Petroleum Contaminants from Spilled Soils in Niger Delta under Tropical Weather Conditions Studied with Validated and Traceable Methodology

Petroleum contamination of soil from the Niger Delta was investigated after an extensive oil spillage. Contamination of soil spilled with the crude Oil was investigated about few weeks after the spillage from the Shell Petroleum marginal well head. 50 Soil soil samples (300-500 g) were collected at several points in the South-South Niger Delta. Control samples were taken from four unaffected sites within the vicinity of spillage with similar soil characteristics. Samples and controls were collected at depths of 0-15 cm, 15-30 cm and 30-60 cm respectively.

The soil samples were prepared for analysis using solvent extraction methods, passed through column of Florisil® and sodium sulphate to remove moisture, gross impurities and to aid in column performance. Samples were analysed by gas chromatography fitted with a flame ionisation detector under developed and optimised methods.

Soil samples and controls were collected at depths of 0 - 15 cm, 15 - 30 cm and 30 - 60 cm. The levels of penetration and migration of the hydrocarbons C10-C26 and C26-C34 through the soil layers were assessed by cluster analysis to determine the spatial distribution, penetration and similarity of these compounds over the contaminated area. The results obtained also showed elevated levels of hydrocarbon contamination when compared with the reference sites. Proper and regular monitoring of Crude Oil Well-heads, drastic and suitable remediation processes were recommended to the Government and the respective Oil exploring Companies.