ABSTRACT:

This research was aimed to determine the level of some selected heavy metals, physical and chemical parameters of the soil samples in some selected automobile workshop. Soil samples were collected at two depths (0-15 and 15-30cm) from 10 Automobile workshop dumpsites within the Gwagwalada Area Council and a control sample. The soil samples were collected with the aid of a soil auger. The soil samples were were taken to the laboratory where they were analyzed for some physical and chemical properties as well as some heavy metals in the soil.also, microbial analysis was carried out on the soils. Data collected was subjected to 2 way Analysis of Variance (ANOVA), mean values were separated using Least Significant Difference (LSD). Results of the analysis of soil samples revealed that the samples are contaminated with Arsenic, Cadmium, lead and Copper with concentrations levels (mg/kg) ranged between 6.10 – 11.80, 14.20±0.10 – 21.30±0.10, 121.87±2.97 – 230.00 ±1.00, 241.67 ±10.4 – 437.22 ±0.10 respectively for surface soil (0-15cm) while the concentration range for subsurface soil (15-30cm) were 5.60-8.84, 12.93 ±0.67 – 23.90 ±0.5.28, 150.50 ±0.10 – 227.68±0.02, 311.67 ±10.4 – 437.22 ±0.01 respectively when compared with the standard permissible limit by FAO/WHO, 2001, FEPA, 1991 and NESREA, 2001. Zinc concentration for both surface and subsurface soil were below the permissible limit as set by (NESREA, 2001) with a range (mg/kg) concentration of 250.00±10 – 339.90±0.01 and 210.00 ±0.10 – 333.80±0.01 for surface and subsurface soil respectively. The bacterial species isolated were, Corynebacterium Spp, Pseudomonas aeruginosa, Bacillus megaterium, Bacillus subtilis, Streptococcus Spp, Bacillus cereus, and Staphylococcus aureus while the fungal species isolated were Aspergillus niger, Alternaria Spp, Curvularia spp and Penicillium chrysogenum. It was observed that these auto mechanic workshops do have a negative (pollution) impact on the surrounding environment, which calls for stricter regulation on their location within cities and how waste issuing from these clusters is disposed of. However, it can be concluded that the results obtained from this study showed that, there are variation in the metal contents in the soil from one location to the other. The result of this study indicates that indigenously it is possible to isolate bacterial and fungal micro flora capable of degrading complex hydrocarbon compounds. This investigation provides information that would lead to selection of bacterial and fungal species that could be employed for bioremediation in environments polluted with used engine oil.