Title: Geochemical and Isotope Study of Trichloroethene Degradation in a Zero-Valent Iron Permeable Reactive Barrier: A Twenty-Two-Year Performance Evaluation 
Resource Type: document --> technical publication --> journal article 
Country: USA 
Language(s): English
 
Year: 2019 
Author 1/Producer: Wilkin, Richard T.,  
Other Authors/Producers: Tony R. Lee, M. Sexton, Steven D. Acree, R. Puls, D. Blowes, C. Kalinowski, J. Tilton, AND L. Woods. 
Author / Producer Type: University research group / research institute 
Journal: ENVIRONMENTAL SCIENCE & TECHNOLOGY 
Journal Web Link: https://doi.org/10.1021/acs.est.8b04081  
Start Page: 296 
End Page: 306 
Volume: 53 
Publisher: American Chemical Society,  
Publisher City: Washington, DC 
Publisher Country: USA 
Publisher web link (root): https://cfpub.epa.gov/si/si_public_record_report.cfm?Lab=NRMRL&dirEntryId=343800
ISSN: DOI 10.1021/acs.est.8b04081 
Article Weblink (=direct link): https://pubs.acs.org/doi/10.1021/acs.est.8b04081  
EUGRIS Keyword(s): Contaminated land-->Remediation options-->Permeable reactive barriers
Contaminated land-->Soil and groundwater processes-->Contaminant hydrology
Contaminated land-->Soil and groundwater processes-->Hydrogeology
Contaminated land-->Soil and groundwater processes-->Microbiology
 
Short description: Long-term data on the performance of in-situ remediation technologies for groundwater cleanup are needed to improve system designs and to guide selection of remedial measures that best match site-specific hydrogeochemical conditions. The study examined a twenty-two-year history of trichloroethylene (TCE) treatment by zero-valent iron in a Permeable Reactive Barrier (PRB). Degradation products included cis-dichloroethene (cis-DCE), vinyl chloride (VC), ethene, ethane, >C4 compounds, and possibly CO2(aq) and methane. Abiotic patterns of TCE degradation were indicated by the distribution of degradation products and by compound-specific stable isotope data. ?13C values of methane within and down-gradient of the PRB varied widely and covered most of the isotopic range encountered in natural methanogenic systems. Methanogenesis is a sink for inorganic carbon in zero-valent iron PRBs that competes with carbonate mineralization and this process is important for understanding pore-space clogging and longevity of iron-based PRBs. This study provides the longest available record of treatment performance of chlorinated compounds by iron metal.  
Submitted By: Professor Paul Bardos WhoDoesWhat?      Last update: 11/02/2019