Hydrometallurgical Process Engineer

About Mariana Minerals

Mariana Minerals is a software-first, vertically integrated minerals company focused on supplying the minerals critical to modern energy, AI, and defense technologies. We are committed to operational excellence, innovation, and building high-performing teams that drive measurable results.

The Opportunity

We are seeking a dynamic and experienced Hydrometallurgy Process Engineer to optimize our copper refining operations. This role encompasses the full value chain—from crushing and conveying to heap leaching, solvent extraction (SX), and electrowinning (EW). You will play a pivotal role in driving safety, production efficiency, cost reduction, and team performance at a large-scale operation (12MTPY+ ore production).

As a hands-on engineer, you will champion operational excellence, implement best practices, and foster a high-performance culture across a multidisciplinary team of 30+ professionals in operations, maintenance, and asset management. We are looking for a results-driven Metallurgical Engineer who can demonstrate a proven track record of delivering quantifiable improvements in similar environments.

Key Responsibilities

Operational Leadership & Process Optimization

• Oversee all aspects of the heap leach operation, including crushing, stacking, leaching, solvent extraction, and electrowinning, ensuring maximum process efficiency and cost-effectiveness.

• Identify and implement process improvements to enhance recovery rates, reduce downtime, and lower operating costs—backed by specific, quantifiable examples (e.g., increased PLS grade, reduced acid consumption, improved stacking methodology).

• Lead plant expansions, debottlenecking projects, and greenfield developments, demonstrating clear ROI (e.g., increased throughput, reduced maintenance costs).

• Optimize leach pad management (lift height, irrigation rates, aeration) to maximize copper recovery and minimize operational risks.

Safety & Compliance

• Foster a zero-harm culture, with a track record of safety program enhancements (e.g., reduced TRIFR, improved near-miss reporting, behavioral-based safety initiatives).

• Ensure full compliance with environmental, health, and safety regulations across all leaching and processing activities.

Maintenance & Asset Management

• Drive reliability-centered maintenance (RCM) strategies, with examples of predictive/preventive maintenance reducing downtime or extending asset life.

• Oversee maintenance planning and execution to minimize production impact (e.g., optimized crusher liner changes, conveyor belt replacements).

• Demonstrated experience with fixed plant maintenance, asset management systems (SAP, JDE), and spare parts optimization.

Team Collaboration & Culture Development

• Lead, mentor, and collaborate with large teams (30+ personnel) across operations, maintenance, and technical services.

• Provide examples of improving workforce engagement, such as:

• Implementing performance-based incentives that boosted productivity.

• Resolving labor inefficiencies through training, accountability, or workflow redesign.

• Cultivating a positive work culture that reduced turnover and improved collaboration.

Required Qualifications & Experience

• 3+ years in copper heap leach/SX/EW operations, with at least 5 years in leadership roles managing large operations teams.

• Proven track record of delivering measurable improvements—must be able to articulate specific projects where your actions led to:

• Cost savings (e.g., reduced reagent consumption, lower maintenance spend)

• Production increases (e.g., higher PLS grades, improved stacking rates)

• Safety improvements (e.g., reduced incidents, better compliance)

• Experience in greenfield/brownfield expansions, crushing/conveying optimization, or leach pad design is highly desirable.

• Strong financial acumen with the ability to justify capital projects and demonstrate clear payback periods.

• Exceptional communication and leadership skills, with a history of building high-performing teams.

Desired Skills

• Proficiency in lean mining, Six Sigma, or continuous improvement methodologies.

• Familiarity with planning software and ERP systems (SAP, Pronto).

Why Join Mariana Minerals?

• Lead a high-impact operation with direct influence on profitability and growth.

• Thrive in a dynamic, results-driven environment where innovation is recognized and rewarded.

• Enjoy competitive compensation, comprehensive benefits, and significant career growth potential.

Application Requirement

Please provide specific examples of past achievements (with metrics) in your resume or cover letter.

Ready to make a measurable impact? Apply now and help shape the future of critical minerals with Mariana Minerals.