Investigation and Mapping of Chemical Quality of Drinking and Agricultural Water Wells in Some Cities of Isfahan Province, Iran

In recent years, population growth, lack of rainfall, and increase in urban, industrial, and agricultural activities have caused more use of underground water resources. This will cause many problems for the economy, ecosystem, and human health. Considering the need to investigate and monitor the quality of groundwater, the present research was carried out with the aim of investigating the important chemical parameters of water wells in some cities of Isfahan Province, Iran.

To conduct this research, 181 well water samples were collected from Khansar, Daran, Tiran, Fereydunshahr, Najaf Abad, and Dehaghan cities in Isfahan Province. Then, electrical conductivity (EC), pH, and nitrate concentration were measured. Next, nitrate hazard quotient (HQ) (non-carcinogenic risk of nitrate) was calculated. ArcGIS software was used for mapping the measured features.

The amount of EC, pH, and nitrate varied from 191.4 to 7624 μS/cm, 6.49 to 8.20, and 1.9 to 99.2 mg/l, respectively. The lowest value of HQ (0.03) was calculated for the group of men and the highest value (3.68) was obtained for the group of children. The average value of HQ for men, women, and children was 0.61, 0.74, and 1.40, respectively.

All measured pH values were below the national standard of Iran (1053) and the Environmental Protection Organization of Iran. The studied areas had no limit in terms of nitrate concentration for using well water for agriculture. However, in 78.6% of the study areas where the amount of nitrate was in the range of 22.1-50 mg/l, there is a possibility of increasing nitrate concentration and making it unsuitable for drinking.