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

                                                                                
Station ID: 8655875                         PUBLICATION DATE:  05/31/2005
Name:       SEA LEVEL, CORE SOUND                             
            NC
NOAA Chart: 11550                           Latitude:   34° 52.5' N (  34.87500)
USGS Quad:  ATLANTIC                        Longitude:  76° 20.6' W ( -76.34330)


To reach the benchmarks from the Post Office in Sea Level, NC, proceed east on
US 70 for 0.64 km (0.4 miles) to Nelson Neck Road (SR 1373), then turn right and
proceed south on Nelson Neck Road for 1.77 km (1.10 miles) to Taylor Seafood
Company.  The benchmarks are in the vicinity of Taylor Seafood Company.  The
tide station was located behind the warehouse on the wharf.


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


                 PRIMARY BENCH MARK STAMPING:  5875 D 2004

MONUMENTATION:           Tidal Station disk                    VM#:        17632
AGENCY:                  National Ocean Service (NOS)          IDB PID#:  DG7037
SETTING CLASSIFICATION:  Stainless steel rod in sleeve         OPUS PID:        
LATITUDE:   34° 51.4' N (  34.85670)          LONGITUDE:  76° 23.2' W ( -76.38670)


The primary bench mark is a disk located 45.15 m (148.1 ft) east of power pole
number CK04, 7.25 m (23.8 ft) north of the centerline of Nelson Neck Road, and
0.75 m (2.5 ft) south of power pole number CK05.  The bench mark is set 8 cm
(0.3 ft) below grade, crimped to a stainless steel rod dirven 21.9 m (72 ft) to
refusal, in a sleeve extending to a depth of 1.0 m (3 ft), and encased in a
5-inch PVC pipe with concrete kickblock and NOS logo cap. Note-This bench mark
does not meet the specifications for a Class A rod mark. 



                         BENCH MARK STAMPING:  5875 A 2004

MONUMENTATION:           Tidal Station disk                    VM#:        17633
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete dock                         OPUS PID#: DG7038
LATITUDE:   34° 51.4' N (  34.85649)          LONGITUDE:  76° 23.2' W ( -76.38746)


The bench mark is disk set flush in a concrete dock located on the SW corner of
Taylor Seafood Dock, 15.50 m (50.8 ft) south of the NW corner of the office
building, 3.95 m (13.0 ft) SW of the SW corner of the office building, and 0.27
m (0.9 ft) east of the west side of the dock. 

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

                                                                                
Station ID: 8655875                         PUBLICATION DATE:  05/31/2005
Name:       SEA LEVEL, CORE SOUND                             
            NC
NOAA Chart: 11550                           Latitude:   34° 52.5' N (  34.87500)
USGS Quad:  ATLANTIC                        Longitude:  76° 20.6' W ( -76.34330)


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


                         BENCH MARK STAMPING:  5875 B 2004

MONUMENTATION:           Tidal Station disk                    VM#:        17634
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete step                         OPUS PID:        
LATITUDE:   34° 51.4' N (  34.85670)          LONGITUDE:  76° 23.2' W ( -76.38670)


The bench mark is a disk set in a concrete step located at the entrance door of
the Mullet building, 22.51 m (73.8 ft) SW of the NW corner of the Freezer
building, 16.26 m (53.4 ft) NNW of the NW corner of the Ice House building, 1.45
m (4.76 ft) NE of the NE corner of the Mullet building, and 0.30 m (1.0 ft)
above the gound. 



                         BENCH MARK STAMPING:  5875 C 2004

MONUMENTATION:           Tidal Station disk                    VM#:        17635
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete pad                          OPUS PID:        
LATITUDE:   34° 51.4' N (  34.85670)          LONGITUDE:  76° 23.2' W ( -76.38670)


The bench mark is a disk set in a concrete pad located at the NE corner of the
Freezer building, 29.72 m (97.5 ft) north of the SE corner of the Freezer
building, 28.30 m (92.8 ft) SSW of the NW corner of the fence around the
property, 22.01 m (72.2 ft) west of the centerline of Nelson Neck Road, and 0.9
m (3.0 ft) above ground. 

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

                                                                                
Station ID: 8655875                         PUBLICATION DATE:  05/31/2005
Name:       SEA LEVEL, CORE SOUND                             
            NC
NOAA Chart: 11550                           Latitude:   34° 52.5' N (  34.87500)
USGS Quad:  ATLANTIC                        Longitude:  76° 20.6' W ( -76.34330)


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


                         BENCH MARK STAMPING:  5875 E 2004

MONUMENTATION:           Tidal Station disk                    VM#:        17636
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Concrete culvert                      OPUS PID:        
LATITUDE:   34° 51.4' N (  34.85670)          LONGITUDE:  76° 23.0' W ( -76.38330)


The bench mark is set in the south end of a concrte culvert cover, 19.90 m (65.3
ft) east of the west edge of the road, 19.05 m (62.5 ft) SE of power pole number
CK10, 8.12 m (26.6 ft) west of the east edge of the water, and 0.03 m (0.1 ft)
above the ground. 

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

                                                                                
Station ID: 8655875                         PUBLICATION DATE:  05/31/2005
Name:       SEA LEVEL, CORE SOUND                             
            NC
NOAA Chart: 11550                           Latitude:   34° 52.5' N (  34.87500)
USGS Quad:  ATLANTIC                        Longitude:  76° 20.6' W ( -76.34330)


                            T I D A L   D A T U M S 


Tidal datums at SEA LEVEL, CORE SOUND based on:

     LENGTH OF SERIES:      2 MONTHS
     TIME PERIOD:           May 2004 - June 2004
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8656483 BEAUFORT, DUKE MARINE LAB


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

     North American Vertical Datum              NAVD88 =  0.224
     MEAN HIGHER HIGH WATER                     MHHW   =  0.220
     MEAN HIGH WATER                            MHW    =  0.208
     MEAN TIDE LEVEL                            MTL    =  0.121
     MEAN SEA LEVEL                             MSL    =  0.120
     MEAN LOW WATER                             MLW    =  0.033
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     5875 D 2004                                 0.726    0.518
     5875 A 2004                                 1.588    1.380
     5875 B 2004                                 1.417    1.209
     5875 C 2004                                 1.748    1.540
     5875 E 2004                                 1.127    0.919


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

                                                                                
Station ID: 8655875                         PUBLICATION DATE:  05/31/2005
Name:       SEA LEVEL, CORE SOUND                             
            NC
NOAA Chart: 11550                           Latitude:   34° 52.5' N (  34.87500)
USGS Quad:  ATLANTIC                        Longitude:  76° 20.6' W ( -76.34330)


                             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.