The scope of this work is to discuss the proper choice of macrodispersion coefficients in modeling contaminant transport through the advection dispersion equation (ADE). It is common to model solute concentrations in transport by groundwater with the aid of the ADE. Spreading is quantified by macrodispersivity coefficients, which are much larger than the laboratory observed pore-scale dispersivities. In the frame of stochastic theory, longitudinal macrodispersivity is related to the hydraulic conductivity spatial variability via its statistical moments (mean, variance, integral scales), which are generally determined by geostatistical analysis of field measurements. In many cases, especially for preliminary assessment of contaminant spreading, these data are not available and ad-hoc values are adopted by practitioners. The present study aims at recommending dispersivity values based on a thorough analysis of tens of field experiments. Aquifers are classified as of weak, medium and high heterogeneity and for each class a range of macrodispersivity values is recommended. Much less data are available for the transverse macrodispersivities, which are significantly smaller than the longitudinal one. Nevertheless, a few realistic values based on field data, are recommended for applications. Transport models using macrodispersivities can predict mean concentrations, different from the local ones. They can be used for estimation of robust measures, like plumes spatial moments, longitudinal mass distribution and breakthrough curves at control planes.

Evidence Based Estimation of Macrodispersivity for Groundwater Transport Applications / Zech, Alraune; Attinger, Sabine; Bellin, Alberto; Cvetkovic, Vladimir; Dagan, Gedeon; Dietrich, Peter; Fiori, Aldo; Teutsch, Georg. - In: GROUND WATER. - ISSN 0017-467X. - ELETTRONICO. - 2022, 61:3(2023), pp. 346-362. [10.1111/gwat.13252]

Evidence Based Estimation of Macrodispersivity for Groundwater Transport Applications

Bellin, Alberto;
2023-01-01

Abstract

The scope of this work is to discuss the proper choice of macrodispersion coefficients in modeling contaminant transport through the advection dispersion equation (ADE). It is common to model solute concentrations in transport by groundwater with the aid of the ADE. Spreading is quantified by macrodispersivity coefficients, which are much larger than the laboratory observed pore-scale dispersivities. In the frame of stochastic theory, longitudinal macrodispersivity is related to the hydraulic conductivity spatial variability via its statistical moments (mean, variance, integral scales), which are generally determined by geostatistical analysis of field measurements. In many cases, especially for preliminary assessment of contaminant spreading, these data are not available and ad-hoc values are adopted by practitioners. The present study aims at recommending dispersivity values based on a thorough analysis of tens of field experiments. Aquifers are classified as of weak, medium and high heterogeneity and for each class a range of macrodispersivity values is recommended. Much less data are available for the transverse macrodispersivities, which are significantly smaller than the longitudinal one. Nevertheless, a few realistic values based on field data, are recommended for applications. Transport models using macrodispersivities can predict mean concentrations, different from the local ones. They can be used for estimation of robust measures, like plumes spatial moments, longitudinal mass distribution and breakthrough curves at control planes.
2023
3
Zech, Alraune; Attinger, Sabine; Bellin, Alberto; Cvetkovic, Vladimir; Dagan, Gedeon; Dietrich, Peter; Fiori, Aldo; Teutsch, Georg
Evidence Based Estimation of Macrodispersivity for Groundwater Transport Applications / Zech, Alraune; Attinger, Sabine; Bellin, Alberto; Cvetkovic, Vladimir; Dagan, Gedeon; Dietrich, Peter; Fiori, Aldo; Teutsch, Georg. - In: GROUND WATER. - ISSN 0017-467X. - ELETTRONICO. - 2022, 61:3(2023), pp. 346-362. [10.1111/gwat.13252]
File in questo prodotto:
File Dimensione Formato  
Groundwater - 2022 - Zech - Evidence based Estimation of Macrodispersivity for Groundwater Transport Applications.pdf

Open Access dal 17/09/2023

Descrizione: Articolo
Tipologia: Post-print referato (Refereed author’s manuscript)
Licenza: Creative commons
Dimensione 1.28 MB
Formato Adobe PDF
1.28 MB Adobe PDF Visualizza/Apri
Groundwater - 2022 - Zech - Evidence Based Estimation of Macrodispersivity for Groundwater Transport Applications.pdf

accesso aperto

Tipologia: Versione editoriale (Publisher’s layout)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 641.89 kB
Formato Adobe PDF
641.89 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11572/355243
Citazioni
  • ???jsp.display-item.citation.pmc??? 0
  • Scopus 10
  • ???jsp.display-item.citation.isi??? 10
social impact