Some petroleum products can be very thick and sticky. These types of petroleum products can clog the soil so that water and air is difficult to move to plant roots, resulting in drought-like symptoms. This contamination can occur directly through leaks, car accidents, and spills. Leakage of natural gas from the gas distribution system affects the physical, chemical and biological processes in the soil. Particularly the microbial oxidation of methane is then of predominant importance for the composition of the soil gas phase. A porous surface, like concrete or soil, will absorb gasoline and it may take a long time to evaporate completely. Soil vapor extraction (SVE) is a common and typically effective physical treatment process for remediation of volatile contaminants in unsaturated soils. Higher venting velocities led to more rapid removal of gasoline from sandy soil columns and increased soil moisture content led to faster gasoline extraction rates. SVP has the highest efficiency for gasoline removal from sandy soils and can remediate the vadose zone effectively to meet the soil guideline values for protection of groundwater.