Transport Modeling of Ground water Nitrate Contaminant in Hamedan Drinking Water Wells Area

Hamedan-Bahar plain is influenced by contamination agents such as Hamedan and Bahar sewage treatment, Hamedan industrial shambles, henneries and heavy agricultural activity. To provide the useful data for simulation of contamination transport in the study area, 23 wells were sampled during two periods. Ground water flow and nitrate transport were simulated using MODFLOW and MT3D codes. This study indicates that Yeknabad area have a Maximum nitrate concentration that rises due to agricultural fertilizer and strengthening by fine grain sediment (silt and clay). Nitrate transport from surface to groundwater is increased by low thickness of alluvium in Hamedan industrial shamble and southern study areas. High thickness of alluvial sdiments and sanitary area in Hamedan drinking water wells, decrease the groundwater contamination. Also the quality of groundwater in Bahar third dam and Ghorogh Bahar areas, in despite of contaminant agent, improve.