Search Results (108)

Mining-induced land subsidence poses significant geohazard risks to critical on-site mining operational support infrastructure, such as tailings storage facilities (TSFs). This study investigates the Doornpoort TSF subsidence at the South Deep gold mine in South Africa, using multi-temporal Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) and Non-negative Matrix Factorisation (NMF) algorithm approach to split the superimposed subsidence contributing drivers, alongside the incorporation of Global Navigation Satellite System (GNSS) data and underground mining layout plans. 78 Sentinel-1A Satellite Aperture Radar (SAR) ascending acquisitions between May 2022 and December 2024 were obtained and processed to determine the average annual deformation rates and cumulative time-series displacement for the study area. The InSAR-derived subsidence rates at the designated three benchmarks on the embankments of the Doornpoort TSF and TSF 1&2 are −26.09 mm/year, −13.40 mm/year and −16.25 mm/year, while the maximum cumulative subsidence was −57.45 mm, −42.76 mm and −36.44 mm. A comparison of the InSAR results with the GNSS-derived subsidence results showed correlation standard deviations of 1.87 mm, 0.93 mm, and 1.05 mm, respectively. The InSAR results revealed spatially coherent subsidence patterns and a good correlation between deformation boundaries and underground mining layouts, suggesting that mining-induced stress redistribution is the primary driver of regional surface subsidence. The NMF decomposition of the InSAR-derived deformation result at a selected benchmark on the Doornpoort TSF embankment, whose average annual deformation with a cumulative time series deformation of −26.09 mm/year and −57.45 mm, respectively, revealed that 92% of the observed cumulative deformation is associated directly with the underground mining, whilst the remaining 8% is associated with TSF embankment consolidation. Furthermore, the selected decomposition benchmark within the TSF basin showed that underground mining alone accounted for 100% of the observed subsidence there. These findings support a coupled deformation framework in which deep mining activities influence regional subsidence, while localised geological conditions modulate its surface manifestation. Full article

The phreatic surface and seepage field are key factors causing instability in tailings storage facilities (TSFs). In this study, electrical resistivity tomography (ERT) was used to determine the internal structure and phreatic surface of the TSF of Husab Mine. The seepage pathways at the southeast and northwest corners of the TSF were identified and the seepage mechanisms were analyzed. In order to discharge the slurry, outlets equipped with valves were installed on the tailings embankment. During the deposition process, time-lapse electrical resistivity tomography (TL-ERT) was conducted to monitor the infiltration of water around the W13 outlet. The results show that the tailings sediments were divided into three layers based on resistivity values. The top layer consisted of shallow, unsaturated tailings material, while the middle layer comprised saturated tailings material. The thickness of the saturated zone gradually increased from the dam toward the decant pool. The bottom layer consisted of the geomembrane liner and natural sediments. Two seepage locations, named the Lebusa corner and Alister corner, were located at the southeast and northwest corners of the TSF, respectively. Seepage occurred because clarified water originating from the decant pool migrated through the saturated zone of the tailings pond, along the base of the tailings embankment. Upon encountering the starter dam, the water was impeded and subsequently emerged as seepage at the junction between the starter dam and the tailings embankment. TL-ERT monitoring shows that the extent of increased moisture was approximately 60 m horizontally and roughly 10 m vertically due to deposition at the W13 outlet. Full article

Background: The impact of long-term residence in uranium legacy-affected areas on surgical outcomes in patients with lower extremity artery disease (LEAD) remains insufficiently studied. Objectives: This study aimed to compare early postoperative dynamics of chronic lower limb ischemia (CLLI) in patients with LEAD residing in uranium legacy-affected areas and those living outside the zone of potential technogenic exposure. Methods: The study included 70 patients with LEAD (CLLI stages IIB–IV according to the Fontaine classification). The study group (n = 35) consisted of patients who had resided for at least 5 years within a radius of less than 20 km from uranium tailings storage facilities (Stepnogorsk area, Akmola region, Kazakhstan). The control group (n = 35) comprised patients with the same diagnosis living outside this zone. Results: The distribution of Fontaine stages was compared between groups before surgery and at 1 month postoperatively. Statistical analysis was performed using Pearson’s chi-squared test. Before surgery, no statistically significant intergroup differences were found in the distribution of CLLI stages (χ² = 3.688, df = 2, and p = 0.158). At 1 month after surgery, the control group demonstrated significantly better regression of ischemia stages: mild stages (I–IIa) were observed in 51.4% of control patients versus 8.6% in the study group, while severe stages (III–IV) persisted in 62.8% of the study group versus 22.9% of the control group (χ² = 17.547, df = 4, and p = 0.002). Complete regression to stage I occurred only in the control group (2 patients, 5.7%). Conclusions: Patients with LEAD residing long-term in uranium legacy-affected areas showed less favorable early postoperative dynamics compared to patients living outside the zone of potential technogenic exposure. The observed association requires cautious interpretation, and further prospective studies with individual exposure assessment are warranted. Full article

Rapid increase in mining activities, outdated management approaches, and climate change pose risks to the safe operation of mines. We explore public databases on mine tailings storage facilities (TSF) in Kazakhstan, a major mineral producer. We proceed to an in-depth analysis of a representative TSF, located in an area that has been affected by spring flooding. Our geospatial analysis and review of company reports reveal serious challenges related to the TSF design, tailings deposition patterns, and changing weather conditions. Despite modifying the TSF design in response to its failure, the company has struggled with persistent TSF overtopping and seepage in the subsequent years. Our findings from both the country-level review of TSF and the case study highlight the urgency of adopting best practices of TSF management. Specifically, our study demonstrates that risks stemming from spring flooding in Kazakhstan call for proactive TSF management, transparency, and stakeholder engagement. Such changes in TSF governance are essential for achieving a number of Sustainable Development Goals, in particular, SDG 12 Responsible Consumption and Production and SDG6 Clean Water and Sanitation. Full article

Natural lateral particle segregation commonly occurs during the hydraulic deposition of slurry and thickened tailings in surface tailings storage facilities (TSFs), producing spatial heterogeneity in physical, hydrogeotechnical, and mineralogical properties, as well as in the water table. In sulfide-rich tailings, such heterogeneity complicates the design of reclamation cover systems, which are themselves affected by it. This study investigates the impact of physical and rheological properties of hard-rock mine tailings slurries on their segregation under hydrodynamic conditions. It proposes a multiparametric equation for the segregation index (SI) based on Buckingham’s π theorem. For this purpose, six flume experiments were conducted using tailings with initial solid mass concentrations of 63%, 66%, and 69% at slopes of 0.5% and 1%. Results revealed strong exponential correlations (R² > 0.95) between SI and tailings’ physical properties (solid concentration, bulk density) as well as rheological parameters (Herschel–Bulkley yield stress and flow index, Cross infinite dynamic viscosity). The SI equation was developed using MATLAB R2025b nonlinear least-squares optimization with a trust-region reflective algorithm. Using an SI threshold of 0.05 to define non-segregating behavior, the proposed model can predict segregation tendencies as a function of tailings properties and slope conditions. Further laboratory and field investigations are needed to validate and generalize the criterion. Full article

Tailings storage facility (TSF) failures have caused severe casualties and economic losses. This study used Enhanced Small Baseline Subset InSAR (E-SBAS-InSAR) and 88 Sentinel-1A images to retrieve the 2022–2024 surface deformation time series of the Shiguilong TSF, located in the Fe–Cu polymetallic metallogenic belt of the middle–lower Yangtze River. The reliability of the results was assessed through consistency comparisons with Small Baseline Subset InSAR (SBAS-InSAR) and Persistent Scatterer InSAR (PS-InSAR). A time-series decomposition model was applied to extract seasonal deformation components and analyze their lagged responses to temperature and intense rainfall events. The results show that: (1) E-SBAS-InSAR achieved a monitoring-point density nearly 7 times higher than SBAS-InSAR, enabling dense and long-term deformation characterization; (2) subsidence at Shiguilong continued to increase, with cumulative subsidence reaching −76.8 mm and a maximum annual mean subsidence rate of −22.78 mm/yr; (3) deformation was mainly controlled by long-term consolidation of loose tailings and creep of dam–tailings materials, while seasonal factors induced stage-dependent fluctuations; (4) seasonal deformation showed lagged responses of 6 days to temperature variations and 2 days to intense rainfall events, with rainfall exerting a more pronounced influence. This work is significant for TSFs monitoring under complex surface conditions. Full article

Ground deformation monitoring is critical for safety and environmental management in modern mining. Active mining sites are highly exposed to terrain instabilities and subsidence, risking infrastructure integrity, disrupting operations, and posing hazards to communities. In this context, Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques provide an effective and non-invasive tool capable of detecting millimetric surface displacements. This study implements the Small Baseline Subset (SBAS) technique through an open-source workflow based on the Python package hyp3_sbas, enabling semi-automated and reproducible interferometric processing by combining HyP3 with MintPy. The workflow is applied to the Björkdal gold mine (Sweden), a pilot site of the Horizon Europe XTRACT project focused on enhancing resilience in critical raw material supply chains. Integrating Sentinel-1 viewing geometries resolves the true vertical deformation field, yielding an overall mean velocity of −3.99 mm/year across the mining complex, with significant displacement rates concentrated below the 25th percentile (Q1) at −11.07 mm/year. Sector-specific analysis reveals localised subsidence accelerating over underground footprints and tailings storage facilities (mean velocities of −6.56 and −3.98 mm/year; Q1 thresholds near −13.00 mm/year), contrasting with the geomechanical stability observed at the open-pit area (mean: −0.45 mm/year). The proposed open-source framework shows strong potential for operational satellite-based monitoring, supporting predictive maintenance and early-warning strategies for risk management in mining environments while simplifying and standardising the interferometric processing workflow. Full article

This study presents an integrated approach for the processing of technogenic tailings from the Balkhash concentrator, combining hydrocyclone classification, microfluidic separation, bioleaching, and geopolymer synthesis. The tailings are characterized by a fine-dispersed silicate matrix and low concentrations of valuable metals, which limit the efficiency of conventional processing methods. Hydrocyclone classification enables effective size separation and stabilization of particle size distribution, providing suitable feed for downstream processes. Microfluidic separation demonstrated selective concentrations of copper, increasing its content in the central fraction up to 0.52–0.58% with recovery up to 70–75% under optimal flow conditions. Bioleaching experiments using acidophilic microorganisms (Acidithiobacillus ferrooxidans and A. thiooxidans) revealed strong dependence on process parameters, achieving maximum recoveries of Cu (63%), Zn (58%), and Fe (43%) at pH 1.8–1.9 and 31–32 °C. The solid residues after bioleaching, composed mainly of aluminosilicates, were successfully utilized for geopolymer synthesis. The obtained geopolymer samples exhibited low water absorption (not exceeding 9.1%) and high compressive strength, meeting the requirements of Kazakhstan standard 26633-2015 (ISO 22965-1). The production of geopolymer materials from these residues contributes to the environmental rehabilitation of tailings storage facilities. The novelty of this work lies in the integration of microfluidic separation with bioleaching for fine tailing processing, enabling both selective metal recovery and subsequent conversion of residues into functional geopolymer materials. The proposed approach provides a sustainable pathway for simultaneous resource recovery and waste valorization, contributing to circular economy strategies in the metallurgical industry. Full article

Tailings are unconventional geomaterials that require dynamic characterisation due to seismic hazards at several storage facilities. Due to the anthropic origin of these materials, their dynamic properties differ from those reported for natural soils. In particular, the damping ratio is a relevant parameter that controls the dynamic response of tailings storage facilities. It can be estimated using different experimental methods. The objective of this research is to disclose the results obtained through laboratory tests in which the damping ratio was evaluated independently by Half-Power Bandwidth or the free-vibration decay methods. A comprehensive testing plan comprising resonant column tests and free-vibration decay tests was carried out on three types of tailings from the Riotinto mines (Huelva, Spain): Cerro Salomón Sand (CSS), High-Density Sludge (HDS), and Copper Lamas (CL). These tests were carried out under different effective consolidation pressures and torsional excitations. The results allowed the establishment of a series of relationships between the testing conditions and the identification of differences between the methods for tailings. Full article

Tailings management presents a critical challenge for the mining industry, particularly in mountainous regions with high seismicity and steep slopes. This article presents the development and design criteria for dry stacking of filtered tailings as a sustainable and safe alternative to conventional slurry tailings storage facilities (TSFs). The study focuses on the extreme conditions of a mountainous location characterized by complex topography with 10% slopes, space constraints, and significant seismic activity defined by a peak ground acceleration (PGA) of 0.3 g. The design methodology, which incorporates layered compaction of the filtered tailings to achieve a geotechnically stable structure, is detailed for a filtered TSF consisting of 7 terraces, each 10 m high, reaching a total height of 70 m. This approach minimizes the risk of liquefaction and prepares the filtered tailings surface for progressive closure, with unit operating costs (OPEX) of 2.5 USD/t. The results of the physical stability analysis confirm the viability of this solution: pseudo-static stability analysis yielded a safety factor of 1.22, demonstrating a significant reduction in water consumption and potential environmental impact. It is concluded that the dry disposal of filtered tailings is a technically robust option for tailings management in extreme mountainous environments, offering greater long-term safety guarantees and facilitating landscape integration, thus setting a precedent for mining projects in similar geographies. Full article

Securing mine sites is a challenging task due to the complexity of the infrastructure, the variety of physical and digital components, the distribution of assets and machineries, and the large number of stakeholders involved. Given the risks that are present in Tailings Storage Facilities (TSFs), mine operators are seeking technologies to accurately monitor the state of their dams. The latest developments implement evolutive monitoring and responsive risk management systems by adapting accurate Internet of Things technologies, automated mathematical model calculation to continually monitor the structural/geotechnical aspects of TSF, and a portfolio of innovative applications to support decision-making. Within this study, a comprehensive methodology is developed for assessing the environmental sustainability of a smart monitoring solution combining the life cycle assessment (LCA) method with the environmental risk assessment, which quantifies risk reduction potential. The use case scenario is identified based on real industrial data, also aligned with the common characteristics of tailing dams in Europe. Environmental sustainability of the smart monitoring solution is assessed through a cradle-to-grave LCA based on the ReCiPe 2016 (v1.1 Midpoint (H)) method. Monitoring impact alone is reduced primarily by the 40% reduction in monitoring visits, while the results show the environmental improvement of the TSF life cycle by 24% for CO₂-eq., as a step in-line with the EU’s long-term strategy for total decarbonisation in 2050, and Sustainable Development Goal 9 for Industry by the United Nations. Additionally, the 27% freshwater ecotoxicity reduction, 20% human toxicity (cancer) decrease, and the rest of the studied categories indicate an overall footprint improvement for the monitoring solution application on TSFs. The findings demonstrate clearly theoretical, practical and policy implications, not only for the benefit of such solutions for environmental protection, but also for the necessity of integrating risk in sustainability analysis approaches. Full article

This study addresses the ongoing challenge of mitigating the environmental risks posed by metal tailings storage facilities while simultaneously offering a novel and sustainable alternative to conventional construction materials. This study examined the utility of copper tailings and slag, two main byproducts of the mining industry, through the formulation of concrete that incorporates over 80% of these materials by weight. Comprehensive physical, chemical, and mineralogical analyses were performed following the Chilean and international standards. These assessments confirmed the presence of potentially hazardous elements and demonstrated the effectiveness of passivation treatments that make these materials suitable for reuse. Three experimental concrete mixtures were designed and tested under optimum laboratory conditions. The results showed that the compressive strengths exceeded 25 MPa within 7 days, whereas conventional concrete typically requires 28 days to achieve a comparable performance. The mixes also demonstrated effective immobilization of acidic and metallic components, ensuring compliance with the Chilean national regulations governing aggregates and construction materials. An economic evaluation highlighted the strong competitiveness of this approach. Production costs decreased by approximately 74% compared to traditional Portland cement concrete, primarily because of the lower raw material costs of tailings and slag. This research presents a technically feasible, economically viable, and environmentally beneficial solution that supports circular economy models in Chile, thereby providing a replicable framework for international applications. Full article

Uranium production tailing ponds in Kamyanske (Ukraine) are objects of increased radioecological danger. Violation of the stability and integrity of containment dams threatens the uncontrolled spread of radionuclides. The purpose of this study is to comprehensively assess the factors affecting the technical condition and environmental safety of the Sukhachivske tailing dam. The study included a visual inspection and detailed geophysical work using the natural pulse electromagnetic field of the Earth (NPEMFE) method. This method was chosen to identify hidden filtration paths and stress zones in the body of the earth dam. An analysis of the spatial distribution of waterlogging, filtration, and fissuring in the hydraulic structure was performed. Based on the results of the NPEMFE survey, six zones with varying degrees of waterlogging and stress–strain states of the structure were identified. The presence of externally unmanifested filtration paths and suffusion areas was established, and a tectonic scheme of fracture development in the dam body was compiled. A correlation was found between the dominant azimuths of crack extension (70–79° and 350–359°) and the directions of regional tectonic lineament zones, at the intersection of which the tailing pond is located. It has been established that modern tectonic movements along fault zones create zones of permeability, which serve as primary pathways for water filtration and further development of suffusion. This conclusion introduces a new tectonic feature for risk diagnosis and monitoring of similar hydraulic structures. Full article

Embankment structures in civil engineering, such as earth dams and fluvial dikes, have a crucial role in society. These structures, often used for water storage and mining tailing containment, are cost-effective due to their reliance on locally sourced materials. While the failure of concrete structures is not so frequent but often lead to severe consequences, embankment structures, particularly fluvial dikes, are more prone to breach and the consequences vary from mild to catastrophic, depending on the proximity to human populations. Worldwide, some fluvial dike failures have resulted in catastrophic outcomes for human lives, the local economy and the environment. This paper aims to develop a methodology to calculate in situ breach outflow hydrographs, resorting to real-time, non-intrusive and friendly access technology. The goal is to provide a practical platform for developing and testing integrated systems applicable to prototype failure cases. An accurate, real-time hydrograph estimation capacity improves risk assessment. The proposed methodology deploys, in a medium-scale experimental facility, common technology and data processing techniques to characterize the evolution of a fluvial dike failure. The morphodynamic and hydrodynamic components influencing the in situ breach outflow hydrograph are assessed by characterizing, in real-time, the breach morphology at the surface and underwater, the surface velocity maps and the corresponding cartesian coordinates. Full article

Despite technological advancements in mining, Chile lacks comprehensive risk management models for tailings storage facilities (TSFs), which hinders the prevention and mitigation of structural and environmental risks. This study aims to develop an integrated risk management model for TSFs in Chile, combining geological and mining engineering with an updated regulatory framework to enhance safety and reduce environmental impacts. The research adopts a mixed-methods approach. Qualitatively, it draws on 10 semi-structured interviews with engineers, geologists, academics, and professionals from the Chilean mining industry, selected through purposive sampling, to explore how and why the current risk management model should be improved. Quantitatively, it analyzes data from 303 surveys assessing the existing regulatory framework, a proposed new regulatory decree for Chile, and key variables to be considered in TSF risk management. The results present a new model that integrates geochemical and geotechnical characterization, process variables, in situ sensors, remote sensing, and artificial intelligence to generate dynamic risk indicators and early warning systems throughout the life cycle of the facility, including closure and liability valuation. Its multiscale design, adaptable to seismic and hydrogeological conditions and suitable for small- and medium-scale mining, overcomes existing static and fragmented approaches, enabling more effective decision-making with a focus on environmental and community safety. The study concludes that the model provides a robust and coherent tool for TSF risk management by integrating technical expertise, the current regulatory framework, and the management of key variables that enhance the ability to anticipate and mitigate structural and environmental risks. Full article