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

                                                                                
Station ID: 8664662                         PUBLICATION DATE:  02/05/2004
Name:       ARMY DEPOT, COOPER RIVER                          
            SC
NOAA Chart: 11527                           Latitude:   32° 54.6' N (  32.91000)
USGS Quad:  NORTH CHARLESTON                Longitude:  79° 57.1' W ( -79.95170)


To reach the tidal bench marks from the intersection of U.S. Highway 52 (Rivers
Avenue) and Remount Road in North Charleston, proceed east on Remount Road for
4.3 km (2.7 mi) to the entrance to U.S. Army Charleston Storage Activity
(TROSCOM), then turn left and go north through the guard gate on Virginia Avenue
to Avenue A, then turn right and proceed east on Avenue A for 1.0 km (0.6 mi) to
Perimeter Road, then turn right and proceed on Perimeter Road for 0.3 km (0.2
mi) to Dock Road, then turn left  and proceed east on Dock Road for 1.0 km (0.6
mi) to Basin Road, then turn left and proceed NE onto Basin Road to the Goose
Creek wood pier just past the sharp bend in the road.  The bench marks are along
Basin Street and in the area around the concrete pier.  The tide gage and staff
were on the west end of the Goose Creek wood pier.


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


                 PRIMARY BENCH MARK STAMPING:  CREEK 1976
                         DESIGNATION:          CREEK

MONUMENTATION:           Survey disk                           VM#:         4082
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  CJ1477
SETTING CLASSIFICATION:  Concrete pier                         OPUS PID#: CJ1477
LATITUDE:   32° 54.5' N (  32.90830)          LONGITUDE:  79° 57.1' W ( -79.95170)


The primary bench mark is a disk set flush in the NE end of the concrete pier,
12.22 m (40.1 ft) south of the NW edge of the pier, 3.57 m (11.7 ft) south of
fire hydrant #855, 1.83 m (6.0 ft) north of the NE edge of the pier, and 0.43 m
(1.4 ft) SE of the SE railroad track.

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

                                                                                
Station ID: 8664662                         PUBLICATION DATE:  02/05/2004
Name:       ARMY DEPOT, COOPER RIVER                          
            SC
NOAA Chart: 11527                           Latitude:   32° 54.6' N (  32.91000)
USGS Quad:  NORTH CHARLESTON                Longitude:  79° 57.1' W ( -79.95170)


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


                         BENCH MARK STAMPING:  NO 4 1942
                         DESIGNATION:          866 4662 TIDAL 4

MONUMENTATION:           Tidal Station disk                    VM#:         4080
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  CJ0217
SETTING CLASSIFICATION:  Concrete pier                         OPUS PID:        
LATITUDE:   32° 54.4' N (  32.90670)          LONGITUDE:  79° 57.3' W ( -79.95500)


The bench mark is a disk set flush in the SW end of the concrete pier, 12.65 m
(41.5 ft) SE of a light pole, 1.22 m (4.0 ft) NNW of the SE corner of the pier,
and 0.91 m (3.0 ft) NNE of the south corner of the pier.



                         BENCH MARK STAMPING:  4662 C 1976
                         DESIGNATION:          866 4662 C

MONUMENTATION:           Metal Rod                             VM#:         4081
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  CJ1476
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   32° 54.4' N (  32.90670)          LONGITUDE:  79° 57.3' W ( -79.95500)


The bench mark is a metal rod set along Basin Road near the gate in the fence
separating the Army Depot and the Port Terminal properties, 14.26 m (46.8 ft) NW
of the steps at the SW end of the concrete pier, 9.39 m (30.8 ft) SE of a
pipeline, 2.44 m (8.0 ft) from a metal witness post and sign, and 1.46 m (4.8
ft) NNE of the wire fence gate.  The datum point is level with the ground, being
the top of a copper-clad steel rod driven 12.2 m (40 ft) to refusal, and encased
in a PVC pipe and concrete kickblock. NOTE: A disk was formerly crimped to the
top of the rod but was removed.

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

                                                                                
Station ID: 8664662                         PUBLICATION DATE:  02/05/2004
Name:       ARMY DEPOT, COOPER RIVER                          
            SC
NOAA Chart: 11527                           Latitude:   32° 54.6' N (  32.91000)
USGS Quad:  NORTH CHARLESTON                Longitude:  79° 57.1' W ( -79.95170)


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


                         BENCH MARK STAMPING:  4662 E 1987
                         DESIGNATION:          866 4662 E

MONUMENTATION:           Tidal Station disk                    VM#:         4083
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Copper-clad steel rod                 OPUS PID:        
LATITUDE:   32° 54.8' N (  32.91330)          LONGITUDE:  79° 57.3' W ( -79.95500)


The bench mark is a disk set at the base of building #838 near the intersection
of Dock and Basin Roads, 23.47 m (77.0 ft) east of the centerline of Dock Road,
21 m (69 ft) NNW of power pole #3901, 12.2 m (40.0 ft) NNW of the centerline of
Basin Road, and 1.22 m (4.0 ft) ENE of building #838.  The bench mark is 0.73 m
(2.4 ft) below the ground, crimped to a copper-clad steel rod driven 6.7 m (22
ft) to refusal, and encased in a 4-inch PVC pipe with a plug and concrete
kickblock.

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

                                                                                
Station ID: 8664662                         PUBLICATION DATE:  02/05/2004
Name:       ARMY DEPOT, COOPER RIVER                          
            SC
NOAA Chart: 11527                           Latitude:   32° 54.6' N (  32.91000)
USGS Quad:  NORTH CHARLESTON                Longitude:  79° 57.1' W ( -79.95170)


                            T I D A L   D A T U M S 


Tidal datums at ARMY DEPOT, COOPER RIVER based on:

     LENGTH OF SERIES:      2 YEARS
     TIME PERIOD:           July 1987 - June 1989
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8665530 CHARLESTON, COOPER RIVER ENTRANCE


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

     HIGHEST OBSERVED WATER LEVEL (09/22/1989)         =  3.143
     MEAN HIGHER HIGH WATER                     MHHW   =  1.809
     MEAN HIGH WATER                            MHW    =  1.707
     North American Vertical Datum              NAVD88 =  0.971
     MEAN SEA LEVEL                             MSL    =  0.957
     MEAN TIDE LEVEL                            MTL    =  0.883
     MEAN LOW WATER                             MLW    =  0.059
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     LOWEST  OBSERVED WATER LEVEL (04/07/1989)         = -0.664

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     CREEK 1976                                  3.506    1.799
     NO 4 1942                                   3.511    1.804
     4662 C 1976                                 2.208    0.501
     4662 E 1987                                 1.958    0.251


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

                                                                                
Station ID: 8664662                         PUBLICATION DATE:  02/05/2004
Name:       ARMY DEPOT, COOPER RIVER                          
            SC
NOAA Chart: 11527                           Latitude:   32° 54.6' N (  32.91000)
USGS Quad:  NORTH CHARLESTON                Longitude:  79° 57.1' W ( -79.95170)


                             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 NGS's Integrated Data Base (IDB PID)
provides geodetic datum based on traditionally leveled and bluebooked ties to
the National Spatial Reference System(NSRS) https://www.ngs.noaa.gov/datasheets/.
The NGS Online Positioning User Service (OPUS PID) provides geodetic datum based
on GPS position & tie it to the NSRS https://www.ngs.noaa.gov/OPUS/.

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.