An estimated 50 000 1 of diesel fuel contaminated soil over a depth of 1.5 to 3.5 m (approximately 1.5% by weight in the soil) following fuel recovery operations at the site of a diesel spill. Laboratory treatability identified oxygen supply treatment as having significant potential to enhance bioremediation of the soil in situ. A bioventing system was designed and tested on a quarter of the site. Venting alone over a period of six months reduced total hydrocarbon concentrations by 10 to 30% to a depth of 3 m. Venting with nutrient addition resulted in a further reduction of 30% over a subsequent 6 month period to the full depth of 3.5 m.