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Sternberg, Steven P. K.

doi:10.1023/a:1025708313812

Cited by 22 publications

(3 citation statements)

References 28 publications

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“…In other words, the dispersion coefficient for layered heterogeneous soils was 1.96 times less than the homogeneous soils. This finding is consistent with studies of Van der Zee (2020), Leij & van Genuchten (1995);Al-Tabbaa et al (2000); Sternberg (2004), Zhang & Wu (2016). 2.…”

Section: Discussionsupporting

confidence: 92%

An experimental study on the determination of dispersion coefficient in layered soils

et al. 2021

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Dispersivity is a measurable parameter in soil porous media that is used for studying the transport of contaminants to groundwater. The value of this parameter depends on various factors, including the kind of porous media (homogeneous or heterogeneous), flow velocity, initial contaminant concentration, travel distance, and sampling method. A physical model with dimensions of 0.10 m in width, 0.80 m in height, and 1.10 m in length was constructed to investigate the effects of these parameters on the dispersivity value. The stratified soil consisted of three 20-cm-thick layers containing fine-grained, medium-grained, and coarse-grained soil. Sodium chloride solutions with electrical conductivity values of 10, 14, and 19 dS/m were used as the contaminants. Flow was forced through the layered heterogeneous soils at three discharge velocities of 17.58, 22.02, and 26.18 × 10−5 m/s. The point and mixed sampling methods were used. The results indicated that the soil dispersivity values in the layered heterogeneous soils and homogeneous soil were influenced by contaminant concentration, flow velocity, and travel distance. Moreover, the dispersivity values obtained by point sampling were lower than those obtained using the mixed sampling method, and the mean dispersivity value in the layered heterogeneous soils was lower than that of the homogeneous soil.

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Section: Discussionsupporting

confidence: 92%

An experimental study on the determination of dispersion coefficient in layered soils

et al. 2021

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“…In many investigations, dispersivity is estimated through adjustments until the modeled concentrations best approximate observed concentrations [2][3][4][5][6][7][8][9][10][11][12]. An alternative approach to estimating dispersivity is through field and laboratory experiments conducted at different spatial scales [12][13][14][15][16][17][18][19][20][21][22]. However, field tracer tests are often time-consuming and very expensive.…”

Section: Introductionmentioning

confidence: 99%

Determination of Contaminant Transport Parameters for a Local Aquifer by Numerical Modeling of Two Plumes: Trichloroethylene and Hexavalent Chromium

Ibn Salam,

Waldron,

Schoefernacker

et al. 2024

Hydrology

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The municipal wellfield in Collierville, Tennessee, is contaminated with trichloroethylene (TCE) and hexavalent chromium (Cr (VI)) due to industrial operations dating back to the 1970s and 1980s. This study aims to elucidate the aquifer’s contaminant transport mechanisms by determining longitudinal and transverse dispersivities through inverse modeling. Utilizing MT3DMS for contaminant transport simulation, based on a well-calibrated groundwater flow model, and leveraging Python’s multiprocessing library for efficiency, the study employs a trial-and-error methodology. Key findings reveal that longitudinal dispersivity values range from 5.5 m near the source to 20.5 m further away, with horizontal and vertical transverse dispersivities between 0.28 m and 3.88 m and between 0.03 m and 0.08 m, respectively. These insights into the aquifer’s dispersivity coefficients, which reflect the scale-dependent nature of longitudinal dispersivity, are crucial for optimizing remediation strategies and achieving cleanup goals. This study underscores the importance of accurate parameter estimation in contaminant transport modeling and contributes to a better understanding of contaminant dynamics in the Collierville wellfield.

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“…This approach allows determination of tracer concentration at distance x and time t provided that the flow rate, porosity and dispersion coefficients of the medium are known. Several studies have demonstrated that the experimentally determined dispersion coefficient for any given macroscopic uniform flow conditions in a homogeneous porous medium is constant (Han et al 1985;Srivastava et al 1992;Sternberg 2004). However, it is well known that this coefficient has spatial dependency, and therefore is not constant for heterogeneous media (Domenico and Robbins 1984;Gelhar et al 1992;Rajaram and Gelhar 1993), even at laboratory scale (Siddiqui et al 2000;Hidajat et al 2004;Fourar et al 2005;Bauget and Fourar 2008).…”

Section: Introductionmentioning

confidence: 99%

Non-Fickian Description of Tracer Transport Through Heterogeneous Porous Media

Fourar

Radilla

2009

Transp Porous Med

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The porosity and the in situ concentration of tracer testing through different heterogeneous carbonate cores were performed using X-ray computed tomography. The results were interpreted using three approaches: the convection-diffusion equation, the arrival time moments and the stratified model. The results showed that (i) the Fickian approach led to a dispersion coefficient varying along each sample (ii) the statistical approach led to a power law of the variance of the arrival time as a function of the distance and (iii) the stratified model allowed quantification of the heterogeneity factor, which also appeared to be a power function of the distance. These data suggest that the temporal moments approach and the stratified model, but not the classical Fickian approach, are suitable for describing tracer transport through heterogeneous media at the core scale.

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Untitled

Cited by 22 publications

References 28 publications

An experimental study on the determination of dispersion coefficient in layered soils

An experimental study on the determination of dispersion coefficient in layered soils

Determination of Contaminant Transport Parameters for a Local Aquifer by Numerical Modeling of Two Plumes: Trichloroethylene and Hexavalent Chromium

Non-Fickian Description of Tracer Transport Through Heterogeneous Porous Media

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