Alluvial beds are intimately associated with electrical properties related to soil types, including clay mineral content, porosity, and water content. The hydraulic property governs water movement and storage in alluvial beds. This study revealed electrical resistivity and hydraulic properties in space and time in relation to the hydrogeological data, groundwater pumping, and rainfall infiltration into the alluvial bed located in Daesan-myeon, Changwon City. An electrical resistivity survey with electrode spacings of 2 and 4m using a dipole-dipole array indicates that electrical resistivity changes in the alluvial bed depend on groundwater pumping and rainfall events. Additionally, rainfall infiltration varies with hydraulic conductivity in the shallow zone of the alluvial bed. The 2 m electrode spacing survey confirms that electrical resistivity values decrease at shallow depths, corresponding with rainfall and increased water content in the soil, indicating rainfall infiltration approximately 1-2 m below the land surface. The 4m electrode spacing survey reveals that hydraulic conductivity (K) values and electrical resistivity (ρ) values display an inverse relationship from the surface to the water table (approximately 9 m) and at deeper levels than the water table. Notably, ρ values are impacted by pumping around the depth of the water table at 9 m. This study suggests that time-lapsed electrical resistivity surveys in space and time could be effective tools for detecting the impact of rainfall and pumping, as well as hydraulic conductivity in shallow alluvial beds.

Introduction
    Geological and hydrogeological setting
Methods
    Method of electrical resistivity survey
    Cross-correlation analysis
Results
    Electrical resistivity change in space and time
    Result of cross-correlation function analysisbetween electrical resistivity and depth to water
Discussion
Conclusions
Acknowledgment
References

• Woo-Ri Lim(Institute of Sustainable Earth and Environmental Dynamics (SEED), Pukyong National University, Busan 48547, Korea)
• Nam-Hoon Kim(Dohwa Engineering Co., Seoul 06178, Korea)
• Samgyu Park(Korea Institute of Geoscience and Mineral Resources, Daejeon 34132, Korea)
• Jae-Yeol Cheong(LILW Strategic Team, Korea Radioactive Waste Agency, Gyeongju 38062, Korea)
• Se-Yeong Hamm(Department of Geological Sciences, Pusan National University, Busan 46241, Korea, Geoscience Co., Busan 48058, Korea) Corresponding author