Mine Waste Management Research Articles

Recovery of mining and agri-food wastes in fired materials: a case study of the Moroccan industry.

The linear economy follows the "take-make-dispose" model and generates huge amounts of waste without consideration for recycling or reuse. This model which deals with raw materials puts pressure on natural resources and creates a serious environmental impact. In a circular economy, the "reduce-reuse-recycle" model is applied to recycle waste into resources and reduce the impact on the environment and society. This work aims to highlight the significance of implementing a circular economy approach in the construction sector by merging two different production lines, notably mining activity and agri-food industry. The investigation presents sustainable management of coal mine waste (CMW) and olive pomace (OP) in the production of eco-friendly fired materials and introduces an innovative approach for manufacturing lightweight fired bricks. Microstructural, physical, mechanical, and thermal properties were determined to evaluate the technological quality of fired materials at 900°C. As a pore-forming agent, adding 10 wt% OP yielded specimens with a bulk density of 1552kg/m3, water absorption of 19.80%, apparent porosity of 29.61%, loss on ignition of 26.98%, and compressive strength of 7.08MPa, satisfying standards for clay masonry units. Simultaneously, it enhances the thermal insulation by reducing thermal conductivity by 18% compared to the control sample with CMW. In this regard, the transition to a greener construction sector necessitates the immediate implementation of a circular economy approach to developing eco-friendly building materials by recovering large amounts of industrial waste, limiting the overuse of natural resources (e.g., clays), and improving the engineering properties of the final product.

MINERAL PRODUCTION AND ENVIRONMENTAL POLLUTION IN NIGERIA

This study empirically determined the effect of mineral production on environmental pollution in Nigeria from 1985 to 2022. The research utilised time series data obtained from the Central Bank of Nigeria (CBN) data bulletin and the World Development Indicators (WDI) of the World Bank. The data analysis methodologies utilised include descriptive statistical analysis, ADF Unit Root test, ARDL Bound Co-integration test, and ARDL methodology. The result of the ADF unit root test indicated the presence of a combination of stationary and non-stationary elements. That is a mixture of I(0) and I(1). Furthermore, the ARDL limits co-integration test has shown the presence of a long-term link between the variables. Finally, the ARDL estimation revealed that crude petroleum and natural gas production, likewise mining and quarrying had significant and positive implication on emission of CO2 in both long and short runs. Coal production had positively significant impact on CO2 emission in the long run but positively insignificant impact in the short run. In addition, metal ores positively and insignificantly impacted on CO2 emission in both the long and short runs. The study's results indicated that mineral mining in Nigeria resulted in a rise in environmental contamination. The report proposed that the Nigerian government should thoroughly evaluate and revise current environmental laws and regulations in order to effectively address the environmental consequences of mineral development. This should include establishing clear standards, guidelines, and permits for mining operations, waste management, pollution control, and rehabilitation of mining sites. KEYWORDS: Mineral Production, Environmental Pollution, CO2 Emission

Valorisation of Aggregate-Washing Sludges in Innovative Applications in Construction.

The valorisation of sludges from aggregate production into construction materials is required for full circularity in mining waste management. This study explores valorisation pathways, relevant regulatory frameworks, and End-of-Waste (EoW) criteria for specific settings in Spain and Norway. The explored valorisation routes involved the production of filler, supplementary cementitious materials (SCMs), and lightweight aggregates (LWAs) for the production of cement-based products, and precursors for 3D printed construction material. The sludge from Norway revealed a non-polluted stream and a stream contaminated with organic phases and clays. Sludge-based filler proved suitable in concrete production with contents of up to 40% of total binder, providing adequate consistency and cohesion. However, clays in the sludge increased the demand for water and superplasticizer. Clay contents were still insufficient for the applications as SCMs, as the calcined sludge demonstrated limited reactivity. The application to produce LWAs was promising, but further microstructure optimization is still required. The clay content was also relevant for the sludge from the site in Spain, as it provided 3D printing mixes with good plasticity. The dosage optimization still required the addition of enzymes, limestone, and natural fibres to improve cohesion, workability, and resistance to the cracking of the 3D printing mix.

Circular economy strategies in sedimentary phosphate mine reclamation: Development of technosol from phosphate waste rock

Proper management of mine waste plays a crucial role in minimizing environmental impacts. One potential solution to tackle this problem involves transforming mine waste rock into soil to facilitate the process of mine restoration. The aim of this study was to assess the mineralogical, chemical, and physical characteristics of technosol derived from phosphate mine waste dumps. Following this evaluation, a novel rehabilitation strategy was proposed. For this purpose, a total of 32 samples were systematically collected across a 4 ha area of technosols, which had been established in accordance with the waste rock soil rehabilitation strategy involving geomorphic reshaping. According to the findings, phosphate mining left the soil with a sandy texture, resulting in a degraded soil structure with severely unfavorable crop growth conditions, notably poor stability, and low water retention. The chemistry of the studied soils was characterized by the dominance of CaO (29.02 wt%± 1.01) > SiO2 (27.61 wt% ± 0.61) > P2O5 (11.34 wt% ± 0.23) > MgO (5.97 wt%±0.16). Mineralogically, the samples were mainly formed by quartz, dolomite, calcite, apatite, and clay minerals. The prevalence of dolomite played a significant role in enhancing the accessibility of Mg as an essential nutrient and the occurrence of apatite in the soil resulted in the presence of P2O5. However, the abundance of Ca was linked to three major minerals: calcite, apatite, and dolomite. X-ray fluorescence analyses demonstrated that the concentrations of Fe2O3, K2O, and SO3 did not exceed 2 wt%.Organic matter, represented by SOC <0.2% and N < 0.02%, demonstrated an extraordinary deficiency in the study area. The analysis of element bioavailability confirmed that the soil was rich in Ca (10383,26 mg/kg), Mg (278,47 mg/kg), Zn (12,82 mg/kg), and Cu (3,7 mg/kg) but deficient in other essential nutrients such as P, K, S, Mn, and Fe. Our research results provide a set of recommendations aimed at enhancing existing mine rehabilitation practices applicable to both pre- and post-rehabilitation phases, leveraging automated mineralogy and circular economy principles. Notably, we propose a rehabilitation strategy to be implemented prior to the geomorphic reshaping phase, which is intended to reduce costs and efforts associated with soil reconstitution.

Development of an affordable light emitting diode spectrophotometer paired with a Python program for calibration and linearity testing and the measurement of uranium(VI).

Uranium (U) is a radiologically and chemically toxic element that occurs naturally in water, soil, and rock at generally low levels. However, anthropogenic uranium can also leach into groundwater sources due to mining, ore refining, and improper nuclear waste management. Over the last few decades, various methods for measuring uranium have emerged; however, most of these techniques require skilled scientists to run samples on expensive instrumentation for detection or require the pretreatment of samples in complex procedures. In this work, a Schiff base ligand (P1) is used to develop a simple spectrophotometric method for measuring the concentration of uranium (VI) with an accurate and affordable light-emitting diode (LED) spectrophotometer. A test for a higher-order polynomial relationship was used to objectively determine the calibration data's linearity. This test was done with a Python program on a Raspberry Pi computer that captured the spectrophotometer's calibration and sample measurement data.

Characterization, potential valuable metals recovery and remediation of historic wolframite mining waste

The understanding of tungsten (W) mineral weathering and mobilization in nature remains limited due to W being a transition element with a wide range of oxidation states, which enables it to form a variety of complex chemical compounds. This study examined W mining waste at the abandoned Wolfram Camp mine in North Queensland, Australia, to address this gap. The mineralogical analysis showed the W tailings primarily consisted of silicates, including quartz, illite/mica, plagioclase, and K-Feldspar, with low WO3 content. Static acid mine drainage (AMD) tests indicated most tailings were non-acid forming, while groundwater samples exhibited acidification, with pH ranging from 3.8 to 5.2. The reprocessing trials using gravity separation and bioleaching demonstrated promising results, suggesting both techniques could effectively recover resource and decontaminate the mining waste. The gravity separation reprocessing test has successfully recovered 48.4% W from the tailings, with the resulting W concentrate achieving a 21.6% WO3 grade. On the other hand, the bioleaching reprocessing exhibited a remarkable 44-fold enrichment of W from the tailings, with 2.2% W in the AMD sediment. Synchrotron-based XFM/μ-XANES imaging analysis revealed significant wolframite weathering in reprocessed W concentrates. This study proposed a comprehensive approach, integrating environmental remediation and resource recovery technologies, to repurpose abandoned W mining waste. Passive treatment appears to be an economical option for remediating abandoned W mine sites. The findings provide valuable insights for sustainable W mining waste management and the rehabilitation of the abandoned Wolfram Camp W mine site.

Microbiodiversity Landscape Present in the Mine-Tailings of the “Sierra de Huautla” Biosphere Reserve, Mexico

Large-scale mining activities generate significant amounts of waste that accumulates in the environment. These wastes, known as mine tailings, contain high levels of heavy metals, posing risks to human health and causing severe damage to ecosystems. In this study, we determined the heavy metal content of mine tailings in the Sierra de Huautla Biosphere Reserve (REBIOSH), Mexico, and investigated their effect on microbial composition. One of the sites historically contaminated with metals was sampled in three different locations, labeled S1, S2, and S3. A fourth site free of heavy metals (S4) was also used as a control. Our results showed high levels of As, Pb, Cd, and Ag, potentially dangerous metals that exceed thresholds set by international regulatory agencies. Metal contamination indices indicated moderate to extreme enrichment for As, Cd, and Pb, posing potential ecological risks. A metagenomic study of mine tailings showed a core specie-specific microbiome covered by Sinimarinibacterium flocculans, Jiangella anatolica, Thiobacillus denitrificans, Fontimonas thermophile, Sphingomonas koreensis. These may be associated with the processing of heavy metals. A comparative study using the ALDEx2 revealed that less represented species like Variovorax paradoxus, Usitatibacter rugosus, Usitatibacter palustris, Sphingosinicella microcystinivorans, Sphingobium yanoikuyae, and Stella humosa may serve as microbial markers in metal-contaminated environments. In addition, we detected rare or low-abundance species belonging to the phylum Armatimonadota, Candidatus Melainobacteriota, Candidatus Saccharimonadota, Chlamydiota, Deinococcota, Elusimicrobiota, Bacillota, Rhodothermota and Verrucomicrobiota, which could play an important role in ecosystems contaminated with heavy metals. Also, we found site-specific taxonomic representatives such as Nitrososphaera gargensis and Nitrospira nitrificans dominating the S3 ecosystem; Ensifer aridi (S2 and S1), N. nitrificans (S2), while Reyranella soli dominate the S1 soil. These organisms could be crucial for nitrogen access in oligotrophic environments and underscore the adaptability of microbial life to extreme conditions. This is the first comprehensive study of the microbial composition in this important ecological site of the Mexican geography and can provide future guidance for the management and biological treatment of mining wastes.

О проблемах системы управления горнопромышленными отходами в Арктической зоне Российской Федерации

Mining waste products cause serious damage to the human health and unique ecosystems of the Russian Arctic. The article examines the current state of the mining waste management system and the possibilities how to increase the investment potential of mining waste recycling. The issue of involving mining waste products into the economic circulation is a complex task and its solution requires improving the state mining waste management system, including correcting the existing and adopting the new laws, implementing various target programmes, using tax preferences as well as economic stimulation measures.

Potential recycling of mine tailings for PMC’s Padcal Mine, Philippines

Industrialized countries attempted to obtain minerals, resulting in a developed method to extract valuable minerals from the ground. Consequently, waste mine tailings are produced and, when left to pile up, will potentially be hazardous to the environment and the people. However, more mine tailings become a problem when the organization needs clarification on the minerals' value and what they can be used for. This study focuses on a multi-criteria analysis of the potential repurposing of the Philex Mining Corporation (PMC) tailings in Benguet, Philippines. While mining policies were considered, findings show that piles of mine tailings had not been considered for refining to produce more resources for development, construction, and economic growth The study employs qualitative inquiry to understand better the grassroots processes and reconnaissance of the stored tailings. The analysis tries to promote sustainable practices – presenting a higher sustainability priority, resource conservation, and the responsible management of mining waste, making it a more favorable alternative to traditional tailing storage facilities. Several industrial uses for the tailings have been suggested to reinforce waste diversion.

Magnesite Mine Waste as a Sustainable Binder for Low-Fines Self-Compacting Concrete: Engineering Property and Ecological Impact

&lt;p&gt;Mine waste management has become a global concern due to its environmental and health impacts, as well as the high cost of disposal. Recent advancements focus on recycling mine waste into resources using effective conservation methods and waste management systems. The building sector, a major consumer of natural resources, has seen studies on using waste materials in concrete. This study examined the feasibility of replacing cement with mine waste in two phases - binary blend (cement + mine waste) and ternary blend (cement + fly ash + mine waste) at 10%, 20%, and 30% doses. The study evaluated fresh properties like slump flow, T50 slump, V-funnel, J-ring, and L-box, and hardened properties like compressive, splitting tensile, and flexural strengths. It also investigated microstructural characteristics, cost, energy impact, and CO2 emissions. The results showed good performance in fresh characteristics for almost all mixtures but failure in hardened properties. The achieved strength was backed by microstructural analysis. Binary blended SCC reduced costs by 5%, energy by 25%, and CO2 emissions by 28%, while ternary blended SCC cut costs by 8%, energy by 32%, and CO2 emissions by 36%.&lt;/p&gt;

The effects of water content on mineralogical and drainage quality dynamics in weathering mine waste rock

Water content plays a critical yet ambivalent role in the physical and geochemical stability of mine tailings and waste rock, but its effects on individual chemical weathering reactions (dissolution and precipitation) and bulk water quality remain poorly understood. We experimented with synthetic waste rock to quantitatively reconcile modal and textural mineralogical parameters (mineral size, association, and liberation) with leachate quality at different water saturation levels (5–100%). Leachate pH consistently decreased from a 13-week average of 6.14 at 100% saturation to 5.37 at 5% saturation. Simultaneously, mineralogical analyses revealed a reduction in the size of carbonate phases over the course of weathering, decreasing from 200 µm to 145 µm as water saturation increased from 5% to 100%, which could be a contributing factor to more alkaline pH in samples with higher water saturation. Total concentrations of iron (Fe) and copper (Cu) in solution increased with lower moisture, with Cu concentrations increasing 24-fold in samples at 5% saturation compared to full saturation. In contrast, arsenic (As) concentration increased with higher moisture levels, which we attribute to reduced galvanic protection of As-bearing pyrite from oxidation. Multivariate statistical evaluation allowed us to uncover correlations between water chemistry and mineralogical data (i.e., sulfide associations or phase perimeters) and to explain chemical differences between samples, particularly those at 100% and 5% water saturation. Our findings underscore the importance of conducting quantitative mineralogical investigations on mine waste materials and considering their stored water content in the formulation of mine waste management strategies.

Управление горнопромышленными отходами арктических промышленных предприятий: охрана окружающей среды и экономика производства

The problems of mining waste management at industrial enterprises and increasing the economy of production are among the most urgent ones, especially for the Arctic ecosystems, characterized by high sensitivity to external factors and the complexity of recovery. The research was conducted on the example of large industrial corporations directly operating in the Arctic, including PJSC PhosAgro, PJSC MMC Norilsk Nickel, Severstal Resource division of PJSC Severstal and PJSC NOVATEK. The key indicators related to waste management for 20182022 were analyzed. The trend of increasing volumes of mining waste in the Arctic was revealed, while the level of its utilization remained practically unchanged. It is proposed to intensify scientific research in the field of rational use of mining waste and to develop technologies for their processing, taking into account the impact on the Arctic ecosystems. It is suggested to create research and production centers for each industrial enterprise using the experience of the balanced “triple helix” model. It is recommended to actively participate in the Interdepartmental Scientific Council of the Russian Academy of Sciences on the development of the mineral resource base and its rational use, created in 2023, to develop the scientific foundations for the extraction and processing of minerals and accelerate import substitution.

Occurrence and mobility of thiolated arsenic in legacy mine tailings

We studied the occurrence of dissolved thiolated Arsenic (As) in legacy tailings systems in Ontario and Nova Scotia, Canada, and used aqueous and mineralogical speciation analyses to assess its governing geochemical controls. Surface-accessible and inundated tailings in Cobalt, Ontario, contained ∼1 wt-% As mainly hosted in secondary arsenate minerals (erythrite, yukonite, and others) and traces of primary sulfide minerals (cobaltite, gersdorffite and others). Significant fractions of thiolated As (up to 5.9 % of total dissolved As) were detected in aqueous porewater and surface water samples from these sites, comprising mostly monothioarsenate, and smaller amounts of di- and tri-thioarsenates as well as methylated thioarsenates. Tailings at the Goldenville and Montague sites in Nova Scotia contained less (<0.5 wt-%) As, hosted mostly in arsenopyrite and As-bearing pyrite, than the Cobalt sites, but exhibited higher proportions of dissolved thiolated As (up to 17.3 % of total dissolved As, mostly mono- and di-thioarsenate and traces of tri-thioarsenate). Dissolved thiolated As was most abundant in sub-oxic porewaters and inundated tailings samples across the studied sites, and its concentrations were strongly related to the prevailing redox conditions and porewater hydrochemistry, and to a lesser extent, the As-bearing mineralogy. Our novel results demonstrate that thiolated As species play an important role in the cycling of As in mine waste systems and surrounding environments, and should be considered in mine waste management strategies for high-As sites.

Analysis of Chloride Contaminant Transport in Tailings Storage Facility Dam (Case Study: Gold Mine in Sumatra)

In the practice of gold mining industry, hazardous waste known as tailings is produced during the ore extraction process. These tailings are typically stored in a dam structure called a Tailings Storage Facility (TSF). The planning and construction of a TSF are critical considerations, as the failure of a TSF can have substantial environmental impacts, pose risks to human safety, and result in industrial losses. Therefore, strict control is necessary in the development of TSFs to minimize the potential negative consequences. This research focuses on the transport of contaminants within a TSF, specifically examining the concentration of chloride contaminants and conducting particle movement analysis. The study utilizes modeling through the GeoStudio SEEP/W program to simulate groundwater flow profiles and the GeoStudio CTRAN/W program to understand contaminant movement over a 100-year period. GeoStudio modeling employs 10 materials: impermeable clay soil, filter sandy soil, transition gravel rock, three mine waste types (Fine, Rockfill, and Rockfill with fine), hard rock bedrock layer, in-situ soil representing the original layer, landslide with colluvial soil, and the tailings itself. Back analysis is employed to iterate model parameters and ensure modeling accuracy against field data, including comparisons with water quality test results and readings from vibrating wire piezometer (VWP) instrumentation. The contaminant transport is influenced by advection-dispersion processes and tends to concentrate within the TSF boundary toward the dam toe over a 100-year timeframe. The analysis emphasizes the influence of advection in contaminant transport and underscores the importance of particle position relative to the groundwater level, with Particle Tracking Analysis shows significant movement within the groundwater flow area. This research provides crucial insights into the dynamics of contaminant concentration, informing better decision-making in TSF planning and management. The findings underscore the imperative of strict control measures to minimize environmental impacts and human safety risks associated with TSFs, thereby advancing knowledge in gold mining waste management.

A Comparison of Artificial Neural Network (ANN) and Long Short-Term Memory (LSTM) in River Water Quality Prediction

River water is a crucial natural resource utilized for various purposes, including agriculture and drinking. Human activities such as mining, industrial discharge, and improper waste management contribute to river water pollution, affecting its quality and posing risks to human health. Monitoring and predicting river water quality are essential for effective management and pollution control. The research focuses on Dissolved Oxygen (DO), and comparing of Artificial Neural Network (ANN) and Long Short-Term Memory (LSTM) to developed prediction models. Evaluation of the models’ performance shows that the ANN model outperforms LSTM in predicting Dissolved Oxygen (DO) concentrations, achieving lower Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE). Although LSTM exhibits lower Mean Squared Error (MSE), the ANN model demonstrates better accuracy in minimizing the average distance between predicted and actual values. The findings suggest that ANN-based models offer good performance in river water quality prediction, with potential for further enhancement through additional variables or model architecture adjustments.

Heavy metals in tailings and soils in the Pb-Zn mining areas of North-west Türkiye and health risk evaluations

Improper mining waste and tailing management in Pb-Zn mining areas (Balya and Koru) in the north-west Türkiye have not been researched sufficiently. Accordingly, concentrations of heavy metal were determined in mine tailing and soils taken from Balya and Koru, and a health risk evaluation caused by heavy metals was performed. Average Cd, Cr, Cu, Mn, Ni, Pb, and Zn concentrations in mine tailings in Balya are 35.2, 17.8, 354.7, 1735, 10, 10089, 3730 mg kg-1 and these values were determined as 9.9, 8.9, 101.5, 1308, 4.5, 1871, 1375 mg kg-1 in the tailings in Koru, respectively. The concentrations of heavy metals in the soil samples taken from both Balya and Koru were determined to be lower. The evaluation of heavy metals’ health risks was performed according to both non-carcinogenic and carcinogenic effects. The primary route of heavy metals in adults and children has been determined by oral intake. For both children and adults, the order of the carcinogenic effects of heavy metals in mine tailings and soils in Balya and Koru was Cd &amp;gt; Pb &amp;gt; Ni &amp;gt; Cr. As the carcinogenic risk values of Cd and Pb for adults and children in mine tailing and soils in Balya were above the limit value, the children’s Cd carcinogenic risk values were found above the limit value in mine tailing and soils in Koru. The mining area in both Balya and Koru poses a risk to human health since it is close to settlements.

Overview Metode Fitoremediasi Dalam Pengelolaan air Tercemar Timbal (Pb)

Wastewater originating from industry varies greatly depending on the type of industry. Industrial wastewater usually contains many toxic and dangerous chemical compounds (B3) and contains heavy metals. Heavy metals are pollutants that have dangerous effects because they cannot be broken down biologically and stable. Heavy metal elements can be distributed on the earth's surface in water, soil and air. Heavy metal waste pollution containing lead (Pb) is a problem for current environmental conditions. Heavy metals are found in almost all types of industrial waste. The increasing number of industries will cause increased pollution of water sources originating from industrial waste. . Therefore, effective and efficient methods are needed to manage lead-contaminated water. Methods that are easy to apply, low cost and environmentally friendly are highly desirable for managing lead-contaminated water so that the concept of good mining practice can be applied to sustainable development. The most efficient and effective method applied for mining waste management is the phytoremediation method. The results of the research state that several plants have a significant and efficient effect in helping the absorption of the metal lead (Pb) contained in water. Great Duckweed (Spirodela Polyrhiza) and Water Hyacinth (Eichhornia crassipes) are plants that are suitable for implementing phytoremediation methods in managing water contaminated with lead (Pb).

The Source, Mobility and Fate of Bismuth (Bi) in Legacy Mine Waste, Yxsjöberg, Sweden

The usage of bismuth (Bi), a critical and strategic raw material, has increased in the last 10 years. At present, the knowledge of Bi geochemistry is too limited to develop accurate mine waste and water management strategies to prevent environmental impact. Therefore, its geochemistry was studied in historical tailings in Yxsjöberg, Sweden. Intact tailings cores and shore samples were geochemically and mineralogically analyzed. Groundwater was sampled between 2016 and 2021 and analyzed for 71 elements and (SO4, F, Cl). The results were correlated with metals and dissolved organic matter (DOC), which have been previously published. The total concentrations, sequential extraction and scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM–EDS) mapping indicated that Bi had been mobilized from the primary mineral bismuthinite (Bi2S3). In the oxidized tailings from both the cores and shore, Bi was hypothesized to have adsorbed to iron (Fe) (hydr)oxides, which prohibited high concentrations of Bi leaching into the groundwater and surface water. Dissolved Bi in groundwater was significantly correlated with DOC. In surface water, dissolved Bi was transported more than 5 km from the tailings. This study indicates that Bi can become mobile from legacy mine waste due to the oxidation of bismuthinite and either be scavenged by adsorption of Fe (hydr)oxides or kept mobile in groundwater and surface water due to complexation with DOC.

Needs and Options for Improving Gold Mining Waste Management Practices for Sustainable Development in Tanzania

The main objective of this study was to evaluate current mining waste management practices and their challenges. This study aimed to identify existing technologies and practices, and to present improvement needs and options for environmentally sustainable practices for mining operations. Other researchers have reported many practices and technologies for managing mining waste, but the efficiency, applicability, and need for customization were not specifically addressed for developing countries. This study used field observations, measurement methods, and laboratory analysis to collect data. This study showed a large amount of mine waste rock compared to the tailings wastewater from gold processing plant produced annually. This comprises approximately 5.2 million m3 of mine contaminated water generated by leaching from the waste rock dump (WRD) and 2.3 million m3 from the tailings storage facility (TSF). The study also identified the use of TSF cut-off trenches for seepage collection, the use of lime to treat acid mine drainage (AMD), the discharge of AMD into the TSF, and the recycling of TSF water as the best practices for managing mining waste. Furthermore, the study also found that the most common environmental problems were caused by TSF water and AMD water. However, mining waste management can be improved by modifying existing practices and adopting cost-effective technologies and practices to control and treat excess mining water.

Tools to improve mine closure: 10 years of research in integration of environment in the mine life cycle

Abstract Mine closure can be approached by several points of view, from the technical, engineering, ecological, up to social and governance aspects. The definition of a good mine closure should cover most, if not all, of these aspects. This article provides a review of technical and engineering-oriented research work as a partial answer to the question ‘what is good mine closure’. The article presents a ten-year research program realized in the framework of a Canada Research Chair in integration of environment in the mine life cycle. Research projects aimed at better planning mine closure and mine site reclamation from the early stages of a mining project life cycle are exposed as possible steps to strive for optimal mine waste management. At the exploration stage, geo-environmental characterization and modeling are proposed as tools to improve mine waste management planification. During mine operations, environmental desulfurization is suggested as a method to reduce environmental risks associated with sulfidic tailings and waste rock. Indeed, research has shown that acid mine drainage and metal leaching can be significantly limited via desulfurization. At the closure stage, desulfurized tailings can be used to replace at least part of natural materials used for reclamation cover systems. Research work done on other types of mine waste, such as waste rock and water treatment sludge, also show good potential for their reuse as closure material. All these tools can be integrated into the mine life cycle to better plan for closure, which ultimately will make mine closure more sustainable.