Physical properties of soils contaminated by oil lakes, Kuwait

Abstract

In preparation for a marine assault by the coalition forces, the Iraqi Army heavily mined Kuwait's coastal zone and the oil fields. Over a million of mines were placed on the Kuwait soil. Burning of 732 oil wells in the State of Kuwait due to the Iraqi invasion caused damages which had direct and indirect effect on the environment. A total of 20–22 million barrels of spilled crude oil were collected in natural desert depressions and drainage network which formed more than 300 oil lakes. The total area covered with oil reached 49 km². More than 375 trenches revealed the existence of hard, massive caliche (CaCO₃) subsoil which prevent leached oil from reaching deeper horizons, and limited the maximum depth of penetration to 1.75 m. Total volume of soil contaminated reached 22,652,500 m³ is still causing environmental problems and needs an urgent cleaning and rehabilitation. Kuwait Oil Company has recovered approximately 21 million barrels from the oil lakes since the liberation of Kuwait. In our examined representative soil profiles the oil penetration was not deeper than 45 cm. Infiltration rate, soil permeability, grain size distribution, aggregates formation and water holding capacity were assessed.