Hydrocarbon spills impact drinking water supplies at down gradient locations. Conventional finite difference and finite element models of multiphase, multicomponent flow have extreme requirements for both computer time and site data. Site data and the intent of the modeling often do not warrant the application of such models. An alternative approach is proposed which is based on semi-analytic models for vertical product infiltration, radial spreading on the water table, and transport of aqueous phase contaminants in the aquifer. Three individual models for these processes are linked to estimate exposure at a down gradient well. A time record of concentration can be determined for any desired location in the aquifer. The presentation outlines the methodology and examines parameter sensitivity within the combined vadose zone, oil lens, and aquifer transport models.

Bibliography: p. 246-47.