Groundwater pollution by organic compounds: a two-dimensional analysis of contaminant transport in stratified porous media with multiple sources of non-equilibrium partitioning

• Published in: International journal for numerical and analytical methods in geomechanics 1999-12, Vol.23 (14), p.1717-1732
• Main Authors: Elzein, Abbas H., Booker, John R.
• Format: Article
• Language: English
• Subjects: Applied sciences; boundary element method; Buildings. Public works; Computation methods. Tables. Charts; contaminant migration; diffusion advection; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Geotechnics; Green's functions; Miscellaneous; non-equilibrium sorption; Pollution, environment geology; porous media; Structural analysis. Stresses
• ISSN: 0363-9061; 1096-9853
• DOI: 10.1002/(SICI)1096-9853(19991210)23:14<1717::AID-NAG991>3.0.CO;2-E

Transport of pollutants in soil and groundwater often occurs in stratified media under non‐equilibrium conditions. Confined aquifers are usually bounded by low‐permeability layers of soil which have been shown to exert a significant influence on the fate of contaminants in groundwater. Numerical solutions of transport equations have usually been restricted to single layers and have included single sources of non‐equilibrium processes or none at all. The effect of soil stratification itself has sometimes been reduced to a transport‐based non‐equilibrium process. A boundary element solution of the transport equations in the Laplace domain is extended to include multiple sources of non‐equilibrium processes in saturated media under the assumption of rate‐limited mass transfer. Green functions accurately model infinite and semi‐infinite domains such as soils and Laplace transforms remove the need for time‐stepping and the associated numerical complexity. The proposed numerical technique is validated by comparing its results to analytical solutions. Its scope is illustrated through a case study of a sand aquifer bounded by less permeable layers of silt, and infiltrated by pollutants from a neighbouring lake. Copyright © 1999 John Wiley & Sons, Ltd.