Bioventing has been effectively used for removal of volatile organic compounds from unsaturated soil due to its high efficiency and low treatment cost.An experiment was conducted in laboratory using diesel as a model contaminant and one dimensional porous column filled with yellowish soil.The removal effect and its process using the two ventilation methods of pumping and injecting were studied.Results showed that pumping and injecting had the same removal process.The removal rate by pumping was faster than injecting

but the remediation efficiency was only 2.28% higher than injecting.The total volatile organic compounds(TVOC) of tail gas before and after ventilation also had the same changing process

but the value after ventilation was relatively higher.The TVOC was determined every 1

2 and 3 h one day in the 8 h ventilation

and the fluctuating degree of TVOC was showed as the order of TVOC1h>TVOC2h>TVOC3h.Available phosphorus and effective nitrogen were highly related to the diesel biodegradation efficiency in the soil.