U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  8

                                                                                
Station ID: 9415144                         PUBLICATION DATE:  11/23/2010
Name:       PORT CHICAGO, SUISUN BAY                          
            CA
NOAA Chart: 18656                           Latitude:   38°  3.4' N (  38.05600)
USGS Quad:  VINE HILL                       Longitude: 122°  2.4' W (-122.03950)


To reach the tidal bench marks, take Highway 4 east to Port Chicago Highway,
Naval Weapons Station exit, proceed north 2 km (1 mi) to the Naval Weapons
Center gate on the right, obtain a pass to the tide gauge area, get back on the
main road towards the railroad crossing and fork left through guarded gate,
follow the railroad tracks on base for 3 km (2 mi) to just past a bridge and
bear left at a fork onto Johnson Road, then follow Johnson Road 2 km (1 mi) to
the water. The bench marks are in the vicinity on the Naval Weapons Center 
property.  The tide gauge is on the SE end of the Tug Pier.


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


                 PRIMARY BENCH MARK STAMPING:  5144 H 1976
                         DESIGNATION:          941 5144 H

MONUMENTATION:           Tidal Station disk                    VM#:          994
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AH7472
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: AH7472
LATITUDE:   38°  3.3' N (  38.05525)          LONGITUDE: 122°  2.3' W (-122.03844)


The primary bench mark is a disk set on a rod located at the SE corner of
Johnson Road and White Road, about 96.9 m (317.9 ft) SE of the inshore end of
Port Chicago barge pier where the tide station is located, 49.68 m (163.0 ft)
east of the centerline of Johnson Road, 30.18 m (99.0 ft) west of the westerly
corner of Building A16, 30.18 m (99.0 ft) south of the centerline of White Road,
26.82 m (88.0 ft) NE of the NE corner of Building A14, 14.63 m (48.0 ft) NE of
the most easterly railroad track, and 1.37 m (4.5 ft) south of a 4-inch square
witness post. The bench mark is set 3 cm (0.1 ft) above ground level, crimped to
a stainless steel rod driven 9.80 m (32.2 ft) to refusal, and encased in a
4-inch PVC pipe.  

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  8

                                                                                
Station ID: 9415144                         PUBLICATION DATE:  11/23/2010
Name:       PORT CHICAGO, SUISUN BAY                          
            CA
NOAA Chart: 18656                           Latitude:   38°  3.4' N (  38.05600)
USGS Quad:  VINE HILL                       Longitude: 122°  2.4' W (-122.03950)


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


                         BENCH MARK STAMPING:  HARLEY 1954
                         DESIGNATION:          HARLEY 1954
                         ALIAS:                HARLEY 1982

MONUMENTATION:           Triangulation Station disk            VM#:          996
AGENCY:                  US Coast and Geodetic Survey
                         (USC&GS)                              IDB PID#:  JT2039
SETTING CLASSIFICATION:  Concrete sidewalk                     OPUS PID:        
LATITUDE:   37°  2.7' N (  37.04472)          LONGITUDE: 122°  1.9' W (-122.03136)


The bench mark is a disk set flush in the concrete sidewalk on the west side of
the Taylor Boulevard Bridge over the Southern Pacific Railroad, located at the
crest of the bridge across from the painted number "34" which is on the east
guard rail, 171.3 m (562.0 ft) south of Bench Mark CT 26, 4.30 m (14.1 ft) west
of the centerline of Taylor Boulevard, 0.53 m (1.7 ft) east of the west guard
rail, 0.06 m (0.2 ft) west of the curb edge, and 0.3 m (1 ft) above road level
in center of white painted cross.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  8

                                                                                
Station ID: 9415144                         PUBLICATION DATE:  11/23/2010
Name:       PORT CHICAGO, SUISUN BAY                          
            CA
NOAA Chart: 18656                           Latitude:   38°  3.4' N (  38.05600)
USGS Quad:  VINE HILL                       Longitude: 122°  2.4' W (-122.03950)


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


                         BENCH MARK STAMPING:  5144 F 1976
                         DESIGNATION:          941 5144 F

MONUMENTATION:           Tidal Station disk                    VM#:          997
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID:        
LATITUDE:   37°  3.3' N (  37.05425)          LONGITUDE: 122°  2.3' W (-122.03878)


The bench mark is a disk set flush and horizontally in a 0.76 m (2.5 ft) square
concrete base, located 35.05 m (115.0 ft) WNW of the center of the intersection
of Johnson and Wilson Roads, 13.72 m (45.0 ft) SSW of the northern pole
supporting three transformers, 13.26 m (43.5 ft) NW of the north face of
Building A3, 8.84 m (29.0 ft) north of the centerline of Wilson Road, 3.78 m
(12.4 ft) NE of the railroad track switch, 3.35 m (11.0 ft) north of northern
rail of a single railroad track, 0.09 m (0.3 ft) west of the NE corner of the
concrete base, and 0.12 m (0.4 ft) above ground.



                         BENCH MARK STAMPING:  5144 G 1976
                         DESIGNATION:          941 5144 G

MONUMENTATION:           Tidal Station disk                    VM#:          998
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete loading dock                 OPUS PID:        
LATITUDE:   37°  3.2' N (  37.05319)          LONGITUDE: 122°  2.3' W (-122.03767)


The bench mark is a disk set flush in the extreme SE corner of a concrete
loading dock on the south side of Transfer Building A177, 82.30 m (270.0 ft)
west of the center of the intersection of Johnson and Pickett Roads, 17.37 m
(57.0 ft) north of the centerline of Pickett Road, 6.34 m (20.8 ft) SE of the SE
corner of building, and 1.83 m (6.0 ft) north of the northern-most rail of the
three railroad tracks that run parallel to the south side of the building.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  8

                                                                                
Station ID: 9415144                         PUBLICATION DATE:  11/23/2010
Name:       PORT CHICAGO, SUISUN BAY                          
            CA
NOAA Chart: 18656                           Latitude:   38°  3.4' N (  38.05600)
USGS Quad:  VINE HILL                       Longitude: 122°  2.4' W (-122.03950)


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


                         BENCH MARK STAMPING:  5144 J 1976
                         DESIGNATION:          941 5144 J

MONUMENTATION:           Tidal Station disk                    VM#:          999
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:  AE7867
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   37°  3.2' N (  37.05267)          LONGITUDE: 122°  2.2' W (-122.03589)


The bench mark is a disk located 0.5 km (0.3 mi) SE along Johnson Road from the
barge pier, 32.61 m (107.0 ft) NW of fire hydrant #216, 20.42 m (67.0 ft) SW of
the most westerly track, 17.68 m (58.0 ft) SE of utility pole #1181, 11.58 m
(38.0 ft) SW of the centerline of Johnson Road, and 0.90 m (3.0 ft) SE of a
witness post. The bench mark is set 6 cm (0.2 ft) above ground level, crimped to
a stainless steel rod driven 9.80 m (32.2 ft) to refusal, and encased in a
4-inch PVC pipe.



                         BENCH MARK STAMPING:  5144 K 1976
                         DESIGNATION:          941 5144 K

MONUMENTATION:           Tidal Station disk                    VM#:         1000
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   37°  3.0' N (  37.05047)          LONGITUDE: 122°  2.0' W (-122.03381)


The bench mark is a disk located 0.8 km (0.5 mi) SE along Johnson Road from the
barge pier, 23.47 m (77.0 ft) NW of most westerly track at centerline of where
track crosses Johnson Road, 10.21 m (33.5 ft) SW of the centerline of Johnson
Road, 7.77 m (25.5 ft) north of a street-light utility pole #1142, 3.99 m (13.1
ft) west of railroad crossing sign, and 1.0 m (3.3 ft) SE of a witness post. 
The bench mark is set 3 cm (0.1 ft) above ground level, crimped to a stainless
steel rod driven 18.29 m (60.0 ft) to refusal, and encased in a 4-inch PVC pipe.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  8

                                                                                
Station ID: 9415144                         PUBLICATION DATE:  11/23/2010
Name:       PORT CHICAGO, SUISUN BAY                          
            CA
NOAA Chart: 18656                           Latitude:   38°  3.4' N (  38.05600)
USGS Quad:  VINE HILL                       Longitude: 122°  2.4' W (-122.03950)


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


                         BENCH MARK STAMPING:  5144 M 1982
                         DESIGNATION:          941 5144 M

MONUMENTATION:           Tidal Station disk                    VM#:         1001
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete loading dock                 OPUS PID:        
LATITUDE:   37°  3.1' N (  37.05197)          LONGITUDE: 122°  2.1' W (-122.03556)


The bench mark is a disk set flush in the top of the SE corner of a loading dock
on the east side of Building A31, 28.04 m (92.0 ft) SW of the centerline of
Johnson Road between Bench Marks 5144 J 1976 and 5144 K 1976, 3.29 m (10.8 ft)
SW of the NE edge of the loading dock, 1.28 m (4.2 ft) NW of the SE edge of the
loading dock, 0.40 m (1.3 ft) NE of the building, and 1.13 m (3.7 ft) above
ground level.



                         BENCH MARK STAMPING:  5144 N 1982
                         DESIGNATION:          941 5144 N

MONUMENTATION:           Tidal Station disk                    VM#:         1002
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete loading dock                 OPUS PID:        
LATITUDE:   37°  3.2' N (  37.05311)          LONGITUDE: 122°  2.4' W (-122.04003)


The bench mark is a disk set flush in the top of the SE corner of the railroad
concrete loading dock on the south side of Building S47SH, 14.02 m (46.0 ft) NW
of the centerline of Holmes Road, 3.26 m (10.7 ft) east of the center of a set
of double doors leading into the building, 1.71 m (5.6 ft) north of the south
edge of the loading dock, 0.40 m (1.3 ft) west of the east edge of the loading
dock above the stairs, 0.12 m (0.4 ft) south of Building S47SH, and 1.19 m (3.9
ft) above ground level.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  8

                                                                                
Station ID: 9415144                         PUBLICATION DATE:  11/23/2010
Name:       PORT CHICAGO, SUISUN BAY                          
            CA
NOAA Chart: 18656                           Latitude:   38°  3.4' N (  38.05600)
USGS Quad:  VINE HILL                       Longitude: 122°  2.4' W (-122.03950)


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


                         BENCH MARK STAMPING:  CT 26
                         DESIGNATION:          26 USN
                         ALIAS:                14 1948

MONUMENTATION:           Bolt                                  VM#:         1003
AGENCY:                  US Army Corps of Engineers (USE)      IDB PID#:  JT0383
SETTING CLASSIFICATION:  Concrete sidewalk                     OPUS PID:        
LATITUDE:   37°  2.8' N (  37.04614)          LONGITUDE: 122°  1.9' W (-122.03217)


The bench mark is the rounded head of a 1-inch brass bolt set in the top at the
north end of the west concrete sidewalk of the Taylor Boulevard bridge over the
Southern Pacific Railroad, 4.72 m (15.5 ft) west of the centerline of Taylor
Boulevard, 2.44 m (8.0 ft) SE of easterly railroad support trussle, 0.46 m (1.5
ft) east of west side of bridge-fac, and about 0.30 m (1.0 ft) above the level
of the road.



                         BENCH MARK STAMPING:  5144 P 1990 RESET 1997
                         DESIGNATION:          941 5144 P RESET

MONUMENTATION:           Tidal Station disk                    VM#:        13892
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Concrete foundation                   OPUS PID#: BBDT12
LATITUDE:   38°  3.3' N (  38.05569)          LONGITUDE: 122°  2.4' W (-122.03922)


The bench mark is a disk set flush in the concrete base of a flag pole at the
head of the tug pier, 14.83 m (48.6 ft) east of the east side of a telephone
booth near the tug office, 3.81 m (12.5 ft) SE of the southern end of a guard
rail which leads to pier, and 0.49 m (1.6 ft) SW of the flag pole.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  8

                                                                                
Station ID: 9415144                         PUBLICATION DATE:  11/23/2010
Name:       PORT CHICAGO, SUISUN BAY                          
            CA
NOAA Chart: 18656                           Latitude:   38°  3.4' N (  38.05600)
USGS Quad:  VINE HILL                       Longitude: 122°  2.4' W (-122.03950)


                            T I D A L   D A T U M S 


Tidal datums at PORT CHICAGO, SUISUN BAY based on:

     LENGTH OF SERIES:      19 YEARS
     TIME PERIOD:           January 1983 - December 2001
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:   


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

     HIGHEST OBSERVED WATER LEVEL (12/03/1983)         =  2.415
     MEAN HIGHER HIGH WATER                     MHHW   =  1.498
     MEAN HIGH WATER                            MHW    =  1.343
     MEAN TIDE LEVEL                            MTL    =  0.785
     MEAN SEA LEVEL                             MSL    =  0.781
     MEAN LOW WATER                             MLW    =  0.226
     MEAN LOWER LOW WATER                       MLLW   =  0.000
     North American Vertical Datum              NAVD88 = -0.335
     LOWEST  OBSERVED WATER LEVEL (01/08/1989)         = -0.447

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     5144 H 1976                                 2.994    1.651
     HARLEY 1954                                12.306   10.963
     5144 F 1976                                 3.742    2.399
     5144 G 1976                                 4.491    3.148
     5144 J 1976                                 2.253    0.909
     5144 K 1976                                 2.672    1.329
     5144 M 1982                                 4.341    2.998
     5144 N 1982                                 4.615    3.271
     CT 26                                       5.753    4.410
     5144 P 1990 RESET 1997                      3.605    2.262


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

                                                                                
Station ID: 9415144                         PUBLICATION DATE:  11/23/2010
Name:       PORT CHICAGO, SUISUN BAY                          
            CA
NOAA Chart: 18656                           Latitude:   38°  3.4' N (  38.05600)
USGS Quad:  VINE HILL                       Longitude: 122°  2.4' W (-122.03950)


                             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.