The MST: Mobile Storage and Transfer Package pane is used to activate the Mobile Storage and Trnasfer package. It is on the MODFLOW Packages and Programs dialog box under Groundwater Transport| | GWT: Groundwater Transport. The Mobile Storage and Trnasfer package is required.
FIRST ORDER DECAY—is a text keyword to indicate that first-order decay will occur. Use of this keyword requires that DECAY and DECAY SORBED (if sorption is active) are specified in the GRIDDATA block.
ZERO ORDER DECAY—is a text keyword to indicate that zero-order decay will occur. Use of this keyword requires that DECAY and DECAY SORBED (if sorption is active) are specified in the GRIDDATA block.
sorption—is a text keyword to indicate that sorption will be activated. Valid sorption options include LINEAR, FREUNDLICH, and LANGMUIR. If sorption is simulated in the IST package it must also be simulated in the MST package using the linear option.