Release of report, "Simulation of solute transport in variably saturated porous media with supplemental information on modification to the U.S. Geological Survey's computer program VS2D,"


WGS-Mail Stop 411                                August 22, 1990


OFFICE OF GROUND WATER TECHNICAL MEMORANDUM NO. 90.07

SUBJECT:  PUBLICATIONS--Release of report, "Simulation of solute
                        transport in variably saturated porous
                        media with supplemental information on
                        modification to the U.S. Geological
                        Survey's computer program VS2D," by R. W.
                        Healy

The subject report has recently been published as Water-Resources
Investigations Report 90-4025.  The report describes and documents
the computer program, VS2DT, which has been developed and tested
for simulating solute transport in variably saturated porous
media.  The program is an extension to the U.S. Geological
Survey's computer program VS2D for simulating water movement
through variably saturated porous media.  The program allows the
following chemical processes to be simulated:  first-order decay
of the solute, equilibrium adsorption of solute to the solid phase
(as described by Freundlich or Langmuir isotherms), or ion
exchange.  The program VS2DT can simulate problems in one-
dimensional columns, two-dimensional vertical cross sections, or
axially symmetric, three-dimensional cylindrical geometries.  The
porous media may be heterogeneous and anisotropic but principal
directions of the hydraulic conductivity tensor must coincide with
coordinate axes.  The computer program is written in standard
FORTRAN77 and is modular in structure.  The report describes
modifications to the original version of VS2D that include a
provision for the x and z axes to be tilted.

We recommend that this information be brought to the attention of
personnel concerned with flow or solute transport in the
unsaturated zone.

One copy of the report is being sent under separate cover to all
District offices, State offices, and some Subdistricts.  Copies of
the computer program, VS2DT,  and a limited number of additional
copies of this report are available from the author.



                               Thomas E. Reilly
                               Acting Chief, Office
                               of Ground Water

WRD Distribution:  A, B, S, FO, PO