Geotechnical Properties of Lateritic Soil Contaminated with Crude Oil

Crude oil contamination is a growing geotechnical and environmental concern in many oil-producing regions. This study evaluates the impact of crude oil contamination on the engineering behavior of lateritic soil, a widely used construction material in Nigeria. Laboratory experiments were conducted on soil samples contaminated with 2%, 4%, and 6% crude oil by weight, alongside uncontaminated controls. Tests included particle size distribution, specific gravity, Atterberg limits, compaction, California Bearing Ratio (CBR), and Unconfined Compressive Strength (UCS), all carried out in accordance with BS 1377:1990 standards. The results revealed a progressive decline in critical soil properties: specific gravity dropped from 2.43 to 2.28, MDD from 1.81 to 1.68 g/cm³, while CBR and UCS values fell by over 40%. These changes indicate a substantial loss in strength, compaction efficiency, and plasticity, rendering the contaminated soil unsuitable for road or foundation applications without stabilization. The findings underscore the need for soil remediation strategies and offer valuable insights into sustainable engineering practices in petroleum-impacted environments.