PUBLICATIONS - Techniques of Water-Resources Investigations, manual "A digital model for aquifer evaluation" by George F. Pinder.


               UNITED STATES DEPARTMENT OF THE INTERIOR
                          GEOLOGICAL SURVEY
                      WATER RESOURCES DIVISION
                      WASHINGTON, D. C.  20242

                                                  July 30, 1969
                                                      4037 0001

GROUND WATER BRANCH TECHNICAL MEMORANDUM NO. 70.3

To:       Regional Hydrologists and District Chiefs, WRD

From:     Chief, Ground Water Branch, WRD

Subject:  PUBLICATIONS - Techniques of Water-Resources
                         Investigations, manual "A digital
                         model for aquifer evaluation" by
                         George F. Pinder.

The subject TWRI manual chapter is now in progress of publication,
but it will not be available for distribution for several months.
In the interim a limited number of duplicated copies can be
furnished on request.

The program, which is written in FORTRAN IV for the IBM 360
system, provides a digital computer aquifer model for arrays of
data up to 48 x 65 nodes.  Recharge and discharge boundaries,
variations in transmissivity and storage coefficient, vertical
leakage, and nodal location of pumpage can be accommodated by the
model.  Expansion of the array is easily accomplished, if
equipment large enough and fast enough to handle the problem is
available.



                                   (s) C. L. McGuinness

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