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The "dye" constituent may also be used as an "age of water" function to compute residence times and visualize domain/boundary water mixing if this option is selected. This option is available in EFDC_DSI EFDCPlus only.
See Apply Cell Properties via Polygons as to how to apply cell properties via polygons with the Dye button in the Initial Conditions frame.
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If using the restart option, the user can initialize a dye field using the DYE.INP file by selecting the Dye Overwrite check box on the Initial tab, located in the EFDC Restart Option frame.