Volatilization (also referred to as vaporization or evaporation) is the conversion of a chemical from the solid or liquid phase to a gas or vapor phase.
The partitioning of a volatile compound in the subsurface environment comprises two distinct patterns: volatilization of contaminant molecules (from the liquid, solid, or adsorbed phase) and dispersion of the resulting vapors in the subsurface gas phase or the overlying atmosphere by diffusive
and turbulent mixing.
Even though the two processes are fundamentally different and controlled by different chemical and environmental factors, they are not wholly independent under natural conditions: only by integrating their effects can volatilization be characterized.