Modeling of Aircraft Deicing Fluid Induced Biochemical Oxygen Demand in Subsurface-Flow Constructed Treatment Wetlands

Aircraft deicing is vital to safe operation in cold weather environments. Unfortunately, release of glycol-based aircraft deicing fluids (ADF) to waterways adjacent to airfields poses a significant environmental threat. The deicing fluids used at DoD airfields impart a high biochemical oxygen demand (BOD) when they enter waterways. The currently accepted conventional treatment is collection and transport of ADF-laden storm water to a publicly owned treatment works. The volume and BOD concentrations in the storm water often make this type of treatment impractical. Subsurface flow constructed treatment wetlands have been demonstrated to be effective in attenuating ADF-induced BOD. The models currently used to design and model these types of wetlands focus on simple input-output relationships and do not take underlying processes into account. This study explores the use of a system dynamics modeling method as the basis for a useful design and management tool. The model focuses on simulating storm water flow between defined sections of the wetland and microbial kinetics in each section. Microbial utilization of substrates leads to attenuation in well designed wetlands.