title: Analyzing tree cores to detect petroleum hydrocarbon-contaminated groundwater at a former landfill site in the community of Happy Valley-Goose Bay, eastern Canadian subarctic.
abstract: This research examines the feasibility of analyzing tree cores to detect benzene, toluene, ethylbenzene, and m, p, o-xylene (BTEX) compounds and methyl tertiary-butyl ether (MTBE) in groundwater in eastern Canada subarctic environments, using a former landfill site in the remote community of Happy Valley-Goose Bay, Labrador. Petroleum hydrocarbon contamination at the landfill site is the result of environmentally unsound pre-1990s disposal of households and industrial solid wastes. Tree cores were taken from trembling aspen, black spruce, and white birch and analyzed by headspace-gas chromatography-mass spectrometry. BTEX compounds were detected in tree cores, corroborating known groundwater contamination. A zone of anomalously high concentrations of total BTEX constituents was identified and recommended for monitoring by groundwater wells. Tree cores collected outside the landfill site at a local control area suggest the migration of contaminants off-site. Tree species exhibit different concentrations of BTEX constituents, indicating selective uptake and accumulation. Toluene in wood exhibited the highest concentrations, which may also be due to endogenous production. Meanwhile, MTBE was not found in the tree cores and is considered to be absent in the groundwater. The results demonstrate that tree-core analysis can be useful for detecting anomalous concentrations of petroleum hydrocarbons, such as BTEX compounds, in subarctic sites with shallow unconfined aquifers and permeable soils. This method can therefore aid in the proper management of contamination during landfill operations and after site closures.
authors.affiliation: Labrador Institute, Memorial University of Newfoundland, 219 Hamilton River Road, P.O. Box 490, Station B, Happy Valley-Goose Bay, NL, A0P 1E0, Canada. merline.fonkwe@mun.ca.
authors.forename: Merline L D
authors.initials: ML
authors.lastname: Fonkwe
authors.affiliation: Department of Environmental Engineering, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark.
authors.forename: Stefan
authors.initials: S
authors.lastname: Trapp
mesh_terms: D061006:Bays; D001554:Benzene / Q000032:analysis; D001555:Benzene Derivatives; D002170:Canada; D005240:Feasibility Studies; D008401:Gas Chromatography-Mass Spectrometry; D060587:Groundwater / Q000737:chemistry*; D006838:Hydrocarbons / Q000032:analysis; D010578:Petroleum / Q000032:analysis*; D014050:Toluene / Q000032:analysis; D014197:Trees / Q000737:chemistry*; D064091:Waste Disposal Facilities; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014992:Xylenes / Q000032:analysis
chemical_list: D001555:Benzene Derivatives; D006838:Hydrocarbons; D010578:Petroleum; D014874:Water Pollutants, Chemical; D014992:Xylenes; D014050:Toluene; D001554:Benzene; C004912:ethylbenzene
keywords: BTEX compounds; Labrador; MTBE; Organic pollutants; Phytoscreening; Preliminary site assessments; Remote location; Solid waste disposal