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Updated: Aug 11, 2026
10:26
Transport of Surface-modified Carbon Nanotubes through a Soil Column
Published on: April 2, 2015
Field scale DNAPLs transport under nonequilibrium sorption conditions
1School of Mechanical, Aerospace, and Civil Engineering, The University of Manchester, Manchester, M60 1QD, United Kingdom.
Summary
This study models dense nonaqueous phase liquid (DNAPL) desorption from aquifer solids. Results show slow, long-term TCE contaminant diffusion, highlighting the need for extended remediation strategies in heterogeneous sites.
Area of Science:
- Environmental Science
- Hydrogeology
- Geochemistry
Background:
- Dense nonaqueous phase liquids (DNAPLs) pose significant challenges for aquifer remediation.
- Trichloroethylene (TCE) is a common DNAPL contaminant.
- Heterogeneous aquifer properties complicate contaminant transport and remediation.
Purpose of the Study:
- To simulate the desorption of DNAPLs, specifically TCE, from solid particles in heterogeneous aquifers.
- To model the fate and transport of NAPLs under nonequilibrium sorption conditions.
- To assess long-term contaminant release post-remediation.
Main Methods:
- Development of a computer program for simulating NAPL fate and transport in porous media.
- Application of the model to a field-scale site (Hill Air Force Base, Utah) with known DNAPL contamination.
- Incorporation of site-specific data including permeability, grain size distribution, and sorptive properties.
Main Results:
- Simulations show TCE desorbing from solid particles over time, forming contaminant plumes.
- Contaminant diffusion rates are initially fast, then become very slow, requiring years for substantial desorption.
- Aquifer heterogeneity causes local variations in fluid-phase contaminant concentrations.
Conclusions:
- Long-term desorption is a critical factor in DNAPL remediation, extending beyond initial cleanup.
- Heterogeneity significantly influences contaminant distribution and release dynamics.
- Numerical modeling provides valuable insights for predicting post-remediation contaminant behavior.
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