ANALISIS POTENSI RESAPAN DAN KUALITAS AIR SISTEM KARST TELAGA BLEMBENG DAN GOA BANTENG, PADA SISTEM KARST GOMBONG SELATANNIM.: 22106020014Fathir Yusron KhoirauthorThe Southern Gombong Karst in Kebumen Regency is an active karst area characterized by a complex hydrogeological system formed through the dissolution of carbonate rocks and the interconnection of subsurface flow. This study aims to analyze the potential groundwater recharge zones in the Telaga Blembeng and Goa Banteng areas using the APLIS method and to assess water quality based on physical and chemical parameters (electrical conductivity, total dissolved solids, pH, and Ca²⁺) to understand their relationship with recharge activity and subsurface conditions. Spatial analysis was conducted using altitude, slope, lithology, land cover, and soil data within a geographic information system to produce a recharge potential map. The results show that the recharge potential in the Southern Gombong Karst area is divided into two classes, medium and high, with Telaga Blembeng categorized as a high recharge zone and Goa Banteng as a medium recharge zone. Water quality analysis indicated values of 304 μS/cm for electrical conductivity, 152 mg/L for TDS, pH 7.4, and 48.46 mg/L for Ca²⁺ at Telaga Blembeng, while Goa Banteng showed 386 μS/cm, 193 mg/L, pH 7.7, and 64.76 mg/L, respectively. Higher Ca²⁺, TDS, and electrical conductivity values at Goa Banteng indicate greater mineralization due to longer water–rock interaction in the subsurface. Based on these findings, Telaga Blembeng functions as a recharge area, while Goa Banteng serves as a discharge area within the same karst aquifer system. The results of this study can serve as a basis for sustainable groundwater resource management in the Southern Gombong Karst region.530 Fisika2026-01-22UIN SUNAN KALIJAGA YOGYAKARTA;FAKULTAS SAINS DAN TEKNOLOGIThesis