Evaluation of the Bacteriological Diversity and the Physicochemical Properties of Kolo-Creek Oil Field Wastewater

Abstract

Evaluation of bacteriological diversity and physicochemical parameters as well as the heavy metals present in the water samples collected from Kolo creek flow station located in Bayelsa State in the Niger Delta, Nigeria was carried out for the period of eight months (March to October). Oilfield wastewater samples were obtained in four different locations of the Kolo creek in sterile bottles and were transported to the Microbiology Laboratory of the Rivers State University for analysis.10-fold serial dilutions were carried out and aliquots of 0.1 ml were inoculated and spread plated unto sterile nutrient agar, MacConkey agar and mineral salt agar plates. The water samples were analyzed for the total heterotrophic bacteria, coliform bacteria and hydrocarbon utilizing bacteria. The total heterotrophic and coliform bacteria load in log10CFU/ml ranged from 6.25 to 13.62 and 4.04 to 5.75 respectively, while the hydrocarbon utilizing bacteria ranged from 0 to 4.81. Higher Mean monthly counts of the total heterotrophic bacteria, coliform bacteria and hydrocarbon utilizing bacteria were 13.48 in March, 5.44 in April and 4.51 log10 CFU/ml in March, respectively. While lower mean monthly counts recorded were 6.72 in August, 4.29 in August and 0 log10CFU/ml in April, respectively. Fifteen bacteria belonging to Micrococcus, Chromobacterium, Listeria, Actinomyces, Staphylococcus, Bacillus, Enterobacter, Serratia, Escherichia coli, Vibrio cholera, Vibrio parahaemolyticus, Proteus, Shigella, Pseudomonas and Acinetobacter species were identified. While Bacillus, Pseudomonas, Serratia, Micrococcus, Proteus, and Acinetobacter species were the hydrocarbon utilizing bacteria identified. The bacteria populations varied across the months. The physicochemical parameters as well as the heavy metals were within the permissible limits set by regulatory bodies. The hydrocarbon utilizing bacteria in this study could be used for bioremediation study.