Assessment Of Variation In The Concentration Of Heavy Metals In Groundwater Within Oil Producing Community Ogba/Egbema/Ndoni L.G.A. Rivers State

ABSTRACT

Groundwater constitutes a major source of potable water supply foragricultural, industrial and domestic applications. This has led to the increase in the demand for ground water exploitation. Borehole water being an ideal source of portable water supply has been employed to meet this teeming demand. For the purpose of this research, borehole water was adopted as a sample model for the experiment to determine the extent of heavy metal contamination in the ground water of the study area. Six borehole water samples were collected from each of the oil exploration and exploitation communities of Ogba/Egbema/Ndoni Local Government Area of Rivers State namely Obirkom, Obite, Obiebe, Ogbogu, Obagi, Obigwe (control) and were taken to the laboratory. Eight heavy metals were sampled and results were obtained. The heavy metals are lead (Pb) iron (Fe) Arsenic (Ar) Nickel (ni), and Cadmium (cd) Chromium (Cr) Vanadium (V) and Manganese (Mn). Others are phosphate (PO3-4), Phosphate (Pi), Phosphate (P2O3), calcium hardness (CaCO3). The result shows the absence of lead in locations 3 & 2. Iron was highest in location 2 and was lowest in location 5. Asenic (As) was significantly present in high values in all the locations except in location 2 with value of 0.05 mg/l. nickel was above the WHO limit of 0.05mg/l in location 1 & 2 and was not detected in the rest of the locations. The value of cadmium (Cd) was high in all the locations. Chromium was detected in high value in all the location except in location 5. Manganese is negligible in all the locations. Likewise, the physicochemical parameters investigated are pH, temperature turbidity, conductivity, oil and grease, total dissolved solid and total hydrocarbon were also sample. Their values were also compared with the World Health Organization Standard and it shows that there was normal Temperature values in all the locations at the time of this experiment. The turbidity , values were high in all the locations except location 2. The value of the conductivity was very high in location 1 and high in location 2 but normal in location 3 & 6. Oil and grease was not indicated in location 2 and it was high in location 1, 3, 4 & 5. The value of total dissolved solid and total hydrocarbon was very high in all the location. From the analysis of the result obtained, it can be accepted that the presence of heavy metals in the groundwater of the study area can be attributed mainly to the activities of the oil companies prevalent in that area.