Investigation of temporal and local variations of heavy metal (pollutant and nutritional) concentration and qualitative parameters in wastewater of refinery used in irrigation of Shahin Shahr green space of Isfahan

The purpose of the present study was to monitor the effluent of municipal wastewater treatment plant used in Shahinshahr lands to investigate the heavy metal concentration and quality parameters based on environmental standards in wastewater during 1396-97. In this study, samples from seven stations were collected during one year. The samples were subjected to standard concentrations of heavy metals such as lead, nickel, cobalt, chromium and nutritional heavy metals zinc, copper, iron and manganese, and acidity, electrical conductivity and total solids content. The results were statistically analyzed in two ways: measuring seasonal or monthly (temporal) and stationary (spatial) changes. The results showed that the concentration of heavy metals in the wastewater was lower than the permissible limit. Comparison of the concentration of each heavy element with the standards of Iran Environmental Protection Agency, World Health Organization and Environmental Protection Agency showed that according to the relevant standards, the treated wastewater after chlorination is capable of irrigation for green space. There was no limitation on the acidity and total amount of suspended solids. Electrical conductivity was exceeded during the monitoring period and by standards the effluent had average electrical conductivity for irrigation.