Diesel removal from a contaminated soil by natural hydrocarbon-degrading microorganisms

A bioaugmentation procedure was applied to the bioremediation of soil contaminated with diesel at laboratory and semi-pilot-scale levels. A natural bacterial community was used to scale up a bioremediation procedure to remove the diesel. Diesel absorbed to soil was eradicated by > 60% during a 5-wk period of treatment at both levels. Diesel removal was enhanced by > 90% by an additional inoculation of the white rot fungus Pleurotus ostreatus at laboratory-scale. Biodegradation was not limited by microbial metabolic activity because high molecular weight hydrocarbons were biodegraded at the same rate. Non-degradation of the remaining hydrocarbons appeared to be the result of mass transfer limitations where hydrocarbons are not available to the microorganisms.