Groundwater quality trend analysis and zoning using TFPW-MK and GIS (Case Study: Najaf Abad Aquifer)

Investigating the quality and contamination of groundwater resources in the planning and development of water resources is very important and necessary. The purpose of this study is to map the quality of water, pollution, and study the trend of changes in quality parameters in the long run in Najafabad aquifer. For this purpose, the parameters EC, TDS, SAR, pH, TH, Cl, CO3, Ca, Mg, Na, K, HCO3, NO3 and heavy elements including zinc, copper, lead, cadmium and arsenic were investigated from laboratory samples. . The agricultural water quality classification according to the Wilcox diagram is mainly in the range of C3-S1 and in the drinking water according to the Schuler diagram it is mainly acceptable and intermediate and in some cases inappropriate. The amount of heavy elements is allowed. The trend of changes in qualitative parameters was evaluated using MK and TFPW-MK methods and the results showed that water quality decreased over time. Some qualitative parameters were mapped in ArcGIS environment. The average nitrate concentration was calculated to be 63.13 mg / L and the maximum nitrate concentration in the northern and central parts of the aquifer was 193 mg / L. Regarding the results of this study, continuous monitoring and quantitative and qualitative investigations of groundwater resources and necessary measures to control pollution in the Najafabad aquifer area is very necessary.