Abstract

 The study deteimined (he optimum conditions of crude oil soil treated with vermicast to remove polycyclic aromatic hydrocarbon (PAH) and investigate the effect of adsorbent dosage on total petroleum hydrocarbon (I PH). Physicochemical parameters such as pH, total organic carbon, sulfate, nitrate, phosphate, sodium, potassium, calcium and magnesium using standard procedures, lotal petroleum hydrocarbon (TPH) was determined using atomic absorption spectrophotometer (AAS). Soil sample was collected from Michael Okpara University of Agriculture Umudike, Umuahia, Abia Sate (MOLAU FARM). The portion of land was cleared of the vegetation cover, dug with a shovel and collected into tw o buckets. One ofthe samples was contaminated with crude oil and the second sample left uncontaminated. In this study, vermicast was used to clean up crude oil contaminated soil after allowed it for several days in other to remove the petroleum hydrocarbon, determine the physico-chemical properties and restore the soil to its natural position. The analysis was done in Agricultural. Civil and Chemical Engineering Laboratory in College of Engineering and Engineering Technology Michael Okpara University of Agriculture Umudike, Umuahia. Abia Sate. The Physico-chemical properties and Heavy metal analysis was done at Nation Soil Plant and Waler Laboratory Umuoha-Azueke K.M5 Umuahia Ikot-Ekpene Road opp Industrial.T imber Market Umuahia, Abia State. At the end of the study, it was discovered that Earthworm bioremediation does not only remove the contaminant but also enrich the soil by the addition of vermicast after reworking of the contaminated soil in the gut ofthe earthworm. These findings suggest that the earthworm could be applied in the later stages of bioremediation, even in highly contaminated soil with crude oil when the toxicity of the contaminant may have decreased or pre-treated to a tolerable level.