NAPL Pool Dissolution in Stratified and Anisotropic Porous Formations
Publication: Journal of Environmental Engineering
Volume 124, Issue 9
Abstract
A two-dimensional numerical model is developed to study contaminant transport resulting from the dissolution of single- and multicomponent dense nonaqueous-phase liquid (DNAPL) pools in heterogeneous porous media. The aqueous-phase concentration of each dissolved component is assumed to undergo first-order decay as well as sorb under local equilibrium conditions. Pool shrinkage is accounted for by modeling the progressive reduction of the DNAPL pool surface area as a time-dependent boundary. Multicomponent pool dissolution is modeled using an effective solubility (or equilibrium aqueous solubility) relationship, where the nonaqueous-phase activity coefficient for each constituent is evaluated at each and every time step. Subsurface heterogeneities are depicted by an ideally stratified porous formation and by a statistically anisotropic aquifer. In the stratified formation, a multicomponent DNAPL pool is assumed to be formed at the interface between a sand layer and a clay layer, where DNAPL dissolution occurs simultaneously in both strata. The ground-water velocity inside the sand stratum is uniform in the longitudinal direction whereas the interstitial liquid in the aquitard is stagnant. In the statistically anisotropic aquifer, a single-component DNAPL pool is assumed to be formed on top of an impermeable bedrock, where DNAPL dissolution occurs in the aquifer only. Results from several model simulations indicate that dissolved contaminant concentrations in aquifers are reduced significantly in the presence of aquitards, and most importantly, the transfer of dissolved contaminants along the pool-water interface is slower within statistically anisotropic than within homogeneous aquifers.
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References
1.
Anderson, M. R., Johnson, R. L., and Pankow, J. F.(1992). “Dissolution of dense chlorinated solvents into groundwater, 3, modeling contaminant plumes from fingers and pools of solvent.”Envir. Sci. and Technol., 26(5), 901–908.
2.
Ang, A. H.-S., and Tang, W. H. (1975). Probability concepts in engineering planning and design, volume I—basic principles. Wiley, New York, N.Y.
3.
Ball, W. P., and Roberts, P. V.(1991). “Long-term sorption of halogenated organic chemicals by aquifer material, 1, equilibrium.”Envir. Sci. and Technol., 25(7), 1223–1237.
4.
Banerjee, S.(1984). “Solubility of organic mixtures in water.”Envir. Sci. and Technol., 18(8), 587–591.
5.
Bear, J. (1979). Hydraulics of groundwater. McGraw-Hill, Inc., New York, N.Y.
6.
BRI. (1993). PC-UNIFAC-4.0. BRI, Atlanta, Ga.
7.
Broholm, K., and Feenstra, S.(1995). “Laboratory measurements of the aqueous solubility of mixtures of chlorinated solvents.”Envir. Toxicol. and Chem., 14, 9–15.
8.
Burr, D. T., Sudicky, E. A., and Naff, R. L.(1994). “Nonreactive and reactive solute transport in three-dimensional heterogeneous porous media: Mean displacement, plume spreading, and uncertainty.”Water Resour. Res., 30(3), 791–815.
9.
Chrysikopoulos, C. V.(1995). “Three-dimensional analytical models of contaminant transport from nonaqueous phase liquid pool dissolution in saturated subsurface formations.”Water Resour. Res., 31(4), 1137–1145.
10.
Chrysikopoulos, C. V., and Lee, K. Y. (1998). “Contaminant transport resulting from multicomponent nonaqueous phase liquid pool dissolution in three-dimensional subsurface formations.”J. Contaminant Hydr., 31(1-2), 1–21.
11.
Chrysikopoulos, C. V., Voudrias, E. A., and Fyrillas, M. M.(1994). “Modeling of contaminant transport resulting from dissolution of nonaqueous phase liquid pools in saturated porous media.”Transp. in Porous Media, 16(2), 125–145.
12.
Dagan, G. (1989). Flow and transport in porous formations. Springer-Verlag, New York, N.Y.
13.
de Marsily, G. (1986). Quantitative hydrogeology, groundwater hydrology for engineers. Academic Press, San Diego, Calif.
14.
Fredenslund, A., Gmehling, J., and Rasmussen, P. (1977). Vapor-liquid equilibria using UNIFAC. Elsevier, New York, N.Y.
15.
Freeze, R. A.(1975). “A stochastic-conceptual analysis of one-dimensional groundwater flow in nonuniform homogeneous media.”Water Resour. Res., 11(5), 725–741.
16.
Gelhar, L. W. (1993). Stochastic subsurface hydrology. Prentice-Hall, Inc., Englewood Cliffs, N.J.
17.
Gelhar, L. W., and Axness, C. L.(1983). “Three-dimensional stochastic analysis of macrodispersion in aquifers.”Water Resour. Res., 19(1), 161–180.
18.
Gutjahr, A. L. (1989). “Fast Fourier transform for random field generation.”Proj. Rep. Contract No. 4-R58-2690R, for Los Alamos Grant, New Mexico Institute of Mining and Technology, Socorro, N.M.
19.
Hashimoto, I., Deshpande, K. B., and Thomas, H. C.(1964). “Peclet numbers and retardation factors for ion exchange columns.”Industrial and Engrg. Chem. Fundamentals, 3(3), 213–218.
20.
Hayduk, W., and Laudie, H.(1974). “Prediction of diffusion coefficients for nonelectrolytes in dilute aqueous solutions.”AIChE J., 20(3), 611–615.
21.
Holman, H.-Y. N., and Javandel, I. (1996). “Evaluation of transient dissolution of slightly water-soluble compounds from a light nonaqueous phase liquid pool.”Water Resour. Res., 32(4), 915–923. [Correction (1996). Water Resources Research, 32, 1917.]
22.
Incropera, F. P., and DeWitt, D. P. (1990). Fundamentals of heat and mass transfer, 3rd Ed., Wiley, New York, N.Y.
23.
Johnson, R. L., and Pankow, J. F.(1992). “Dissolution of dense chlorinated solvents into groundwater, 2, source functions for pools of solvent.”Envir. Sci. and Technol., 26(5), 896–901.
24.
Karickhoff, S. W.(1984). “Organic pollutant sorption in aquatic systems.”J. Hydr. Engrg., ASCE, 110(6), 707–735.
25.
Lee, K. Y., and Chrysikopoulos, C. V.(1995). “Numerical modeling of three-dimensional contaminant migration from dissolution of multicomponent NAPL pools in saturated porous media.”Envir. Geol., 26(3), 157–165.
26.
Lyman, W. J., Reehl, W. F., and Rosenblatt, D. H. (1982). Handbook of chemical property estimation methods. McGraw-Hill, Inc., New York, N.Y.
27.
Mackay, D., Shiu, W. Y., and Ma, K. C. (1992). Illustrated handbook of physical-chemical properties and environmental fate for organic chemicals, Vol. 3, volatile organic chemicals. Lewis Publishers, Chelsea, Mich.
28.
Mackay, D. M., Roberts, P. V., and Cherry, J. A.(1985). “Transport of organic contaminants in groundwater.”Envir. Sci. and Technol., 19(5), 384–392.
29.
Manivannan, I., Powers, S. E., and Curry, G. W. Jr. (1996). “Dissolution of NAPLs entrapped in heterogeneous porous media.”Non-aqueous phase liquids (NAPLs) in subsurface environment: Assessment and remediation, L. N. Reddi, ed., American Society of Civil Engineers, New York, N.Y., 563–574.
30.
Mason, A. R., and Kueper, B. H.(1996). “Numerical simulation of surfactant-enhanced solubilization of pooled DNAPL.”Envir. Sci. and Technol., 30, 3205–3215.
31.
Mercer, J. W., Skipp, D. C., Giffin, D., and Ross, R. R. (1990). “Basics of pump-and-treat groundwater remediation technology.”Rep. No. EPA-600/8-90/003, Robert S. Kerr Environmental Research Laboratory, Ada, Okla.
32.
Myrand, D., Gillham, R. W., Sudicky, E. A., O'Hannesin, S. F., and Johnson, R. L.(1992). “Diffusion of volatile organic compounds in natural clay deposits: Laboratory tests.”J. Contaminant Hydro., 10(2), 159–177.
33.
Russo, D., Zaidel, J., and Laufer, A.(1994). “Stochastic analysis of solute transport in partially saturated heterogeneous soil, 1, numerical experiments.”Water Resour. Res., 30(3), 769–779.
34.
Schwarzenbach, R. P., Gschwend, P. M., and Imboden, D. M. (1993). Environmental organic chemistry. Wiley, New York, N.Y.
35.
Seagren, E. A., Rittman, B. E., and Valocchi, A. J.(1994). “Quantitative evaluation of the enhancement of NAPL-pool dissolution by flushing and biodegradation.”Envir. Sci. and Technol., 28, 833–839.
36.
Stumm, W., and Morgan, J. J. (1981). Aquatic chemistry, 2nd Ed., Wiley, New York, N.Y.
37.
Sudicky, E. A.(1986). “A natural gradient experiment on solute transport in a sand aquifer: Spatial variability of hydraulic conductivity and its role in the dispersion process.”Water Resour. Res., 22(13), 2069–2082.
38.
Voudrias, E. A., and Yeh, M. F.(1994). “Dissolution of a toluene pool under constant and variable hydraulic gradients with implications for aquifer remediation.”Groundwater, 32(2), 305–311.
39.
Whelan, M. P., Voudrias, E. A., and Pearce, A.(1994). “DNAPL pool dissolution in saturated porous media: Procedure development and preliminary results.”J. Contaminant Hydrol., 15(3), 223–237.
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Copyright © 1998 American Society of Civil Engineers.
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Published online: Sep 1, 1998
Published in print: Sep 1998
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