Hydrogeochemical assessment and suitability evaluation of groundwater in a hard rock region: A case study of Jambuduraikottai, Tamil Nadu

Groundwater is primarily used for drinking and irrigation in hard rock regions like Jambuduraikottai, Tamil Nadu. This study aimed to evaluate the suitability of groundwater sampled from the region for drinking and irrigation purposes. Twenty groundwater samples were collected, analyzed, and mapped using interpolation methods. Total hardness (TH), K+, Cl–, and F– exceed the not permissible limits in various locations. Piper and Gibbs plots indicated that water type is Ca2+-Mg2+-Cl–, which reveals rock dominance as a major factor affecting groundwater chemistry. Wilcox plot indicates that the majority of samples were suitable for irrigation purposes. The groundwater quality index showed that 90% of the samples are drinkable. Moreover, irrigation indices such the Kelly ratio and Sodium adsorption ratio indicate suitability for irrigation, whereas the Na% causes notable risk in 10% of the locations. Thus, proper measures such as regular monitoring and controlled usage of fertilizers must be taken to prevent further contamination and also for long-term usage.