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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 explores ethical investment practices among Catholic institutions in Indonesia. As a relatively rare area of inquiry, the research investigates the extent to which Catholic institutions have sought to translate the principles of Catholic Social Teaching (CST) into the field of investment. Data were collected through interviews with key participants from three dioceses and six congregations. The findings reveal that these institutions have endeavored to implement ethical principles derived from CST. Due to limitations in their capacity to conduct screening and analysis of various investment options, they have adopted a strategic approach by utilizing the services of an investment consultancy team from the Indonesian Bishops’ Conference (KWI). Drawing on Max Weber’s theoretical framework, this practice is interpreted as a form of social action grounded in “value-rationality.” Thus, investment activities pursued rationally for financial gain are framed within the values of CST. In this way, Catholic institutions have sought to establish faith-based ethical investment practices.

Slope stability is a key concern in open-pit mining due to its impact on safety and operational efficiency. Mine X, located in Kalimantan Island, faces landslide risks on its high wall slopes. This study aims to model slope stability and determine safe and economical slope geometry. The analysis was performed using the Limit Equilibrium Method (Bishop Simplified), both analytically and numerically, through Slide 6.0 software by Rockscience Inc. Input data were obtained from five geotechnical investigation points provided by PT.X, including cohesion, internal friction angle, and saturated unit weight. Two lithologies were analyzed—claystone and sandstone—with slope height variations (5 m, 10 m, 15 m) and angles (26°, 45°, 51°, 59°), under dry and saturated conditions. Simulation results show that the factor of safety (SF) decreases with increasing slope height and angle, especially under saturated conditions. Sandstone demonstrates better stability than claystone. The recommended optimal slope geometry is 10 meters in height with a 59° angle, yielding a SF ≥ 1.25 and aligning with the PC-400 excavator's cutting capability. This study provides a technical reference for designing safe slopes that support mining productivity.