The UZT: Unsaturated-Zone Transport package (MT3D-USGS) pane is is on the MODFLOW Packages and Programs dialog box under MT3DMS or MT3D-USGS. It is used to specify some of the data for the UZT package in MT3D-USGS. The UZT package is not included with MT3DMS. The Unsaturated-Zone Flow Transport Package in MT3D-USGS can only be used if the groundwater flow model is a MODFLOW-NWT model.
The comments can be used to record any information. The comments will be included at the beginning of the UZT package input file.
