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This study aims to determine the soil classification of rock disintegration products based on the Unified Soil Classification System (USCS) and analyze its relation to sample depth variations on the lowwall slope of Pit North, PT Karya Putra Borneo, Kutai Kartanegara Regency, East Kalimantan. Soil samples were obtained through the Slake Durability test, simulating rock weathering from wetting and drying cycles, producing fine particles classified as weathered soil. These samples were analyzed for physical properties using Atterberg Limits tests and Grain Size Analysis. Observation point coordinates were X 508523.011 m, Y 9922791.186 m, at an elevation of 87.548 m. Drilling indicated soil material at 0–1.5 m depth; claystone with coal fragments at 2.97–4.44 m; siltstone with coal fragments at 4.44–10.55 m; and claystone at 12.05–29.36 m. USCS classification showed the materials were dominated by fine-grained soils: clay (CL) and silt (ML), with minor silty sand (SM). Correlation with borehole depth revealed no significant changes in soil classification, indicating that depth variations primarily affect soil physical properties rather than its classification type.  

Travertine is a non-marine carbonate rock precipitated from calcium- and bicarbonate-rich waters, commonly associated with hot springs, streams, and lakes in tectonically active regions. This study presents a systematic literature review of travertine deposit characteristics, encompassing mineralogical composition, geochemical signatures, petrographic textures, morphological types, isotopic properties, biotic–abiotic controls on formation, early diagenesis, and petrophysical implications. The synthesis indicates that travertine is predominantly composed of calcite, with aragonite forming under conditions of elevated temperature, high Mg/Ca ratios, and rapid CO₂ degassing. Travertines display exceptional textural diversity, ranging from abiotic crystalline crusts to microbially mediated fabrics such as shrub, peloidal, and stromatolitic structures. Major morphologies include fissure ridges, mounds, terraces, cascades, and slopes, strongly governed by tectonic setting, topography, hydrology, and substrate geology. Stable isotopes (δ¹³C and δ¹⁸O), strontium isotopes, trace elements, and REE patterns effectively constrain fluid provenance and distinguish thermogene from meteogene travertines. Microbial activity plays a crucial role in biomineralization, influencing precipitation rates, crystal morphology, and lamination patterns. Early diagenetic processes occurring during active deposition may significantly modify primary fabrics and geochemical signals. Travertine petrophysical properties exhibit distinctive porosity–velocity relationships, making them valuable analogues for subsurface carbonate reservoirs. This review highlights that travertines record complex interactions among physical, chemical, biological, and geological processes and hold significant value for paleoenvironmental reconstruction and carbonate reservoir studies.

The evaluation of haul road geometry at PT Trubaindo Coal Mining was conducted to ensure that the haul road from the stockroom to the jetty meets applicable technical standards, thereby supporting the smoothness, safety, and efficiency of coal transportation activities. This study aims to analyze the conformity of haul road geometric parameters, including straight road width, curve width, curve radius, cross slope, longitudinal grade, and superelevation, based on the standards of AASHTO 7th Edition and Kepmen 1827 of 2018. The research method employed field measurements using a Terrestrial Laser Scanner (TLS), followed by data processing using Maptek and Surpac software. The obtained data were then compared with the applicable standards to determine the level of conformity of the haul road geometry. Based on field measurements, the average values obtained were 14.99 m for straight road width, 18.45 m for curve width, 0.22 m for cross slope, 6.97% for grade, 223.51 m for curve radius, and 1.40 m for superelevation. Furthermore, based on calculations and analysis referring to AASHTO 7th Edition and Kepmen 1827 of 2018, and considering the largest haulage equipment used (Volvo FMX 480), the ideal haul road geometry values were determined as follows: 13 m for straight road width, 17 m for curve width, 124 m for curve radius, 0.26 m for cross slope, 1 m for superelevation, and 6% for grade based on PT Trubaindo Coal Mining standards.

Background: Sambirejo is prone to landslides due to steep slopes and heavy rainfall, but community preparedness remains low due to limited awareness campaigns, the absence of emergency response teams, minimal reforestation, and a lack of knowledge about local disaster evacuation procedures. Objective: To determine the preparedness of residents in facing landslides in Dukuh Secang. Method: The method used was a direct survey with a sample size of 57 respondents and used Non- probability Sampling with the Purposive method. Results: The study shows that based on the characteristics of the respondents, the majority are young adults aged 26-35 years (26.3%), the majority are female with 33 respondents (57.9%), and the majority have a high school education (43.9%). The overall results indicate that the preparedness of residents in Dukuh Secang Jetis Sambirejo Sragen is in the “Very Prepared” category. The preparedness indicators showed a high level of knowledge (64.9%), policies and guidelines (94.7%), emergency plans (94.7%), warning systems (94.7%), and resource mobilization (91.2%). Conclusion: The preparedness of residents in facing landslides in Dukuh Secang, Jetis Sambirejo Village, Sragen is in the very ready category with a preparedness index score of 78.9%.

Urban development has resulted in an increase in impermeable surfaces, increasing the risk of runoff inundating the road network. This situation occurs in the drainage system on Jl. Letjend S. Parman, Jl. Emo Kurniaatmaja, and Jl. Pulau Banda, Pasirkareumbi Village, Subang Regency. This study aims to evaluate the hydraulic performance of existing channels and develop redesign guidelines to reduce the risk of local flooding. The methods used include hydrological analysis of daily maximum rainfall data from the Subang rainfall station, rainfall frequency analysis using the Generalized Extreme Value (GEV) distribution, Intensity-Duration-Frequency (IDF) curves, and hydrological and hydraulic simulations using the Storm Water Management Model (SWMM). Model parameters include sub catchment area, rainfall intensity, time of concentration, infiltration using the Curve Number method, channel dimensions, cross-sectional shape, channel material, and the Manning coefficient. The results indicate that the GEV distribution provides a good fit for determining design rainfall. Based on the typology of a metropolitan city and a catchment area of ​​26.04 ha, the modeling period is 2 to 5 years. The SWMM simulation results indicate that some channel segments have very high flow velocities, potentially causing scour, while other segments have very low velocities, potentially causing sedimentation. This confirms the need for evaluation and restructuring of channel dimensions and slopes to improve the hydraulic performance of road drainage and reduce localized flooding.

Slope stability studies are crucial in determining the sustainability and operational safety of mining activities. This research was conducted to analyze the correlation between rock porosity and Unconfined Compressive Strength (UCS) results, as well as the corrleations between Point Load Index (PLI) and Unconfoned Compressive Strength (UCS) results. These two correlations form the primary components of the study. Three types of rock were tested claystone, coal, and siltstone. The results of the study are as follows for the correlation between porosity and Unconfoned Compressive Strength (UCS), claystone yielded a coefficient of determination (R2) of 0.32 is classified as weak correlation, with the linear regression equation Y=-0.11X+6.98. Coal yielded an (R2) of 0.56 is classified a moderate correlation, with the equation Y=-1.98X+103.77. Siltstone yielded an (R2) of 0.86 is classified a strong correlation, with the equation Y=-0.38X+20.02. Regarding the correlation between Point Load Index (PLI) and Unconfoned Compressive Strength (UCS), claystone achieved an (R2) of 0.12 is classified a very weak correlation, with the linear regression equation Y=8.91X. Coal achieved an (R2) of -0.27 is classified a very weak correlation, with the equation Y=27.87X. Lastly, siltstone achieved an (R2) of -0.45 is classified a very weak correlation, with the linear regression equation Y=24,90X.

Abstract: Padukuhan Karangrejek, Karangtengah, Imogiri, Bantul, is a sloping area prone to landslides due to high rainfall, soil erosion, and vegetation degradation. Landslides often threaten the safety of residents, damage infrastructure, and disrupt the sustainability of the local environment and economy. This study aims to apply bioengineering through the planting of slope-stabilizing plants to improve slope resistance to landslides using an environmentally friendly and sustainable nature-based approach. The methods included surveying planting locations, preparing planting holes, making tree marker boards, and participatory phased planting with the community. The types of plants used were Munggur, Soursop, Jackfruit, and Teak, which have strong root systems to strengthen soil structure and reduce erosion. The results showed an increase in soil cohesion through root penetration, a reduction in rainwater runoff, suppression of erosion, and a decrease in the risk of subsequent landslides. The positive impacts included increased soil water retention, improved soil fertility, community empowerment in disaster management, and economic added value from fruit and timber crops. Conclusion The application of bioengineering with Munggur, Soursop, Jackfruit, and Teak trees is an effective, inexpensive, and sustainable solution for landslide mitigation in Karangrejek Hamlet. Recommendations include monitoring growth periodically, expanding planting to other slopes, and integrating the program into the village's disaster resilience plan for long-term sustainability.

Landslides in the Giritengah Catchment Area are influenced by several factors, including geological conditions, rainfall intensity, geomorphology, soil characteristics, and inappropriate land use practices, all of which affect regional spatial planning and environmental stability. This study presents a literature review that analyzes landslide vulnerability, evaluates the impact of land use changes, and proposes integrated Soil and Water Conservation Techniques (SWCT) to support sustainable land management. The analysis applies Geographic Information System methods using thematic map overlays such as rainfall distribution, slope gradient, geological structure, and land use patterns. The results show that areas categorized as having high landslide vulnerability cover 44.02% or approximately 158.69 hectares of the catchment area, while areas with very low vulnerability account for only 0.12% or about 0.79 hectares. Land use conversion, particularly mixed dryland agriculture, has increased landslide risk by reducing slope stability and increasing surface runoff. To address this issue, conservation strategies are recommended, including vegetative measures such as greening 38.51 hectares in settlement areas and implementing agroforestry systems across 218.48 hectares. In addition, structural measures such as three dam retainers and twenty gully plugs are proposed in both protected and cultivation zones to support disaster mitigation and align with regional spatial planning policies.

Mine slopes play a crucial role in ensuring the safety and sustainability of mining activities. Continuous mining operations can alter slope conditions, thereby increasing the potential for instability and slope failures. Slope stability is influenced by the balance between resisting forces and driving forces acting on the rock mass. When the resisting forces are smaller than the driving forces, the slope becomes unstable and failure may occur. Therefore, slope stability analysis is essential to prevent landslide hazards, as it directly affects occupational safety, equipment security, other assets, and overall production continuity. These conditions have encouraged PT Insani Bara Perkasa to develop a more accurate and real-time slope monitoring system. The application of radar-based monitoring was initiated using the CHCNAV PS-2000 system. This study aims to analyze the deformation behavior of mine slopes using radar technology. Data acquisition was conducted at Pit K1 Mahakam, PT Insani Bara Perkasa, covering Area 1 South, AR 2 South, AR 3 South, AR 5 South, AR 6 South, AR 7 West, AR 8 West, AR 9 South, AR 13 South, as well as TA-2, TA-3, and TA-6 areas. The study was carried out from November 2025 to December 2026. The analysis results indicate that most monitoring points are in stable conditions, with indications of a progressive phase observed in the AR 6 South area.

The stability of disposal slopes is a critical aspect of open-pit mining operations because it directly affects operational safety and the continuity of overburden dumping activities. Disposal areas composed of overburden materials generally exhibit heterogeneous characteristics, particularly when soft materials such as mud are present, which can significantly reduce slope stability. Therefore, a comprehensive slope stability evaluation is required prior to further disposal development. This study aims to assess the stability condition of a disposal slope under initial conditions, evaluate the influence of material conditions, and analyze the effectiveness of counterweight application in improving both the safety factor and disposal capacity. The research methodology involved the collection of primary and secondary data, including slope geometry, lithological conditions, and the physical and mechanical properties of disposal materials obtained from laboratory testing and company technical data. Slope stability analysis was performed using the limit equilibrium method with the assistance of geotechnical software, taking into account groundwater conditions and operational loading. The analysis results indicate that the initial disposal condition yielded a safety factor of 0.718, indicating an unstable slope condition. After simulating the removal of mud material, the safety factor increased to 0.907 but remained below acceptable stability criteria. The application of a counterweight significantly improved slope stability, resulting in a safety factor of 1.498. Further optimization through slope geometry redesign produced a final safety factor of 1.101, which satisfies the requirements stipulated in KEPMEN ESDM No. 1827 K/30/MEM/2018. Additionally, the redesign increased the disposal capacity from 119,507,864.23 LCM to 119,682,378.22 LCM, representing an increase of 174,513.99 LCM. These results demonstrate that counterweight application combined with geometric optimization is effective in enhancing both slope stability and disposal capacity.

Malino City in Gowa Regency plays a crucial ecological role as a water catchment area, yet it currently faces the threat of land degradation due to land-use conversion and erosion in hilly areas. This community service activity aims to implement soil conservation while enhancing the economic potential of local residents through the planting of productive fruit tree seedlings. The methods employed include educational socialization, training on planting techniques for sloped land, and the distribution of superior fruit tree seedlings (avocado, durian, and orange). The results indicate an increase in community understanding regarding the importance of permanent vegetation in maintaining soil stability. A total of [Mention number] tree seedlings were planted with the active participation of local farmer groups. In conclusion, the integration of ecological and economic aspects through productive trees creates a sustainable conservation system by providing direct financial benefits to the community, thereby increasing their motivation to preserve the environment in the Malino region.

Guaranteeing the geotechnical stability of slopes is an absolute prerequisite for the sustainability of open pit mining operations, considering the potential for multidimensional losses due to slope failure. The specific geological conditions at PIT B1 PT. Pancaran Surya Abadi, which is composed of sedimentary rocks (coal, sandstone, and claystone), are susceptible to degradation and softening, especially due to high rainfall that causes an increase in pore water pressure and a decrease in rock shear strength. This study aims to analyze the stability of highwall slopes using the Morgenstern-Price Method to determine the Safety Factor (SFF) value according to Ministerial Decree number 1827 K/30/MEM/2018, and continued with a semi-quantitative risk analysis. The analysis results show that the initial slope has a static SFF of 0.77 (Not Safe). After redesign, the recommended optimal single slope geometry is: sandstone (Height 5 m, Angle 20°, Berm 5 m) and claystone (Height 10 m, Angle 60°, Berm 5 m). This redesign resulted in a FK of 1.34 (Safe). Sensitivity analysis to groundwater level rise (GTL) showed that the GTL value remained safe (GTL ≥1.30) up to a 30% increase in GTL. However, a 40% to 80% increase in GTL caused the GTL to decrease (1.28–1.21), classified as Medium Risk. A 100% increase in GTL drastically reduced the GTL to 1.05, classified as High Risk. This study emphasizes the need for close monitoring and additional drainage to maintain the long-term stability of slopes under the influence of rainfall.  

In engineering practice, various methods have been implemented to stabilize landslide-prone slopes, one of which is the use of bore piles. Bore piles are structures that hold back soil and make slopes more stable by reinforcing the ground inside them. However, the application of bore piles in landslide mitigation presents its own challenges, making it essential to identify and anticipate potential issues that may arise in field engineering practice. Bore piles are installed vertically, either parallel or staggered, at specific spacing and are often combined with capping beams and struts to resist soil movement and provide lateral restraint. This method is commonly applied to high-risk slopes or critical infrastructures such as roads, bridges, and buildings. Anticipation strategies in engineering practice consist of three stages: planning, implementation, and long-term maintenance, with this study focusing specifically on anticipation strategies during the implementation stage. Although bore piles serve as an effective solution to reduce landslide risk, their success depends heavily on proper planning, construction execution, and maintenance. Issues such as soil conditions, construction quality, and external factors must be addressed through a comprehensive engineering approach.

Mining sequence design is one of the important stages in open pit mining activities that aims to organize the excavation stages so that production activities run effectively, efficiently, and in accordance with the established targets. This research was conducted at PT Putra Perkasa Abadi Site SKS with the aim of designing a mining sequence in January and February 2025. The methods used include analysis of topographic data, geology, pit design, and monthly production targets. The data was processed using mining software to determine the excavation sequence based on elevation, overburden volume, and coal reserves. The design results show that the total planned overburden and coal volume is able to meet the company's production targets by considering slope stability and the efficiency of digging and loading equipment. In addition, the resulting sequence design also takes into account aspects of work safety and field operational conditions, such as mine road access and drainage systems. With a structured design, it is expected that mining activities during this period can run according to schedule, minimize operational obstacles, and support the achievement of production targets and cost efficiency at PT Putra Perkasa Abadi Site SKS.

A research about study of sandstone slope stability using the Bishop Simplified method in Uu Samarinda has been conducted. This study was conducted to analyze the rebound number values of sandstone slopes, evaluate their stability level, and calculate the safety factor using the Bishop method. The results showed that the rebound number values were 22.34 at point 1, 19.83 at point 2, and 18.07 at point 3. The Uniaxial Compressive Strength (UCS) values at the observation points were 1.90 MPa, 1.62 MPa, and 2.21 MPa, respectively. Geological Strength Index (GSI) evaluation indicated a rating of 80–85, demonstrating intact/massive rock structure, fresh and unweathered rock surfaces, and very good rock quality. Based on the Bishop method analysis, the slope factor of safety in 6.525  with a probability of failure is 0.000%, indicating that the sandstone slope in Ulu Samarinda is highly stable even under external pressures such as heavy rainfall or minor earthquakes. This study provides crucial information on the mechanical characteristics and stability of sandstone slopes in ulu Samarinda, which can serve as a reference for technical planning, geotechnical risk mitigation, and the sustainable development of safe areas.

This study aims to analyze the level of flood hazard in Baturaja Barat District, Ogan Komering Ulu Regency, by applying a spatial approach using Geographic Information Systems (GIS) through the overlay method. The analysis was carried out by integrating six main physical parameters, namely rainfall, land use, elevation, slope, river density, and soil type. Each parameter was assigned a score and weight according to its influence on flood potential and subsequently processed spatially to produce a flood hazard map. The results indicate that the Baturaja Barat District area is classified into three hazard levels: low (3.25%), moderate (70.64%), and high (25.84%). Areas with high hazard levels are predominantly characterized by densely populated settlements situated at low elevations and in close proximity to river networks, particularly in Tanjung Karang, Air Gading, Talang Jawa, Karang Agung, and surrounding villages. These findings highlight that land-use changes, topographic conditions, and the distribution of river networks play significant roles in increasing flood risk. The results of this study are expected to serve as a foundation for spatial planning, the strengthening of disaster mitigation policies, and the enhancement of community preparedness against flood hazards in the region.

The stability of slopes in open-pit coal mining in Indonesia is significantly influenced by geological faults, which are a major factor causing slope failures. This study aims to examine the impact of faults on slope stability by conducting a systematic literature review of 25 scientific publications from 2018 to 2025. The results indicate that faults and fault zones consistently reduce rock mass integrity through several mechanisms, including stress concentration in weak zones, the formation of preferential sliding surfaces, amplification of hydro-mechanical effects from groundwater and rainfall, and the reduction of rock strength parameters. Case studies in Kalimantan and Sumatra confirm these mechanisms with slope failures aligning with fault orientations. Kinematic and numerical analyses using the Limit Equilibrium Method (LEM), Finite Element Method (FEM), and Distinct Element Method (DEM) show a reduction in the safety factor (SF) by up to 36% on slopes affected by faults. Practical recommendations include continuous monitoring using Slope Stability Radar (SSR), optimization of slope geometry with angles < 18° in fault zones, groundwater control, reinforcement with anchors and bolting, and UAV-based discontinuity mapping for hazard zoning. This study concludes that managing slopes in fault zones requires an integrated approach combining detailed geological investigation, multi-method numerical analysis, real-time monitoring, and specific mitigation design.

Tax fairness has become a central concern in improving individual taxpayer compliance in Indonesia, particularly amid increasingly complex regulations and declining public trust in fiscal institutions. This study stems from the urgent need to understand how individual taxpayers interpret the notion of tax fairness and how these interpretations shape their willingness to comply. The primary objective is to explore the underlying dimensions of tax fairness procedural, distributive, and interactional and to explain how these dimensions relate to the development of voluntary compliance. Employing an interpretive qualitative approach, this research relies on in-depth interviews with 15 individual taxpayers located in Jakarta, Yogyakarta, and Medan, selected through purposive sampling. The data were examined using Interpretative Phenomenological Analysis (IPA) to uncover recurring themes and the subjective experiences shared by participants. Findings reveal that perceptions of procedural and interactional fairness exert the strongest influence on compliance behavior, while distributive fairness is often viewed negatively due to perceived inequality in public benefit allocation and the complexity of tax rules. Trust in government and social morality emerge as critical mediators linking fairness perceptions to voluntary compliance. The study contributes theoretically by integrating Equity Theory, Tax Morale Theory, and the Slippery Slope Framework within the Indonesian cultural context, emphasizing that tax fairness forms the moral foundation of voluntary compliance. Practical implications highlight the need for equitable public services, stronger fiscal transparency, and value-based tax education. Future research is encouraged to adopt mixed-methods designs to provide deeper quantitative insights into the relationship between fairness, trust, and tax compliance across diverse social settings.

This literature study evaluates the accuracy of the Slope Mass Rating (SMR) method for coal mine slope stability in Indonesia through a systematic descriptive synthesis of 25 empirical studies from 2020 to 2025. The objectives of the study were to identify the level of SMR prediction accuracy, factors affecting the method's performance, and modifications required for local Indonesian conditions. The research method involved a systematic search with inclusion criteria for empirical studies reporting SMR and/or Safety Factor (SF) values ​​for coal mines and associated slopes in Indonesia. Quantitative analysis showed a range of reported SMR values ​​between 41 and 96 with a median of 72, while SF values ​​ranged from 1.137 to 4.09 for normal operational conditions. The synthesis results indicated that SMR provides a consistent stability classification for initial slope design and failure mode identification (planar, wedge, toppling), with historical validation showing a correlation of up to 91.23% between SMR-based hazard zoning and actual field events in some cases. Key limitations include dependence on discontinuity data quality, sensitivity to groundwater conditions and tropical weathering, and variation in the interpretation of adjustment factors F1-F4. Modifications such as NAAF23 and integration with numerical modeling have been shown to improve prediction reliability. It is recommended that coal mining practitioners combine SMR with kinematic analysis and limit equilibrium modeling as standard operating procedures, and develop adjustment factors specific to Indonesian geological conditions. Further research should focus on standardizing parameter reporting and cross-site quantitative validation to enable more robust statistical meta-analyses.  

This study formulates a design concept for the Beach Tourism Resort Area in Botubarani Village by applying tropical architecture that responds to coastal climatic conditions while enhancing the quality of visitor experiences. The research integrates principles of thermal comfort, environmental sustainability, and the ecological potential of coastal environments as the basis for creating climate-adaptive and environmentally responsive tourism areas. The methodology includes site analysis, field observation, climatological assessment, and a literature review related to tropical architecture and coastal tourism design. The collected data were used to determine building orientation, mass layout patterns, visitor capacity, materials, vegetation, and utility systems appropriate for humid tropical climates. The findings show that the site’s position between the sea and the mountains, combined with full-day sun exposure, requires design strategies that maximize cross-ventilation, utilize sloped roofs, provide natural shading, and apply local materials such as wood, bamboo, and red brick. The large spatial needs based on visitor capacity projections are accommodated through a flexible cluster layout that supports visual and functional connectivity between buildings while incorporating green open spaces to enhance microclimate comfort. The utility system is designed using sustainability principles through greywater–blackwater separation, infiltration wells, and recycling-based waste management. This study confirms that the application of tropical architecture in coastal tourism areas can improve thermal comfort, energy efficiency, and environmental sustainability. These findings guide developing tropical tourism area designs that are more adaptive to climate change and more responsive to visitor needs.