Abstract: A soil washing apparatus utilizing a water-based surfactant to separate contaminants from soil particles with particle sizes within a predetermined range. After removing the surfactant/contaminant/water mixture from the soil particles, the soil is returned to the remediation site, while the mixture is processed through an oil/water separator. Oil and contaminants are then disposed of, while the water and surfactant are centrifuged, and the resulting supernatant is recycled back into the apparatus for use with more contaminated soil. A method of soil washing is also provided.