C, Cl and H compound-specific isotope analysis to assess natural versus Fe(0) barrier-induced degradation of chlorinated ethenes at a contaminated site

Compound-specific isotopic analysis of multiple elements (C, Cl, H) was tested to better assess the effect of a zero-valent iron-permeable reactive barrier (ZVI-PRB) installation at a site contaminated with tetrachloroethene (PCE) and trichloroethene (TCE). The focus was on (1) using 13C to evaluate...

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Detalles Bibliográficos
Autores: Audí Miró, Carme, Cretnik, S., Torrentó, Clara, Rosell, Mònica, Shouakar-Stash, O., Otero Pérez, Neus, Palau, Jordi, Elsner, M., Soler i Gil, Albert
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/155353
Acceso en línea:https://hdl.handle.net/2445/155353
Access Level:acceso abierto
Palabra clave:Contaminació de l'aigua
Depuració d'aigües residuals
Hidrologia d'aigües subterrànies
Isòtops
Water pollution
Purification of sewage
Groundwater hydrology
Isotopes
Descripción
Sumario:Compound-specific isotopic analysis of multiple elements (C, Cl, H) was tested to better assess the effect of a zero-valent iron-permeable reactive barrier (ZVI-PRB) installation at a site contaminated with tetrachloroethene (PCE) and trichloroethene (TCE). The focus was on (1) using 13C to evaluate natural chlorinated ethene biodegradation and the ZVI-PRB efficiency; (2) using dual element 13C-37Cl isotopic analysis to distinguish biotic from abiotic degradation of cis-dichloroethene (cis-DCE); and (3) using 13C-37Cl-2H isotopic analysis of cis-DCE and TCE to elucidate different contaminant sources. Both biodegradation and degradation by ZVI-PRB were indicated by the metabolites that were detected and the 13C data, with a quantitative estimate of the ZVI-PRB efficiency of less than 10% for PCE. Dual ele- ment 13C-37Cl isotopic plots confirmed that biodegradation was the main process at the site including the ZVI-PRB area. Based on the carbon isotope data, approximately 45% and 71% of PCE and TCE, respec- tively, were estimated to be removed by biodegradation. 2H combined with 13C and 37Cl seems to have identified two discrete sources contributing to the contaminant plume, indicating the potential of 2 H to discriminate whether a compound is of industrial origin, or whether a compound is formed as a daughter product during degradation.