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

                                                                                
Station ID: 9469439                         PUBLICATION DATE:  03/19/2009
Name:       TIN CITY, BERING SEA                              
            AK
NOAA Chart: 16204                           Latitude:   65° 33.5' N (  65.55830)
USGS Quad:  TELLER (C-7)                    Longitude: 167° 58.5' W (-167.97500)


To reach the tidal bench marks from the bay door on the ENE side of the USAF
living quarters, proceed 0.15 km (0.1 mi) WSW on the gravel road, turn right at
the intersection with another gravel road and proceed NW 0.2 km (0.12 mi) and
then 0.35 km (0.2 mi) SSW around a U shaped bend to the base of the tram which
leads up to the radar, leave the road to continue around the tram building and
turn left and proceed SE downhill 0.2 km (0.12 mi), then turn right and continue
SW around the base of the bluff 0.4 km (0.25 mi) to a gully which leads down to
the beach.  The tide gauge was located on top of the bluff and the orifice was
located on the rock outcrop at the base of the bluff.  The bench marks are
located in rock outcrops along 0.5 km (0.3 mi) of the shoreline east of the
gully.


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


                 PRIMARY BENCH MARK STAMPING:  TIN CITY NO 2 1960
                         DESIGNATION:          946 9439 TIDAL 2

MONUMENTATION:           Tidal Station disk                    VM#:        18436
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID#: BBCC46
LATITUDE:   65° 33.5' N (  65.55911)          LONGITUDE: 167° 58.7' W (-167.97900)


The primary bench mark is a disk set in a large rock outcrop, 31.90 m (104.6 ft)
SW of the east end of the rock outcrop, 25.40 m (83.3 ft) NE of the western edge
of the outcrop and a small channel separating an offshore outcrop, 20.20 m (66.3
ft) south of the base of the dirt bluff, 17.80 m (58.4 ft) NNW of the seaward
extent of the rock outcrop, and 9.97 m (32.7 ft) west of the orifice pipe.

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

                                                                                
Station ID: 9469439                         PUBLICATION DATE:  03/19/2009
Name:       TIN CITY, BERING SEA                              
            AK
NOAA Chart: 16204                           Latitude:   65° 33.5' N (  65.55830)
USGS Quad:  TELLER (C-7)                    Longitude: 167° 58.5' W (-167.97500)


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


                         BENCH MARK STAMPING:  9439 A 2007
                         DESIGNATION:          946 9439 A

MONUMENTATION:           Tidal Station disk                    VM#:        18437
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID:        
LATITUDE:   65° 33.6' N (  65.56000)          LONGITUDE: 167° 58.6' W (-167.97658)


The bench mark is a disk set flush in an offshore rock outcrop, 32.6 m (106.9
ft) SE of the 30 m (100 ft) tall dirt bluff, 13 m (44 ft) SE of the beach line,
6 m (19 ft) SW of the east end of the rock outcrop, 5 m (16 ft) NE of the west
end of the outcrop, and 4 m (14 ft) NNW of the seaward extent of the rock
outcrop.



                         BENCH MARK STAMPING:  9439 B 2007
                         DESIGNATION:          946 9439 B

MONUMENTATION:           Tidal Station disk                    VM#:        18438
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID:        
LATITUDE:   65° 33.6' N (  65.56042)          LONGITUDE: 167° 58.4' W (-167.97300)


The bench mark is a disk set flush in a black rock outcrop that is nearly level
with the beach, 61.30 m (201.0 ft) west of bench mark 946 9439 C, 2.40 m (7.9
ft) south of a 1 m (3 ft) high rock out crop above this bench mark, and 2.40 m
(7.9 ft) north of the seaward edge of the rock outcrop.

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

                                                                                
Station ID: 9469439                         PUBLICATION DATE:  03/19/2009
Name:       TIN CITY, BERING SEA                              
            AK
NOAA Chart: 16204                           Latitude:   65° 33.5' N (  65.55830)
USGS Quad:  TELLER (C-7)                    Longitude: 167° 58.5' W (-167.97500)


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


                         BENCH MARK STAMPING:  9439 C 2007
                         DESIGNATION:          946 9439 C

MONUMENTATION:           Tidal Station disk                    VM#:        18439
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID:        
LATITUDE:   65° 33.6' N (  65.56036)          LONGITUDE: 167° 58.3' W (-167.97169)


The bench mark is a disk set flush in the east end of a large gray and white
rock outcrop, 103.20 m (338.6 ft) west of bench mark 946 9439 D, 61.30 m (201.1
ft) east of bench mark 946 9439 B, 0.72 m (2.4 ft) NNW of the seaward edge of
the rock outcrop, and 0.44 m (1.4 ft) above the rock and sand beach.



                         BENCH MARK STAMPING:  9439 D 2007
                         DESIGNATION:          946 9439 D

MONUMENTATION:           Tidal Station disk                    VM#:        18440
AGENCY:                  National Ocean Service (NOS)          IDB PID#:        
SETTING CLASSIFICATION:  Rock outcrop                          OPUS PID#: BBBG46
LATITUDE:   65° 33.6' N (  65.56022)          LONGITUDE: 167° 58.2' W (-167.96947)


The bench mark is set flush in prominent dark gray rock outcrop, 103.20 m (338.6
ft) ENE of bench mark 946 9439 C, 17.79 m (58.4 ft) SW of the east edge of the
high rock outcrop, 10.30 m (33.8 ft) south of the base of the dirt bluff, 8.90 m
(29.2 ft) east of the west edge of the high rock outcrop, 6.54 m (21.4 ft) NW of
the seaward extent of the rock outcrop, and approximately 2.60 m (9 ft) above
the sand beach.

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

                                                                                
Station ID: 9469439                         PUBLICATION DATE:  03/19/2009
Name:       TIN CITY, BERING SEA                              
            AK
NOAA Chart: 16204                           Latitude:   65° 33.5' N (  65.55830)
USGS Quad:  TELLER (C-7)                    Longitude: 167° 58.5' W (-167.97500)


                            T I D A L   D A T U M S 


Tidal datums at TIN CITY, BERING SEA based on:

     LENGTH OF SERIES:      1 MONTH
     TIME PERIOD:           September 2007 - September 2007
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9491094 RED DOG DOCK


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

     MEAN HIGHER HIGH WATER                     MHHW   =  0.311
     MEAN HIGH WATER                            MHW    =  0.252
     MEAN SEA LEVEL                             MSL    =  0.144
     MEAN TIDE LEVEL                            MTL    =  0.141
     MEAN LOW WATER                             MLW    =  0.030
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     TIN CITY NO 2 1960                          2.405    2.153
     9439 A 2007                                 0.861    0.609
     9439 B 2007                                 1.263    1.011
     9439 C 2007                                 1.261    1.009
     9439 D 2007                                 2.847    2.595


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

                                                                                
Station ID: 9469439                         PUBLICATION DATE:  03/19/2009
Name:       TIN CITY, BERING SEA                              
            AK
NOAA Chart: 16204                           Latitude:   65° 33.5' N (  65.55830)
USGS Quad:  TELLER (C-7)                    Longitude: 167° 58.5' W (-167.97500)


                             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.