I EC Report
4460C1629
INTERSTATE
ELECTRONICS
CORPORATION
Subsidiary of A-T-O Inc.
NAVIGATION AIDS
for
OCEAN WASTE
DISPOSAL CONTROL
Prepared By
lEC-Oceanics
for the
Ocean Disposal Program
U.S. Environmental Protection Agency
under
Contract 68-01-0796
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INTERSTATE REPORT 446OC1629
ELECTRONICS
CORPORATION FEBRUARY 197U
Subsidiary of ATO Inc.
Environmental Engineering Division
(Formerly OceanicS Division)
NAVIGATION AIDS
FOR
OCEAN WASTE DISPOSAL CONTROL
By
Kenneth W. Herkimer
Prepared for the
U.S. ENVIRONMENTAL PROTECTION AGENCY
OCEAN DISPOSAL PROGRAM
Under Contract 68-01-0796
, J
E^".*f I - >**-- **? AT^'TF
It* V.i8r>, ' ;
Prepared by
INTERSTATE ELECTRONICS CORPORATION
Environmental Engineering Division
707 East Vermont Avenue, Post Office Box 3117
Anaheim, CA 92803 Telephone 714-772-2811
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ABSTRACT
This monograph is an extract from a comprehensive study on ocean
waste disposal which was conducted under contract 68-01-0796 for
the Ocean Disposal Program of the Environmental Protection
Agency.
As a part of the study the types of navigation aids in existence
and in use along the U.S. coastline were reviewed to determine
their suitability for use in control of ocean waste disposal
operations.
This monograph presents a description and summary of the
capabilities of the most prominent systems. A short list of
selected current information sources is provided.
4460C1629
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TABLE OF CONTENTS
Section P§3£
Section 1 - INTRODUCTION
.Section 2 - NAVIGATION AIDS FOR OCEAN DlSl'o.oM, VKHCCLES
2.1 Introduction 2-1
2. 2 Loran A 2-1
2.3 Loran C 2-4
2.4 Omega 2-5
2.5 Differential Omega 2-6
2.6 Decca 2-7
2.7 Radio Direction Finding 2-8
2.8 Radar 2-10
2.9 Vessel Traffic Radar 2-11
2.10 Summary 2-21
Section 3 - BIBLIOGRAPHY
LIST OF FIGURES AND TABLES
Figure 1-1 Maine Disposal Site 1-2
Figure 1-2 Gulf Coast Disposal Site 1-3
Table 2-1 Characteristics of Electronic 2-2
Positioning Systems
446OC1629
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ACKHOHLE DGi; 11HITS
This report is a part of a study that was made possible only
through a hiqh degree of cooperation provided by managers,
scientists and engineers involved in the the study and control of
ocean vraste disposal.
A special note of thanks is expressed to Mr. T.A. T?astler, Chief,
Ocean Disposal Program, and his scientific and technical staff
including in particular, William Musser and BarBara Wynal.
This report was written by Mr. K.W. Herkimer as a part of a
comprehensive study of ocean waste disposal in selected
geographic areas.
The readers comments and suggestions are solicited and should be
addressed to Mr. Sam Kelly, Project Manager.
R.C. Timme
Division Manager
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Section 1
INTRODUCTION
In February of 1973, the Environmental Protection Agency
undertook a comprehensive study of ocean waste disposal practices
in six geographic areas. The purpose of the study was to acquire
information to assist the Ocean Disposal Program of the U.S.
Environmental Protection Agency in the development of criteria
for the control of ocean waste disposal.
During this study, it became apparent that in many cases
navigation ability was a significant factor in insuring that
material was deposited in the designated disposal area. Some
locations such as one shown in Figure 1-1 have visible landmarks
that are used for taking bearings in good weather. Other sites,
such as one shown in Figure 1-2 are far from shore and require
the use of advanced navigation techniques.
As an aid to planners, the available navigation aids for each
disposal site authorized in the Federal Register were cataloged.
This information was provided in report 4460C1545, An Atlas of
2i§22sal sites.
4460C1629 1-1
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INTRODUCTION
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INTRODUCTION
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Section 2
NAVIGATION AIDS FOR OCEAN DISPOSAL VEHICLES
2.1 INTRODUCTION
The majority of the tugs and self-propelled vessels are equipped
with various types of navigation equipment, including
gyrocompass, radio direction finders, and radar. The long-range
tugs have, in addition, Loran A receivers. As a part of this
study, an analysis was made of existing electronic navigation
aids available on the U.S. coastline. A summary of
characteristics and descriptions of these systems is presented in
Table 2-1.
The navigation systems discussed in the following paragraphs are
systems that are now in existence and in use along the nations'
coastlines. The equipments and systems covered herein are
presented for the purposes of evaluation in the event that ocean
disposal criteria, to include navigation systems, are
established.
2.2 LORAN-A
Loran-A is a hyperbolic system of radio navigation available
throughout much of the ocean areas of the northern hemisphere.
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446OC1629
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NAVIGATION AIDS
The system employs synchronized pairs of transmitting stations,
master and slave, which transmit pulse signals with a constant
time interval between them. Loran provides hyperbolic lines of
position which are fixed relative to the earth's surface, as are
latitude and longitude lines. These lines of position can be
crossed with each other or with sun lines, star lines, or other
broadcast stations. Special receivers, Loran charts, and tables
are required for use of the Loran system. Both ground and
skywave signals are used with Loran-A. For the purpose of near
shore work, only the ground wave signals will be considered. The
range is 650 to 900 miles during the day, and the accuracy is,
typically, 1.5 miles over 80 percent of the areas covered.
Loran-A is useful on the Atlantic coast, Pacific northwest,
Hawaii, and Gulf of Mexico areas. The southwest coast of the
United States is limited to a single line of position because of
the distance in placement of the slave stations. A second line
of position must be taken using an ADF, console, radar, sun, or
star sightings. The Loran-A system was scheduled for removal and
replacement by Loran-C and Omega by 1975; however, a definite
date has not been established and service is likely to continue
through 1980.
4460C1629 2-3
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NAVIGATION AIDS
2.3 LORAN-C
The Loran-C navigation system is a long baseline hyperbolic,
area-coverage system, employing time difference measurements of
signals received from three transmitters. It is basically a
Loran-A system with the following improvements:
a. Low frequency transmission (100 kHz) for extended
range.
b. Pulse envelope measurement and phase measurement of the
radio frequency signal provide a fine time-difference
measurement.
c. Automatic instrumentation aboard the ship can provide a
continuous position indication.
d. Higher average transmitting power and phase coding of
the multipulse groups allows station identification and
discrimination between ground and skywaves.
The ground wave coverage of Loran-C extends to approximately 1200
nautical miles. The accuracy is, typically, 1500 feet over 95
percent of the coverage area. Loran-C may be considered useful
on the Atlantic and Gulf coasts, but not on the west coast of the
United States. The Coast Guard presently has a budget request of
more than $5 million to replace the approximately 30 Loran-A
stations with 11 new Loran-C stations and modify six others to
cover the continental coastline and southern Alaska. The
existing Loran-C system has 8 chains containing a total of 31
2-4 446OC1629
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NAVIGATION AIDS
transmitting stations. Several of the existing Loran-C stations
are located in southeast Asia.
2.4 OMEGA
Omega is a long-range radio navigation system utilizing phase
difference measurements of 10.2 kHz carrier frequencies received
from each of two stations whose transmissions are phase-
synchronized. Hyperbolic lines of position of constant phase
difference with the stations lying at the foci of the hyperbolas
provide position fix at the intersection of the two lines of
position. The accuracy of the fix is proportional to the LOP
angles of intersections, 90° being optimum, characteristic of CW
phase measuring systems. Cyclic ambiguity causes isophase LOPs
or lanes every eight nautical miles. To increase the lane
ambiguity these stations cyclically transmit the CW waves at
several frequencies i.e., 610.2 kHz, 13,6 kHz, and 11.33 kHz with
a 0.2 second off-period between each transmission. With a two-
frequency receiver, the resolution or lane ambiguity increases to
24 nautical miles, and with a three frequency receiver improves
to 72 nautical miles. Generally, with some minimal dead
reckoning navigation equipment aboard the vessel, lane ambiguity
is easily resolved. The propagation of Omega signals conforms to
the earth/ionosphere wave guide which is a diagonally varying
dimension along the propagation path. This variation in
4460C1629 2-5
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NAVIGATION AIDS
ionospheric height produces an effective variation in propagation
velocity, which must be compensated for as a function of time and
approximate position to assure predictable phase comparison. The
variation predictions known as skywave corrections have been
tabulated based on a prediction model as a function of time and
day for a specific location. Results of measurement programs
have shown an operational accuracy of one to two nautical miles
rms depending on time of day. Improved accuracy is possible
using a Differential Omega approach.
2.5 DIFFERENTIAL OMEGA
In the Differential Omega concept, a remote Omega receiver at a
known geographic location is utilized to correct certain
unpredictable propagation anomalies thereby resulting in improved
fix accuracy. It is assumed that the Omega receiver used for
position fixing is experiencing the same unpredictable variations
as the remote Omega receiver at the known location and, hence,
suitable corrections may be determined and applied to correct the
data received by the actual navigation receiver. This approach
removes time dependent errors and increases accuracy
repeatability to approach the relative accuracy of the two
receivers operating in a simultaneous environment. Experimental
data obtained with Differential Omega shows an improvement of 4
to 1 over a conventional Omega system with an average LOP error
2-6 U46OC1629
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NAVIGATION AIDS
of 4 to 7 centicycles at night and 1 to 3 centicycles during the
day (1 centicycle equals approximately 1 microsecond, which is
150 meters on the baseline).
2.6 DECCA
The British-developed Decca system is a hyperbolic radio
navigation system which utilizes low-frequency (70-100 kHz) CW
transmission signals from a master and three slave stations to
provide a position fix. Each station transmits a stable CW
frequency signal with a fixed relationship to the frequencies of
the other three stations. Phase comparison of the signals
produces hyperbolic LOP where the phases are equal. Typical
frequencies transmitted would be as follows:
a. Master station 85 (6F)
b. Red slave station 113.333 (8F)
c. Green slave station 127.500 (9F)
d. Purple slave station 70.833 (5F)
These frequencies are multiples of frequency F which in this case
is 14.166 kHz. The receiver incoming frequency signals are
multiplied by factors to produce frequency differences for the
stations which are either 30F (purple) , 18F (green), or 24F
(red). These differences are measured by a phase meter of the
continuously integrating type (deccameter) which indicates total
4460C1629 2-7
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NAVIGATION AIDS
and fractions of cycle that the receiver passes through.
Instrument accuracy is on the order of 1 to 50 of a lane
corresponding to five yards along the baseline. The Decca system
utilizes a lane identification technique for solution of the lane
ambiguity problem. Each station transmits, in addition to its
fine fixing signal, a lane identification signal by a second
transmission at specified intervals. This technique, coupled
with a comparison of the F frequency for each of the three phase
comparison systems for half a second, reduces lane ambiguity to
1/100 of a lane. Practical coverage for Decca is limited to
about 200 nautical miles because of continuous wave propagation
and skywave contamination. At this time, a Decca system is in
operation on the east coast of the United States. California has
proposed the installation of a Decca system on the west coast;
however, this has not been finalized. The major drawback of the
Decca system is the special receivers required, which must be
leased from the British-owned Decca company.
2.7 RADIO DIRECTION FINDING
The use of ground-based radio direction finders for fixed
locations has been utilized for many years. In this system,
transmissions from the vessels are received at two shore RDF
stations from which bearings to the vessel are measured. The two
bearings uniquely fix vessel location. The basic principle of
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NAVIGATION AIDS
direction finding (DF) is the measurement of differential
distance to the transmitter using a loop or Adcock type antenna.
Currents are generated in each vertical segment of the loop,
induced by vertically polarized transmissions, when the loop is
90° to the direction of the arrived signal. Many types of RDF
antennas are produced, but the Adcock type is perhaps most
attractive for a shorebased RDF station. In its simplest form,
this antenna consists of two vertical antennas connected to a
receiver. Operation is similar to the loop antenna, the null
indicating signal direction. Because of the size of antennas
utilized in the 400-kHz to 3-MHz range, physical rotation of the
antenna is not practical and a goniometer in conjunction with
four or eight antenna towers is used. The goniometer is an
instrument consisting of two sets of windings at right angles to
each other with a central rotor which, in effect, translates the
received radio field at the antennas into a miniature magnetic
field in which the rotor operates. The angle output of the
goniometer rotor then provides the direction of the transmitted
signal. Accuracy of an RDF system depends not only on
instrumentation errors, but also on external error factors such
as phase interference effects, polarization errors, tilt of the
ionospheric layer, and site irregularities. In a modern RDF
system, bearing accuracies of +1° with calibration corrections
are possible. At night with skywave contamination the accuracy
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NAVIGATION AIDS
may vary 2° at 100 nautical miles, and as much as 4° at 500
nautical miles.
2.8 RADAR
Vessel location using a shorebased radar is determined from the
time elapsed between transmission and reception of a radar signal
(range) and the radar beam antenna directivity (bearing). The
operation principles of a radar in its simplest form utilize a
transmitter which generates high-power, short-duration pulses
which are radiated in a narrow beam by a parabolic reflector
which is rotated mechanically or electrically in azimuth. When
the pulse strikes the target a small amount of power is radiated
back to the antenna and amplified in a receiver. The receiver
output is displayed in a pulse position indicator (oscilloscope).
The radial scan is generated in synchronism with the transmitted
pulse rate and a rotary scan with the azimuth rotational rate.
This causes a spot to be illuminated on the PPI scope in which
the distance and azimuth are proportional to the true position of
the target. When the target is cooperative, a secondary radar
(radar beacon transponder) can be used which reduces power
requirements of the radar transmitter and reduces clutter by
utilizing different frequencies. Modulation techniques can be
incorporated on the beacon to provide identification and other
coded data. The frequency of radar operation varies depending on
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NAVIGATION AIDS
range, environment, and accuracy required. Generally, radar
range accuracy, which is primarily a function of pulse duration
and display resolution, is on the order of 1000 feet, and bearing
accuracy, which depends on azimuth beam width, is less than 1°.
Because of the high operating frequencies of radar systems, line-
of-sight limits range coverage.
Variations of the radar system are the Cubic Auto Tape and the
Motorola Range Positioning System (RPS). Both of these systems
use a shipboard interrogator and two shorebased transponders.
The accuracy of RPS is 50 feet at 50 miles, and the auto tape
claims accuracies of 6.4 feet at 30 miles. These systems are
limited to line-of-sight, and range in cost between $40,000 and
$90,000.
2.9 VESSEL TRAFFIC RADAR
a« San Francisco Vessel Traffic System j(VTSJ_. - The Ports
and Waterways Safety Act of 1972 (PL 92-340) gives the
Department of Transportation the authority for the
development, administration, and operation of vessel
traffic systems in U.S. ports and harbors. The U.S.
Coast Guard is the agency responsible for carrying out
this function. The San Francisco Vessel Traffic System
is one of the first such systems to be put into
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NAVIGATION AIDS
service, with eventual coverage of the deep draft
waterway system of the San Francisco Port complex,
including the bay tributaries extending north and east
to Sacramento and Stockton, south to Redwood City, and
seaward approximately 20 miles.
The San Francisco system incorporates the functions of
the Coast Guard experimental facility formerly known as
Harbor Advisory Radar (HAR). The Vessel Traffic
Center, operated continuously by Coast Guard personnel,
maintains communications with vessels via vhf f-m
radiotelephone and monitors the position and movements
of larger vessels by shorebased radars and position
reports. A traffic separation scheme is now being
implemented to separate vessels traveling in opposite
or nearly opposite directions. Future developments
will include a Coast Guard operated Vessel Movement
Reporting System for the Sacramento and San Joaquin
Rivers, and a navigational safety summary broadcast,
similar to present weather reports, primarily for the
benefit of small vessels.
The Vessel Traffic System is a voluntary system of vhf
voice communications used in conjunction with a high-
resolution radar surveillance system and computer to
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NAVIGATION AIDS
track traffic in and out of the San Francisco Bay. The
system is used out to 8.8 miles, and operation is
similar to an air traffic control system. The Coast
Guard operator identifies a target on the radar through
voice contact; he then enters the data into a computer
which stores the information and tracks the vessel
through the bay. The primary purpose of the system, is
safety. It is a pilot program for several nationwide
systems. Presently, Puget Sound maintains a voice-only
operation while New York, New Orleans, Houston,
Chesapeake, and Delaware are in the planning stages for
voice and radar systems. The San Francisco system will
use two radars, one at Yorba Buena Island, which would
be the "Vessel Traffic Center", the other at Point
Bonita. VHF radios will be located at Point Bonita,
Concord, and Yorba Buena Island. Radios will operate
on vhf f-m Channels 13, 16, 18, and 21. The radar
system was designed and supplied by Airborne Instrument
Labs with Motorola supplying the microwave inter links.
An existing Coast Guard computer will be utilized with
special programming by APL, Johns Hopkins. The radars
are of a special design for the Coast Guard and feature
horizontal, vertical, or circular polarization and
digital output. The computer will store seven basic
charts of the Bay area, which will be displayed to the
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NAVIGATION AIDS
operator on 17-inch CRTs for easy identification and
tracking. When a ship is logged into the system, it is
identified by pilot name, name of the ship, ship
registration number. Coast Guard assigned number, and
destination. Information is then stored and the ship
is tracked to its destination, in port or to sea,
automatically. Provision has been made for automatic
handoff from radar to radar to the computer. The radar
display is photographed every three minutes for
permanent records. This system is meant for use with
large ships; pleasure craft are not to be included at
this time, although the system has sufficient
resolution. There are presently no plans for
implementing radar transponders aboard the vessels,
although it has been considered.
It appears that this system is an excellent candidate
for control of offshore dumping out to 20 or 40 miles
depending on the elevation of the radar transmitters.
The addition of a radar transponder, with auxiliary
sensor inputs to indicate the time of dump, would make
up a complete monitoring system. This type of
transponder is presently under development. Also,
since plans are being made to implement this system in
New York, New Orleans, Houston, Chesapeake, and
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NAVIGATION AIDS
Delaware, the majority of the major dump sites will be
covered.
§li§iiiiS- ~ Tne Navy Navigation Satellite System
(NNSS) is a worldwide all-weather system from which
accurate navigational position fixes can be obtained
using the data transmitted from five orbiting
satellites, four tracking stations, two injection
stations, the U. S. Naval Observatory, and a computing
center. Any number of user navigational installations
can exist with no interference between them. The
navigation satellites are placed in circular polar
orbits about earth at an altitude of approximately 600
nautical miles. The orbital planes of the satellites
have a common point along the earth's rotational axis.
Each satellite orbits the earth approximately every 107
minutes. The geometrical placement of the orbiting
satellite allows an earth-bound observer to cross
directly under the satellite twice daily. Typically,
the observer receives data from the satellite twice
each time he is near the orbit, because the satellites
appear to traverse longitudinally as the earth rotates.
The earth rotates 27° longitudinally per satellite
pass. At the equator, about 20 daily fixes are
possible. Realistically, about 15 daily fixes can be
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NAVIGATION AIDS
realized. In Los Angeles (34° latitude) an average of
about 29 passes is observed daily, of which
approximately 20 provide usable fixes. The utilization
of the satellite data to compute a position fix is
similar in concept to any hyperbolic positioning system
where the satellite simulates the multiple transmitting
stations by its inherent motion relative to the user.
The shipboard equipment required to use the NNSS
consists of an antenna, preamplifier, satellite
receiver, computer, and teleprinter. This equipment
must be installed in an environmentally controlled
area. A position fix using this system permits
latitude and longitude on a worldwide, all-weather
basis to an accuracy of 40 meters from a single
satellite pass. Because satellite passes are available
on a 1 to 2 hour interval, dead reckoning between
satellite passes, using manual or electrical inputs
from the ships speed and heading sensors, is required.
A typical shipboard installation of this system will
cost between $30,000 and $65,000.
c. Raydist - The Raydist radio navigation system is a
proprietary product of the Hastings Raydist Company.
Two basic Raydist systems can be considered. They are
the DR-S which is an active system utilizing a mobile
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or shipboard transmitter, and the Raydist T which is a
passive system utilizing four shorebased systems. The
Raydist system generates dual hyperbolic/hallop
coordinate geometries which provide a high degree of
operational flexibility and simplicity. A sensitivity
of 1.5 feet at a geographic position accuracy of better
than 10 feet make Raydist suited to applications
ranging from general navigation to precision
electronics survey. Presently, only one Raydist system
is in continuous operation; it is located in the lower
Chesapeake Bay area and provides coverage in the
Chesapeake Bay and Virginia continental shelf. This
system is sponsored by the State of Virginia. The
system is currently under evaluation by several
organizations, including the Virginia Marine Resources
Commission, Virginia Institute of Marine Science, and
the U.S. Coast and Geodetic Survey. The Raydist system
can be used out to 150 miles without losing its
accuracy. Operationally, a CW signal at approximately
3 MHz is transmitted from the vessel. A reference
signal is simultaneously generated at the shore station
at a frequency equal to one-half the mobile
transmitters carrier frequency, plus or minus 200 Hz.
The shore station reference frequency is doubled and
heterodyned with the received signal from the mobile
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transmitter (ship) to obtain an audio beat note of
approximately 400 Hz. To obtain red range, the audio
tone generated at the red base station is returned to
the mobile installation together with the base station
reference signal. This is done with minimum use of
frequency spectrum by incorporating the audio tone as
single sideband modulation on the base station
reference carrier. The audio tone information is
extracted from the received signal on the vessel, and
the base station reference is again doubled and
heterodyned with the mobile CW signal within the
navigator. This locally generated audio tone has
precisely the same frequency as the one derived at the
base station, and the two tones exhibit a phase
relationship proportional to distance between the
vessel and the base station. The two audio tones are
then applied to a precision electromechanical phase
meter to obtain red range. This process is repeated
with the green shore station to obtain the green range
coordinate. In the Raydist-T configuration, the CW
mobile transmitter is placed ashore, establishing a
baseline with respect to the red shore transmitter.
For optimum coordinate geometry, a second CW
transmitter is positioned to form a baseline with the
green base station so the four stations form an
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approximate rectangle. The resulting independent
hyperbolic baselines provide an easy-to-interpret
hyperbolic geometry. Three independent lines of
position are available from the four-station
arrangement, providing a convenient means for automatic
or manual lane identification. This feature can be
used for lane determination by ships approaching
outside the coverage area. The Raydist signals are
completely continuous and tracking response can be made
extremely fast permitting the systems use in high
performance aircraft and rapidly maneuvering vessels
with negligible accuracy degradation. The major
drawback of this system is the limited number of
installations in the U.S. This system, however, is
available for lease anywhere in the world.
d. VLF Area Navigation Ontrac II is the trade name of a
receiving/computing (RNAV) system manufactured by
Communications Components Corporation of Costa Mesa,
California, which uses existing vlf navigation and
communication transmitters providing worldwide
navigation. The basic principle of operation is that
all vlf stations are phase stable and can be used to
generate hyperbolic lines of position, which the built-
in computer converts to latitude/longitude. Unlike
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Omega, which utilizes phase-synchronized transmitters,
this system measures the phase difference at the
beginning of a run and stores the information in
memory. Six receivers are operated simultaneously,
allowing automatic selection of the best three signals.
A built-in minicomputer looks at the phase difference
(arrival times) and displays the changes in
latitude/longitude and speed as the vessel is underway.
»
To use the system, the operator must enter (through a
small keyboard) his point of departure
latitude/longitude in degrees, minutes, and seconds;
date; time; destination latitude/longitude; and any
way-points he may desire. The unit then displays
latitude/longitude of his present position; heading and
distance to destinations (five way points); speed and
time to destination; time (GMT) ; and left/right track.
All of these displays are available as external
outputs. Special tables and charts are not required to
operate this system to its stated accuracy of 1200
feet. Another feature of this device is a dead-
reckoning mode. Because the device has its own
computer and memory, it is able to remember its last
position and, in the event of a complete loss of
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signal, will continue to compute heading, position, and
speed based on its last known inputs.
At the time of this writing, the system is just going
into production. Its prime purpose is the replacement
of inertial navigation in small jet aircraft.
The selling price of the system is estimated to be
under $20K. The unit is small in size, operates from
24 VDC, and requires no special installation. From
present information, this system is a strong candidate
for navigation/control of the dumping vessels.
2.10 SUMMARY
In brief summary, the existing level of documentary monitoring of
operational practices of ocean disposal is inadequate for the
number and scope of disposal operations.
In connection with regulatory monitoring, present inspection of
disposal operations is inadequate. To correct this situation, an
improvement in monitoring by means of an automatic, tamper-proof
vessel log similar to that used by airlines and trucking firms
should be considered.
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The synthesis and evaluation of candidate automatic regulatory
dump monitoring systems requires a comprehensive understanding of
present operational dumping practices and detailed information
and characteristics of electronic navigation techniques as well
as of the dump vessels themselves, including vessel berth
locations, speed, range, dump control specifics, and
communication equipments. Additional factors to be considered
include dump vessel traffic, type of dump material, existing
shore facilities and personnel, and owner/captain cooperation.
An operational automatic vessel monitoring system must rely
heavily on existing electronic navigation systems because it must
integrate this position information with other events such as
time of day, time of dump, duration of dump, and water depth.
2-22 446OC1629
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Section 3
BIBLIOGRAPHY
Interstate Electronics Corporation
AN ATLAS OF OCEAN WASTE DISPOSAL SITES
Report 446OC1545
September, 1973
Nathaniel Bowditch
AMERICAN PRACTICAL NAVIGATOR
H.O. Publication No. 9
U.S. Government Printing Office
Washington, DC
U.S. Naval Observatory
THE NAUTICAL ALMANAC
U.S. Government Printing Office
Washington, DC
Defense Mapping Agency
NAUTICAL CHART SYMBOLS AND ABBREVIATIONS
Chart No. 1
National Ocean Survey
Washington, DC
U.S. Department of Commerce, ESSA, Coast and Geodetic Survey
C&GS NAUTICAL CHARTS FOR SAFE NAVIGATION(Pamphlet)
U.S. Government Printing Office
Washington, DC
U.S. Department of Commerce, National Ocean Survey
PUBLICATION FOR SAFE NAVIGATION(Pamphlet)
U.S. Government Printing Office
Washington, DC
U.S. Department of Transportation, U.S. Coast Guard
THE SKIPPERS COURSE
Publication No. CG-433
U.S. Government Printing Office
Washington, DC
4460C1629
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BIBLIOGRAPHY
U.S. Department of Commerce, ESSA, Coast and Geodetic Survey
UNITED STATES COAST PILOT
National Ocean Survey
Washington, DC
The Institute of Navigation
NAVIGATION (Quarterly)
Washington, DC
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Documents prepared by Interstate Electronics Corporation,
Environmental Engineering Division, under contract 68-01-0796 for
the U.S. Environmental Protection Agency, Ocean Disposal Program,
are:
OCEAN WASTE DISPOSAL IN SELECTED GEOGRAPHIC AREAS
Report No. 446OC1541
August, 1973
*PB 224 793/AS, $8.00 paper, $1.45 MF
A BIBLIOGRAPHY ON OCEAN WASTE DISPOSAL
Report No. 446OC1542
May, 1973
*PB 224 452/AS, $4.25 paper, $1.45 MF
DIRECTORY OF MANAGERS, ENGINEERS AND SCIENTISTS IN OCEAN
WASTE DISPOSAL AND RELATED ENVIRONMENTAL SCIENCE FIELDS
Report No. 446OC1543
August, 1973
*PB 224 459/AS, $3.50 paper, $1.45 MF
GUIDELINES FOR DEVELOPMENT OF CRITERIA FOR CONTROL OF
OCEAN WASTE DISPOSAL
Report No. 446OC1544
September, 1973
AH ATLAS OF OCEAN WASTE DISPOSAL SITES
Report No. 446OC1545
September, 1973
OCEAN WASTE DISPOSAL IN THE NEW YORK BIGHT
Report No. 446OC1559
August, 1973
*PB 224 983/7AS, $4.50 paper, $1.45 MF
OCEAN WASTE DISPOSAL PRACTICES IN METROPOLITAN
AREAS OF CALIFORNIA
Report No. 446OC1635
February, 1974
*These reports are available through the National Technical
Information System, U.S. Department of Commerce, Springfield,
Virginia 22151.
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