As hazardous wastewater resides in surface impoundments, volatile organic chemicals (VOC's) enter the air phase. Under turbulence enhanced environmental conditions, significant amounts of dangerous chemicals can be released into the atmosphere in a short period of time.
Accurate predictions of the VOC emission rate from surface impoundments are necessary to develop appropriate regulations for the control of such emissions and to assess the potential threat to the public. Although the Two-Resistance Theory [ I ] has been found to be a sufficient quantitative tool to describe interphase desorption of VOC's from a surface impoundment, the method requires the estimation of up to six individual gas and liquid film coefficients, in addition to a Henry's Law Constant for the chemical of concern.
The Two Resistance Theory for a batch operated, hazardous wastewater impoundment is given by Equations 1, 2, and 3. l/KL (9 = l/kL(9 + l/k&m forced convention zone (1) l/KL ("'9 = l/kL ("9 + l/k#"j)rn zone of influence (2) l/KL (n) + l/kL ( n ) + l/kc,%n natural convention zone (3) Successful application of the theory to a surface impoundment re uires recognition of the existence of a operating surface aerator, a "zone of influence" in the proximity of the aerator, and a "natural zone" in which the mass transfer rate is determined by environmental condi-Large Edd 5 . k,, = 1.46 {-$$ (2)1r']"2 Mod/]