A method for cleaning a soil containing contaminants is disclosed. At least one heat-conductive pipe, is introduced in the soil which is in good working condition under negative pressure and provided with perforations. The soil is heated by thermal conduction by circulating a heated fluid through the heat-conductive pipe thereby obtaining a contaminant vapor. The contaminant vapor is forced into the heat-conductive pipe through a negative pressure present in the pipe, and transported in the heat-conductive pipe out of the soil. The contaminant vapor is incinerated in order to at least partly remove the soil contaminants. The method also involves the step of re-using the heat energy obtained by incinerating the contaminant vapor for heating the soil in order to vaporize the remaining contaminants in the soil. A nearly closed loop system for cleaning a soil containing contaminants is disclosed.