U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


To reach the tidal bench marks from the intersection of State Highway A1A and
U.S. Highway 1 in New Smyrna Beach, proceed 16 km (10 mi) east then south on
State Highway A1A to the dirt drive leading south on the east side of the dead
end of State Highway A1A, then 0.2 km (0.1 mi) on the dirt road to another dirt
road leading west to the middle dock of three on Mosquito Lagoon.  The bench
marks are located along State Highway A1A and the dirt road leading south.  The
tide gage and staff were located 19 m (62 ft) west of the shore inside the
northeast corner of the T-section dock.


                         T I D A L   B E N C H   M A R K S
                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


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


                 PRIMARY BENCH MARK STAMPING:  R 212 VOL 72
                         DESIGNATION:          R 212 VOL

MONUMENTATION:           Survey disk                           VM#:         5310
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AK6911
SETTING CLASSIFICATION:  Concrete post                         OPUS PID:        
LATITUDE:   28° 55.8' N (  28.92917)          LONGITUDE:  80° 49.5' W ( -80.82472)


The primary bench mark is a disk set in the top of a prefabricated concrete post
projecting 0.06 m (0.2 ft) above the level of the ground, 42.67 m (140.0 ft)
south of the extended centerline of the gated sand road on the south side of the
turtle mound as measured along the east edge of State Highway A1A, 18.29 m (60.0
ft) south of a wooden power pole, 13.72 m (45.0 ft) east of the approximate
centerline of State Highway A1A, 7.62 m (25.0 ft) west of the approximate
centerline of an abandoned sand road east of and parallel with State Highway
A1A, 3.96 m (13.0 ft) WNW of a 3.66 m (12.0 ft) high cabbage palm, 2.60 m (8.5
ft) west of a carsonite witness post, and 0.15 m (0.5 ft) west of a metal
witness post.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


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


                         BENCH MARK STAMPING:  R 211 VOL 72
                         DESIGNATION:          R 211 VOL

MONUMENTATION:           Bench Mark disk                       VM#:         5309
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AK6912
SETTING CLASSIFICATION:  Concrete post                         OPUS PID:        
LATITUDE:   28° 55.9' N (  28.93167)          LONGITUDE:  80° 49.6' W ( -80.82611)


The bench mark is a disk set in the top of a prefabricated concrete post
recessed 0.09 m (0.3 ft) below the level of the ground, 91.44 m (300.0 ft) NNE
of the intersection of State Highway A1A (Turtle Mound Road) and the approximate
centerline of the gated sand on the south side of the Turtle Mound historical
site, 43.59 m (143.0 ft) NNW of survey mark 79 78 A 10 RM NO 1, 13.59 m (44.6
ft) east of the approximate centerline of State Highway A1A, 7.92 m (26.0 ft)
north of a 3.66 m (12.0 ft) High Cabbage Palm, 1.52 m (5.0 ft) south of a metal
witness post and 0.09 m (0.3 ft) south of a carsonite witness post.



                         BENCH MARK STAMPING:  79 78 A10 RM NO 1
                         DESIGNATION:          79 78 A 10 RM 1

MONUMENTATION:           Bench Mark disk                       VM#:         5312
AGENCY:                  Florida Department of Transportation
                         (FLDT)                                IDB PID#:  AK5463
SETTING CLASSIFICATION:  Concrete post                         OPUS PID#:       
LATITUDE:   28° 55.9' N (  28.93167)          LONGITUDE:  80° 49.6' W ( -80.82611)


The bench mark is a disk set in the top of a prefabricated concrete post level
of the ground, 130.94 m (429.6 ft) north of the extended centerline of the wood
walkway to the turtle mound historical site on the west side of State Highway
A1A, 14.17 m (46.5 ft) east of the approximate centerline of State Highway A1A,
7.19 m (23.6 ft) NNW of survey mark 79 78 A10, 3.72 m (12.2 ft) west of the
approximate centerline of the remnant paved road running parallel with the east
side of State Highway A1A, and 0.24 m (0.8 ft) south of a FLDOT metal witness
post.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


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


                         BENCH MARK STAMPING:  79 78 A 10
                         DESIGNATION:          79 78 A 10

MONUMENTATION:           Survey disk                           VM#:         5314
AGENCY:                  FL Department of Transportation (FLDT) IDB PID#:  AK5461
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID#: AK5461
LATITUDE:   28° 55.9' N (  28.93139)          LONGITUDE:  80° 49.6' W ( -80.82611)


The bench mark is a disk set in the top of a concrete monument recessed 0.09 m
(0.3 ft) below the level of the ground, 123.75 m (406.0 ft) north of the
extended centerline of the wood walkway to the turtle mound historical site on
the west side of State Highway A1A, 14.63 m (48.0 ft) east of the approximate
centerline of State Highway A1A, 7.19 m (23.6 ft) south of survey mark RM NO 1
79 78 A 10, 3.72 m (12.2 ft) west of the approximate centerline of the remnant
paved road running parallel with the east side of State Highway A1A, and 0.49 m
(1.6 ft) east of a metal witness post.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


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


                         BENCH MARK STAMPING:  1223 J 1987
                         DESIGNATION:          872 1223 J TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:        17182
AGENCY:                  FL Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AK7013
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: AK7013
LATITUDE:   28° 55.7' N (  28.92889)          LONGITUDE:  80° 49.5' W ( -80.82417)


The bench mark is a disk located 65.23 m (214.0 ft) north of the approximate
centerline of the east end of east-west sand road that is opposite the visitor
information center, 18.96 m (62.2 ft) north of a wooden power pole on the west
side of the north-south sand road, 17.59 m (57.7 ft) NNW of a wooden power pole
on the east side of the north-south sand road, 2.90 m (9.5 ft) ENE of the center
of a dim north-south sand road and 1.77 m (5.8 ft) SW, and 0.30 m (1.0 ft) south
of carsonite witness posts.  The bench mark is crimped to the top of a stainless
steel rod encased in a PVC pipe and concrete kickblock, recessed 0.21 m (0.7 ft)
below the level of the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


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


                         BENCH MARK STAMPING:  1223 K 1987
                         DESIGNATION:          872 1223 K TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:        17183
AGENCY:                  FL Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AK7014
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: AK7014
LATITUDE:   28° 56.1' N (  28.93528)          LONGITUDE:  80° 49.7' W ( -80.82833)


The bench mark is a disk located 112.78 m (370.0 ft) SSE of the south side of
the Canaveral National Seashore entrance booth, 49.98 m (160.7 ft) north of the
approximate centerline of the northernmost paved driveway of a boat ramp parking
area, 7.22 m (23.7 ft) ENE of a wooden power pole, 5.85 m (19.2 ft) WSW of the
approximate centerline of State Highway A1A and 3.66 m (12.0 ft) ENE of a
carsonite witness post.  The bench mark is crimped to the top of a stainless
steel rod encased in a PVC pipe and concrete kickblock level with the ground.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


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


                         BENCH MARK STAMPING:  K 212 1963
                         DESIGNATION:          K 212

MONUMENTATION:           Bench Mark disk                       VM#:        17184
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  AK0553
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   28° 55.7' N (  28.92861)          LONGITUDE:  80° 49.5' W ( -80.82417)


The bench mark is a disk set in the top of a concrete monument projecting 0.09 m
(0.3 ft) above the level of the ground, 54.56 m (179.0 ft) south of the
approximate centerline of the east end of the east-west sand road that is
opposite the visitor information center, 14.78 m (48.5 ft) south of a sanitary
sewer manhole cover, 13.72 m (45.0 ft) ESE of the NE corner of a wood cottage,
9.75 m (32.0 ft) east of the SE corner of the wood cottage, 6.71 m (22.0 ft) SW
of the approximate centerline of a north-south sand road, 1.22 m (4.0 ft)SW of a
wooden power pole, and 0.30 m (1.0 ft) north of a carsonite witness post.



                         BENCH MARK STAMPING:  79 78 A 11
                         DESIGNATION:          79 78 A 11 FLDNR

MONUMENTATION:           Bench Mark disk                       VM#:        19511
AGENCY:                  FL Department of Transportation (FLDT) IDB PID#:  AK5465
SETTING CLASSIFICATION:  Concrete headwall                     OPUS PID:        
LATITUDE:   28° 56.4' N (  28.93944)          LONGITUDE:  80° 49.9' W ( -80.83222)


The bench mark is a disk located 57.61 m (189.0 ft) SE of the south end of a
concrete headwall, 6.86 m (22.5 ft) NE of the centerline of State Road A1A, and
5.49 m (18.0 ft) SW of the brush line.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  8 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


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


                         BENCH MARK STAMPING:  79 78 A 12
                         DESIGNATION:          79 78 A 12 FLDNR

MONUMENTATION:           Bench Mark disk                       VM#:        19512
AGENCY:                  FL Department of Transportation (FLDT) IDB PID#:  AK5469
SETTING CLASSIFICATION:  Concrete post                         OPUS PID#: AK5469
LATITUDE:   28° 57.1' N (  28.95167)          LONGITUDE:  80° 50.4' W ( -80.84056)


The bench mark is a disk 19.20 m (63.0 ft) SE of a power pole, 10.67 m (35.0 ft)
SE of the centerline of 15th Street and 6.86 m (22.5 ft) NE of the center line
of State Road A1A.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  9 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


                            T I D A L   D A T U M S 


Tidal datums at TURTLE MOUND based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           March 1979 - March 1979
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8720030 FERNANDINA BEACH, AMELIA RIVER


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

     North American Vertical Datum              NAVD88 =  0.176
     MEAN HIGHER HIGH WATER                     MHHW   =  0.170
     MEAN HIGH WATER                            MHW    =  0.139
     MEAN TIDE LEVEL                            MTL    =  0.070
     MEAN SEA LEVEL                             MSL    =  0.055
     MEAN LOW WATER                             MLW    =  0.001
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     R 212 VOL 72                                3.440    3.301
     R 211 VOL 72                                2.279    2.140
     79 78 A10 RM NO 1                           3.012    2.873
     79 78 A 10                                  2.945    2.806
     1223 J 1987                                 4.200    4.061
     1223 K 1987                                 1.578    1.439
     K 212 1963                                  4.159    4.020
     79 78 A 11                                  1.418    1.279
     79 78 A 12                                  1.462    1.323


Foot Notes:

Geodetic heights of the bench marks meet all NOAA/NOS/NGS quality control
standards for Second Order, Class 1 leveling.  It is advised that a confirmation
set of levels be established for bench marks 1223 J 1987, 1223 K 1987, 79 78 A
11, 79 78 A 12, and K 212 1963 to verify height differences before using tidal
bench mark elevation information.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page 10 of 10

                                                                                
Station ID: 8721223                         PUBLICATION DATE:  01/20/2011
Name:       TURTLE MOUND                                      
            FL
NOAA Chart: 11485                           Latitude:   28° 55.6' N (  28.92670)
USGS Quad:  ARIEL                           Longitude:  80° 49.5' W ( -80.82500)


                             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.