DNAPL MIGRATION THROUGH A FRACTURED PERCHING LAYER

The migration of a DNAPL (TCA) was demonstrated by a laboratory flow v isualization experiment. The system consists of two unconfined aquifer s separated by a siltstone perching layer containing a single fracture that conducts water flow downward, The TCA migrated along a tortuous path in the upper sandy aquifer and moved rapidly through the fracture . We observed no DNAPL pooling above the fracture prior to its entry i nto the fracture, in contrast to existing mathematical solutions of hy drostatic initial conditions and full saturation below the fracture. A multiphase flow model predicted the experimentally observed mean beha vior.