Majang Irene Mokgadi
Department of Life Sciences, Faculty of Health and Environmental Sciences, Central University of Technology, Free State, Bloemfontein 9301, South Africa
Saheed Adeyinka Oke
Department of Civil Engineering, Centre for Sustainable Smart Cities, Faculty of Engineering Built Environment and Information Technology, Central University of Technology, Free State, Bloemfontein 9301, South Africa
Leana Esterhuizen
Department of Life Sciences, Faculty of Health and Environmental Sciences, Central University of Technology, Free State, Bloemfontein 9301, South Africa
Innocent Mugudamani
Department of Civil Engineering, Centre for Sustainable Smart Cities, Faculty of Engineering Built Environment and Information Technology, Central University of Technology, Free State, Bloemfontein 9301, South Africa
Groundwater is critical for supplying drinking water to billions of people worldwide. However, their excessive permeability makes them more vulnerable to retaining and spreading contamination. Assessing groundwater vulnerability is crucial for sustainable management, as it aids in reducing the risks associated with contamination of this valuable resource. As a result, the primary aim of this paper is to critically review and synthesize recent advances in groundwater vulnerability and risk assessment using hydrogeochemical parameters. A summary of groundwater contamination, sources, and consequences is presented. Information on hydrogeochemical factors and groundwater vulnerability is summarised. A review of the most commonly used groundwater vulnerability assessment methods is covered. It also covers the assessment of groundwater vulnerability using hydrogeochemical parameters and statistical approaches. Furthermore, these approaches are supported by global case studies. Finally, the limitations, conclusion, and future recommendations are presented. It can be concluded that integrating hydrogeochemical parameters with groundwater vulnerability models is an effective method for assessing the risk of groundwater contamination and developing management plans. Researchers in the fields of health, earth sciences, environmental studies, and water sciences will find this comprehensive review to be a valuable reference, as it offers an in-depth understanding of the current knowledge on the integration of hydrogeochemical parameters in groundwater vulnerability and risk assessment studies.
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