PUBLICATIONS--Report, "Derivation of equations describing solute transport in ground water,"

                           UNITED STATES
                    DEPARTMENT OF THE INTERIOR
                         GEOLOGICAL SURVEY
                      RESTON, VIRGINIA  22092

                                                      GW Branch

                                              December 29, 1977
                                                Code: 4060 0001



Subject:     PUBLICATIONS--Report, "Derivation of equations
                           describing solute transport in ground
                           water," by Leonard F. Konikow and
                           David B. Grove, WRI 77-19

Increased attention in recent years to problems of ground-water
contamination has stimulated the development of methods useful to
the understanding and quantitative description of the physical and
chemical processes that control the transport of solutes in ground
water.  The principal interest in these methodologies is the
ability to predict the rate and directions of movement of
contaminants from either existing or potential sources.

A solute transport model requires the solution of both the
equation describing flow and the equation describing the transport
and dispersion of reacting dissolved chemicals in a ground-water
system.  Because of the complexity of real-world aquifer systems,
the solution of these equations requires the use of numerical
approximating techniques.  Solute-transport models utilized at
present in WRD employ either finite-difference methods, finite-
element methods, the method of characteristics, or some
combination of these methods.  The selection of the "best" model
to use is largely problem-dependent.

Familiarity with and understanding of the equations is basic to
the use of any solute transport model.  The enclosed report by
Konikow and Grove gives a detailed, step-by-step derivation of a
general form of the solute transport equation.  The report shows
how the general equation can be modified or simplified for
application to a variety of field problems.  The derivation is
presented in a manner intended to stress understanding, more so
than mathematical rigor, of the reasoning and/or assumptions
leading to each step.  Although other derivations of the transport
equation are in the published literature, we believe that the
manner of development of this derivation makes it a good
introduction to quantitative modeling of solute-transport
processes in ground water.

Limited additional copies of the report are available on request
to the Ground Water Branch.

                              (s) Charles A. Appel
                              (for) Chief, Ground Water Branch


WRD Distribution:  A(memo only), B-Limited(w/encl.), FO-LS