Warehouse Supervisor - Reagents & Bulk Materials

Warehouse Supervisor
- Reagents & Bulk Materials

Full Time Mountain Pass, CA, US

4 days ago Requisition

Salary Range: $90,000.00 To $ Annually

MP Materials (NYSE: MP) is rebuilding American industrial capability for a new era of autonomy, robotics, and electrification.

We are the only U.S. company with a fully integrated rare earth supply chain—from mining and refining to advanced metal and magnet manufacturing. Our products include both the critical materials used to make permanent magnets and the finished magnets themselves—enabling next-generation technologies in robotics, automation, aerospace, transportation, defense, and energy systems. These materials are the foundation of physical AI—the convergence of computation, movement, and control.

We hire ambitious, mission-driven people who want to tackle complex challenges and shape the future of strategic industries. Our culture is rooted in teamwork, resiliency, and integrity, with a deep commitment to operational excellence and national purpose. MP is rapidly evolving from a materials producer into a leading U.S. manufacturer—and our people are driving that transformation.

Position Overview:

The Warehouse Supervisor – Reagents & Bulk Materials provides end-to-end operational ownership of reagent and bulk material flow at the Mountain Pass facility. This role is responsible for driving strict safety compliance, inventory traceability, material availability, and process discipline. Based physically within one of the reagent warehouses, this supervisor oversees a dedicated team of operators ensuring operational efficiency and full alignment with company policy.

The supervisor establishes clear operational ownership to support scalable, incident-free 24/7 warehouse operations.

• Deliver accurate SAP / ERP system transactions to maintain inventory integrity. Enforce a same-day receiving standard to eliminate material backlogs and ensure processing occurs within defined time frames.
• Maintain full alignment with Sarbanes-Oxley (SOX) compliance, safety mandates, and environmental expectations to deliver incident-free operation.
• Perform precise validation checks comparing Purchase Orders (PO) vs. Bills of Lading (BOL) vs. physical material. Coordinate and communicate with Accounts Payable (AP) to ensure tight Goods Receipt (GR) vs. invoice validation.
• Ensure all inbound materials are labeled immediately upon receipt with the PO number, material number, quantity, and date.
• Partner with operations for daily reagent deliveries on kanban system and accurate allocation of consumed materials.
• Support site inventory control activities, including cycle counts, variance investigations, and authorized stock adjustments. Ensure all material or paperwork discrepancies are identified immediately at the point of receipt.
• Serve as the subject matter expert for reagent and bulk materials management activities and requirements, and other duties as assigned.
• Lead daily receiving activities and monitor workloads ensure the success of the crew.
• Act as a supportive and inspirational leader who can work independently with a high sense of urgency in a hands-on, active industrial team environment.

• Bachelor’s degree in business, logistics, supply chain, or related field. Or 5 years of progressive experience in warehouse operations in an industrial environment.
• Proven ability to lead teams, manage shift schedules, assess individual capabilities, and enforce strict team discipline and execution.
• Minimum 3 years of experience supervising/managing warehouse operations.
• Strong experience with ERP and MRP systems. SAP is a plus.
• Direct experience operating in a mining, refining, chemical processing, or construction environment preferred.
• Solid working knowledge of industrial environmental health and safety standards, safety data sheet (SDS) compliance, and OSHA/DOT guidelines applying to hazardous materials handling and storage.
• Advanced computer skills including Microsoft Office. Ability to operate forklifts and obtain required operating certifications if needed.

MP Materials is Proud to be an Equal Opportunity / Affi

All qualified…