Groundwater Quality Evaluation Based on Geochemistry Analysis in Wates Area, Blitar Regency, East Java, Indonesia

Abstract

Groundwater is the primary water resource for communities in the Wates area, Blitar Regency, East Java. This study aims to evaluate groundwater quality based on physical and geochemical characteristics and to assess its suitability for domestic use. The study area is underlain by limestone-dominated lithology with high calcium carbonate (CaCO₃) content, which strongly influences groundwater chemistry. Groundwater samples were collected from three locations—Tugurejo, Sumberoto, and Sukorejo—representing wells and springs. Physical parameters (color, odor, and taste) and geochemical parameters (pH, total dissolved solids (TDS), Fe, Mn, Cl⁻, CaCO₃, and SO₄²⁻) were analyzed and compared with Indonesian clean water quality standards (Regulation of the Ministry of Health No. 416/MENKES/PER/IX/1990). The results indicate that groundwater quality in the study area is generally acceptable for clean water use, although elevated manganese concentration was detected at one sampling location. Overall, groundwater chemistry is primarily controlled by limestone dissolution and water–rock interaction processes.