the field; Minimum of 5 years of mining maintenance experience, with strong hands-on experience supporting heavy mobile mining equipment; Strong troubleshooting and failure-analysis skills across mechanical, hydraulic, and electrical systems, including the ability to read hydraulic and electrical schematics; Experience with Caterpillar mobile mining equipment and electronic diagnostic tools, including familiarity with CAT ET and CAT SIS; Strong communication, organization, and problem-solving skills, with the ability to make decisions, take ownership, and work effectively in a growing operation; Experience using maintenance tracking systems and Microsoft Office applications; Valid driver's license required

Nice to have

Welding experience; Experience with autonomous mining technology; Direct experience with CAT 777 haul trucks and/or CAT 992K wheel loaders

Benefits

Housing and relocation assistance options are available