title: Field data and numerical simulation of btex concentration trends under water table fluctuations: Example of a jet fuel-contaminated site in Brazil.
abstract: Mass transfer of light non-aqueous phase liquids (LNAPLs) trapped in porous media is a complex phenomenon. Water table fluctuations have been identified as responsible for generating significant variations in the concentration of dissolved hydrocarbons. Based on field evidence, this work presents a conceptual model and a numerical solution for mass transfer from entrapped LNAPL to groundwater controlled by both LNAPL saturation and seasonal water table fluctuations within the LNAPL smear zone. The numerical approach is capable of reproducing aqueous BTEX concentration trends under three different scenarios - water table fluctuating within smear zone, above the smear zone and partially within smear zone, resulting in in-phase, out-of-phase and alternating in-phase and out-of-phase BTEX concentration trend with respect to water table oscillation, respectively. The results demonstrate the model's applicability under observed field conditions and its ability to predict source zone depletion.
authors.affiliation: Laboratório de Estudos de Bacias, Centro de Estudos Ambientais, UNESP - Universidade Estadual Paulista, Av. 24A, 1515, Rio Claro, Sao Paulo, Brazil.
authors.forename: Elias Hideo
authors.initials: EH
authors.lastname: Teramoto
authors.affiliation: Departamento de Geologia Aplicada, Centro de Estudos Ambientais, UNESP - Universidade Estadual Paulista, Av. 24A, 1515, Rio Claro, Sao Paulo, Brazil. Electronic address: chang@rc.unesp.br.
authors.forename: Hung Kiang
authors.initials: HK
authors.lastname: Chang
mesh_terms: D001555:Benzene Derivatives / Q000032:analysis*; D001938:Brazil; D004784:Environmental Monitoring; D060587:Groundwater / Q000032:analysis*; D006838:Hydrocarbons / Q000032:analysis*; D008962:Models, Theoretical; D016062:Porosity; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D001555:Benzene Derivatives; D006838:Hydrocarbons; D014874:Water Pollutants, Chemical
keywords: BTEX; LNAPL saturation; Mass-transfer; Smear zone; Water table fluctuation