Blue Moon Mine Preliminary Economic Assessment

Fast-tracked PEA for the Blue Moon zinc-copper project in California, delivered within three months, demonstrating a strong economic case with an after-tax NPV8% of US$244M.

    Project Profile

  • Discipline / Expertise

    Mine Engineering, Metallurgy & Process Engineering, Mineral Economics

  • Location

    Mariposa County, California

  • Commodity

    Zinc - Copper

  • Service Scope

    Scoping Study / Preliminary Economic Assessment (PEA)

The Challenge / The Scope:

The client required a fast-tracked Preliminary Economic Assessment for the Blue Moon project, a zinc-copper deposit located within a geographically constrained site in California. With an aggressive timeline of approximately three months, the goal was to develop a credible, high-quality PEA that could also support ongoing permitting and exploration planning.

Micon’s Approach:

To meet the client’s tight three-month timeline, Micon employed a focused and collaborative execution strategy. Our multidisciplinary team worked efficiently across mining, processing, and infrastructure disciplines to keep all key components moving in parallel.

For the mining scope, Micon completed MSO analysis, mining method selection, and detailed mine design using Datamine StudioUG and EPS. Long-hole stoping with paste backfill was selected as the preferred method, with a production rate of 1,800 tonnes per day. Ramp access, ventilation planning, scheduling, and portal location were all tailored to the site’s constrained footprint.

In processing, a conventional circuit was defined based on historical metallurgical testwork, including SAG and ball milling, copper and zinc flotation, and concentrate filtration. Tailings were directed to a dry-stack storage facility, with a portion used for paste backfill.

Infrastructure planning addressed power supply from a nearby hydroelectric source, water recycling systems, and road upgrades. The design emphasized environmental protection, operating efficiency, and compatibility with future permitting and development phases.

Results:

The Preliminary Economic Assessment was delivered on schedule, highlighting a compelling economic case for the Blue Moon deposit, with an After-Tax NPV8% of US$244M, and an After-Tax IRR of 38%. Beyond the core deliverable, Micon continued to support the client with technical guidance for permitting processes and facilitated engagement with a contractor for a follow-up exploration development program.