Analysis of Heavy Metal Concentration of Surface Water Around Gas-flaring Stations in Selected Areas of Delta State, Nigeria

Gas flaring is a widespread practice in the Niger Delta region, resulting in the release of toxic gases and heavy metals particulate into the atmosphere. This research investigated the heavy metal concentration in surface water around gas flaring stations in selected areas of Delta state. Locations A, B, C representing Amukpe, Ekpan, Oton where gas flaring activities are still ongoing were selected for this study, while Location D(pontu) is about 6km from the closest gas flare was used as control. Water samples were collected from rivers/streams of study locations at radial distance of 100m from flare points for the analysis. The results showed that copper(Cu) with values ranging from 0.06-0.09mg/L and Zinc(Zn) with values ranging from 0.49-0.62 had higher values at sites A, B, and C compared to control site D . Locations B and C showed the highest copper (Cu) concentrations , Location B had the highest Iron (Fe) concentration while Location A had the highest Zinc concentration when compared with other sample locations. The Physicochemical properties and anion analysis also followed similar pattern with the gas flare impacted location having higher values in some parameters when compared with the control. The levels of heavy metals determined in this study, though were significantly higher (p < 0.05) in gas flaring locations compared to control but were not above the world health organization (WHO) and Nigeria Environmental Standard Regulation Agency (NESREA) standards for drinking water. The results obtained represent a gradual increase in the concentration of heavy metals in the immediate environment of the gas flare impacted water body. It is necessary to monitor water quality parameters including heavy metal concentration in aquatic environments continuously and appropriate measures should be put in place by government and petroleum companies to maintain standards.