Tracer transport modeling with the Alliances platform in the presence of evapotranspiration
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A. Constantin
Abstract
The knowledge and understanding of water flow and solute transport in the unsaturated zone is becoming increasingly important especially in mitigation of groundwater pollution. Fate of radionuclide in the geological environment is a topic to address in performance and safety assessment studies for nuclear waste disposal and may be modeled considering flow and transport in porous media. However, often, due to the heterogeneity and anisotropy of the real systems, the computer simulations may be difficult to render the real behavior. This paper addresses the simulation of a tracer transport in the unsaturated zone of the Saligny site, the potential location for the Romanian low and intermediate level waste (LILW) disposal. Computation was based on experimental data and was performed with the Alliances platform, a numerical tool developed by French organizations CEA, ANDRA and EDF. In order to obtain information regarding the solute migration in depth and the solute lateral dispersion, the dispersivity coefficients of iodine were investigated in order to match the experimental concentration determined on samples from different locations of the site. A close fit of the simulation over experimental data for the water saturation profile at a depth of 0.5 m in transient state was targeted by taking into account evapotranspiration in order to obtain a realistic estimation of the water infiltration in the porous media. Dispersivity coefficients obtained from the simulation of the tracer transport are in good order of magnitude for the unsaturated area and allow to have a good preview of the tracer plume. However, further investigations are recommended on new samples in order to validate the migration of the tracer plume as expected.
Kurzfassung
Das Wissen und das Verständnis in Bezug auf Wasserströmung und Stofftransport in der ungesättigten Zone wird immer wichtiger, insbesondere bei der Reduzierung der Verunreinigung des Grundwassers. Die Ausbreitung von Radionukliden im geologischen Umfeld ist ein wichtiges Thema bei der Bewertung der Durchführung und der Sicherheit der nuklearen Entsorgung und kann unter Berücksichtigung von Strömungs- und Transportprozessen in porösen Medien modelliert werden. Aufgrund der Heterogenität und Anisotropie realer Systeme kann die Durchführung von Computersimulationen jedoch sehr schwierig sein. Die vorliegende Arbeit befasst sich mit der Simulation eines Tracertransports in der ungesättigten Zone des Saligny Standorts, einem potentiellen Standort für die Entsorgung schwach- und mittelradioaktiver Abfälle in Rumänien. Die Berechnungen basieren auf experimentellen Daten und wurden mit Hilfe der Alliances Plattform durchgeführt, einem numerischen Programm, das von den französischen Organisationen CEA, ANDRA und EDF entwickelt wurde. Um Informationen über die Ausbreitung von Stoffen seitwärts und in der Tiefe zu erhalten wurden die Dispersivitätskoeffizienten von Jod untersucht, um so die anhand von Proben an verschiedenen Stellen des Standorts ermittelten experimentellen Konzentrationen auf einander abzustimmen. Eine gute Anpassung der simulierten und der experimentellen Daten für das Wassersättigungsprofil in einer Tiefe von 0,5 m im transienten Zustand wurde angestrebt unter Berücksichtigung der Evapotranspiration um so eine realistische Abschätzung der Infiltration des Wassers in das poröse Medium zu erhalten. Die durch die Simulation des Tracertransports erhaltenen Dispersivitätskoeffizienten stimmen größenordnungsmäßig für die ungesättigte Zone überein und erlauben eine gute Vorherschau der Tracerkonzentrationen. Es werden jedoch weitere Unterschungen an neuen Proben empfohlen um so die Ausbreitung der Tracerkonzentrationen zu validieren.
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© 2013, Carl Hanser Verlag, München
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- Development of inflatable seals for the rotatable plugs of sodium cooled fast breeder reactors: a review – Part I: key areas
- Numerical simulation of turbulent flow mixing inside a square chimney structure of a research reactor
- Thermal analysis of VWSB-IP1 at Tarapur
- Tracer transport modeling with the Alliances platform in the presence of evapotranspiration
- Seasonally gross alpha and beta activity concentration in surface water and sediments in Sır Dam Pond
- Evaluation of radioactive emissions of lignite-fired power plants in Turkey using the Analytic Hierarchy Process
- Technical Notes/Technische Mitteilungen
- Modeling of DECL accident in the reactor containment by the CONTAIN 2.0 code
- Application of the Henyey-Greenstein and Anlı-Güngör phase functions for the solution of the neutron transport equation with Legendre polynomials: Reflected critical slab problem
- Effect of gamma-radiation on sorption and precipitation of radionuclides
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- Development of inflatable seals for the rotatable plugs of sodium cooled fast breeder reactors: a review – Part I: key areas
- Numerical simulation of turbulent flow mixing inside a square chimney structure of a research reactor
- Thermal analysis of VWSB-IP1 at Tarapur
- Tracer transport modeling with the Alliances platform in the presence of evapotranspiration
- Seasonally gross alpha and beta activity concentration in surface water and sediments in Sır Dam Pond
- Evaluation of radioactive emissions of lignite-fired power plants in Turkey using the Analytic Hierarchy Process
- Technical Notes/Technische Mitteilungen
- Modeling of DECL accident in the reactor containment by the CONTAIN 2.0 code
- Application of the Henyey-Greenstein and Anlı-Güngör phase functions for the solution of the neutron transport equation with Legendre polynomials: Reflected critical slab problem
- Effect of gamma-radiation on sorption and precipitation of radionuclides
