Search Results (15)

The presence of near-surface cavities poses a significant geohazard due to potential ground subsidence and structural collapse. To mitigate threats to urban stability, this study presents an integrated geophysical framework to locate and characterize abandoned mining galleries and exploitation voids near Linares (Jaén, Spain). The approach combines four complementary techniques: electrical resistivity tomography (ERT), ground-penetrating radar (GPR), frequency-domain electromagnetics (FDEM), and microgravity. The resulting multi-physics responses were cross-referenced with visible surface subsidence features and archival mine plans. Air-filled galleries and shafts generated highly pronounced high-resistivity anomalies. Shallow voids detected at depths of 2–5 m were undocumented in 19th-century mining maps, suggesting older historical origins, whereas deeper ERT profiles and structural disturbance trends (up to 30 m) correlated well with historical records. Within this framework, FDEM provided high-resolution lateral mapping, GPR excelled at resolving ultra-shallow structural boundaries, and ERT characterized deep gallery networks. Crucially, microgravity mitigated inversion non-uniqueness by directly confirming physical mass deficits over the anomalies. This integrated workflow overcomes individual resolution limits, offering a practical tool for land-use planning and early geohazard risk assessment in collapse-susceptible areas. Full article

This paper discusses the viability and efficiency of gravity energy storage (GES) systems utilizing abandoned coal mine shafts in Poland as a new frontier of energy management within the broader framework of sustainable energy transition. After a thorough analysis of shaft infrastructure, economic factors, and regulatory environment, the research demonstrates how GES is in line with circular economy and sustainability principles yet there are certain technical and financial limitations—smaller lifting capacities and expensive adjustments, for instance—that are currently stalling its large-scale adoption. The results highlight the importance of harmonizing such repurposing efforts with the available renewable energy infrastructure and call for aggressive policy, technological, and funding efforts to sustain the conceptual promise with actual fulfilment. Full article

With climate change, more intense weather events are observed, including pressure drops associated with the arrival of atmospheric fronts. These pressure drops are the primary cause of gas emissions from closed mines to the surface, with inactive mine shafts serving as the most likely emission pathways. The most significant emitted gases are carbon dioxide and methane, posing a dual challenge: greenhouse gas emissions and gas-related hazards. This study analyses changes in gas emission intensity in response to short-term (hourly) pressure fluctuations. Additionally, it presents the results of gas emission measurements from an inactive shaft, considering the impact of temperature differences between the air and emitted gases. The findings indicate that gas emissions are subject to inertia, which is crucial for gas monitoring around mine shafts, as emissions may still occur in the early stages of a pressure increase. Furthermore, the results show that temperature differences between the atmosphere and emitted gases could have a major influence on the process. Full article

Gravity energy storage, a technology based on gravitational potential energy conversion, offers advantages including long lifespan, environmental friendliness, and low maintenance costs, demonstrating broad application prospects in renewable energy integration and grid peak regulation. This paper reviews the technical principles, characteristics, and application progress of liquid gravity energy storage (LGES), like pumped hydro storage (PHS) and solid gravity energy storage (SGES) systems—tower-based (T-SGES), shaft-type (S-SGES), rail-mounted (R-SGES), and mountain gravity energy storage (M-SGES). PHS, the most mature technology, is widely deployed for large-scale energy storage but faces significant geographical constraints. T-SGES and R-SGES exhibit higher flexibility for diverse terrains, while S-SGES leverage abandoned mines for resource reuse. Despite advantages such as high round-trip efficiency and extended lifecycle, challenges remain in efficiency optimization, high initial investments, and land utilization. Future development of gravity energy storage will require technological innovation, intelligent dispatch systems, and policy support to enhance economic viability and accelerate commercialization. Full article

This paper describes the characteristics of a thermal response test and presents the results of the test conducted on a borehole at the freezing shaft in Poland. Freezing boreholes are temporary boreholes created to facilitate other geological work, especially for large-diameter mine shafts or other boreholes. Due to their nature, they are abandoned after the necessary work around the mine shaft is completed. The economical point of view suggests that, after their use as freezing boreholes, they should be used for heating if possible. In this paper, the authors aim to suggest that they can be utilized as borehole heat exchangers. Large numbers of freezing boreholes sit idle across the globe while they could be used as a renewable energy source, so creating a new way to obtain heating power in the future should be popularized. The paper includes a description of the implementation method of the thermal response test and the results of the test on a sample freezing borehole intended for abandonment. The test results were interpreted, and the key parameters of the borehole heat exchanger based on the freezing borehole were determined to be satisfactory. The possibilities of other borehole uses are also described. Full article

Turbulent political and economic changes in 1989 caused the gradual decline of the mining industry in the Slovak Republic. Abandoned territorial localities were created, affected by mining activity, without any use with devastated mining objects, or even a certain form of environmental burden. These territorial locations used for mining in the past, unused currently, in varying degrees of devastation, are referred to as mining brownfields. This issue is topical, as there is constant urbanization of new territories. Mining brownfields often represent a certain form of territorial reserve to support tourism development. The present study deals with identifying the tourist potential of the Fedö shaft mining brownfield in the Červenica—Dubník area (Slovakia), which is included in the list of national cultural monuments. The study points out the need for reclamation from the point of view of supporting the development of a tourist destination based on the accessible mining brownfield—the Jozef tunnel—making it possible to use the interaction links of both mining brownfields in the investigated area of tourism. Based on the results of the conducted SWOT analysis, the study presents the quantification of the tourism development support potential of the analyzed mining brownfield. It also includes selected environmental, social, and economic aspects of the reclamation, and the definition of an effective strategy for usage of the examined mining brownfield as a tool to support tourism development. The article concludes a model of effective management of the use of mining brownfields in the field of tourism in Slovakia, which is constructed as open and modifiable in its interaction with the specification of diverse conditions of tourist destinations with integrated mining brownfields, which include old mine works. Full article

The high porosity and high specific surface area of the broken rock mass in abandoned mine goaf make it an excellent thermal storage space. The void structure is an important factor that affects the permeability characteristics of broken rock mass, which determines the efficiency of extracting geothermal water from abandoned mine shafts. To accurately describe the void structure of broken rock mass, the effect of particle erosion on the fracture of rock blocks is considered in this study, based on which an impact-induced strength corrosion calculation model was proposed. Then, this calculation model was embedded into the three-dimensional numerical simulation of broken rock mass for secondary development. A discrete element numerical calculation model was established for broken rock masses with different size grading distributions under water immersion and lateral compression conditions. On this basis, considering the strength erosion effect of impacts, this study investigated the deformation and fracture characteristics of broken rock masses with different size grading distributions and analyzed the evolution laws of porosity in the broken rock masses. The main findings are as follows: The impact effect has a significant influence on the growth of microcracks and the breakage rate of broken rock mass. When the particle size of the broken rock mass differs significantly (size grading as G3), impact-induced strength erosion exerts the greatest impact on the growth of microcracks and the breakage rate. When the particle size of the broken rock mass is uniform (size grading as G1), impact-induced strength erosion minimally impacts the secondary fracturing of the broken rock mass. When the strain of the broken rock sample is less than 0.175, the distribution of microcracks is scattered; when the strain reaches 0.275, microcrack propagation accelerates and exhibits a clustered distribution; and when the strain reaches 0.375, microcracks exhibit a reticular distribution and their connectivity is enhanced. With the increase in deformation, the broken rock mass porosity decreases, and the porosity curve fluctuates along the z-axis with a decreasing trend and gradually becomes more uniform. This study provides a theoretical foundation for assessing the efficiency of extracting and storing mine water with heat in abandoned mine geothermal mining projects. Full article

Acidic mine drainage (AMD) discharged from the abandoned Smolník mine (Pech shaft, Slovakia) contaminates surface water in the Smolník creek due to the decreasing pH and the production of heavy metals. Mixing AMD with surface waters results in an increase in pH, which affects the metal precipitation. Using statistical methods, the effect of pH on the concentration of selected metals (Fe, Mn, Al, Cu and Zn) in the water of the contaminated Smolník creek is described in this work. Polynomial curves were used to identify trends in pH and metal concentration in the surface water. The analysis showed that the second-degree polynomial functions as a candidate for explaining metals’ concentration based on the measured surface water’s pH with a goodness of model fit, based on a coefficient of determination ranging from 0.4 to 0.7 depending on the determined metal concentration and location. Full article

With climate change, more intense weather phenomena can be expected, including pressure drops related to the arrival of an atmospheric front. Such drops of pressure are the main reason for gas emissions from closed mines to the surface, and a closed, empty mine shaft is the most likely route of this emission. Among the gases emitted, the most important are carbon dioxide and methane, creating a twofold problem—greenhouse gas emissions and gas hazards. The work presented in this paper simulated the spread of the mentioned gases near such an abandoned shaft for four variants: model validation, the most dangerous situations found during measurements with or without wind, and a forecast variant for a possible future pressure drop. It was found that a momentary CO₂ emission of 0.69 m³/s and a momentary CH₄ emission of 0.29 m³/s are possible, which for one hour of the appropriate drop would give hypothetically 2484 m³ CO₂ and 1044 m³ CH₄. In terms of gas hazards, the area that should be monitored and protected may exceed 25 m from a closed shaft in the absence of wind influence. The wind spreads the emitted gases to distances exceeding 50 m but dilutes them significantly. Full article

The quest for carbon neutrality raises challenges in most sectors. In coal mining, overcapacity cutting is the major concern at this time, and the increase in the number of abandoned mine shafts is a pervasive issue. Pumped storage hydropower (PSH) plants built in abandoned mine shafts can convert intermittent electricity into useful energy. However, studies on basic theories and key technologies are a pressing issue. Six key scientific problems have been identified in PSH development in abandoned mine shafts that are relevant to China’s national conditions, current resource structure, and relative status of energy storage technologies in China and other countries. It is proposed that the research on pumped storage should move closer to the direction of intelligence, stabilization, and greening, and the construction and development should gradually realize integration, completion, and coordination. The goal is to realize integrated, complete, and coordinated development of PSH in abandoned mine shafts, streamline national policies concerning PSH, drive the co-development of industry, education and research, and achieve the carbon neutrality targets set by China. Full article

The focus of this work is on the evaluation of selected water quality indicators as per the applicable regulations, taking into account European and national legislation and the evaluation of the risk of contamination of surface waters with toxic elements using the contamination factor ($C_f^i$) and the degree of pollution ($C_d$). The studied area of Slovinky is an important ore region, with rich deposits of copper and silver ores that have been mined for centuries. One of the most important remnants of mining activities in this area is the Slovinky tailing impoundment. The sludge pond area has an area of 15 ha, and the height of the dam is 113 m above sea level, which makes the sludge pond one of the tallest water structures in Slovakia. The Slovinský creek was monitored in the years 2010, 2011, and 2019 at five sampling points, which were selected to map the entire length of the water flow from the source to the estuary to the river Hornád. Risk elements (As, Cu, Cd, and Fe) and physicochemical parameters (such as temperature, dissolved oxygen concentration, conductivity, resistivity, salinity, total dissolved solids, NaCl, redox potential, and pH) were included in this study and evaluated according to applicable regulations, taking into account European legislation (Act No. 269/2010 Coll., guideline value WHO 2011). The results of the experimental studies showed that the highest values of As and Cu were measured at the site where drainage waters from the Slovinky tailing impoundment and mining water of the Alžbeta shaft flow into the creek. The concentration of As exceeded the limit value by up to 31 times and the concentration of Cu 16.8–134.5 times. At the same time, the highest values of conductivity, salinity, total dissolved solids, and NaCl were found, and there was no acidification of water at the site that had the highest pollution. Water contamination was assessed based on $C_f^i$ and $C_d$; our findings showed that the surface water from the site of contamination, along the entire length of the stream, was very highly contaminated with risk elements in the order of As > Fe > Cu, and the level of contamination decreased with distance from the site of contamination. Our research shows that seepage of toxic substances from sludge ponds and abandoned mines has caused the requirements for the quality of surface water of the Slovinský creek not to be met. In connection with mining activities, surface streams act as a transport medium through which other components of the environment can be polluted. Full article

The article addresses the issue of mining and industrial waste stored in tailings and heaps in mining areas, and it explores the existing, as well as new, ways of reducing its harmful impact on the environment. On the basis of the Russian experience in mining industry in Ural, it presents a process which makes it possible to eliminate the amassed hazardous waste, retrieve the valuable material (metals) stored in it, and use the remaining waste as backfill in order to both: store it underground (and not on the surface) and prevent the disasters caused by the collapse of the abandoned shafts, thus prolonging the functioning of the mining areas. The process includes preliminary activation treatment of materials found in industrial waste in a disintegrator to protect the environment from toxic pollution. The promising results of the experiment have been discussed, taking into account the complexities of economic evaluation of the idea. Full article

This paper presents the possibilities of adapting active mines to generate green energy after their closure using their resources and/or infrastructure. For this purpose, firstly, the temporal horizon of selected mines in Poland was determined, its basic assumption being the analysis of the current state. In the research, 18 mining plants operating within 12 mines in the Upper Silesian Coal Basin (USCB) were analyzed. The analyzed mines belong to three of the five largest hard coal producers in Poland, and the main object of exploitation is hard coal of energy types. Severe restrictions or even abandonment of further investments in the development of the coal mining industry were taken into consideration (regarding the construction of new shafts or the development of new exploitation levels). When determining the temporal horizon, the challenges that hamper the exploitation based at the levels of natural hazards and depth of exploitation in each mine were considered. Secondly, the criteria for the adaptation of active mines to generate energy are presented. The possibility of using the resources and infrastructural potential of active mines to produce geothermal energy from water, extracting coalbed methane (CBM), and processes of underground coal gasification (UCG) are analyzed. Finally, for a selected example—generating energy from underground coal gasification in Polish mine conditions—a structural analysis of the criteria was performed using the MICMAC method, as the Central Mining Institute has an extensive experience in the development of underground coal gasification trials in coal mines. Based on expert analysis and using structural analysis, the criteria important for UCG were selected. As demonstrated in the article, the MICMAC method can be applied in other scenarios with different criteria to implement new technologies in coal mines. Full article

Three-dimensional groundwater flow around an abandoned mine was simulated to evaluate the effects of backfilling the excavated underground space of the mine on reducing the acid mine drainage (AMD). The conceptual model of the groundwater flow consists of not only variable geological formations but also vertical shafts, horizontal drifts, and the other excavated underground space. The steady-state groundwater flow in both days with high and little rainfall was calculated to calibrate the model. The calculated groundwater levels and flow rate of the AMD agreed with the measured ones by calibrating the hydraulic conductivity of the host rock, which was sensitive to groundwater flow in the mine. This validated model was applied to predict the flow rate of the AMD when backfilling the excavated underground space. The results showed that the flow rate of the AMD decreased by 5% to 30%. This indicates that backfilling the excavated space is one of the effective methods to reduce AMD of abandoned mines. Full article

Cessation of dewatering following underground mine closure typically results in groundwater rebound, because mine voids and surrounding strata undergo flooding up to the levels of the decant points, such as shafts and drifts. SIMPL (Simplified groundwater program In Mine workings using the Pipe equation and Lumped parameter model), a simplified lumped parameter model-based program for predicting groundwater levels in abandoned mines, is presented herein. The program comprises a simulation engine module, 3D visualization module, and graphical user interface, which aids data processing, analysis, and visualization of results. The 3D viewer facilitates effective visualization of the predicted groundwater level rebound phenomenon together with a topographic map, mine drift, goaf, and geological properties from borehole data. SIMPL is applied to data from the Dongwon coal mine and Dalsung copper mine in Korea, with strong similarities in simulated and observed results. By considering mine workings and interpond connections, SIMPL can thus be used to effectively analyze and visualize groundwater rebound. In addition, the predictions by SIMPL can be utilized to prevent the surrounding environment (water and soil) from being polluted by acid mine drainage. Full article