Field investigations nationwide reveal the presence of nonaqueous phase liquids in the subsurface. Oily fuels have been released to the subsurface by leaky tanks, while at other sites, contamination has resulted from chemical spills and improper waste disposal practices. Due to the complexities of multiphase flow and transport processes, researchers have only recently begun to develop simulation models. To gain a better understanding of the contaminant migration and fate, a comprehensive multiphase simulator is needed. Currently available simulators are limited in applications. Many simulators require unrealistic modeling assumptions. Others are capable of modeling the complex subsurface processes but restricted by excessive computational demands and thus impractical for use'on site-specific problem I s. Researchers are developing a versatile simulator suitable for field and research applications. A general non-isothennal compositional formulation allowing chemical transport in all phases is being used. The model incorporates state-of-the-art numerical schemes and various options for considering simplifying assumptions to provide efficient solutions for a wide variety of practical problems. The model is being developed by extending an existing multiphase code to include compositional and non-isothermal effects. The enhancpd code is verified against analytical solutions and other documented numerical codes.The potential commercial application as described by the awardee: The research would enable a comprehensive assessment and remedial evaluation of soil and groundwater contamination by petroleum and industrial chemicals. The product of the research will be of significant commercial interest to govemment agencies and industries.
