McEwen’s El Gallo mine EIA extension: capex, schedule and throughput notes for engineers
Reviewed by Tom Sullivan

First reported on MINING.com
30 Second Briefing
McEwen Mining has secured Mexican federal approval to extend the environmental impact assessment for its El Gallo project in Sinaloa, clearing the way for Phase 1 mill construction targeted to start mid-2026 and first gold pour in 2027. Phase 1 of the Fenix redevelopment will reprocess material from the existing historical leach pad via a new mill and leach circuit, aiming for about 20,000 oz gold-equivalent per year over 10 years, with initial capex estimated at US$42 million. A contemplated Phase 2 would add in-situ silver deposits for an extra US$24 million, potentially extending mine life beyond the current plan.
Technical Brief
- Phase 1 reprocesses existing historical heap leach pad material via a new mill and leach circuit.
- El Gallo complex comprises multiple gold-silver deposits within a 13 km radius in Sinaloa.
- Broader land package controlled by McEwen around El Gallo totals approximately 1,700 km².
- Previous open pit operation (2012–2018) transitioned into deeper sulphide mineralisation unsuited to heap leaching.
- Since mid-2018, output has been limited to residual leaching of the former heap leach pads.
- Historic production totalled 279,000 oz gold and 134,000 oz silver, or 281,000 gold-equivalent oz.
- Average historical cash cost reported at US$655 per gold-equivalent ounce over the prior operating period.
- 2021 feasibility work used price assumptions of US$1,500/oz gold and US$17/oz silver for economics.
Our Take
With initial capital for Phase 1 of Fenix at US$42 million and incremental Phase 2 capex at US$24 million, this sits at the smaller end of project sizes in our gold–silver coverage, which typically gives operators more flexibility to phase construction or adjust to permitting and price risk in jurisdictions like Sinaloa.
The feasibility study’s base-case silver price of US$17/oz is materially below prevailing spot levels seen across recent silver-tagged items in our database, suggesting McEwen is stress-testing Fenix economics against a relatively conservative price deck.
McEwen’s recent drilling success at the Froome gold mine in Ontario (reported 4 December 2025) indicates the company is simultaneously advancing brownfield growth in Canada and restart/expansion options in Mexico, which may compete for internal capital allocation once Fenix approaches its targeted mid-2026 construction decision.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
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