README FILE FOR LMT7 for MODFLOW-2005
[Version 7.0: 08/08/2008]

INTRODUCTION

LMT7 is a new package for MODFLOW-2005 that enables it to produce 
the information needed by MT3DMS for multi-species mass transport 
modeling.  The LMT7 Package is modified from a previous version 
LMT6 for MODFLOW-2000, as documented in the USGS Open-File 
Report 01-82 (Zheng and others, 2001), available from
http://water.usgs.gov/nrp/gwsoftware/modflow2000/ofr01-82.pdf.  


REVISION HISTORY

Version 7.0: 08-08-2008
-----------------------
Initial release.


Notes on the LMT Input File for MODFLOW
=======================================

The data in the MODFLOW input file for LMT7 are the same as for the
original LMT6 version of LMT (see above Internet link to
the documentation for LMT6). The LMT7 input file must have the
following records:

OUTPUT_FILE_NAME    [***.FTL]
OUTPUT_FILE_UNIT    [333]
OUTPUT_FILE_HEADER  [extended]
OUTPUT_FILE_FORMAT  [unformatted]

The first item in each line is a keyword (shown in all uppercase) that
must be specified exactly as shown except that either uppercase or
lowercase can be used. The 2nd item in each line is shown in brackets,
which indicates the items are optional. If an optional item is specified,
do not include the brackets.  When any of the optional items are omitted,
default values as shown above are assigned. Note that the placeholder [***]
is replaced by the same root name of the LMT input file.

The MODFLOW Name File must include the name of an LMT input file to 
activate the LMT7 package and cause MODFLOW to create the flow-transport
link file used by MT3DMS.  The file type in the Name file must be LMT6.
This file type for the LMT7 package is unchanged from that used for the
LMT6 package because the input file is unchanged.  Commonly, a file
extension of ".LMT" is used for the input file.  The following is a
sample LMT line in the MODFLOW Name File for a file named "test.lmt".

LMT6   45  test.lmt

The second item is an unused file unit that MODFLOW will use to read the
LMT input file.  In this example, 45 is used for the unit number.


Notes on the Implementation of LMT7 in MODFLOW-2005
===================================================

The source code for the LMT7 package includes two Fortran files, 
lmt7.inc and lmt7.f.  To implement LMT7 in MODFLOW-2005, do the
following:

a) Insert the keyword 'LMT6' (all capital) in the 49th element 
   of the CUNIT array in the MODFLOW-2005 main program;
b) Add this statement [include 'lmt7.inc'] in the MODFLOW-2005
   main program immediately after all the calls to the various
   budget subroutines; and
c) Put the LMT source files lmt7.inc and lmt7.f together with 
   other MODFLOW-2005 source files and recompile.


Notes on the Flow-Transport Link File
=====================================

The flow-transport link file produced by MODFLOW-2005 through the 
LMT7 package can be saved in either an unformatted (binary) file 
or an ASCII text file with free format.  The former can be read by 
all versions of MT3DMS while the latter only by MT3DMS version 4.0 
or later.  Because an ASCII text file requires much more disk space 
than an equivalent unformatted (binary) file, the ASCII text file option 
is intended mainly for debugging purposes when the unformatted (binary) 
option fails to work properly.

The structure of unformatted (binary) files used in MODFLOW-2005 is 
controlled by a number of "specifiers" in the file 'openspec.inc' 
as part of MODFLOW-2005 distribution files.  These specifiers are 
used in the OPEN statement to open the flow-transport link file along 
with other input/output files.  If non-standard specifiers are used, 
such as FORM = 'BINARY', it may be necessary to use the same 
OPEN statement specifiers in the MT3DMS code for the 
flow-transport link file to be read by MT3DMS correctly.  For MT3DMS 
version 4.0 or later, the structure of unformatted files is specified 
in the source file 'filespec.inc', similar to 'openspec.inc' used by 
MODFLOW-2005. 

MODFLOW Internal Flow and Sink/Source Packages Supported in LMT
===============================================================
LMT7 supports the following MODFLOW Internal Flow and Sink/Source
Packages: BCF7, LPF7, HUF7; RIV7, RCH7, WEL7, DRN7, EVT7, GHB7, STR7,
RES7, FHB7, MNW, ETS7, and DRT7.