4.5 Using Known Fluxes

For the pond/surface impoundment case, the known flux capabilities of the module can be applied to leaching, overland flow, and volatilization.  Known flux capabilities can be used in two ways for each pathway.  The first way to use known fluxes for leaching would be to pass known leaching flux rates to the groundwater transport code.  The second way would be to "turn leaching off" by inputting a known leaching flux of 0.  The same is true for the overland pathway and the volatilization pathway.  The volatilization pathway offers an additional method for adjusting flux.  An adjustment factor (called the volatization ratio) can be multiplied by [dM_i/dt]vol to reduce the volatization flux.  The overall treatment of mass loss in the source-term module does not change.  The known leach rate replaces the calculated value for [dM_i/dt]_leach, the known overland rate replaces the calculated [dM_i/dt]_over, and the known volatization rate replaces the calculated [dM_i/dt]_vol in Equation 4.4.  All other calculations are done identically to the calculated flux cases.