Use of GIS in Hydrogeochemical Study and Quality Status From Pudukkottai District, Tamil Nadu, India

Abstract

This study focused on hydrogeochemical characterisation and groundwater quality deterioration based on drinking, irrigation purposes in Pudukottai district. Eighty-seven groundwater samples were collected from the bore and dug wells during pre and post monsoon seasons in the year 2019. The order of mean abundance of ions is followed as C l > HCO3 > Na > SO4 > Mg > Ca > K (325.5 > 182.2 > 181.4 > 83.2 > 51.1 > 35.8> 9.1 > 8.6 > o.9 > 0.3) and Cl > Na > HCO3 > SO4 > Mg > Ca > K (415.7 > 230.3 > 198.2 > 82.9 > 53.8 > 43.4 > 14.9) in both seasons. Analytical results are used in Piper, Gibbs, Na% vs. EC, USSL, and PI to evaluate the hydrogeochemical processes. Rock water interaction and evaporation processes causing variations in hydrogeochemistry of the study area during pre and postmonsoon. Nearly 15 % of the groundwater samples were not permissible for drinking based on the standard, which is distributed in south eastern region of the study area. It is revealed from Na%, SAR, RSC, MgC and KR results that majority of the groundwater samples are fit for irrigation uses. The higher concentration of EC, TDS, Cl and Na values noted in south region due to the sea water intrusion that attributed by excess pumping in the coastal regions. The drinking water quality index (DWQI) and irrigation water quality index (IRWQI) are calculated to identify the suitability of groundwater for drinking and irrigation purposes. However, this research concludes that the groundwater quality of maximum part in the district is appropriate for drinking as well as agriculture which can be used for the sustainable growth. It is also recommended implementing the artificial recharge techniques to improve the groundwater quality.