Formulation of Mix Design for Asphaltic Incorporation of Hydrocarbon Contaminated Soil

A cold mix design procedure was developed to incorporate hydrocarbon-contaminated soil as an ingredient of pavement base-product. The incorporation was achieved by asphaltic stabilization and encapsulation utilizing cold mix asphalt technology. The main focus is to maximize the soil in economically viable end products that meet industry standards, engineering requirements, and environmental safety requirements. Mix design was performed by several trials based on bench-scale parameters. Aggregate from a local quarry was used as one of the ingredients of mix to reduce end product cost. Soil and aggregate, prior to their incorporation, were assessed for their suitability for use in the stabilization process by bench-scale tests such as particle size distribution, sand equivalent, plasticity, density, and specific gravity. Varying amounts of affected soil, aggregate, a small amount of portland cement, and specified grades of emulsion were mixed, compacted, and tested for resistance and tensile strength. Leachate testing of the engineered product for total hydrocarbon ensured its use in a pavement base. The formulated mix design incorporated 80% of the hydrocarbon-affected soil by weight of soil-aggregate mix. Incorporating a higher percent of soil in the mix can lose the economic incentive because of the increased cost of emulsion.