Abstract: A transportable apparatus that can be utilized for on-site removal of contaminating hydrocarbons from gravel and soils. The apparatus functions by depositing the gravel and soils as a layer onto a specially constructed belt or screw conveyor which operates so that gravel and soils are not only conveyed through an exposure to multiple overhead steam nozzles or jets, but also agitated to separate the individual particles so that each particle's entire surface is exposed to superheated steam. The superheated steam volatizes the lighter hydrocarbons and thins the heavier hydrocarbons. The volatilized hydrocarbons are evacuated from the conveyor and condensed to liquid form. The thinned heavier hydrocarbons are discharged with the gravel and soils into a sump, where the hydrocarbons are captured. The clean gravel and soils are removed from the apparatus by a loader.