Hydrochemical Characteristics of Groundwater in Noyyil River Basin, Tamil Nadu, India

摘要

Groundwater is the major source for domestic, agricultural and other related activities. An attempt has been made to study the hydrogeochemistry characterization of Noyyil river basin. The seasonal variation of the chemical budget of ions was determined from the hydrogeochemical investigation of the groundwater. Though, the effect of monsoon does not change the order of abundance of cations, it does change the concentration of various ions, and it is found that there was a considerable change in case of all major ions. Broadly speaking, the groundwater has a chemical composition within the permissible limits suggested for drinking water. Nitrates is higher than the acceptable limits in some samples, that is mainly due to the usage of fertilizers. Hydrogeochemistry of groundwater of Noyyil river basin, which is predominantly a hard rock terrain, has been studied to evaluate the quality of groundwater for domestic and agricultural purposes. Groundwater samples from sixty locations were collected both during January 2007 and January 2008 in and around Noyyil river basin and analysed for their major cations and anions. Physical and chemical parameters of groundwater such as EC, TDS and ionic concentrations of Na~+, K~+, Ca~(2+), Mg~(2+), Cr~-, HCO_3~-, CO_3~(2-), SO_4~(2-), NO_3~- and F~- have been determined. Based on the analytical data hydrohemical indices like Na%, SAR, RSC and PI have been calculated. The ionic concentration of TDS, Na, K, SO_4~(2-), NO_3~- and EC in the sampled locations vary spatially and temporajly and the same is attributed for severe contaminations. Salinity, SAR, Na% indicate that the majority of the samples are not suitable for domestic and irrigational purposes and far from drinking water standards as prescribed by WHO.