Groundwater quality evaluation using Water Quality Index and GIS technique for the Holocene and Pleistocene aquifers in the coastal zone of Ninh Thuan province

This study represents the application of Water Quality Indices (WQI) and GIS techniques to grading water pollution factors that influenced groundwater quality Holocene (qh) Pleistocene (qp) aquifers in coastal zone Ninh Thuan province. 100 underground samples were collected from residential well qh aquifer (53 samples) qp (47 samples). indices using incorporated total dissolved solids (TDS), chloride (Cl-), flouride (F-), nitrite (NO2-), nitrate (NO3-), iron (Fe3+), manganese (Mn2+). Calculated WQI scale for ranged very good inedible drinking purpose. The result shown sample graded as “excellent quality” accounted most (23,3% 14,9% aquifer, respectively), followings “good grade ranked second (9,4% 8,5%); “poor (43,4% 30,04%); “very poor (1,89% 10,64%); “inedible” (16,98% 31,9%). poor” mostly distributed on southeast Hai district Tri commune (Ninh district), Xuan Cong communes (Thuan Bac Phuoc district) south area because exceptionally high TDS. Other which low TDS but “bad” due surprisingly concentrations other ions (Cl-, NO3-, NO2-). provided concreted information polluted agents a valuable tool support authorities management zoning area.