Modeling the Dynamics of Fermentation and Respiratory Processes in a Groundwater Plume of Phenolic Contaminants Interpreted from Laboratory- to Field-Scale

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• 作者：Ian A. Watson ; Sascha E. Oswald ; Steven A. Banwart ; Roger S. Crouch ; and Steven F. Thornton
• 刊名：Environmental Science & Technology
• 出版年：2005
• 出版时间：November 15, 2005
• 年：2005
• 卷：39
• 期：22
• 页码：8829 - 8839
• 全文大小：761K
• 年卷期：v.39,no.22(November 15, 2005)
• ISSN：1520-5851

文摘

A biodegradation model with consecutive fermentationand respiration processes, developed from microcosmexperiments and simulated mathematically with microbialgrowth kinetics, has been implemented into a field-scale reactive transport model of a groundwater plume ofphenolic contaminants. Simulation of the anaerobicplume core with H₂ and acetate as intermediate productsof biodegradation allows the rates and parameter valuesfor fermentation processes and individual respiratory terminalelectron accepting processes (TEAPS) to be estimatedusing detailed, spatially discrete, hydrochemical field data.The modeling of field-scale plume development includesconsideration of microbial acclimatization, substrate toxicitytoward degradation, bioavailability of mineral oxides, andadsorption of biogenic Fe(II) species in the aquifer, identifiedfrom complementary laboratory process studies. Theresults suggest that plume core processes, particularlyfermentation and Fe(III)-reduction, are more important fordegradation than previously thought, possibly with agreater impact than plume fringe processes (aerobicrespiration, denitrification, and SO₄-reduction). Theaccumulation of acetate as a fermentation product withinthe plume contributes significantly to the mass balancefor carbon. These results demonstrate the value of quantifyingfermentation products within organic contaminant plumesand strongly suggest that the conceptual model selectedfor reactive processes plays a dominant role in the quantitativeassessment of risk reduction by naturally occurringbiodegradation processes.