Abstract:
Present study was conducted to analyse the physio-chemical parameters of produced water (PW) of Dakhni oil field, Attock, Punjab, Pakistan and their impacts on surrounding soils. PW samples were collected from various locations including source points, ponds and outlet points. Soil samples were collected from study area from various points at various distances about 0-15 cm depth to analyse the impacts of PW on surrounding soils. Some of the parameters were analysed on the spots and rest were analysed in the Laboratory by using standard methods. The results of physical parameters i.e. pH, TDS and Conductivity, were ranged from 5.5-7.5; 2620-826000 mg/L and 3.8-120μs/cm respectively. As per Pak-EPA standards pH of PW lies within the defined limits and TDS is much higher than the limit. Results of ions analysis in PW samples indicate that levels of, , , , F¯, Cl¯ ranged from 802- 1452; 9.6-710; 396-6544; 123-654; 1-3.3 and 6368.23-31831.19 mg/L respectively. F¯ is within permissible limit while Cl¯ values are much higher than Pak-EPA. Heavy metal results showed that Zn, Cu, Fe, Mn, Cr, Pb, Ni and As ranged from; 2.2-3.2; 1.1- 2.2; 1.8-2.44; 1.12-3.66; 1.3-1.8; 0.6-1.8; 1.05-1.27 and 0-0.5 mg/L respectively, which indicate that As and Zn were within the permissible limit while all other heavy metals were above the permissible limit. Results of soil samples showed that most of the parameters that are above the permissible limit in PW also showed high concentration in soil, which indicate the pollution in surrounding soil due to discharge of produced water. From the present study, it is concluded that PW showed highly contamination of pollutants so it should be treated before releasing into the surrounding environment in order avoid the impacts.
