Influence of lens on migration of dense non-aqueous phase liquid in saturated zone

Abstract EN

This study concerns the control of movement of Dense Non-Aqueous Phase Liquid (DNAPL) in saturated zone in the presence of relatively low permeability lens.

A two-dimensional, finite-difference numerical model for the simultaneous movement of the DNAPL and water through the saturated zone of the soil is developed.

The system is, actually, a three fluid phase system (water, DNAPL and air) but in the derivation of the model, air was treated as an immobile phase at constant atmospheric pressure.

The flow equations for Dense Non-Aqueous Phase Liquid and water are cast in terms of the wetting and non-wetting fluid pressure heads respectively.

The finite- difference equations are solved fully implicitly using Newton-Raphson iteration scheme with a Taylor series expansion to treat the nonlinearity.

The present numerical results are compared with results of Kueper and Frind (1991b).

The results of all tests showed that the presence of lens controls the vertical movement of Dense Non-Aqueous Phase Liquid (DNAPL) in heterogeneous porous medium.