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LINES OF EVIDENCE FOR NA FOR ORGANIC COMPOUNDS AND THE USE OF COMPOUND SPECIFIC ISOTOPE ANALYSIS
Citation:
WILSON, J. T. LINES OF EVIDENCE FOR NA FOR ORGANIC COMPOUNDS AND THE USE OF COMPOUND SPECIFIC ISOTOPE ANALYSIS. Presented at Workshop for EPA of Taiwan on Natural Attenuation as Remediation for Contaminated Sites, Taipei, TAIWAN, October 26 - 27, 2006.
Impact/Purpose:
To inform the public.
Description:
The strongest line of evidence is a reduction in concentration over time. However, this only provides evidence of natural attenuation of the source area. It is difficult to determine the rate of natural attenuation through biodegradation with distance along a flow path in the aquifer. Compound specific stable isotope analyses can provide an unambiguous conservative boundary on the extent of biodegradation along the flow path for some contaminants including chlorinated solvents, benzene, and MTBE. On the other hand, an analysis of DNA in ground water samples to estimate the number of gene copies of active organisms does not provide a quantitative estimate of the rate of biological reductive dechlorination in the aquifer system.