Sr. Metallurgical Process 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 how minerals are sourced, refined, and optimized by combining deep industrial expertise with software, automation, and data-driven decision-making. Join us as we build the future of responsible mineral sourcing and supply. ROLE OVERVIEW Mariana Minerals is seeking a highly motivated Sr. Metallurgical Process Engineer to support process development activities & scale-up experiments at our CopperOne mine outside of Moab, UT. You will oversee engineering and operations of our bioleaching columns and other pilot scale equipment supporting current and future mine projects. This role is highly hands-on and will play a key role in bridging R&D and operations, helping scale technologies from laboratory development through pilot demonstration and ultimately to commercial mining. You will work closely with R&D, technicians, metallurgists, and cross-functional teams to ensure processes are robust, efficient, and suitable for future development & scale-up. WHAT YOU’LL DO - Operate, troubleshoot, and improve leaching columns and other pilot-scale processing equipment in collaboration with technicians - Design and execute pilot-scale experiments to bridge learnings between R&D and commercial mine scale - Develop and maintain key process documentation including PFDs, P&IDs, operating procedures, mass balances, etc - Analyze experimental and operational data to identify opportunities for process optimization and scale-up - Support development of automated monitoring and optimization tools in collaboration with software and machine learning teams - Ensure safe operations by supporting EHS, hazard assessments, risk management, and management of change processes WHAT YOU’LL BRING - B.S., M.S., or PhD in Chemical Engineering, Mining Engineering, Metallurgy or a related field - 5+ years of experience in mining, operations, process scale-up, or plant design in minerals processing, chemicals, specialty materials, oil & gas, or related industries - Ability to design experiments, troubleshoot complex processes, and analyze operational datasets - Proven ability to utilize software and automation to improve process performance while reducing errors and resource intensity - Strong commitment to Health, Safety, and Environmental compliance - Excellent technical writing, communication, and teamwork skills - Comfortable working in fast-paced environments, wearing multiple hats, and managing ambiguity WHY JOIN US? At Mariana Minerals, you’ll be part of a mission-driven team reshaping the way critical minerals are sourced and supplied globally. You’ll have the autonomy to make big decisions, the tools to innovate, and a culture that values ownership, smart automation, and collaboration. OUR CULTURE IS BUILT ON THREE PRINCIPLES: 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. Mariana is an Equal Opportunity Employer. We celebrate diversity and are committed to creating an inclusive environment for all employees. We do not discriminate on the basis of race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, veteran status, or any other protected status.