Researchers believe one approach is using a formula based on the ratio of various chemical markers in contaminated soil to determine if petroleum hydrocarbons are being degraded by microbes, or lost by escaping into the atmosphere, leaching into the ground or some other way. At the symposium, Dr. Mills will present a related study he did with his colleagues. It revealed that these ratios cannot be generalized. Instead they must be specific to the various site conditions, including the weathered state of the oil, the nutrient supply in the soil and the assemblage of microorganisms in the soil. Future research will look intensively at the effects of the weathered state of the oil in regard to changes in marker ratios during the biodegradation process, Dr. Mills says.
Scientists know that the more weathered the oil, the harder it is to degrade.
S.C. The Energy Department funds ecological research at SRS by the University of Georgia's Savannah River Ecology Laboratory.