Gualcamayo Mine
Client
Minas Argentinas S.A.Location
San Juan, ArgentinaHighlights
- Stability studies for slopes, waste rock dumps, and heap leach pads
- Detailed assessment of the liquefaction potential of the heap leach pads
- Detailed engineering for the original North Pad, the final section of the ore conveyor, and the North Valley expansion to increase production capacity
- Development of barren solution pumping and pregnant leach solution recirculation systems
- Environmental management plans and environmental impact reports
Overview
Minas Argentinas S.A. (MASA) began exploring the Gualcamayo deposit in 1994. The deposit is located in the northwestern part of Jáchal Department, approximately 270 km from the city of San Juan and 110 km from the city of San José de Jáchal. The Gualcamayo Mine (Gualcamayo) was built in 2007 and began production in 2009.
Located within a mining district spanning more than 38,000 hectares, the project covers 7,128 hectares and reaches a maximum elevation of 2,500 meters above sea level, with the camp at 1,600 meters above sea level. Disseminated gold mineralization occurs primarily in the Quebrada del Diablo area and extends into the adjacent Amelia Inés and Magdalena areas.
The operation recovers residual gold by re-leaching ore that was previously mined, crushed, and placed on the heap leach pads. The final product consists of doré bars containing gold and silver, which are exported for refining and sale.
The Deep Carbonates Project (DCP) involves the construction of a new underground mine and a new processing plant using pressure oxidation. The refractory gold deposit lies beneath Gualcamayo’s oxide gold mineralization. The project, which was submitted and approved under Argentina’s Large Investment Incentive Regime (RIGI), has a planned investment of US$665 million. The DCP is currently progressing through the prefeasibility and feasibility stages.
Knight Piésold has completed more than 40 consulting assignments for Gualcamayo, supporting its development through geotechnical studies, detailed engineering, and environmental services:
- From the early stages, the work included stability studies for slopes, waste rock dumps, and heap leach pads, as well as a detailed assessment of the liquefaction potential of the heap Leach pads. These assessments informed the design and operation of the facilities.
- Detailed engineering work included the original North Pad, the final section of the ore conveyor, and the North Valley expansion. Knight Piésold also developed solutions for pregnant leach solution (PLS) recirculation and barren solution pumping, contributing to the efficiency of the leaching process.
- Environmental support included monitoring plans, emissions assessments, revegetation, and updates to environmental impact reports as part of the management of operational impacts.
The Challenge
Gualcamayo’s development requires integrating geotechnical stability, leaching system efficiency, and compliance with environmental requirements, while adapting engineering solutions to operational needs and increased production capacity.
The DCP presents new challenges associated with the design of the new underground mine and processing plant, as well as the implementation of suitable pressure oxidation technology for ore treatment through the installation of South America’s first plant of this type.
Efficient water management is another key consideration, given the region’s arid conditions and the need to optimize the use of water resources.
Our Approach
Knight Piésold has been supporting Minas Argentinas with engineering and environmental solutions tailored to Gualcamayo’s different stages and development objectives.
From the early stages, the work focused on assessing the stability of geotechnical structures and providing criteria for their design and operation. Studies of slopes, waste rock dumps, and heap leach pads, together with the assessment of the liquefaction potential of the heap leach pads, helped identify improvements to support safety and operational continuity.
As the project evolved, detailed engineering supported the development of leaching and ore-conveying infrastructure. The designs for the North Pad, the final section of the ore conveyor, and the North Valley expansion addressed operational needs, as did the solutions for PLS recirculation and barren solution pumping.
This work was complemented by environmental studies and management tools to support permitting and updates to environmental impact reports.
As Gualcamayo enters new stages of development, Knight Piésold aims to continue contributing its expertise to develop solutions that meet the project’s technical and environmental requirements.
The Results
The environmental studies completed by Knight Piésold contributed to the permitting process and to the approval of the permits required for the continuity of the project.
Engineering designs were adapted to Minas Argentinas’ requirements and evolving operational needs. The assessment of geotechnical structures and the development of leaching systems helped optimize stacking and processing capacity and support Gualcamayo’s operational continuity.
The experience gained across these consulting assignments provides a foundation for supporting Gualcamayo’s upcoming challenges and delivering solutions for its next stages of development.