Petroleum Hydrocarbon Occurrence in Groundwater along the Trans-Niger Pipeline in Ogoniland, Rivers State, Nigeria

Abstract

The Trans Niger Pipeline (TNP) commissioned in 1965 traverses Ogonil and along three (3) main corridors, covering a total distance of 62km and evacuates about 150 thousand barrels of crude oil per day to the Bonny oil Terminal. There have been several episodes of oil spillages along the TNP caused by pipeline failures and third-party interdiction; of which 84 oil spill incidents were reported between 2012 and 2014 alone, spilling a total volume of about 17,957bbls of crude oil into the environment. The incessant spilling of petroleum hydrocarbons along the pipeline Right-of-Way has polluted groundwater within these corridors and adjoining communities. This paper highlights the occurrence petroleum hydrocarbon contaminants and heavy metal complexes in groundwater within the corridors of TNP Right-of-Ways. Groundwater samples were obtained from 133 Geo-referenced boreholes and water wells within 200m swath of the TNP in Ogoniland. The results of laboratory analyses reveal the presence of Polycyclic Aromatic Hydrocarbons (PAHs) in concentrations ranging from 0.06µg/l to 1.0μg/l, Total Petroleum Hydrocarbons (TPH) ranged from 1.39μg/l to 4.34μg/l; in groundwater. Furthermore, the following heavy metals: Barium, Chromium, Cobalt, Cadmium, Lead and Nickel were also found in concentrations ranging from 0.11 µg/l to 19.5 µg/l. Hence, the concentrations of the aforementioned pollutants in groundwater along the TNP heightens our concerns for the safety of the inhabitants of communities who rely on water wells contiguous to the TNP for their everyday use. Chronic exposures to these toxins will ultimately have deleterious health effects especially for children.