연구의 선진화와 생산성 향상에
필요한 최적의 소프트웨어와 컨설팅을
공급하도록 노력하겠습니다.

Inorganic/Organic Toxics Interface

The EFDC code includes two internal submodels for simulating the transport and fate of toxic contaminants. Effectively, an unlimited number of toxic contaminants may be simulated.  A simple, single-contaminant submodel can be activated from the master input file. The simple model accounts for water and suspended sediment phase transport with equilibrium partitioning and a lumped first-order reaction. Contaminant mass per unit area in the sediment bed is also simulated. The second, more complex submodel simulates the transport and fate of an arbitrary number of reacting contaminants in the water and sediment phases of both the water column and sediment bed. In this mode, the contaminant transport and fate simulation is functionally similar to the WASP5 TOXIC model (Ambrose et al., 1993) with the added flexibility of simulating an arbitrary number of contaminants, and the improved accuracy of more complex three-dimensional physical transport fields in a highly accurate numerical-transport scheme. Water-sediment phase interaction may be represented by equilibrium or nonlinear sorption processes. In this mode, the multilayer sediment bed formulation is active, with sediment bed water volume and dissolved contaminant mass balances activated to allow contaminants to reenter the water column by both sediment resuspension, pore water expulsion due to consolidation, and diffusion from the pore water into the water column. The complex contaminant model activates a subroutine describing reaction processes with appropriate reaction parameters provided by a toxic reaction processes input file.


The toxic transport parameters and options are set using the form shown in below. Each toxic has many of its own settings so the user must first select the toxic to be edited/entered by using the drop down list in the upper left corner of the “Toxic Transport Parameters” frame. 


1


The “Initial Conditions and Other Parameters” tab is shown in below. From this tab the user may set the Sediment/Water Column Interface Pore Water Diffusion rate. 


2


The “Assignments” tab is shown below. The water column DOC may be set to constant or vary spatially, in which latter case the user should use the DOCW.INP file to assign the constant time - spatially varying DOC.


3