Natural attenuation of xenobiotic organic compounds in a landfill leachate plume (Vejen, Denmark)

• Published in: Journal of contaminant hydrology Vol. 65; no. 3; pp. 269 - 291
• Main Authors: Baun, Anders, Reitzel, Lotte A, Ledin, Anna, Christensen, Thomas H, Bjerg, Poul L
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2003; Elsevier Science
• Subjects: Bacteria; Degradation products; Denmark; Denmark, Vejen; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental Monitoring; Eukaryota; Exact sciences and technology; Geochemistry; Groundwater; Hydrogeology; Hydrology. Hydrogeology; Kinetics; Landfill leachate plume; Mineralogy; Natural attenuation; Pollution, environment geology; Refuse Disposal - methods; Silicates; Soil Pollutants - analysis; Soil Pollutants - metabolism; Soil Pollutants - toxicity; Toxicity; Water geochemistry; Water Movements; Water Pollutants - analysis; Water Pollutants - metabolism; Water Pollutants - toxicity; Xenobiotic organic compounds; Xenobiotics - analysis; Xenobiotics - metabolism; Xenobiotics - toxicity; Denmark; Scandinavia; Xenobiotic organic compounds; Degradation products; Natural attenuation; Groundwater; Landfill leachate plume; Toxicity; toxicity; phenols; attenuation; naphthalene; plumes; hazardous wastes; ground water; degradation; pollution; xylene; remediation; landfills; anaerobic environment; organic carbon; herbicides; chlorides; detection; Europe; chemical wastes; halides; benzene; industrial waste; dilution; solid phase; organic compounds; leachate; toluene
• DOI: 10.1016/S0169-7722(03)00004-4
• ISSN: 0169-7722

Demonstration of natural attenuation of xenobiotic organic compounds (XOCs) in landfill leachate plumes is a difficult task and still an emerging discipline within groundwater remediation. One of the early studies was made at the Vejen Landfill in Denmark in the late 1980s, which suggested that natural attenuation of XOCs took place under strongly anaerobic conditions within the first 150 m of the leachate plume. This paper reports on a revisit to the same plume 10 years later. Within the strongly anaerobic part of the plume, 49 groundwater samples were characterized with respect to redox-sensitive species and XOCs. The analytical procedures have been developed further and more compounds and lower detection limits were observed this time. In addition, the samples were screened for degradation intermediates and for toxicity. The plume showed fairly stationary features over the 10-year period except that the XOC level as well as the level of chloride and nonvolatile organic carbon (NVOC) in the plume had decreased somewhat. Most of the compounds studied were subject to degradation in addition to dilution. Exceptions were benzene, the herbicide Mecoprop (MCPP), and NVOC. In the early study, NVOC seemed to degrade in the first part of the plume, but this was no longer the case. Benzyl succinic acid (BSA) was for the first time identified in a leachate plume as a direct indicator, and as the only intermediate of toluene degradation. Toxicity measurements on solid phase-extracted (SPE) samples revealed that toxic compounds not analytically identified were still present in the plume, suggesting that toxicity measurements could be helpful in assessing natural attenuation in leachate plumes.