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Throughout the world,the oil industry generates highly polluted soils heavily contaminated with crude oil or petroleum residues generated by refinery activities.In partnership with the TOTAL company a global strategy starting from treatment and ending with re-use of the contaminated soils has been studied through two examples.The fmal objective of the work is to propose a treatment strategy adapted to the final use of the land.The selected initial treatment is a bioremediation technology either biopile or land-farming.This choice based on both feasibility constraints and environmental considerations has proved to be efficient enough to decrease by 50 to 80 % the initial organic pollutant loads of the contaminated materials.However dealing with the residual pollution in order to mitigate unwanted environmental consequences remains a major concern and requires adapted technological solutions.Two experimental cases studies corresponding to the two major steps of the treatment strategy have been chosen to illustrate the proposed methodology.The first was the initial biopile treatment.This was performed on a soil contaminated by petroleum byproducts and excavated at about 1.5 m deep.The biopile consisted of three concrete basement plots 0.2×3 m) covered by a black tent to avoid meteoric water infiltration where 30 m3 of the polluted soil (24 tons) were engineered.To improve biodegradation of organics nutrients and straw were added.Agricultural fertilizers were mixed by thirds (on day 0 and months 1 and 3) to reach a C/N/P ratio of 100/9/1 and promote biological activity.The soil was initially mixed with straw (15% v/v) to increase air diffusion,stimulate micro-organisms growth and improve the soil structure.Moreover water was periodically added to keep moisture content between 80 to 100 % of the water holding capacity of the soil.The evolution of the composition of the pollutants was assessed through the 15 months of the experiment and completed with toxicity measurements.Results showed that biodegradation of low molecular weight organic molecules was very efficient and the decrease in efficiency of the remediation after 15 months was due to a relative enrichment in macromolecules more difficult to biodegrade.The second experiment consisted in evaluating the potential use of such treated soil for plant growth.Indeed in most cases,the treated soil is meant to be reintroduced in the environment for landscaping.A treated soil coming from Indonesia was selected.Initially contaminated with crude oil and drilling fluids it had been treated in a similar biopile as the one presented above.Experiments were run to evaluate its agronomic potential and the further behaviour of residual pollution.Results showed that the material had very strong hydrophobic properties responsible for a very poor agronomic potential.The soil was quite impossible to wet and displayed therefore no available water for growing plants.Residual pollution did not transfer to the soil solution and no toxic or phytotoxic effect was detected.Dealing with this type of soil was more of an agronomic issue than a treatment problem.Strategy involving soil construction should then be considered as finishing treatment.