Historical Development of Constitutive Relations for Addressing Subsurface LNAPL Contamination

An overview of the historical development of k-S-P relations (constitutive relations) to model potential flow of light nonaqueous phase liquids (LNAPLs) in the subsurface is presented in this chapter. The focus is advancements proposed by Parker, Lenhard, and colleagues over time. Discussion includes constitutive relations for incorporation in numerical multiphase flow models as well as constitutive relations for predicting subsurface LNAPL volumes and transmissivities from fluid levels measured in monitoring groundwater wells. LNAPL saturation distributions are given for various subsurface properties and layering sequences.