I In the design of foundation soil structure and soil bearing capacity, proper planning is crucial, as the bearing capacity significantly influences the thickness of the subgrade layer in pavement design. various methods are used to test soil bearing capacity, such as the standard penetration test (spt), among others. this study aims to analyze geological conditions for dam foundation planning in the bengkayang area using the unconfined compressive strength (ucs) and standard penetration test (spt) methods. the spt method is used to determine the penetration resistance parameters of soil layers in the field, which are essential for soil layer identification and foundation design. the results from spt tests are correlated with ucs tests to determine the compressive strength of rocks. this study involves several stages, including selecting the survey location, collecting primary and secondary data, and processing and interpreting the data. the research findings are expected to provide recommendations regarding rock usage, structural design, and mitigation measures based on the conducted survey results. additionally, this study aims to contribute to the development of engineering geology, particularly in the fields of mining and foundation engineering. this research not only focuses on analyzing soil and rock conditions but also considers geological factors that affect the stability of dam foundations. by utilizing the ucs method, the strength characteristics of rocks can be determined in detail, including the maximum compressive strength that rock materials can withstand. this is crucial to ensure that the planned dam structure can endure both static and dynamic loads while also anticipating potential failures due to unfavorable soil and rock conditions. through this combined approach, the research findings are expected to provide practical technical solutions for dam project planners and executors, as well as assist in formulating mitigation strategies against geotechnical risks such as landslides, erosion, and soil deformation. the analysis is conducted by examining the subsurface stratigraphic profile obtained from spt tests and evaluating the physical and mechanical properties of rocks through ucs tests. to support this evaluation process, secondary data, such as geological maps and local seismic data, are also utilized to enhance the analysis