Phytoscreening as an efficient tool to delineate chlorinated solvent sources at a chlor-alkali facility.
Chlorinated ethenes (CE) are among the most common volatile organic compounds (VOC) that contaminate groundwater, currently representing a major source of pollution worldwide. Phytoscreening has been developed and employed through different applications at numerous sites, where it was generally useful for detection of subsurface chlorinated solvents. We aimed at delineating subsurface CE contamination at a chlor-alkali facility using tree core data that we compared with soil data. For this investigation a total of 170 trees from experimental zones was sampled and analyzed for perchloroethene (PCE) and trichloroethene (TCE) concentrations, measured by solid phase microextraction gas chromatography coupled to mass spectrometry. Within the panel of tree genera sampled, Quercus and Ulmus appeared to be efficient biomonitors of subjacent TCE and PCE contamination, in addition to the well known and widely used Populus and Salix genera. Among the 28 trees located above the dense non-aqueous phase liquid (DNAPL) phase zone, 19 tree cores contained detectable amounts of CE, with concentrations ranging from 3 to 3000 μg L-1. Our tree core dataset was found to be well related to soil gas sampling results, although the tree coring data were more informative. Our data further emphasized the need for choosing the relevant tree species and sampling periods, as well as taking into consideration the nature of the soil and its heterogeneity. Overall, this low-invasive screening method appeared useful to delineate contaminants at a small-scale site impacted by multiple sources of chlorinated solvents.
Laboratoire Chrono-Environnement (UMR 6249), Université de Bourgogne Franche-Comté, Pôle Universitaire du Pays de Montbéliard, 4 place Tharradin, BP 71427, 25211 Montbéliard, France.
Loïc
L
Yung
INOVYN France, 39500 Tavaux Cedex, France.
Jérôme
J
Lagron
INOVYN France, 39500 Tavaux Cedex, France.
David
D
Cazaux
University of Delaware, Department of Plant & Soil Sciences, Newark, DE, USA.
Matt
M
Limmer
Laboratoire Chrono-Environnement (UMR 6249), Université de Bourgogne Franche-Comté, Pôle Universitaire du Pays de Montbéliard, 4 place Tharradin, BP 71427, 25211 Montbéliard, France; Université de Lorraine, Faculté des Sciences et Technologies, BP 70239, 54506 Vandoeuvre-les-Nancy, France. Electronic address: michel.chalot@univ-fcomte.fr.
Michel
M
Chalot
D000468:Alkalies / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D060587:Groundwater / Q000032:analysis*; D054879:Halogenation; D052617:Solid Phase Microextraction / Q000379:methods; D012997:Solvents / Q000737:chemistry; D014197:Trees / Q000737:chemistry*; D014241:Trichloroethylene / Q000032:analysis*; D055549:Volatile Organic Compounds / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D000468:Alkalies; D012997:Solvents; D055549:Volatile Organic Compounds; D014874:Water Pollutants, Chemical; D014241:Trichloroethylene
Chlor-alkali facility; Chlorinated solvents; Phytoscreening; Site characterization; Soil and soil gas; Tree core