Strikes, severe weather, accidents and geological problems put an average 5.2% of production at Chile’s largest copper mines at risk, according to a new assessment that suggests almost one in 10 tonnes could be vulnerable at the country’s most exposed operation.
GEM Mining Consulting’s first Production-at-Risk Index assessed 14 major copper operations across eight threats, with scores ranging from 2.6% to 9%. El Teniente ranked highest at 9%, followed by Los Pelambres at 8% and Escondida at 7.5%. Nine operations carry at least one risk rated high.
The results come after a turbulent few months for the world’s largest copper-producing country. Workers at Antofagasta’s (LON: ANTO) Centinela began an indefinite strike this week, BHP’s (ASX: BHP) Escondida shut after a fatal accident and storms disrupted Los Pelambres and Caserones. Codelco also suspended its Andes Norte project at El Teniente over deep seismic risks.
The index attempts to quantify a problem that production forecasts can obscure: mine plans generally assume operations proceed largely as expected, even though labour disputes, weather, accidents, geology and processing problems routinely interrupt output.
Chile produced 9.3% less copper from January through July than during the same period in 2025, while July output sank to its lowest monthly level since 2011, the Santiago-based consultancy said.
Risks converge
The highest-risk operations stand out because multiple vulnerabilities overlap rather than because of any single threat. At El Teniente, high geotechnical and safety risks combine with four medium-rated categories, while Los Pelambres carries high weather and water exposure. Escondida has high ratings for both labour and safety.
Centinela’s labour risk is also rated high, with more than 700 workers walking off the job on Oct. 7 after mediation overseen by Chile’s Labour Inspectorate failed to resolve the dispute. Metallurgy and ramp-up risks are rated medium.
Lundin Mining’s (TSX: LUN) Caserones carries a high weather rating, showing that a mine does not need several high-risk categories to face a meaningful threat to planned output.
At the other end of the assessment, Radomiro Tomic, Spence and Ministro Hales have no risks classified as high. The contrast shows that Chile’s production risk is concentrated unevenly across its major mines rather than shared equally.
Measuring disruption
GEM calculates production at risk using expected losses across eight categories: labour, water, weather, geotechnical conditions, metallurgy and grades, ramp-up performance, safety and permitting.
Each operation receives a low, medium or high rating based on public evidence from 2025 and 2026. A high rating represents an expected production loss of 3%, or roughly 11 days of annual output. Medium risk corresponds to 0.75%, or about three days, while low risk represents 0.19%, or less than a day.
The model compounds the eight risks rather than simply adding them, reflecting the amount of production remaining after each potential loss. GEM said future versions are expected to replace the ratings with probabilities and severity estimates derived from individual mines’ operating histories.
Labour and metallurgy and grades are the biggest contributors to the index, averaging 0.83 percentage points of production at risk apiece. Weather and safety follow at 0.79 percentage points each.
Other operations demonstrate how different vulnerabilities can produce similar levels of exposure. Collahuasi’s metallurgy and grades risk is rated high after its ore grade fell to 0.90% from 1.15%, contributing to a 27% production decline in 2025. Chuquicamata carries high safety risk after restrictions following an accident contributed to a 13% production decline, while Quebrada Blanca faces high ramp-up risk as construction of its tailings storage facility constrains production.
Gabriela Mistral carries high metallurgy and grades risk after geological factors contributed to a 20% output decline.
The index is an exposure measure rather than a forecast that 5.2% of production will necessarily disappear. Its ratings are based on standardized expected losses and public evidence rather than mine-specific probabilities, meaning an identified risk may never materialize while a disruption outside the framework still could.
Even so, the assessment shows why headline production capacity can differ from dependable supply. On GEM’s calculations, roughly one in every 20 kilograms of copper expected from Chile’s largest operations depends on the eight identified risks not disrupting output. At El Teniente, the exposure approaches one in 10.
With Centinela workers now on strike and operational risks accumulating across several of Chile’s biggest mines, the gap between planned and delivered copper remains a threat to a market dependent on the country’s supply.
