Volatilization is the loss of chemicals in vapor form from the soil water (liquid phase) or the soil surfaces (solid phase) to the soil air (gas phase) of the unsaturated zone. Only the first type of volatilization, from the liquid phase to the gas phase, is discussed in this section. The volatilization from the solid phase to the gas phase is relatively small and usually neglected. However, information on this type of volatilization is presented by Mayer, Letey, and Farmer (1974); Baker and Mackay (1985); and Jury, Farmer, and Spencer (1984).

The extent of volatilization of an organic chemical from water to the soil air can be determined by Henry's law which states that when a solution becomes dilute, the vapor pressure of a chemical is proportional to its concentration (Thomas 1982) as

0 0

Post a comment