Describing the Role of Aerobic Microorganisms in the Biodegradation of Petroleum Hydrocarbons Laboratory Contaminated Groundwater

Abstract

This study described the role of aerobic microorganisms in the biodegradation of petroleum hydrocarbon contaminated groundwater. Groundwater sample treated with nutrients were compared with untreated water sample. The total hydrocarbon content removal in the water treated with nutrients and untreated water sample (natural attenuation) at day 56 showed percentage removal of 89 and 74, respectively. Total heterotrophic and total hydrocarbon utilizing bacterial count increased progressively in all experimental samples. Bacterial strains isolated include Bacillus sp., Arthrobacter sp., Micrococcus sp., Pseudomonas sp., Alcaligenes sp. and Flavobacterium sp. The total petroleum hydrocarbon reduced from 15.33955 mg/L to 3.90361 mg/L and 9.49634 mg/L, in water sample treated with nutrient and untreaed water sample, respectively at the end of day 56. The physicochemical analyses at day 56 were within the World Health Organization standard for drinking water. Total petroleum hydrocarbons in laboratory contaminated groundwater were utilized by the aerobic microorganisms present in the water samples, however, treatment with nutrient showed greater removal of the hydrocarbon pollutants.