Investigation of Arsenic Anomalies and Its Probable Origins in Maragheh Plain

The objective of this study is evaluating hydrochemical properties of groundwater in Maragheh area, including: Cations, Anions, Total Dissolved Solids, Electrical Conductivity, pH and Heavy metals (As, Fe, Mn) and investigating the statistical relations between these parameters and Probable Origins of contamination.

In order to carry out ground water quality monitoring, and evaluate the controlling processes and to determine cations and anions sources of the groundwater, 34 wells were selected for sampling from July 2014 and April 2015and water quality parameters were measured and sent to the Laboratory Applied Research Center of Geological Survey & Mineral Explorations of Iran (Elburz).  Data analysis was performed through SPSS software and Factor Analysis & Pearson correlation coefficient test.

The chemical composition of the surface and groundwater is controlled by several processes such as mineral dissolution, increasing evaporation from the aquifer, irrigation return flow, saline water intrusion in the Ajbashir Plain, geological status of the area, anthropogenic inputs.

The concentration of arsenic based on WHO standard is 10μg/L, while the maximum arsenic concentration in the study area is 308.5μg/L and the mean concentration is 44μg/L. According to the results, it relies that arsenic probable sources can be concerned to industrial waste water in Maragheh and Bonab industrial complex, agricultural activities (using pesticides and insecticides) and geological factors (existence of Shemshak formation), rocks and sediments derived from the erosion of these rocks and coal mines (Khormazard).