Postmonsoon groundwater quality of Keonjhar urban area, India for drinking and domestic use

This study evaluates the post-monsoon groundwater quality of Keonjhar urban area, Odisha, a region famous for rich mineral resources, significantly influenced by mining activities. A total of sixty-six groundwater samples were collected during 2022 and analysed for major physico-chemical parameters following standard methods. The results indicate that groundwater is slightly acidic to moderately alkaline (pH: 6.2–8.3) and predominantly falls under hard to very hard categories. Hydrochemical facies analysis using Piper trilinear diagram reveals dominance of Ca–Mg–HCO3 type, followed by Ca–Mg–Cl–SO4 type. Comparison with BIS (2012) drinking water standards shows that most parameters are within permissible limits, except iron and fluoride,which exceed limits in several locations. Approximately 32% of samples show fluoride concentrations above 1.5 mg/l, while more than half of the analyzed samples exceed permissible iron limits. The study highlights that groundwater is generally suitable for domestic use with appropriate treatment; however, fluoride and iron contamination pose significant challenges for safe drinking water. Regular monitoring and targeted mitigation strategies are recommended.