On February 15, 2024, Peru’s National Environmental Certification Service for Sustainable Investments (SENACE) approved, after a detailed evaluation process, the Modification of the Environmental Impact Study (MEIA) of copper and zinc mining major Compañía Minera Antamina. This approval allows for an investment of approximately US$2 billion over the next few years, following Antamina’s internal governance process, which will allow the company to extend its operations from 2028 to 2036 in the Áncash region.
The MEIA will allow Antamina to optimise existing mining components within its current operation, underpinning environmental, social and operational sustainability. Among the main modifications are the expansion of the footprint of the open pit, and the expansion and optimisation of the dumps and tailings dam. These modifications have been designed under strict engineering protocols, which guarantee safe conditions for workers and adjacent communities.
As these are changes within the area of operations, the positive relationship that the company has managed to consolidate for more than 20 years with neighbouring communities and populations it says will remain unchanged. The MEIA has been the result of rigorous technical work that involved various state entities and top-level consultants. During the evaluation stage, three citizen participation processes were carried out between 2019 and 2022 in the area of social and environmental influence, incorporating cultural and diversity aspects. This made it possible to integrate valuable contributions from the public sector, communal authorities and citizens.
Víctor Gobitz, President and CEO of Antamina, thanked all parties involved in this process. “The MEIA is an important milestone for Antamina and the Peruvian mining industry, and reaffirms our commitment to the country and the Ancash region. This approval broadens our horizon and allows us to continue working hand in hand with the authorities and communities to deploy a mature public and private institutional framework, which seeks to transform economic resources from mining into sustainable development for all,” he commented.
Antamina is one of the leading copper producing companies in Peru, and one of the largest in the world; Its shareholders are BHP, Glencore, Teck and Mitsubishi.
In terms of the consultants Antamina has worked with, DRA has played an important role. Back in 2020 it was elected by Antamina to lead the Early Contractor Involvement (ECI) phase of the Waste 1 project and has continued working with Antamina on various projects since then including involvement with the Waste 2 and CCS elements of the MEIA. Stantec has also provided extensive tailings-related services to Antamina as well as preparation of the MEIA document itself.
The MEIA outlines the changes at Antamina going forward. The mine area will be increased by 25% and the open pit will be deepened by additional 150 m will be deepened. Up to 173,000 t/d of ore will be extracted, with a waste movement of up to approximately 742,000 t/d.
There will be replacement of the primary ore crushing station and installation of a new Waste 2 rock crusher. Two new tunnels will be built along with associated conveyor belts: one for ore towards the processing plant and the other (Waste 2) for waste towards a spreader at the waste dumps. The conveyor belt system will complement transportation by mining trucks, which will remain at the current levels. The Waste 1 part of the project involves optimisation of the existing waste crushing and transportation system to the waste dumps.
Specifically, the ore extracted from the pit will be taken to the crushing and ore transportation system (also called the CCS). This auxiliary facility will have modifications that will consist of the inclusion of the new primary crushing station, which will be inside a buried concrete building, and the belt hauling system that will transport and unload the ore through stackers fixed to the processing plant storage piles.
There will be a 26% increase in waste storage capacity at the Este waste dump to reach 3,840 Mt and a 32% increase at the Tucush waste dump to reach a capacity of approximately 1,280 Mt. Este’s footprint will increase by 36% to reach an approximate surface area of 1,494 ha. The optimised design for Tucush will generate an increase in the footprint by 8% to reach a total surface area of 346 ha.
At the tailings dam, 195 m will be added at the base and 30 m in height, applying a design that guarantees the safety of the infrastructure. This increases the approved elevation of 4,165 m above sea level to the elevation of 4,195 meters above sea level. The dam will reach a storage capacity of approximately 1,527 Mt from the current 1,100 Mt and the footprint will occupy an area of approximately 905 ha.
Antamina will also optimise some equipment and processes in the processing plant in the main stages of crushing, grinding, classification and flotation, to reach a capacity of 208,000 t per day and maintain the annual production volume, through the replacement, modification and/or addition of equipment in seven areas.
