This thesis was written as part of the ExtremEarth research project, which aims to study the impact of extreme weather events on processes at the Earth’s surface. We examined agricultural land in Spodnje Izlake, where we assessed the slope’s susceptibility to mass movements under varying hydrological conditions, particularly fluctuations in the groundwater level caused by extreme rainfall. Based on publicly available spatial, geological, and hydrological data, as well as previously conducted field surveys, we characterized the geotechnical conditions in the area. We conducted laboratory tests on the collected samples to determine natural moisture content, Atterberg plasticity limits, grain size distribution, and drained shear strength. We analyzed slope instability using the Slide2 software with the GLE/Morgenstern-Price method across three profiles (V1, V2 and V3), under two scenarios for the thickness of the weathered soil layer above the bedrock (10 m and 20 m) and two combinations of soil shear strength parameters, assuming a conservative estimate of the highest possible groundwater level. The results show the highest safety factors in profile V2 and the lowest in profile V3, where, for the worst combination of shear parameters and groundwater at the surface, the safety factor was 0.790, indicating potential slope instability. As no signs of past or active slope mass movements have been observed in the area, we consider this to be a conservative assessment of the situation, which nevertheless highlights the increased vulnerability of profile V3. The thickness of the weathered soil layer within the range under consideration did not significantly affect the results. We recommend further investigations and surveying to determine the thickness of the weathered layer more precisely and to carry out long-term monitoring of the groundwater level.
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