Groundwater quality assessment for domestic, irrigation and industrial purposes in the Chalk Hills, Salem District, Tamil Nadu

Water is a basic necessity for all living things and is essential to human life. Groundwater is a major resource for domestic, irrigation, and industrial purposes. The goal of the current investigation was to determine whether groundwater in the Chalk Hills, Salem, was suitable for domestic irrigation and industrial purposes. It is expected that the ongoing mineral extraction in the study area impacts the quality of groundwater. A study has been carried out to determine whether mining and industrial operations are contaminating groundwater and causing variations in quality. We have taken twenty groundwater samples in the Salem Chalk Hills. The primary physical and chemical parameters like potential Hydrogen (pH), total dissolved solids (TDS), total hardness (TH), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), bicarbonate (HCO3), carbonate (CO3), chloride (Cl), sulphate (SO4), nitrate (NO3), and fluoride (F) were analyzed for DWQI (Drinking Water Quality Index) and compared to the BIS and WHO standards. The secondary parameters of irrigation groundwater quality indices, such as sodium adsorption ratio (SAR), sodium soluble percentage (SSP), residual sodium carbonate (RSC), permeability index (PI), corrosivity ratio (CR), magnesium adsorption ratio (MAR), and Kelly's Ratio (KR), were also derived from the primary parameter for IWQI. The DWQI was classified into excellent to unfit condition of groundwater quality based on their Water Quality Index (WQI). The spatial distribution of DWQI pre-monsoon (35%) and post-monsoon (32%) indicates that there is a slightly unsustainable to sustainable state of groundwater quality. The electrical conductivity, sodium adsorption ratio, sodium percentage, permeability index, Wilcox, and United States Salinity Laboratory diagrams were taken into consideration when determining whether water was suitable for irrigation use. Based on sodium percentage, the water samples were classified as good (75%) and permissible (25%). This indicates the study area's water is suitable for irrigation purposes. Furthermore, Sodium Adsorption Ratio (SAR) analysis reveals that 100% of the water samples are safe for irrigation. Residual sodium carbonate (RSC) analysis shows 95% of the samples are safe, with only 5% falling under the doubtful category. The water chemistry of the research area meets the requirements for drinking water, agricultural activities, and industrial applications, based on evaluated water quality parameters.