Analysis of Groundwater Quality and Determination of its Main Chemical Factors in the Kowsar Aquifer Management Station

Abstract

Groundwater samples were prepared from 20 wells in the Gareh Bygone aquifer during the 2018 to 2020 years seasonally. Chemical characteristics of these samples including EC, pH, TDS, TH, SAR, SO4-2, Cl-, Na+, K+, Mg+2, Ca2+ and HCO3- were analyzed. The average of water salinity was 4.7dS/m, the acidity was 7.5, the average SAR value is about 6.7 and in some wells, this factor is about 10.6. Analysis of variance shows that all chemical characteristics except HCO3- have a significant difference. The principal component analysis identifies TDS, SO4-2, HCO3- and Na as the most effective variables in reflecting groundwater quality. Factor analysis also shows high TH, Na+, and HCO3-. Aquifer water resources are divided into three separate groups. The first group (with 97% similarity) receives the most impact from floodwater spreading and artificial recharge, and the other two groups (with 93 and 70% similarity) are located in the marginal areas or outside the floodwater spreading system. Despite poor management and uncontrolled discharge of the aquifer, at least in the central parts of the aquifer, which are more affected by artificial recharge by floodwater spreading, groundwater quality is more desirable.

Keywords

• aquifer
• chemical analysis
• electrical conductivity
• garehbygone