Utilization of Stable Carbon Isotope in the Verification of Bioremediation of Chlorinated Hydrocarbons
Abstract
The overall goal of this work was to test the feasibility of using stable carbon isotope analysis to verify in situ biodegradation of hydrocarbons and chlorinated ethenes under aerobic conditions. Specific objectives were to 1) determine d13C values for TCE and the various compounds to be used as co-substrates for TCE degradation; 2) evaluate effects of aerobic biodegradation of co-substrate compounds and TCE on gross fractionation of carbon isotopes as measured in the resulting CO2; 3) test the carbon isotope method for its ability to differentiate the source of the CO2 resulting from aerobic biodegradation; and 4) use samples from an appropriately contaminated bioventing site. Different degrees of fractionation were measured in both pure and mixed cultures for the different compounds tested in this study. Fractionation for toluene was slightly more negative than the starting compound. For JP-4, the fractionation of JP-4 resulted in d13C values much more negative than the starting compound. Fractionation for TCE results in d13C values more positive, indicating the CO2 had a higher percentage of 13C than the source compound. A mixture of toluene and TCE had a d13C value intermediate between the two. These results indicate, with the d13C values for these co-substrates and chlorinated ethenes sufficiently different, the degradation of one or the other can be determined. When both are being degraded an intermediate value can be obtained.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1996
- Accession Number
- ADA359310
Entities
People
- K. Van De Velde
- M. F. Deflaun
- R. J. Steffan