Evaluación geotécnica de residuos mineros en la relavera comunitaria El Tablón, provincia de El Oro

Abstract

CONDITION FOR PUBLICATION OF PROJECT. The placement of mine tailings without compaction or hydraulic control constitutes one of the main geotechnical risk factors in tailings facilities during the operational phase, as it promotes conditions of saturation, increased pore water pressure, and static liquefaction. This project evaluated the stability of the deposition platforms of the El Tablón Community Tailings Facility, located in the canton of Portovelo, El Oro Province, considering both drained and undrained scenarios under the current operating conditions of the deposit. For this purpose, geometric surveys were carried out using drone-based photogrammetry to define the actual geometry of the platforms, together with surface tailings sampling campaigns to obtain representative samples. Laboratory tests for physical and mechanical characterization were conducted in accordance with ASTM and ISO standards, allowing the determination of geotechnical parameters. The obtained parameters and platform geometry were integrated into geotechnical models and analyzed using limit equilibrium methods with the Slide2 software. The results showed that the tailings platforms are mainly composed of silts and low-plasticity clays, with factors of safety of 1.42 under drained conditions and 0.34 under undrained conditions. It is concluded that the evaluated platforms exhibit unstable conditions and require technical measures to improve their geotechnical safety. Keywords: Tailings, Pore water pressure, Static liquefaction, Limit equilibrium, Drained condition.