Diesel-contaminated soil was treated with Fenton's oxidant, from hydrogen peroxide. Soil samples were collected during the earthmoving of RNEST Oil Refinery (Petrobras). A factorial design 3(3) evidenced that the concentration of iron ions [Fe2+] was the variable with the most statistically significant effect in all experiments. The oxidation efficiency was found to be 57 % of total organic carbon (TOC) and 78 % of polycyclic aromatic hydrocarbon (PAH) removal. Moreover, the sum of low-molecular-weight PAHs on treated soil and the sum of high-molecular-weight PAHs was determined. Soil remediation in a pilot-scale reactor led to a reduction of nearly 80 % in total PAHs. Toxicity assessment with Californian red earthworms as bioindicator evidenced the mineralization of PAHs.