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Assessment and Remediation of Contaminated Lands by Crude Oil using Enhanced Natural Attenuation

Ubaezue Egereonu, C E Ezekiel, K C Enenebeaku, N J Okoro, BN C Nlemchukwu, J C Egereonu, M C Igbomezie, I C Obiagwu, M O Ezekoye, D E Ndukwu


This study evaluated the effect of remediation by enhanced natural attenuation, (RENA) carried out to determine the effectiveness of RENA as a method of remediation in restoring crude oil-contaminated land. The work compared its effect on two different spills of different intensities and the effects across different depths of penetration. It further investigated the reason some sites remediated by RENA are restored better than some other sites remediated using the same method. Samples were collected from these sites before remediation, immediately after remediation and 12 weeks afterwards. Findings from the initial samples collected from the sites prior to remediation showed that site A was more contaminated than site B. Samples collected from the sites immediately after the remediation and 12 weeks after the remediation showed that RENA reduced up to 91.67 % contamination in site A and 92.04 % of the contamination in site B. The result showed that the method reduced the contamination level in the less polluted site slightly more than that of the more polluted site. The rate of decrease was immediately higher after remediation than 12 weeks after remediatlater. The rate of decrease of contamination reduced with increasing depth while the ANOVA analysis of the results showed that the effect of RENA differs with the intensity of the spill and the depth of penetration of the contamination.


Remediation, Bioremediation, Oil Spill, Land Contamination, Soil Pollution

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