Mass transfer from nonaqueous phase organic liquids in water-saturated porous media

Journal Article · Wed Mar 31 23:00:00 EST 1993 · Water Resources Research; (United States)

DOI:https://doi.org/10.1029/92WR02581· OSTI ID:6148573

Geller, J T ^[1]; Hunt, J R ^[2]

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1. Lawrence Berkeley Lab., CA (United States)
2. Univ. of California, Berkeley (United States)

The widespread production and use of industrial solvents and liquid petroleum products have provided ample opportunity for subsurface contamination from leaking underground storage tanks and pipelines, hazardous waste sites, and surface spills. The aqueous solubility of these organic liquid contaminants is low enough for them to exist in the subsurface as nonaqueous phase liquids (NAPLs) but large enough to seriously degrade water quality. In this paper, results from measuring the complete dissolution of trapped NAPLs and developing a model are discussed. The NAPL saturation is modeled as discrete spheres that are initially uniform in size. From the experimental data, ganglia size and the cross-sectional area of the NAPL region are obtained by fitting the model to the data and assuming a fixed initial NAPL saturation. This two-parameter model, when combined with known magnitudes of residual saturation and relative permeability functions represented experimental observations of (1) increasing aqueous concentration during initial water flooding as the mass transfer zone is established, (2) a quasi-steady effluent concentration as the mass transfer zone propagates downstream, and (3) the decline in effluent concentration as the NAPL-containing region shrinks to less than the length of the mass transfer zone. The experimental data and modeling effort illustrate mechanisms that limit the remediation of NAPL-contaminated aquifers. There is a complex dependency of groundwater contaminant concentration on flow velocity.

• OSTI ID: 6148573
• Journal Information: Water Resources Research; (United States), Journal Name: Water Resources Research; (United States) Vol. 29:4; ISSN WRERAQ; ISSN 0043-1397
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540320* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (1990-)
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
AQUIFERS
CONTAINERS
CONTAMINATION
DATA
ENVIRONMENTAL QUALITY
EXPERIMENTAL DATA
FLOW MODELS
GROUND WATER
HAZARDOUS MATERIALS
HYDROGEN COMPOUNDS
INFORMATION
MASS TRANSFER
MATERIALS
MATHEMATICAL MODELS
NUMERICAL DATA
OXYGEN COMPOUNDS
PERMEABILITY
PETROLEUM PRODUCTS
PIPELINES
SATURATION
SOLUBILITY
SOLVENTS
STORAGE
TANKS
UNDERGROUND STORAGE
WATER
WATER QUALITY