Via Calculation 
Mass transport computation the following input window appears:
When calling the module, the program reads the batch file with the default name (here: sitra.bsi).
Iteration of thickness (2D) / partially saturated computation (3D)
This part is related to the iteration of the thickness in a 2D horizontal model or the partially saturated computation of the free surface in vertical or 3D models. The user must decide whether the iteration is performed. Furthermore, the maximum number of iterations and the attenuation factor must be defined. If a calculation has already taken place, it is possible to continue the iteration.
In a transient calculation of 2D horizontal models, the number of iterations and the attenuation factor are set to "1", the selection fields are disabled. In an inverse model calculation, the number of iterations is generally set to "1", the attenuation factor can be entered (except for 2-D horizontal models).
Considering confined/unconfined conditions
This checkbox appears only in a 2D horizontal model with a thickness limited through the attributes OBER or UNDU. If there are confined conditions, they can be taken into account in the calculation of the storage coefficient by checking the checkbox. Otherwise, the storage coefficient is determined for unconfined conditions (see chapter: "Computation of the storage coefficient").
Status of flow and transport
Here the choice is made whether flow and transport are calculated steady state or transient. If the mass transfer is steady state, a calculation with adsorption or production and decay is not possible.
Transient input file
Selecting the file with the transient data (file selection box)
Time steps
An explanation of the defined time steps is already given in chapter „ Compilation of different model types – creating a transport model“ .
The buttons at the top of the input window allow resetting the input parameters (
), opening an existing batch file (
) or saving the current batch file under another name (
).