Mining, Volume 6, Issue 3 (September 2026) – 40 articles

The Al-Risha phosphate resource deposit in northeastern Jordan represents a promising phosphate ore requiring beneficiation to improve its suitability for industrial utilization. This study characterized the physical, chemical, mineralogical, petrographic, and microstructural properties of the phosphate deposit and evaluated physical, chemical, and thermal beneficiation approaches. Representative samples were characterized by particle-size analysis, X-ray fluorescence (XRF), X-ray diffraction (XRD), petrographic microscopy, and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS). Beneficiation experiments included dry and wet sieving, hydrochloric acid (HCl) and phosphoric acid (H₃PO₄) leaching, and calcination. The representative phosphate head sample contained 26.70 wt.% P₂O₅ and was dominated by francolite associated with calcite, quartz, and minor gypsum. Dry sieving provided limited upgrading, whereas wet sieving produced the highest P₂O₅ grade of 38.19 wt.% in the 0.250 mm fraction, with a mass yield of 41.54%, P₂O₅ recovery of 59.42%, and an upgrade ratio of 1.43. Among the chemical treatments, 5% (v/v) H₃PO₄ provided the most favorable balance between grade and phosphate recovery, producing 35.60 wt.% P₂O₅ in the 0.250 mm fraction with a mass yield of 80.62% and recovery of 97.72%, whereas increasing the acid concentration to 10% (v/v) adversely affected beneficiation performance. Calcination at 950 °C for 2 h increased the P₂O₅ grade to a maximum of 33.73 wt.%. Overall, the results revealed a trade-off between concentrate grade and phosphate recovery: wet sieving achieved the greatest physical enrichment and represents a promising reagent-free pre-concentration step, whereas dilute H₃PO₄ leaching provided the best balance between concentrate grade, mass yield, and phosphate recovery. These findings demonstrate the beneficiation potential of the Al-Risha phosphate deposit and provide a basis for further process optimization and techno-economic evaluation. Full article

The intensification of ground pressure and instability of surrounding rock in deep mining are the core safety challenges of metal mines. This article takes the first mining area of the Sishanling Iron Mine from 960 m to 1020 m as the object, and based on the data obtained from the multi-channel microseismic monitoring system for the whole year of 2025, combined with monthly mining and filling parameters, conducts a rock mass risk assessment that couples microseismic activity with the mining and filling process. The results show that microseismic activity and blasting operations exhibit a significant “resonance of the same frequency” response. The event-intensive areas are distributed along the fault zone and the edge of the goaf, and migrate in a directional manner from shallow to deep with the advancement of mining. By comparing the photos of the tunnel damage on site on a monthly basis, it was found that the incident gathering area was highly consistent with the locations of roof collapse and debris support, which verified the accuracy of microseismic positioning. Based on this, a risk discrimination index based on event frequency, energy release rate, and spatial concentration was established to dynamically evaluate the −960 m and −1020 m sections on a monthly basis. The local risk intensity in the −1020 m section was higher, and the risk increased compensatorily when the filling was delayed 2–4 weeks after mining, revealing the key control role of the mining filling coordination rhythm on the stability of the surrounding rock. The coupled evaluation system of mining filling microseismic risk constructed in this study can provide technical reference for active early warning and differentiated prevention and control of ground pressure in deep mines. Full article

Air-cooled tricone bits are widely used on rotary drilling rigs to achieve high production rates in open-pit mines. Their performance and service life are influenced by rock properties, machine characteristics, and operational parameters. Hole flushing accounts for approximately 50% of the energy consumed during drilling and affects penetration rates, bit life, and drilling costs. Although studies have focused on selecting suitable tricone bits, nozzle diameter selection has received limited attention and is commonly based on manufacturer recommendations or theoretical calculations involving assumptions. In this study, a practical method was developed to determine an appropriate nozzle diameter for tricone bits used in an open-pit lignite mine in the Soma Basin of Türkiye. This method includes theoretical calculations, together with field measurements and observations, to verify whether the drill rig and compressor operate properly and whether the drilling-performance parameters remain within acceptable limits. The field results indicated that appropriately selected smaller nozzle diameters can direct more compressed air toward the bearings, improving cooling and reducing bearing-related wear, and contributing to longer bit life without adversely affecting drilling performance. The results show that nozzle selection should consider compressor capacity, airflow distribution, bearing protection, and field performance in addition to theoretical calculations. Full article

Feldspar and quartz are essential ceramic raw materials, with feldspar acting as a flux and quartz as a structural filler. Feldspathic sand derived from granitic masses of the eastern Arabian Shield represents a promising local source. This study evaluates upgraded granitic detritus, commercially termed silspar, from the Khurs granite of the Dawadimi terrane. Twenty-five samples were chemically and technologically characterized; one compositionally anomalous sample (S2) was retained in the analytical tables for transparency but excluded before resource-level statistical preprocessing. Pearson correlation, principal component analysis and Ward hierarchical clustering were applied to 24 representative samples using eight chemical variables, while shrinkage, loss on ignition (LOI), whiteness (L*) and water absorption were used for external technological validation. Four chemistry-defined groups were identified: S1 and S3 form a dark impurity-rich pair; S4–S9 form the cleanest ceramic-grade group; S10–S13, S15–S17 and S24 define a transitional Ca-Fe-influenced group; and S14, S18–S23 and S25 form a more coherent potassic group. The firing variables differ significantly among the chemistry-defined groups under the standardized laboratory procedure. The results support controlled ceramic use of the representative Khurs-derived silspar, subject to stockpile homogenization and impurity control. Because phase proportions are normative estimates rather than direct XRD determinations, the work is presented as an integrated preliminary industrial-mineral screening assessment rather than a complete quantitative mineral-phase characterization. Full article

Rock-salt mines deform through chamber closure and vertical translation of the surrounding rock mass, yet these responses are commonly evaluated separately. This study integrates underground levelling, convergence monitoring, and mine geometry to identify the depth at which vertical motion changes from subsidence to uplift in the Kłodawa Salt Mine, Poland. The database comprises levelling campaigns conducted between 1962 and 2021 and 337 convergence series containing 7671 observations. Annual vertical velocities were calculated between actual survey epochs. The zero-vertical-velocity zone (ZVVZ) was estimated between adjacent measured levels with opposite median velocities; bootstrap resampling and mutual-nearest benchmark pairing quantified sampling uncertainty and local consistency. No transition was bracketed within the monitored 450–630 m interval in 1987–1992. In 1992–1994, shallow levels continued to subside while deeper levels uplifted, yielding crossing depths of 570.4 m in Field 1, 514.4 m in Field 2, and 476.8 m in Field 3. Field 1 retained the reversal in the 1994–2021 average, with a crossing near 585.3 m, although that long interval cannot resolve intermediate changes. Independent, mostly later convergence records show a marked increase in closure below 690 m and increasing horizontal dominance with depth. The ZVVZ is therefore a spatially variable kinematic boundary within a mining-modified deformation field, not a strain-free horizon: roof descent and floor uplift may generate rapid closure while mean vertical translation remains near zero. The method provides a reproducible monitoring state for deep salt mines. Future work should re-adjust the historical levelling networks, acquire synchronous levelling and convergence data at 690–780 m, and test excavation, geology, and backfilling controls using a calibrated three-dimensional viscoplastic model. Full article

Historical underground workings in the Maleia–Livezeni sector of the Petroșani Coal Basin were reconstructed from four archival mining plans and a coordinate-referenced Drawing Exchange Format (DXF) dataset. Twelve extraction-sector polygons, principal galleries, exploitation limits, dated mining stages, and 567 internally checked mining-elevation annotations associated with Coal Seam No. 3 were integrated in a geographic information system (GIS) using the Romanian Stereo 70 coordinate reference system (EPSG:3844). Net elevation differences between 2007 and 2026 at seventeen surface benchmarks were used as response variables. Nearest-feature relationships and mining-exposure indicators for 50, 100, and 150 m neighbourhoods were evaluated using exploratory Spearman rank correlations. Among the originally selected 50, 100, and 150 m neighbourhoods, cumulative gallery length within 50 m showed the strongest planimetric association with |Δ_Z| (ρ = 0.734, p = 0.0008, q = 0.010), while extraction-sector coverage and gallery length remained positively associated at broader scales. R19 showed the greatest immediate extraction-sector exposure, whereas R14, which recorded the largest elevation loss, was characterised by a broader concentration of surrounding workings. R09 recorded the smallest elevation change and was approximately 470 m from the nearest reconstructed extraction sector. Cumulative mining configuration was more informative than nearest-sector distance alone for interpreting spatially variable net surface-elevation change in this legacy mining setting and highlighted the limitations of archival GIS reconstruction. Full article

The transition from open pit to underground mining is becoming increasingly important as near-surface ore is depleted and mines seek to extend operating life. Yet its environmental and operational effects are often discussed separately. This systematic review examines the risks reported during the transition stage and develops an integrated framework for mine planning. Following a PRISMA-guided approach, peer-reviewed literature published between 2010 and 2026 was screened, and 69 records were included in the final review, comprising 66 primary studies and three directly relevant review articles. The evidence shows that the transition redistributes rather than simply reduces environmental pressure. Water management, ground stability, underground air quality, ventilation, and energy demand may become more important as underground development advances, while some surface impacts may decline as open pit activity decreases. The review therefore treats the active overlap period as a distinct planning stage and brings the main environmental and operational risks into one transition-planning framework. Full article

In the subsequent backfilling mining method, the composite structure formed by the ore pillar and the backfill is the key element in ensuring the stability of the working face. Its mechanical behaviour directly affects mining safety and ore recovery rates. In order to elucidate the mechanical response and failure mechanisms of rock-like backfill composite structures (RLBCS) under biaxial loading, specimens with different water-to-cement (W/C) ratios (0.5, 0.6, 0.7 and 0.8) for the rock-like backfill were prepared in this study. Biaxial loading tests were conducted, with digital image correlation (DIC) technology employed simultaneously to monitor the evolution of strain and displacement on the specimen surface. The results indicate that the biaxial strength of RLBCS decreases exponentially as the W/C increases. When the W/C exceeds 0.7, the strength reaches a plateau. The strength contribution of the backfill increases relatively. The axial stress–strain curve exhibits four distinct phases. A pronounced bimodal distribution is observed when the W/C exceeds 0.5. The evolution of lateral strain exhibits a transition point where compression is followed by expansion. The threshold for lateral expansion stress exhibits a non-monotonic variation. The modulus of elasticity decreases as the W/C increases. The apparent structural strain ratio exhibits a non-monotonic variation. The failure pattern exhibits marked asymmetry. The rock-like side shows tensile failure. Where the interface is present, this manifests as localised crushing at the top of the rock-like layer, cracking along the interface, and bulging of the backfill. The W/C ratio of the rock-like material governs the failure mechanism of RLBCS. The strain localisation modes in backfill materials are classified into two types: post-peak abrupt and pre-peak gradual. The evolution of interface strain exhibits four distinct stages: an initial abrupt change, cooperative deformation, crack initiation, and post-peak instability. The spatiotemporal evolution of interfacial delamination and the deformation of the backfill was quantified through displacement field analysis. The research findings provide a theoretical basis for the design of underground mining operations. Full article

The mining industry in Ghana, despite its economic significance, continues to grapple with occupational health and safety (OHS) issues, which include but are not limited to high accident rates and a largely reactive approach to safety. In this study, current practices in OHS management are assessed and a model is developed that reflects the interdependencies and associations between workplace hazards, accidents, health effects and preventative actions in a probabilistic fashion. A quantitative analytical design was employed and a sample of 298 workers, safety officers and supervisors from mines were surveyed. The data were analysed using Principal Component Analysis (PCA) to derive latent OHS factors, K-modes clustering and Hierarchical Clustering to classify worker safety profiles, and a Bayesian Network model was employed to investigate probabilistic dependencies. Three major OHS dimensions emerged from PCA: perceived adequacy of safety measures, formal training exposure, and safety resources. Three distinct worker profiles were identified, suggesting that the provision of physical safety equipment does not necessarily reflect perceived operational safety. Moreover, the Bayesian Network model indicated a conditional dependency between workers’ reported health issues and formal accident reporting, and that high hazard environments more than double the probability of an accident occurring (from 0.216 to 0.453). The results indicate that the industry is now operating in an incident-based manner. In order to mitigate the likelihood of accidents, management needs to move towards anticipatory safety management systems, which involve proactive health monitoring, equipment maintenance, and implementation of safety policies in practice. Full article

The mining industry is facing increasing pressure to improve operational safety, environmental performance, and resource efficiency while adapting to rapid technological change. In this context, the concept of Mining Industry 5.0 is emerging as an extension of Industry 4.0, promoting the integration of human-centric approaches with advanced digital technologies in mining systems. This paper proposes a 6S framework—Safety, Security, Sustainability, Sensitivity, Service, and Smartness—conceptualized as a Cyber-Physical-Social Systems (CPSS)-based model that co-optimizes these six dimensions and supports adaptive and human-centric mining operations across the entire value chain. The study is based on a structured literature review and a comparative analysis of digital transformation practices in related sectors, including manufacturing, logistics, and energy, to identify solutions applicable to mining environments. The key enabling technologies, including artificial intelligence, digital twins, cyber-physical systems, and intelligent automation, are evaluated as particularly relevant to mining operations for improving workplace safety, process efficiency, and environmental management. The paper addresses challenges, including high investment costs, limited digital competencies, data interoperability issues, and cybersecurity concerns in mining practice. The results support the development of a roadmap for Mining Industry 5.0 by integrating the proposed 6S framework with technical and organizational operations in the mining sector. Full article

Scientific evaluation of open-pit slope stability under the disturbance of underground goaf is critical to the safe production of open-pit coal mines. Taking an open-pit coal mine in Inner Mongolia as the engineering background, this study investigates the influence mechanism of underground goaf on slope stability. With discrete element numerical simulation, the movement law of overlying strata above the goaf is revealed, and the heights of the “three zones” and boundary movement angles are determined. Furthermore, limit-equilibrium theory is adopted to analyze slope stability affected by goafs from three perspectives: goaf span, occurrence position and inter-goaf spacing. The results indicate that under partial extraction conditions, goaf span is positively correlated with the height of the caving zone and negatively correlated with the boundary movement angle. As the goaf width increases, the mining-induced deformation field expands progressively, and a distinct bending-subsidence zone develops in the 50 m wide single-goaf case, resulting in a complete caving–fractured–bending-subsidence zonation. For adjacent goafs, smaller inter-goaf spacing promotes overlap of the mining-induced deformation fields and generally enhances overburden disturbance. As the spacing increases, the interaction between adjacent goafs tends to weaken, although the degree of reduction depends on goaf width and the deformation parameter considered. Therefore, the spacing of approximately 50 m observed in the present simulations is interpreted as a site-specific transition range rather than a universal critical threshold. Two landslide modes are identified in the Baozhixil open-pit mine: circular arc sliding and composite sliding controlled by the weak interlayer of No. 1 coal seam. Slope stability is negatively correlated with goaf span and positively correlated with the horizontal distance between the goaf and the slope face. For the analysis of inter-goaf spacing, slope stability shows a positive correlation with the proportion of non-collapse deformation area within the sliding mass. Full article

Mine drainage containing manganese (Mn) and zinc (Zn) poses a major environmental challenge. In Japan, Mn-rich mine drainage frequently exceeds the discharge standards of 10 mg/L for Mn and 2 mg/L for Zn. This study evaluated laboratory-scale continuous-flow constructed wetlands (CWs) for the treatment of both synthetic and actual mine drainage without addition of external organic carbon. The actual mine drainage was collected from an anonymous former Cu–Pb–Zn mine in Japan. Two limestone-filled CWs (2 L), one planted with Phragmites australis and the other unplanted, were operated at hydraulic retention times of 1–2 d. The influent mine drainage contained approximately 66 mg/L Mn and 10–15 mg/L Zn together with Fe, Cu, Cd, and Pb. During 170 days of continuous operation, the planted CW consistently achieved lower effluent Mn and Zn concentrations than the unplanted CW under both synthetic and actual mine drainage conditions. Effluent Mn concentrations in the planted CW ranged from 5.5 to 20.0 mg/L, compared with 46.1–54.2 mg/L in the unplanted CW. Likewise, effluent Zn concentrations ranged from 0.21 to 3.0 mg/L in the planted CW and from 2.4 to 10.1 mg/L in the unplanted CW. The superior performance of the planted CW was associated with enhanced limestone dissolution, elevated pH, and favorable rhizosphere conditions that likely promoted biologically mediated Mn(II) oxidation and the formation of Mn oxides, while Mn carbonate precipitation may also have contributed to Mn removal. These findings demonstrate that limestone-based planted CWs can effectively treat Mn-rich mine drainage without addition of external organic carbon and highlight their potential as sustainable, low-energy passive treatment systems for the long-term management of abandoned mine drainage. Full article

The selective separation of chalcopyrite from pyritic ores represents a major industrial challenge due to inadvertent copper activation. This study systematically investigates the batch flotation kinetics of a complex sulfide ore (Draa Sfar North, Morocco) using a first-order kinetic model ($R^2>0.916$). The impacts of pulp pH, chemical depressants, and specialized collectors were evaluated to optimize the copper/iron selectivity index ($S{I}_{Cu/Fe}$). The results reveal a high-alkalinity paradox: At pH 11.0, chalcopyrite kinetics experience a severe passivation bottleneck ($K_{i,Cu}=0.1330 {\min }^{-1}$). At pH 11.5, selectivity collapses ($SI=2.64$) due to persistent iron sulfide floatability ($K_{i,Fe}=0.2066 {\min }^{-1}$). Conversely, natural pH ($\approx 6.0$) provides a superior baseline ($SI=3.32$), where 40 g/t sodium cyanide (NaCN) yielded a peak index of $S{I}_{Cu/Fe}=10.25$. As an eco-friendly substitute, sodium lignosulfonate (LSNa) achieved outstanding performance ($S{I}_{Cu/Fe}=5.30$), reducing iron kinetics to their lowest level ($K_{i,Fe}=0.0356 {\min }^{-1}$) via ferric–anionic complexation. Furthermore, Danafloat 271 secured the highest collector-driven selectivity ($S{I}_{Cu/Fe}=5.03$) by suppressing the iron matrix ($K_{i,Fe}=0.0306 {\min }^{-1}$) following Hard–Soft Acid–Base principles. This study clarifies specific aspects of selective copper–iron flotation, demonstrating that natural pH circuits with green depressants or selective collectors offer a sustainable alternative. Full article

Blast-induced flyrock is one of the most critical hazards in surface mining and quarrying, posing significant risks to occupational safety, nearby structures, and the environment. Accurate prediction of flyrock distance is therefore essential for safe blast design and effective risk management. In this study, Random Forest (RF), Extra Trees (ET), and Support Vector Regression (SVR) models were developed to predict flyrock distance, and their hyperparameters were optimized using the Secretary Bird Optimization Algorithm (SBOA) and the Spider-Tailed Horned Viper Optimizer (STHVO). Prior to optimization, six cross-validation strategies were compared using GridSearchCV to identify the most appropriate strategy for each model. The final models were evaluated on an independent test dataset using the coefficient of determination (R²), root mean square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), variance accounted for (VAF), and Nash–Sutcliffe efficiency (NSE). Model interpretability was investigated using SHapley Additive exPlanations (SHAP). The results showed that appropriate cross-validation and metaheuristic hyperparameter optimization improved predictive performance, with the ET–STHVO model achieving the best overall results. SHAP analysis identified B/D, PF, H/B, RBS, and U/B as the most influential predictors. The proposed framework provides an accurate, robust, and interpretable decision-support tool for safer blasting operations. Full article

The Ouenza open-pit mine is one of Algeria’s major iron ore producers, where efficient blasting and fragmentation control are essential to maintaining stable, productive mining operations. The primary objective of this study is to quantitatively assess the agreement between predicted and measured rock fragmentation at the Ouenza open-pit mine. The research methodology includes a comprehensive analysis of blasting parameters. Field experiments used four blasts, all executed with the same blasting plans on the same working face to ensure comparability. The rock fragmentation was precisely measured and analyzed using the advanced image-processing software Wip-Frag to determine the particle-size distribution. The Kuz–Ram model predicted the fragment size distribution using the same blasting design implemented in the field, and the predicted fragmentation was quantitatively evaluated against Wip-Frag measurements using the coefficient of determination (R²), root mean square error (RMSE), and mean absolute error (MAE). The statistical evaluation yielded an R² of 0.9095, an RMSE of 9.71%, and an MAE of 6.54%, indicating good overall agreement between the predicted and measured fragmentation, despite noticeable deviations in the coarse-fragment size range. The observed discrepancies were mainly associated with potential inaccuracies in the field implementation of the designed blast pattern, limited compliance with blasting procedures, and the natural heterogeneity of the rock mass. The results show that comparing Wip-Frag measurements with Kuz–Ram predictions is an effective way to identify discrepancies between predicted and actual fragmentation and to determine the field factors driving these differences. These findings provide practical insights into blast implementation and fragmentation control under actual mining conditions. Full article

Current geological site assessment models focus on examining stable natural features and neglect measuring surrounding industrial and environmental hazards. This methodological deficiency is clearly evident in the management of technological heritage in existing or abandoned mining areas. This research presents the modified GAM_GES geo-environmental assessment model to address this practical gap in the regional planning of industrial geoparks. The proposed model integrates the geo-environmental safety (GES) block as a mathematical discount factor that measures the risks of surface deformation, seismic activity, gas emissions, and pollution from mining waste. The research applies the developed criteria to the Kirov Mine database in the Kuzbass Basin, renowned for its combined technological and geodynamic characteristics. The numerical results demonstrate a lower overall site value compared to the conventional model due to the detection of active ground fissures and continuous methane migration across tectonic faults. The model provides planners with a quantitative decision support framework for dividing industrial heritage sites into multiple safety zones that ensure visitor protection and the security of sustainable tourism facilities. Full article

Cemented paste backfill (CPB) is widely used in mining, but its high brittleness, low toughness, and limited ductility can cause it to crack and spall, or even damage the overall structure, thereby limiting its application in deep underground mine excavations. To this end, this study investigates the damage and failure mechanisms of cemented gangue–rubber paste backfill (CGRPB) and analyses its energy evolution characteristics. The aims are to: (i) assess the CGRPB mechanical properties, i.e., toughness, ductility, and brittleness due to incorporating rubber; (ii) analyze the fracture propagation process of CGRPB from an energy evolution perspective. Therefore, monotonic and cyclic compression tests were conducted on CGRPB samples containing 0%, 5%, and 10% recycled rubber powder. This study focuses on analyzing compressive strength, failure modes, stress–strain responses, energy evolution and the damage evolution process. Key findings include: (1)the effect of rubber incorporation on strength is dosage- and curing-age-dependent; a moderate rubber content (5%) improves early-age strength, whereas excessive rubber addition reduces strength due to increased porosity and weakened load-bearing capacity; (2) samples with rubber significantly reduce the length, number, and width of cracks, achieving better structural integrity; (3) introducing rubber improves the pre-peak deformation capacity of the samples; (4) the strain growth magnitude is positively correlated with the rubber content, enhancing their toughness and ductility; (5) adding rubber effectively reduces the damage propagation rate within the sample; (6) under loading, rubber elastic deformation in samples dissipates energy, which describes the approximately linear energy storage and dissipation trend; (7) among the investigated rubber contents, 5% rubber incorporation achieved a favorable balance between mechanical strength, toughness, and ductility. Full article

Deep metal mines commonly contain vertically stacked goafs whose geometry and rock mass properties are incompletely documented. This study evaluates a field-constrained screening framework for high-displacement material scenarios at the Lehong Pb-Zn mine. The framework combines a Latin hypercube sampling (LHS)-FLAC3D response library with static Bayesian inference. Evidence comprised 93 goaf records, 186 Mathews exposed-surface assessments, laboratory constraints, and 40 archived numerical scenarios, whose maximum downward displacement ranged from 4.48 to 31.75 cm. Friction angle φ showed the strongest marginal Pearson correlation with displacement (r = −0.81), followed by cohesion (r = −0.55) and elastic modulus (r = −0.22). At the response library Q75 threshold of 15.04 cm, the Laplace-smoothed probability increased from 0.262 (95% credible interval, 0.142–0.403) across all scenarios to 0.600 (0.352–0.824) under joint cohesion–friction angle degradation. However, the archived design was not an ideal 40-point LHS, and bootstrap resampling retained the scenario ordering in only 45.8–54.8% of replicates. All 93 inventory identifiers matched the Mathews stability table, enabling reproducible site-level triage when Bayesian network results are combined with treatment and stability evidence. The framework is an exploratory screening tool rather than an absolute failure probability model, collapse propagation model, or dynamic early warning system. Full article

Lithium, as a Li-ion battery constituent, is pivotal for the transition to clean energy. Western Australia (WA) has become a global leader in hard-rock lithium mining, realising 10-fold growth from 2010 to 2024 and with royalty receipts to the WA government surpassing $1 billion AUD. Given the sector’s economic significance, we analyse key performance metrics including resource/reserve build, production growth, cumulative capital deployed, capital intensity, and development timelines for the new-generation lithium mines. Several enabling factors supported the rapid build-out of capacity. These include an efficient mine permitting process to manage environmental impacts and competing land use issues, a stable royalty regime, energy and logistics infrastructure, availability of a skilled workforce, and mining services capability. Contrary to the standard industry narrative that new mineral projects are constrained by legislative delay, the new lithium projects achieved development timelines of 7 years or less from first resource to production. This has broader implications for critical mineral projects where success is likely to depend less on strategic classification and more on project quality, financing, and regional capability. Full article

Numerical modelling is a powerful tool used in geomechanics; however, its reliability depends on proper validation. This study demonstrates the use of intelligent rock bolt measurements to validate the numerical model of underground deformation, providing a practical and applicable approach even with all numerical modelling simplifications. A numerical model of a selected Case Study Location was developed using geomechanical data from laboratory tests (uniaxial compressive strength, triaxial test, and Brazilian test). The numerical model was validated using deformation data collected by intelligent rock bolts installed in the underground mine. Applying statistical data correction methods, the model data accuracy was further improved. Applying Kalman filtering improved the correlation between measured and modelled deformations from 0.90 to 0.98, demonstrating the effectiveness of statistical methods. The novelty of this work lies in the combined use of intelligent rock bolts, FEM simulations, and statistical data correction to achieve a practical and reproducible validation framework, even when simplified geological assumptions are used. Full article

This study investigates the influence of unsteady heat and mass transfer processes on the formation of gas composition and thermal conditions in a large cross-section (132 m²) blind-end chamber of a gypsum mine during the operation of diesel-powered mining equipment, including a front-end loader representing the LHD class and a dump truck. The modeled system considers a chamber where the LHD operates continuously, while the dump truck enters periodically to perform haulage cycles. Ventilation is provided from an adjacent panel haulage drift using a booster fan. Numerical simulations were carried out using ANSYS Fluent within the RANS framework, employing the realizable k-ε turbulence model, with consideration of thermal and gas convection. A dynamic mesh approach was applied to explicitly represent the motion of the dump truck. Both steady-state scenarios, corresponding to extreme equipment positions, and a fully transient case involving dump truck entry into the chamber followed by idling were analyzed. The results demonstrate that the movement of the dump truck generates a pronounced piston effect, which alters the jet flow structure and temporarily increases the supply of fresh air to the working face. It is shown that steady-state assumptions based on prolonged equipment presence near the face overestimate the total NO_x concentration within the large chamber and may not adequately reflect actual gas conditions over typical loading cycle durations. The analysis of unsteady processes using the dynamic mesh approach reveals significant inertia in contaminant accumulation within the chamber. This finding enables a more accurate estimation of the required airflow rate, reducing excessive safety margins compared to calculations based on the assumption of continuous equipment operation near the face. Full article

Stockpiles and run-of-mine (ROM) pads are critical control points between mine production and processing plant feed. The grade, quality mix, and variability of material delivered to the crusher and mill are largely determined by how these structures are designed, built, and reclaimed. Despite the operational significance of stockpile management, the field remains fragmented across five distinct research streams—physical blending theory, stockpile state modelling, reclaim sequencing and equipment scheduling, plant-feed and stockpile blending optimization, and sensor-driven reconciliation and closed-loop control—with limited integration between them. This paper presents a systematic review of 27 sources published between 1976 and 2025, including peer-reviewed journal articles, conference papers, a preprint, a book, and one industry publication. The literature search was conducted in May 2025 using Scopus, Web of Science, and Google Scholar, with records screened by title/abstract and full text for direct relevance to stockpile reclamation or grade blending in mining operations. A structured coverage matrix identifies that studies combining high spatial fidelity with strong optimization rigor are consistently absent from the literature, and that uncertainty handling and sensor-driven or real-time capability remain substantially underdeveloped. Six research gaps are identified and prioritized by practical significance, implementation readiness, and literature maturity. The four most operationally critical gaps concern: spatially explicit reclaim scheduling under live ROM-pad constraints; tractable multi-attribute blending formulations for polymetallic operations; uncertainty propagation to plant-feed predictions; and field-scale closed-loop validation. The review provides a structured development roadmap for ROM-pad optimization frameworks and identifies the specific integration challenges that must be addressed to move the field from static stockpile monitoring toward adaptive, sensor-updated decision support. Full article

The mining industry continues to face significant safety challenges, particularly with powered haulage equipment (PHE). PHE incidents account for a substantial percentage of mining-related fatalities, often resulting from vehicle collisions, equipment rollovers, operator errors, and blind-spot hazards. Despite the industry’s efforts to improve safety protocols, fatal accidents involving haulage trucks remain persistent. The mining industry has increasingly adopted automation to enhance operational efficiency and improve safety, particularly in surface mines where haulage truck accidents remain a critical concern. Automation has significantly reduced human exposure to hazardous tasks by removing operators from dangerous environments, thereby mitigating risks associated with human error and fatigue-related accidents. However, achieving zero fatalities in mining operations remains an ongoing challenge, necessitating a deeper evaluation of current technologies and safety interventions. This paper explores the review and integration of advanced safety technologies, such as real-time monitoring, machine learning-based predictive models, and enhanced automation frameworks to improve hazard detection and response time. A structured methodology is employed to review automated systems, accident data analysis, and an assessment of automation technologies in active mining operations. Specific findings highlight the impact of automation on reducing accident rates, the effectiveness of various intervention strategies, and challenges in full-scale implementation. The novelty of this paper lies in its roadmap to achieving zero fatalities through a review of structured integration of automation and predictive safety interventions. It outlines the broader benefits of Automated Haulage Systems, including productivity gains and operational cost reductions, contributing to the ongoing discourse on mining safety by providing a data-driven framework for the successful implementation of automated haulage trucks, ensuring a safer and more efficient mining environment. Full article

Lined rock caverns offer a promising option for underground hydrogen, helping to mitigate renewable intermittency and enhance system stability. Considering the geological characteristics of hard rock formations in Southern Ontario, Canada, this study establishes a thermo–gas–mechanical coupled framework that incorporates hydrogen mass and energy evolution in the cavern, gas–wall convective heat exchange, dynamic cavern-volume feedback, and the deformation behaviour of the sealing layer, concrete lining, and surrounding rock. The influences of cavern geometry, sealing material, and in situ stress on the short–term thermodynamic and mechanical responses are further examined. The results show that hydrogen temperature and pressure exhibit clear stage–dependent evolution during the charging–storage–discharging cycle. The comparison between the first and 20th operating cycles indicates that repeated operation mainly causes a moderate adjustment of the cyclic thermal state and temperature–pressure baseline, without changing the overall stage–dependent response pattern. During charging, temperature and pressure increase simultaneously; during storage, both gradually decrease as thermal energy is transferred to the cavern wall; and during discharging, expansion causes pronounced cooling and depressurization, followed by gradual recovery driven by heat transfer from the surrounding rock. Cavern geometry significantly affects stress redistribution around the cavern. The circular cavern shows a relatively uniform stress distribution, whereas the arched cavern is more prone to local stress concentration near the sidewall–floor transition zone. The sealing material mainly influences gas temperature fluctuations through its thermal conductivity. The fibre–reinforced plastic (FRP) sealing layer amplifies thermal fluctuations during cyclic operation, whereas the steel sealing layer promotes heat dissipation through the lining and surrounding rock, thereby moderating cavern–gas temperature variations. In situ stress difference further controls the directional distribution of stresses around the cavern. As the minimum horizontal principal stress increases, compressive stress concentration at the crown and invert becomes stronger, while relative stress release occurs near the sidewalls. These findings provide a thermo–mechanical basis for preliminary cavern–geometry design, comparison of sealing–layer thermal performance, and assessment of in situ stress adaptability for lined rock cavern hydrogen storage in Southern Ontario. Full article

To examine the deformation behavior and failure mechanisms of large-scale mine chutes under complex service conditions, we performed multiple C-ALS three-dimensional laser scanning surveys on the 1#, 2# and 3# chutes at an iron mine in Anhui Province. The results showed that all three chutes had severe non-uniform expansion, with maximum diameters of 12.2 m, 14.8 m and 16.9 m, respectively. The maximum annual wear rates during the detection period were 2.4 m, 6.0 m and 2.5 m, respectively. The failure of the chutes was mainly caused by local block collapse drops, influenced by the joints and fissures of the surrounding rock, and the wear showed significant discontinuous and non-uniform characteristics. Based on the detection data, a three-peak Gaussian model is established to describe the nonlinear distribution of the expansion along depth, with peak centers located at −462 m, −497 m and −520 m. By comparing linear and exponential models, it is determined that the expansion exhibits a linear evolution trend with time. Based on the maximum diameter and annual wear rate, we estimate the remaining safe service life of each chute, and provide the confidence interval for the expansion value at a 90% confidence level (such as [1.31 m, 4.83 m] at −520 m). Research shows that high-precision 3D laser scanning can effectively reveal the deformation and evolution laws inside the chute. It is recommended to immediately take reinforcement measures for chute 2 and establish a dynamic monitoring system for the common weak zone between −480 m and −520 m. Research on the evolution of surrounding rock fractures should be carried out to provide a scientific basis for chute life assessment and risk control. Full article

In the Western Anti-Atlas, the stratiform copper mineralisations of the Tabia Member are distinctly hosted within sedimentary rocks, forming deposits comparable to the sediment-hosted stratabound copper (SSC) type. In Tizert, Ouarmdaz, and Talat n’Ouamane, the sandstones and clays host primary sulphides as disseminations and copper carbonates occurring as small continuous or lenticular beds, small geodes, and coatings on clay laminations. In Tiferki, the conglomerates are more mineralised; sulphides are represented by chalcopyrite and bornite, locally altered into chalcocite. Copper carbonates appear as malachite and azurite coating pebbles and deeply impregnate the granular matrix. From a sedimentological and sequence-stratigraphic perspective, the conglomeratic level at Tiferki represents a low-sea-level prism (LST) formed during a stage of maximum platform exposure allowing erosion products to accumulate at the base of the slope. By contrast, the silty–sandy complex known as the “Talat n’ Ouamane level” corresponds to a prograding sedimentary sequence (Highstand Systems Tract, HST) that developed after a relative regression where the platform was only partially exposed. In both cases, relative sea-level fall promoted the emergence of the hinterland and active erosion, supplying the depositional environment with coarse detrital during the maximum drops in sea level and sandy-to-micro-conglomeratic deposits during less pronounced regressions. This detrital supply probably brought copper in the form of grains and especially dissolved copper, which is largely deposited at the bottom of slopes and in marine environments where microbial communities contribute to the precipitation of copper. The selective distribution of sulphides within the Tabia Member shows that only the low-sea-level and high-sea-level prisms are enriched in stratiform copper, while the transgressive and maximum flooding systems tracts lack significant mineralisation. This suggests that sea-level variations played a controlling role in copper deposition. The regressive trend of the high sea-level suite continued until emergence, reflected by the invasion of the environment by red or ochre siltstones from the alluvial plain. The emergence at the transition from sandstones to dolomites, and the “Red Beds”-type mineralisation embedded in these subaerial facies, support the syngenetic origin of the sulphides in the Tabia Member. After this main emplacement of stratiform copper, the sulphides would have undergone remobilisation and alteration during a significant episode of vertical water escape that deformed the host facies and enhanced mineral concentration within permeable sandstones. Even the clays were delaminated and coated with a thin films of copper carbonates on their surfaces. In the Tamjout dolomites, carbonates are percolated by acidic solutions, contributing to the brecciation and silicification of the stromatolitic layers. Copper mineralisation accompanies this silicification and fills the karstification pockets. Full article

Mining-induced subsidence represents one of the most significant long-term geomechanical hazards associated with underground coal exploitation, often continuing for decades after mining activities have ceased. Understanding the persistence and spatial distribution of post-mining ground deformation is essential for evaluating residual geological hazards and improving long-term monitoring strategies in former mining regions. This study investigates the long-term evolution of mining-induced subsidence in the Maleia sector of the Jiu Valley Coal Basin (Romania), an area historically affected by intensive underground coal extraction. A geodetic monitoring network consisting of seventeen permanent benchmarks, initially established in 2006, was reoccupied and remeasured using Global Navigation Satellite System (GNSS) technology in 2026. The comparative analysis was performed against historical measurements acquired during the 2007 monitoring campaign, providing a nineteen-year temporal framework for deformation assessment. Analysis of vertical displacements revealed persistent subsidence at all monitored benchmarks, confirming the continued post-mining adjustment of the geological structure. Measured cumulative vertical displacements ranged from −0.082 m to −3.853 m, with the highest deformation recorded at benchmark R14. The calculated average annual subsidence rates reached values of up to −0.203 m/year and are reported as normalized indicators of cumulative deformation over the nineteen-year observation interval. The results demonstrate that mining-induced geomechanical instability may persist for decades after underground mining has ceased, emphasizing the necessity of long-term monitoring strategies in former coal mining regions affected by residual geological hazards. This study provides one of the few long-term GNSS field datasets documenting delayed mining-induced subsidence over a nineteen-year observation period in an underground coal basin, contributing rare field evidence of persistent post-mining geomechanical evolution in Eastern Europe. Full article

Blast-induced ground vibration is a critical environmental hazard in open-pit mining operations, capable of causing severe damage to adjacent structures and infrastructure. Accurately predicting vibration intensity is universally quantified by the peak particle velocity (PPV) index. Among the various factors affecting blast-induced ground vibrations, the distance from the blast face to the monitoring point (D) and the charge weight per delay (W) are the most influential and controllable parameters in a specific mine site. Therefore, these variables were selected as inputs for PPV estimation. The present study develops advanced white-box machine learning (ML) models, including Multi-Expression Programming (MEP), Gene Expression Programming (GEP), Multivariate Adaptive Regression Splines (MARS), and Stronger Variable Creator Machines (SVCMs), for predicting PPV. The general explicit equation was derived from the developed ML models implemented in a spreadsheet program, which can be easily used to estimate PPV. The MEP model achieves the highest accuracy, with a correlation coefficient (CC) of 0.993177 and a root mean square error (RMSE) of 0.836337, followed by the MARS, GEP, and SVCM models. The results of the present study, supported by k-fold cross-validation and parametric analysis, confirmed the potential of the proposed models for PPV estimation. Full article

Conventional pavement design methods are generally intended for highways and are not suited to the extreme loading conditions experienced by mining haul roads. This study presents an innovative pavement design for a heavily trafficked phosphate mine haul road (≈22.35 kT·day⁻¹) constructed entirely from phosphate mine waste rock (PMWR), offering a sustainable alternative to conventional aggregates. The proposed structure comprises a 0.35 m sub-base (0–100 mm), a 0.25 m base (0–63 mm), and a 0.07 m semi-granular asphalt concrete (BBSG 0–20 mm) wearing course designed to combine high mechanical performance with effective dust control. The design was validated through an integrated experimental program that included repeated load triaxial testing (RLTT), asphalt stiffness, fatigue and rutting tests, thermogravimetric analysis (TGA), and full-scale field trials involving EV₂ plate-load testing, dust monitoring, and emergency braking tests using a Komatsu 730E haul truck. The results demonstrate that the proposed pavement provides excellent structural performance. The asphalt mixture achieved a stiffness modulus of 9160 MPa, a fatigue resistance of 139.6 µε, and a proportional rut depth (PRD) of only 2.2%. In the field, the compacted sub-base and base reached average EV₂ values of 153 MPa and 181 MPa, respectively, confirming their high load-bearing capacity. The paved haul road reduced airborne dust emissions by approximately 91%, surpassing the mine’s target of 80%, while also enabling haul-truck operating speeds to double, with associated reductions in tire wear and maintenance. Despite these performance gains, the proposed solution remains economically attractive, with a construction cost of approximately 23.97 €/m². Overall, the study demonstrates that phosphate mine waste rock can be successfully transformed into a durable, cost-effective, and environmentally sustainable pavement solution for heavy-haul mining roads, providing a practical example of circular economy principles in mining infrastructure. Full article