Transport and biological fate of toluene in low-permeability soils

Journal Article · Thu Dec 31 04:00:00 EST 1998 · Ground Water Monitoring and Remediation

DOI:https://doi.org/10.1111/j.1745-6592.1998.tb00607.x· OSTI ID:290207

Venkatraman, S N; Kosson, D S; Schuring, J R

The effect of simultaneous sorption, diffusion, and biodegradation on the fate and transport of toluene in low-permeability soil formations was examined. A transport model accounting for vapor and liquid sorption, vapor diffusion, and first-order biodegradation was developed to describe the movement of volatile solute in unsaturated soils. Modeling studies were followed with laboratory batch and column studies on fine-grained soil samples obtained from a gasoline-contaminated site. Batch experiments yielded the sorption and diffusion coefficients for generating theoretical solute transport profiles. Column studies were conducted to examine toluene sorption, diffusion, and biodegradation under aerobic and denitrifying conditions. Results from the column studies indicated that vapor sorption onto the soil was minimal due to the high moisture content of the soil. Comparison of model predictions with experimental results indicated that the SASK model, which is based on the resistivity theory, provided a more accurate prediction of the vapor phase tortuosity than the frequently used Millington-Quirk equation. Laboratory results of toluene concentration profiles matched well with the model predictions and yielded degradation rates comparable to those obtained in the field. Column studies, examining toluene biodegradation under aerobic and denitrifying conditions in low-permeability soils, indicated that the presence of excess nitrate in aerobic environments yielded higher solute degradation rates than those observed under exclusively aerobic systems.

• Sponsoring Organization: USDOE
• OSTI ID: 290207
• Journal Information: Ground Water Monitoring and Remediation, Journal Name: Ground Water Monitoring and Remediation Journal Issue: 1 Vol. 18; ISSN 1069-3629; ISSN GWMREV
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
BIODEGRADATION
ENVIRONMENTAL TRANSPORT
MATHEMATICAL MODELS
REMEDIAL ACTION
SOILS
TOLUENE