Methods for Determining Inputs to Environmental Petroleum Hydrocarbon Mobility and Recovery Models This publication is an invaluable reference for operators, consultants and regulators responsible for cleanup of subsurface petroleum releases. Important fluid and soil property pa rameters are explained. Methods to measure each parameter are presented in order of re levance for use in environmental free - product mobility/recovery assessments. Fluid property parameters covered include density, viscosity, surface tension, and interfacial tension. Laboratory - scale soil property parameters include: capillary pressure vs. saturation, relative permeability vs. saturation, water and nonaqueous phase liquid saturation, and Brooks - Corey and van Genuchten model parameters. Field - scale bail - down and production test s are explained and cited. Sample collection and handling procedures are su mmarized. A listing and abstract of relevant ASTM methods are provided in the appendix