A screening model for simulating DNAPL flow and transport in porous media: theoretical development
In the last two decades there has been an increased awareness of the contamination of groundwater due to the presence of denser-than-water nonaqueous phase liquids (DNAPLs). Numerous theoretical, experimental and numerical investigations have been conducted to study the various processes that impact aquifer contamination. These studies have provided us with greater insight into the individual processes and the complex nature of the problem. In spite of this progress, there still exists a need within the environmental community for a simple tool that will allow us to analyze a DNAPL contamination scenario from free-product release to transport of soluble constituents to downgradient receptor wells. Such a model may be useful in source term characterization for DNAPL releases to groundwater. The objective of this manuscript is to present the conceptual model and formulate the equations and modules which are utilized in this screening model. Three hypothetical releases are simulated and the results discussed to demonstrate the application and usefulness of this model. Due to its simplicity and ease of use, this screening model will be useful to industry, regulatory agencies and educators for estimating the impact of a DNAPL release on an aquifer.
screening model multiphase flow contaminant transport