ABSTRACT
This chapter presents some of the field and laboratory techniques that are available for obtaining parameters that can be used in quantitative analyses and model simulations of vadose-zone processes. It addresses the portion of a vadose-zone characterization effort that is often critical to its success: planning. The chapter briefly outlines a five-step process that is usually relevant to planning most subsurface site investigations involving the vadose zone; however, the basic outline could apply to almost any hydrogeological investigation. The five-step process are: state the problem that requires solution; develop a preliminary conceptual model of the system; identify an approach to address the problem; identify the data needed to solve the problem; and develop a site characterization work plan. The chapter discusses hydraulic properties of the vadose zone. The principal properties include saturated hydraulic conductivity, unsaturated hydraulic conductivity, air permeability, and specific water capacity.
