Project Engineer

About Mariana Minerals Mariana Minerals is a software-first, vertically integrated minerals company on a mission to supply the critical minerals powering modern energy, AI, and defense technologies. We’re reimagining the minerals supply chain by combining deep industry expertise with advanced software, automation, and data-driven decision-making. The Project Engineer designs and deploys first-of-a-kind mining and refining technologies at our Moab site. In this role, you will work across Mariana's process development, software, plant engineering, project execution, and operations teams to plan, build, and deliver the cross-functional projects that move our plant forward. The work varies week to week, from scoping a project and sizing equipment to standing beside the mechanic and electrician during startup. You will own projects from idea to handover and build new skills along the way. Responsibilities Scope, design, and lead process improvement and capital projects from concept through commissioning Develop process flow diagrams, P&IDs, mass and energy balances, and equipment specifications Size and select pumps, tanks, piping, and other process equipment Use plant data to find bottlenecks, improve recovery, and cut costs Work with the project mechanic and project electrician on installs, checkout, and startup Partner with controls and operations teams on control strategies and operating procedures Lead hazard reviews and management of change, and keep projects compliant with site safety standards Manage project scope, schedule, and budget, including vendor and contractor coordination Qualifications & Experience Bachelor's degree in Mechanical Engineering preferred or another related engineering degree Process or mechanical engineering experience in mining, chemical, oil & gas, or other heavy industrial operations, 4+ years Hands-on experience taking projects from design through commissioning and startup Comfort reading and producing P&IDs, PFDs, and equipment datasheets Strong data skills; experience with process data historians, Python, or similar tools is a plus Experience with hydrometallurgy, leaching, solvent extraction, or electrowinning is a plus Comfort working independently and a willingness to jump into unfamiliar problems EIT or PE is a plus Schedule Monday-Friday Days Occasional weekends based on project needs Working Environment & Physical Requirements Work in the processing plant in all weather conditions, including extreme temperatures, with exposure to fumes, dust, diesel, solvents, sulfuric acid, and other hazardous materials Able to stand, climb, bend, and kneel for extended periods, including work at heights and in tight spaces Adequate visual acuity, depth perception, and hearing (with correction or aids if needed) to work safely around operating equipment Ability to lift a minimum of 50 pounds Ability to wear required PPE at all times on site, including hard hat, safety glasses, steel-toe boots, hearing protection, and respiratory protection when needed Our culture is built on four principles: Everyone Gets Home Safe. We never put speed or cost ahead of people. Extreme Ownership. We take full responsibility for outcomes, relentlessly driving toward solutions. Engineer Out Requirements, then Automate. We simplify, optimize, and then automate for scale. Share Your Legos. We collaborate openly, share knowledge, and empower each other to build bigger, better solutions. Join us as we build the future of responsible mineral sourcing and supply!