PROGRAMS AND PLANS--Establishment of a National Policy to Archive Ground-Water Flow and Transport Models

In Reply Refert To:                          October 28, 1992
Mail Stop 411


Subject:  PROGRAMS AND PLANS--Establishment of a National Policy
          to Archive Ground-Water Flow and Transport Models


Ground-water flow and transport models are an integral part of our interpretive
ground-water investigations, and the results of these models form the basis for
many of the conclusions published in U.S. Geological Survey reports.  The
numerical data and related information that comprise these models need to
remain available to:  (1) support and validate the results in published reports,

(2) assure that working versions of all models are available for future
scientific use, and (3) assure that the data are available to the public when
requested.  The appropriate model data and related information are to be stored
in a permanent, well- documented manner to ensure their continued availability.

Effective as of the date of this memorandum, a national ground- water model
archive is established.  All ground-water flow and transport models that are a
significant part of ground-water investigations with completion dates of
October 1993 or later are to be included in the archive.  Where feasible,
districts also should archive models from completed investigations and from
current projects to be completed prior to October 1993.  The Regional Ground
Water Specialists are to act on behalf of the Office of Ground Water to assure
that all required information is present in the archive.  Status of the
archives also will be examined as a routine part of district ground-water
discipline reviews.  Design and implementation requirements for the archive are
presented in Attachments 1 and 2 to this memorandum.

The archive is for internal Water Resources Division (WRD) access and use and
is to serve as the source of ground-water model data supplied to the public
upon request.  The public release of specific information contained in the
archive is subject to compliance with any existing WRD policies that may apply
to the public release of such information.

The ground-water model archive does not relieve individual investigators of the
need to fully describe and document model analyses in their reports.

                              Joseph S. Rosenshein
                              Acting Chief, Office
                                of Ground Water

2 Attachments

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

                        ATTACHMENT 1



The archive will consist of a main directory called GWMARCIV.  A report
subdirectory, located directly below GWMARCIV, will be established for each
published report containing a ground-water flow or transport model analysis.
Each report subdirectory should be given a name that clearly reflects the U.S.
Geological Survey report number.  The archive must include the model source
codes, input files, macros and operating files such as JCL, CPL, and UNIX shell
codes, and model output files for each simulation described in the report.
These simulations will include (when applicable) the final calibrated steady-
state and transient results and any predictive results described in the
publication. Model results of minor importance, such as interim calibration
runs, should not be archived.  Model output will be archived for future
verification that the input data files properly reproduce the published results
when the input files are rerun.  The storage of additional ancillary data is
optional, but is strongly encouraged.  Examples of ancillary data that might be
stored are pertinent pre- and post-processor codes, related data, or other
files directly related to the model simulations.

A subdirectory named CONTENTS, located immediately below each report directory,
will include one or more files that contain:

(1) the full reference for the subject report; (2) descriptions of the
subdirectory structure and of the files contained in each subdirectory, (3)
descriptions of data file formats, when appropriate; (4) the sequence of model
runs; and (5) instructions for running simulations.  Attachment 2 shows one
example of what an archive directory structure might look like for a typical

When the input data of one model depends directly on output from another model,
both models are to be included in the archive.  If the models are documented in
separate reports, a cross-reference between the reports must be included in the
CONTENTS directory of the archive entry for each report.

Model input files must be stored in ASCII format to assure that they can be
processed in the future on virtually any computer without the need for
specialized or proprietary software.  In cases where model input files are
derived from either proprietary or machine-dependent software, ASCII versions
of the model input files must be included in the archive.


Each district will set up an archive on a locally based computer.  The district
staff is responsible for designing a subdirectory structure that permits
efficient and logical storage of the required information for each specific
model.  Files will be accumulated and stored in the on-line archive until the
final interpretive report is approved, after which time the files are to be
moved to permanent storage.

For all studies with completion dates of October 1993 or later, the appropriate
model files must reside on-line in the district archive when the report is
submitted to the Region for approval.  Verification of compliance with this
policy is the responsibility of the Regional Ground Water Specialists.  Reports
returned to the district for revision that require new or additional model
simulations will require an archive update.

Upon final approval of the interpretive report, the archive is to be copied to
permanent storage on an optical disk using WORM (write once, read many)
technology.  A copy of the WORM disk will remain in the originating district to
service requests for data, and a duplicate copy will be furnished to the Region
for off-site backup.  A WORM disk may contain model data for one or more
published reports provided the disk is indexed appropriately.  The archive may
be transferred to tape as a short-term storage option if the district does not
have immediate access to WORM disk production equipment.  The period of interim
storage on tape should not exceed 1 year.  The archive process is considered
complete only when a WORM disk has been produced.  On-line storage of the
archived data may be discontinued at the discretion of the district following
transfer of the archive to WORM disk or to interim tape storage.