U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  5

                                                   PUBLICATION DATE:  05/30/1989
Station ID: 8720004                                SUPERCEDED DATE:   04/21/2003
Name:       CRANDALL, ST MARYS RIVER                          
            FLORIDA
NOAA Chart: 11502                                  Latitude:         30° 43.3' N
USGS Quad:  ST. MARYS                              Longitude:        81° 37.3' W


To reach the tidal bench marks from the intersection of U.S. Highway 17 and
State Highway A1A in Yulle, proceed 3.7 miles (6.0 km) north on Highway 17 to
its intersection with Crandall Road (dirt drive), then 3.6 miles (5.8 km) north
on Crandall Road to the Rayonier SE Timber Division Recreation Area on the south
bank of St Marys River.  The bench marks are in the recreation area.  The tide
gage and staff were on the wooden seawall of the recreation area.


                         T I D A L   B E N C H   M A R K S


                 PRIMARY BENCH MARK STAMPING:  0004 C 1977

MONUMENTATION:           Survey Disk                               VM#:     4970
AGENCY:                                                            PID#:  BC2423
SETTING CLASSIFICATION:  Copper-clad Steel Rod


The bench mark is 210 feet (64 m) SSW of the artesian well, 182.3 feet (55.6 m)
SSW of Bench Mark No 4 1952, 14 feet (4 m) NNE of the centerline of the dim
track path leading NW, and 0.5 foot (0.2 m) SSW of a witness post.  The bench
mark is 0.1 foot (0.03 m) below ground level, crimped to a copper-clad steel rod
driven 26 feet (8 m) to refusal, and encased in a PVC pipe and concrete
kickblock.



                         BENCH MARK STAMPING:  CRANDALL NO 3 1934

MONUMENTATION:           Survey Disk                               VM#:     4967
AGENCY:                                                            PID#:  BC2425
SETTING CLASSIFICATION:  Concrete Foundation


The bench mark is set in the top of a large, old concrete foundation at the NW
corner of the park, 172 feet (52 m) north of an artesian well, 73 feet (22 m)
east of the west end of a track road through the park, 24 feet (7 m) south of
the river bank, and 2 feet (1 m) above ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                   PUBLICATION DATE:  05/30/1989
Station ID: 8720004                                SUPERCEDED DATE:   04/21/2003
Name:       CRANDALL, ST MARYS RIVER                          
            FLORIDA
NOAA Chart: 11502                                  Latitude:         30° 43.3' N
USGS Quad:  ST. MARYS                              Longitude:        81° 37.3' W


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  NO 4 1952

MONUMENTATION:           Survey Disk                               VM#:     4968
AGENCY:                                                            PID#:  BC2424
SETTING CLASSIFICATION:  Concrete Monument


The bench mark is set in the top of a concrete monument, about 500 feet    (152
m) NNW of a sign designating the Rayonier SE Timber Division Recreation Area,
212 feet (65 m) SSW of Bench Mark CRANDALL NO 3 1934, 182.3 feet (55.6 m) NE of
Bench Mark 0004 C 1977, 58 feet (18 m) west of the centerline of the road, 45.5
feet (13.9 m) south of the artesian well, and 1 foot (0.3 m) ENE of a witness
post.



                         BENCH MARK STAMPING:  0004 B 1977

MONUMENTATION:           Survey Disk                               VM#:     4969
AGENCY:                                                            PID#:  BC2426
SETTING CLASSIFICATION:  Copper-clad Steel Rod


The bench mark is 400 feet (122 m) east of Bench Mark CRANDALL NO 3 1934, 331.2
feet (100.9 m) east of Bench Mark No 4 1952, 110 feet (34 m) NW of a concrete
picnic table, 9 feet (3 m) south of the river bank, and 3.8 feet (1.2 m) north
of a large oak tree with witness sign.  The bench mark is 0.3 foot (0.1 m) below
ground level, crimped to a copper-clad steel rod driven 37 feet (11 m) to
refusal, and encased in a PVC pipe and concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                   PUBLICATION DATE:  05/30/1989
Station ID: 8720004                                SUPERCEDED DATE:   04/21/2003
Name:       CRANDALL, ST MARYS RIVER                          
            FLORIDA
NOAA Chart: 11502                                  Latitude:         30° 43.3' N
USGS Quad:  ST. MARYS                              Longitude:        81° 37.3' W


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  0004 D 1977

MONUMENTATION:           Survey Disk                               VM#:     4971
AGENCY:                                                            PID#:  BC2422
SETTING CLASSIFICATION:  Copper-clad Steel Rod


The bench mark is 301 feet (92 m) SSE of Bench Mark 0004 C 1977, 58 feet    (18
m) NW of the centerline of the drive leading into the recreation area, 27.6 feet
(8.4 m) west of the fork in Crandall Road, 7.2 feet (2.2 m) north of the sign
designating the Rayonier SE Timber Division Recreation Area, and 0.5 foot (0.2
m) south of a witness post.  The bench mark is 0.2 foot (0.1 m) below ground
level, crimped to a copper-clad steel rod driven 48 feet (15 m), and encased in
a PVC pipe and concrete kickblock.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                   PUBLICATION DATE:  05/30/1989
Station ID: 8720004                                SUPERCEDED DATE:   04/21/2003
Name:       CRANDALL, ST MARYS RIVER                          
            FLORIDA
NOAA Chart: 11502                                  Latitude:         30° 43.3' N
USGS Quad:  ST. MARYS                              Longitude:        81° 37.3' W


                            T I D A L   D A T U M S 


Tidal datums at CRANDALL, ST MARYS RIVER based on:

     LENGTH OF SERIES:      4 MONTHS
     TIME PERIOD:           FEBRUARY-MAY 1978
     TIDAL EPOCH:           1960-1978
     CONTROL TIDE STATION:  8720030 FERNANDINA


Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:

     HIGHEST OBSERVED WATER LEVEL (02/09/1978)         =   6.50
     MEAN HIGHER HIGH WATER                     MHHW   =   5.33
     MEAN HIGH WATER                            MHW    =   5.07
     MEAN TIDE LEVEL                            MTL    =   2.64
     MEAN LOW WATER                             MLW    =   0.20
     MEAN LOWER LOW WATER                       MLLW   =   0.00
     LOWEST  OBSERVED WATER LEVEL (03/10/1978)         =  -1.40

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In FEET above:

     Stamping or Designation                    MLLW        MHW

     0004 C 1977                                14.89      9.82
     CRANDALL NO 3 1934                         13.62      8.55
     NO 4 1952                                  12.64      7.57
     0004 B 1977                                12.08      7.01
     0004 D 1977                                14.70      9.63


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  5

                                                   PUBLICATION DATE:  05/30/1989
Station ID: 8720004                                SUPERCEDED DATE:   04/21/2003
Name:       CRANDALL, ST MARYS RIVER                          
            FLORIDA
NOAA Chart: 11502                                  Latitude:         30° 43.3' N
USGS Quad:  ST. MARYS                              Longitude:        81° 37.3' W


                             D E F I N I T I O N S


Mean Sea Level (MSL) is a tidal datum determined over a 19-year National Tidal
Datum Epoch.  It pertains to local mean sea level and should not be confused
with the fixed datums of North American Vertical Datum of 1988 (NAVD88).

NAVD88 is a fixed datum derived from a simultaneous, least squares, minimum
constraint adjustment of Canadian/Mexican/United States leveling observations.
Local mean sea level observed at Father Point/Rimouski, Canada was held fixed as
the single initial constraint.  NAVD88 replaces NGVD29 as the national
standard geodetic reference for heights.  Bench mark elevations relative to
NAVD88 are available from NGS through the World Wide Web at 
National Geodetic Survey.

NGVD29 is a fixed datum adopted as a national standard geodetic reference for
heights but is now considered superseded.  NGVD29 is sometimes referred to as
Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological
Survey Topographic Quads.  NGVD29 was originally derived from a general
adjustment of the first-order leveling networks of the U.S. and Canada after
holding mean sea level observed at 26 long term tide stations as fixed.
Numerous local and wide-spread adjustments have been made since establishment in
1929.  Bench mark elevations relative to NGVD29 are available from the National
Geodetic Survey (NGS) data base via the World Wide Web at 
National Geodetic Survey.

NAVD88 and NGVD29 are fixed geodetic datums whose elevation relationships to
local MSL and other tidal datums may not be consistent from one location to
another.

The Vertical Mark Number (VM#) and PID# shown on the bench mark sheet are unique
identifiers for bench marks in the tidal and geodetic databases, respectively.
Each bench mark in either database has a single, unique VM# and/or PID# assigned.
Where both VM# and PID# are indicated, both tidal and geodetic elevations are
available for the bench mark listed.

The NAVD88 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have NAVD88 elevations.
The NAVD88 elevation relationship shown in the table is derived from an average
of several bench mark elevations relative to tide station datum.  As a result of
this averaging, NAVD88 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from NAVD88 elevations listed for
each bench mark in the NGS database.