We have contributed in the state of Chihuahua with a tailings dam closure project. The scope included baseline definition, dam safety review, critical basic technical studies and closure engineering of the tailings dams. From the beginning of the project, our team performed a thorough review of all available information on the mining unit. This detailed analysis allowed us to identify key opportunities to improve the closure design of the tailings dams and optimize the CAPEX of the closure works.
Thanks to our multidisciplinary approach and our technical experience, Anddes carried out the baseline evaluation of the tailings dams, which was carried out by a specialized technical team composed of civil, geotechnical, hydraulic and environmental engineers. The work included a technical inspection of the facilities to verify the geotechnical conditions, water management, operability and safety, applying international standards such as the Mining Association of Canada guide. Engineering reports, hydraulic studies, geotechnical studies, as-built data, closure and water management plans were also reviewed. After the evaluation, recommendations, corrective actions and a work plan for future stages were presented.
The Dam Safety Review (DSR) of the tailings dams was carried out taking into account the guidelines of the Application of Dam Safety Guidelines to Mining Dams (2014) and the Technical Bulletin: Dam Safety Review (2019) of the Canadian Dam Association (CDA).
The basic studies included several key activities, such as geotechnical evaluation and supervision of technical and environmental studies. As part of the geotechnical evaluation, geological-geotechnical mapping was carried out to identify relevant features such as faults, organic soils, and zoning of geotechnical units, ensuring a comprehensive understanding of the geology and site conditions; Likewise, comprehensive investigations were carried out including the supervision of drilling, geotechnical tests (SCPTu, drilling, test pits), material sampling and a robust laboratory testing program to determine the physical and mechanical properties of the soils. These studies provided critical information for characterizing soil behavior and the stability of the tailings dams.
All these studies provided a comprehensive view of the conditions of the tailings dams, which made it possible to provide the necessary recommendations to ensure their stability and proper management in the future.
Likewise, the feasibility-level closure engineering was developed, Anddes carried out the preliminary design of the tailings dam closure. Preliminary design alternatives were proposed, design criteria were defined, stability analyses and civil and hydraulic design were performed, as well as the design of the cover for the two dams. A solid CAPEX estimation was also carried out, which will serve as a basis for future planning and strategic decision making. Throughout this process, we have ensured that each recommendation is aligned with the highest standards of technical feasibility.
Anddes successfully completed all key activities efficiently and in line with the objectives proposed by our client. A rigorous approach was followed in each of the stages, from the initial geotechnical studies to the development of the closure feasibility engineering. The drilling, geotechnical tests, and geophysical studies provided the technical information necessary for an adequate geotechnical characterization of the tailings dams. The project was executed within the estimated timeframes, ensuring a technically feasible solution for the closure of the tailings dams, complying with international safety and sustainability standards.