Bajo La Alumbrera

Bajo La Alumbrera
Name	Bajo La Alumbrera
Location	Andalgalá Department, Catamarca Province, Argentina
Coordinates	27°2′S 66°24′W
Owner	Minera Alumbrera Limited (Glencore, Goldcorp, Yamana)
Products	Copper, Gold
Opening year	1997
Closing year	2018 (processing); decommissioning ongoing

Bajo La Alumbrera Bajo La Alumbrera was a large open pit copper and gold mine in the Andalgalá Department of Catamarca Province, Argentina, developed as a joint venture among multinational corporations and operated from the late 1990s into the 2010s. The project attracted attention from regional governments, indigenous communities, environmental organizations, and international investors because of its scale, metallurgical output, infrastructure such as tailings facilities and pipelines, and the controversies over water resources and environmental compliance. The site linked to broader debates involving extractive industries in Latin America, corporate governance, and transnational litigation.

Overview

The project was located near Andalgalá, within Catamarca Province, in the Argentine Northwest, and consisted of an open pit with associated processing plants, waste rock dumps, tailings storage, access roads, and a pipeline corridor to the Choya River basin. Ownership and financing involved multinational entities including Glencore, Goldcorp, and Yamana Gold through a consortium structure that attracted capital from global markets such as the Toronto Stock Exchange and London Stock Exchange. Regional administration and oversight included bodies from Argentina and provincial authorities, while civil society scrutiny came from organizations like Greenpeace, Amnesty International, and local NGOs. The deposit was mined for both copper and gold, contributing to Argentina's mineral exports and engaging companies experienced in projects such as El Teniente, Los Pelambres, and Cerro Negro.

History and Development

Exploration in the area increased during the 1980s and 1990s with interest from firms active in South America including those previously involved at Yanacocha, Pascua-Lama, and Escondida. The project advanced through feasibility studies, permitting, and infrastructure construction in the mid-1990s, aligning with investment patterns seen in international projects like Lagunas Norte and Oro Plomo. Construction included development of processing circuits and tailings facilities, financed by international banks and insurers with involvement from entities similar to Export Development Canada and private equity groups. Local political actors in Catamarca Province and national ministries participated in approvals analogous to processes at Atacama projects, while community engagement mirrored disputes seen at Potosí and Cochabamba.

Geology and Mineralization

The deposit was an epithermal to porphyry-style system within the geological framework of the Andean orogeny and the Argentine Northwest metallogenic belts. Mineralization included chalcopyrite and bornite alongside native gold and electrum, comparable to mineral assemblages at Chuquicamata and El Indio. Host rocks and alteration zones related to intrusive events akin to those documented at Sierra Gorda and Altiplano provinces, with structural controls similar to fault systems studied near Famatina and Sierras Pampeanas. Geochemical and isotopic work paralleled investigations undertaken at Los Azules and Zafranal to characterize sulfide distribution, alteration halos, and weathering profiles relevant to open-pit extraction methods.

Mining Operations and Production

Operation phases included conventional open-pit blasting, haulage, comminution, flotation, and concentrate handling, producing copper and gold concentrates destined for smelters in regional hubs like Antofagasta and global markets in China and Japan. Equipment suppliers and contractors resembled suppliers used at projects such as Barrick Gold sites and BHP operations, and production reporting followed standards akin to those of the JORC Code and NI 43-101. Workforce composition reflected local hiring combined with specialist teams from companies with experience at Marcona and Tocopilla, and logistics included rail and road links comparable to corridors serving Salta and Jujuy mining projects.

Environmental and Social Impact

Concerns were raised about water use, tailings management, and impacts on riparian systems and agricultural lands, echoing disputes at Pueblo Viejo and Esquel. Local communities, including indigenous and rural populations near Andalgalá and upstream users on rivers comparable to the Choya River basin, protested potential contamination and depletion risks; advocacy groups and legal defenders drew parallels with cases involving Indigenous peoples rights and environmental litigation in Latin America. Environmental monitoring, remediation plans, and corporate social responsibility measures were compared to standards applied at sites like Río Tinto projects and projects with oversight by organizations similar to the World Bank and International Finance Corporation.

Legal Issues and Controversies

The project generated litigation and administrative disputes involving provincial regulators, national courts, and international forums, with allegations related to water contamination, permitting, and compliance that mirrored legal battles at Pascua-Lama and Yanacocha. Civil society campaigns mobilized under coalitions resembling Friends of the Earth and local assemblies, leading to injunctions, appeals, and enforcement actions by provincial authorities and national environmental agencies. Corporate defense strategies invoked contractual protections, investor-state dispute paradigms used in cases before bodies like ICSID, and precedents from arbitration related to mining investment disputes in Chile and Peru.

Closure and Rehabilitation

Commercial operations wound down in the 2010s as ore grades declined and processing ceased, prompting long-term closure planning similar to decommissioning at Los Pelambres and El Teniente. Rehabilitation efforts have involved tailings stabilization, water treatment systems, progressive reclamation, and monitoring regimes consistent with best practices applied at sites certified by environmental programs associated with ISO standards and multilateral guidelines from institutions akin to the Inter-American Development Bank. Ongoing debates persist over financial assurance, community restitution, and monitoring responsibilities comparable to post-closure discussions in other Andean jurisdictions.

Category:Copper mines in Argentina Category:Gold mines in Argentina Category:Catamarca Province