Using Tree Core Samples to Monitor Natural Attenuation and Plume Distribution After a PCE Spill
The potential of using tree core samples to detect and monitor natural attenuation of perchloroethene (PCE) in groundwater was investigated at a PCE-contaminated site. In the area of the known plume with PCE concentrations between 0.004 and >40 mg/L, cores were collected from tree trunks at a height of about 1 m above ground surface. Tree sampling of the site was completed in under six hours. Chlorinated ethenes were analyzed by headspace GC/MS. PCE (0.001 to 7 mg/kg) and natural attenuation products, TCE (<0.001 to 0.4 mg/kg) and c-DCE (<0.001 to 0.46 mg/kg), were detected in tree cores. 1,1-dichloroethene and vinyl chloride were not detected, corresponding to very low concentrations in the groundwater. The contaminant plume was mapped from the concentrations measured in trees, which delineated a probable hot spot area that had been undetected in decades of traditional groundwater monitoring. Natural attenuation products in tree cores increased with distance from the known source area. Concentrations of PCE and reductive dechlorination products in tree cores were correlated with the corresponding groundwater concentrations.Within a range of limitations, tree-core sampling provides a rapid, reliable and inexpensive method to investigate the extent of shallow contamination by chlorinated ethenes in soil and groundwater.
M. Larsen et al., "Using Tree Core Samples to Monitor Natural Attenuation and Plume Distribution After a PCE Spill," Environmental Science and Technology, American Chemical Society (ACS), Jan 2008.
The definitive version is available at http://dx.doi.org/10.1021%2Fes0717055
Civil, Architectural and Environmental Engineering
Organisation for Economic Co-operation and Development
Keywords and Phrases
Natural Attenuation; Perchloroethene; Tree Core Samples; Groundwater
Article - Journal
© 2008 American Chemical Society (ACS), All rights reserved.