Heavy metal contamination, major ion chemistry and appraisal of the groundwater status in coastal aquifer, Kalpakkam, Tamil Nadu, India

摘要: Abstract A total of 228 groundwater samples were collected at a depth 10–30 feet below ground level (bgl) during one year period from nineteen wells around Kalpakkam, Tamil Nadu, India which is known for nuclear installations. The studied aquifer mainly constitutes sand and weathered charnockite with thickness varying 3 to 12 m unconfined nature. Physical parameters, major ions, heavy metals compared guideline values water quality index. order dominance cations anions were; Na + >Ca +2 >Mg >K HCO − >Cl >NO >SO 4 −2 >PO −3 >Br >F . Four types (Ca-HCO , Na-Cl, mixed Ca-Na-HCO Ca-Mg-Cl) observed. Alkali (Na +K ) exceeded the alkaline earth (Ca +Mg weak acid (HCO3 strong (Cl +SO ). was Zn>Fe>Mn>Ni>Cu. Bureau Indian Standards compliance dissolved solids (26–27%), alkalinity (35–44%), hardness (24–27%) nitrate (41–43%) indicated that most acceptable limit drinking water. High an average 104.5 mg/l (82% BIS limit) observed in central part study area (between Kalpakkam township site) ascribed influence domestic sewage septic tank effluents. Observed low fluoride this (avg. 0.1 mg/l) contradicted earlier report high location. Based on Canadian Council Ministers Environment Water Quality Index (CCME WQI), classified as marginal excellent class majority falling under fair category. Except 4–5 categorized marginal, other suitable drinking. formed spatial distinct groups based ranking. present provides comprehensive status terms its suitability human consumption.