---
title: 'Pilot Plant Technician (Night Shift) at Mariana Minerals'
canonical: 'https://feeny.ai/job/pilot-plant-technician-night-shift-mariana-minerals-san-francisco-xt80rkhtfgne'
type: 'job'
last_seen: '2026-09-04'
---

# Pilot Plant Technician (Night Shift) at Mariana Minerals

- **Company:** Mariana Minerals
- **Location:** San Francisco, CA
- **Compensation:** $35–$45/hr
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2026-09-01
- **Last confirmed live:** 2026-09-04
- **Apply:** https://jobs.ashbyhq.com/marianaminerals/8ca25251-ed4b-4929-94f1-6aa718e06dc4

## Job description

## 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.

## ROLE OVERVIEW

Mariana Minerals is looking for a highly motivated technician to join our San Francisco Pilot Plant team on the night shift. You will support the design, deployment, and operation of first-of-its-kind refining processes for critical minerals, while also supporting development of software for automated plant optimization. This position is highly hands-on and will play a critical role in bridging R&D and Operations, ensuring processes are robust, safe, cost-effective, and suitable for commercial production.

## POTENTIAL SCHEDULE

- Front End Nights: 6:00pm – 6:00am Sunday thru Tuesday/Wednesday
- Back End Nights: 6:00pm – 6:00am Wednesday/Thursday thru Saturday

## WHAT YOU’LL DO

- Assist engineers and other technicians to operate and monitor copper extraction chemical processes
- Safely handle chemicals, raw materials, and waste streams in compliance with SOPs and regulations
- Support sampling, quality checks, and basic laboratory measurements
- Assist with design, install, startup, and commissioning of new equipment and processes
- Take ownership of plant cleanliness and organization, ensuring work areas, tools, and equipment are well-maintained and ready for operations
- Perform routine maintenance, inspections, and basic mechanical repairs; document findings & actions in a Computerized Maintenance Management System (CMMS)
- Create and maintain procedures, experimental records, shift reports, and other critical operations documents

## WHAT YOU’LL BRING

- Associate degree, technical certificate, or equivalent experience in chemical technology, process technology, industrial operations, or a related field
- Experience operating pilot plant or commercial scale industrial equipment in the minerals processing, chemicals, specialty materials, oil & gas, biotech, or similar industry
- Prior exposure to core plant safety work processes such as Lockout/Tagout (LOTO), hot work permitting, confined space entry, and safe work permitting systems
- Experience using human–machine interfaces (HMIs) and plant software systems to monitor, control, and adjust process operation
- Experience with hands-on equipment installation, modification, and troubleshooting
- Basic knowledge of inorganic chemistry, pH, and reaction stoichiometry a plus
- Experience using engineering documents such as PFDs, control narratives, or P&IDs is a plus
- Climb stairs, stand for extended periods of time, and safely lift up to 50 lbs

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!

## About Mariana Minerals

## Company Overview
- **One-liner**: Mariana Minerals is a software-first, vertically integrated minerals company focused on supplying the minerals critical to modern energy, AI, and defense technologies.
- **Entity Type**: Private (Series A, $85M funding in July 2025)
- **Headquarters**: San Francisco, California, United States
- **Founded**: Not publicly available
- **Founders**: Turner Caldwell (Co-Founder & CEO)

## Core Business
- **Primary industry**: Metal Ore Mining / Critical Minerals
- **Target customers**: B2B – energy, AI, and defense supply chains (including downstream manufacturers and government entities)
- **Mission or purpose**: "Create a future of critical mineral abundance" by reimagining the global minerals supply chain with software, automation, and data-driven decision making.

## Products & Services
- **Copper One (formerly Lisbon Valley Copper Mine)**: World’s first autonomous mine, located in Utah. Produces copper using integrated automation and software control. Restarted production in April 2026.
- **Lithium One**: Lithium project (on the roadmap or early development).
- **Other mineral projects**: Graphite, Uranium, Rare Earth Metals, Cobalt, Nickel, Aluminium – at various stages (stealth or roadmap).
- **CapitalProjectOS**: Internal software platform for capital project management (mentioned in leadership bio).
- **Technology Stack**: React, dbt, TypeScript, Python, TensorFlow, PyTorch, microservices, SCADA, Autodesk, and many others – indicating a strong software engineering backbone.

## Market Standing
- **Valuation/Market Cap**: Not disclosed (private company)
- **Key Metric**: Total funding – $85M Series A (July 2025, 1 investor)
- **Notable Investors/Partners**: Lead investor not publicly disclosed (Andreessen Horowitz was pitched but not confirmed as an investor). Partners include Bot Auto, WeRide, Pronto, Atoms (based on LinkedIn mentions). Also works with UMA (Utah Mining Association).
- **Growth Signals**: Headcount grew 3,575% YoY to 107 employees (as of mid-2026). 73 active job postings. Opened the world’s first autonomous mine (Copper One) in April/May 2026, generating significant industry news and social media engagement.

## Competitive Advantages
- **Software-first approach**: The company builds automation and data systems from the ground up, rather than layering tech onto legacy mining operations. This enables fully autonomous mining.
- **Vertical integration**: They develop, own, and operate mineral projects, controlling the entire value chain from extraction to processing.
- **Deep tech stack**: Use of AI/ML (TensorFlow, PyTorch), simulation, and real-time control systems to optimize mining operations.
- **First-mover in autonomous mining**: Copper One is claimed to be the world’s first autonomous mine, giving them a significant lead in operational efficiency and safety.

## Strategic Focus
- Scale autonomous mining operations beyond copper (lithium, graphite, uranium, etc.)
- Secure domestic supply of critical minerals for U.S. energy, AI, and defense needs.
- Continue aggressive hiring across engineering, operations, and field roles.
- Expand from Utah to additional sites (Houston engineering office, potential new projects).

## Why Work Here
- **Culture principles**: "Extreme Ownership", "Engineer Out Requirements, Then Automate", "Share Your Legos" – emphasizing accountability, simplification, and collaboration.
- **Work environment**: High-growth startup with a mission-driven focus on critical infrastructure. Offices in San Francisco (HQ), Houston (Engineering), and La Sal, Utah (mine site). Hybrid/remote policy not explicitly stated, but multiple office locations suggest flexibility for field vs. office roles.
- **Notable perks**: Opportunity to work on cutting-edge autonomous systems and AI in a traditional industry. Strong engineering culture with modern tech stack (React, Python, ML). Rapid career growth due to company expansion.
- **Talent sources**: Attracts talent from Tesla, Redwood Materials, Lilac, ExxonMobil, Amazon Web Services, and other tech/energy companies – indicating a high-caliber peer group.

## Sources
1. [marianaminerals.com](https://marianaminerals.com/)
2. [marianaminerals.com/careers](https://marianaminerals.com/careers)
3. [marianaminerals.com/about](https://marianaminerals.com/about)
4. [jobs.ashbyhq.com/marianaminerals](https://jobs.ashbyhq.com/marianaminerals)
5. [linkedin.com/company/mariana-minerals](https://www.linkedin.com/company/mariana-minerals)

## Other roles at Mariana Minerals

- [Sr./Staff Technical Program Manager - Copper](https://feeny.ai/job/sr-staff-technical-program-manager-copper-mariana-minerals-moab-hybc9rnj2271) — Moab, UT
- [Mechanical Engineer](https://feeny.ai/job/mechanical-engineer-mariana-minerals-san-francisco-dv7an46y7ypw) — San Francisco, CA
- [Full Stack Software Engineer](https://feeny.ai/job/full-stack-software-engineer-mariana-minerals-san-francisco-tdera62xv3p5) — San Francisco, CA
- [Administrative Assistant](https://feeny.ai/job/administrative-assistant-mariana-minerals-houston-bamf8ahyve5k) — Houston, TX
- [Senior Systems Administrator](https://feeny.ai/job/senior-systems-administrator-mariana-minerals-san-francisco-t93c8xavrzp1) — San Francisco, CA
- [Lead Operator](https://feeny.ai/job/lead-operator-mariana-minerals-east-6239emcdyrrk) — East, TX
- [Lab Chemist](https://feeny.ai/job/lab-chemist-mariana-minerals-moab-3s3trq9bcdc4) — Moab, UT
- [Controls Technician](https://feeny.ai/job/controls-technician-mariana-minerals-east-kt73j4cf89md) — East, TX
- [Maintenance Technician](https://feeny.ai/job/maintenance-technician-mariana-minerals-east-am22rcspy7bp) — East, TX
- [Process Engineer](https://feeny.ai/job/process-engineer-mariana-minerals-east-en510gjggana) — East, TX