This paper presents the slope stability analysis for the current as well as projected (final) geometry of waste dump Sandstone Open Pit “Osielec”. For the stability analysis six sections were selected. Then, the final geometry of the waste dump was designed and the stability analysis was conducted. On the basis of the analysis results the opportunities to improve the stability of the object were identified. The next issue addressed in the paper was to determine the proportion of the mixture containing mining and processing wastes, for which the waste dump remains stable. Stability calculations were carried out using Janbu method, which belongs to the limit equilibrium methods.

In this paper, an attempt has been made to investigate the possibility of using coal sludge to seal a landfill site by presenting the results of their compressibility and permeability tests. Coal sludge is a fine-grained waste from the coal enrichment process, and its permeability is also highly dependent on its degree of consolidation. The tests were carried out in a Rowe Cell, making it possible to determine the water permeability coefficient more precisely by determining the degree of the material consolidation during testing. The test was carried out using backpressure conditions. The test procedure in the Rowe Cell consisted of the following three steps: saturation, consolidation, and filtration. The coal sludge was taken directly from the filter presses as a by-product of the fines’ coal enrichment process. The paper presents the results of the individual stages performed in a Rowe Cell. The consolidation coefficient was determined using three different methods (Casagrande, Taylor, and Robbinson methods). The permeability coefficient was measured by the indirect and the direct method, the results of both were compared. The results (k < 10⁻⁹ m/s) indicated that the value of the permeability coefficient responds to the value for isolating barrier materials.

Coal sludge, a fine-grained by-product of hard coal benefit, comprises a mixture of coal particles and mineral and organic matter. Generated during sedimentation and dewatering processes in preparation plants, it is typically recovered as a semi-solid filter cake. The material has potential applications in energy production and, with appropriate processing and stabilization, could be utilized in geotechnical facilities. The strength properties defined by the internal friction angle and cohesion, as well as the deformation properties expressed by compressibility, are among the most important mechanical characteristics of soil. This article presents tests of coal sludge, for which the internal friction angle, cohesion, and oedometric primary and secondary moduli were determined. The material was prepared at its optimum moisture content and maximum dry density prior to testing. In the direct shear test, using a shear box of 6 × 6 cm, each sample was consolidated for 24 h under the applied vertical stress, under which it was subsequently sheared. The shear rate was constant at 0.01 mm/min, and the test was conducted up to 10% horizontal deformation. The vertical stresses applied ranged from 50 to 200 kPa. In the oedometer test, samples were prepared to fit the dimensions of the oedometer ring, and each subsequent load stage was applied after 24 h. The range of vertical stresses in this test was from 12.5 to 400 kPa. The results of the direct shear test (φ = 24°, c = 28 kPa) are similar to the strength parameters typically obtained for medium-cohesive soils, such as sandy silt (φ = 22°, c = 25 kPa. The results of the compressibility tests (0.89 MPa < M₀ < 6.35 MPa) correspond to values characteristic of organic soils, for example, organic silts (0.5 MPa < M₀ < 5 MPa). Moreover, analysis of the consolidation curves showed that up to a vertical stress of 100 kPa, coal sludge does not exhibit rheological behavior. The obtained results indicate that coal sludge, when compacted up to its optimum moisture content and to an adequate dry density, can be effectively utilized for geotechnical applications, such as the construction of isolation barriers, as a component of geotechnical mixtures, or as a sealing material for the reclamation of post-mining areas.

The growing availability of spatial data from remote sensing, laser scanning (LiDAR), and photogrammetric techniques stimulates the dynamic development of methods for the automatic detection and classification of topographic objects. In recent years, both classical machine learning (ML) algorithms and deep learning (DL) methods have found wide application in the analysis of large and complex data sets. Despite significant achievements, literature on the subject remains scattered, and a comprehensive review that systematically compares algorithm classes with respect to data modality, performance, and application context is still needed. The aim of this article is to provide a critical analysis of the current state of research on the use of ML and DL algorithms in the detection and classification of topographic objects. The theoretical foundations of selected methods, their applications to various data sources, and the accuracy and computational requirements reported in the literature are presented. Attention is paid to comparing classical ML algorithms (including SVM, RF, KNN) with modern deep architectures (CNN, U-Net, ResNet), with respect to different data types such as satellite imagery, aerial orthophotos, and LiDAR point clouds, indicating their effectiveness in the context of cartographic and elevation data. The article also discusses the main challenges related to data availability, model interpretability, and computational costs, and points to promising directions for further research. The summary of the results shows that DL methods are frequently reported to achieve several to over ten percentage points higher segmentation and classification accuracy than classical ML approaches, depending on data type and object complexity, particularly in the analysis of raster data and LiDAR point clouds. The conclusions emphasize the practical significance of these methods for spatial planning, infrastructure monitoring, and environmental management, as well as their potential in the automation of topographic analysis.

The paper divides engineering methods that can be applied to improve geotechnical parameters of soils at the site of their dysfunctions causing loss of stability, bearing capacity, etc. The paper identifies geo-engineering studies necessary to analyse geotechnical conditions. Analyses of stability of the described railway line section running through area of the Western Carpathians are discussed. Results of field and laboratory tests are presented. The lack of stability of the analysed section results in the need to carry out geo-engineering reinforcement works to improve the geotechnical parameters and to protect the slope against landslides.