Monitoring in situ biodegradation of hydrocarbons by using stable carbon isotopes

Carbon isotope data demonstrate the utility of an isotopic technique in identifying the presence of carbon dioxide generated from aerobic biodegradation of hydrocarbons in three jet fuel-contaminated soils. The C isotopic composition of soil gas CO sub(2) from contaminated sites decreases with increasing CO sub(2) concentration and becomes nearly constant at CO sub(2) concentrations exceeding 5%. The lower delta super(13)C values in samples with higher CO sub(2) content suggest that increased CO sub(2) content is almost completely from hydrocarbon biodegradation.