EPA-R2-73-243
September 1973
Environmental Protection Technology Series
Aerial Spill Prevention Surveillance
During Sub-Optimum Weather
Office of Research and Development
U.S. Environmental Protection Agency
Washington, D.C. 20460
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and
Monitoring, Environmental Protection Agency, have
been grouped into five series. These five broad
categories were established to facilitate further
development and application of environmental
technology. Elimination of traditional grouping
was consciously planned to foster technology
transfer and a maximum interface in related
fields. The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL
PROTECTION TECHNOLOGY series. This series
describes research performed to develop and
demonstrate instrumentation, equipment and
methodology to repair or prevent environmental
degradation from point and non-point sources of
pollution. This work provides the new or improved
technology required for the control and treatment
of pollution sources to meet environmental quality
standards.
-------
EPA-R2-73-243
September 1973
AERIAL SPILL PREVENTION SURVEILLANCE
DURING SUB-OPTIMUM WEATHER
By
Robin I. Welch
Allan D. Marmelstein
Paul M. Maughan
Contract No. 68-01-0191
Program Element 1BB041
Project Officer
John Riley
Office of Water Programs Operations
Environmental Protection Agency
Washington, D.C. 20460
Prepared for
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
For sale by the Superintendent of Documents, U.S. Government Printing Office
Washington, D.C. 20402 - Price $1.40
Stock Number 5501-00709
-------
EPA Review Notice
This report has been reviewed by the Environmental
Protection Agency and approved for publication.
Approval does not signify that the contents neces-
sarily reflect the views and policies of the
Environmental Protection Agency, nor does mention
of trade names or commercial products constitute
endorsement or recommendatton for use.
ii
-------
ABSTRACT
Multi-band aerial photography was acquired during specified
conditions of cloud cover and reduced visibility considered to be
representative of a nearly infinite range of sub-optimum weather
conditions. (For aerial photography, optimum is defined as clear
skies and greater than 15 miles visibility). Basic techniques were
derived from an earlier project which defined a system for strategic
spill prevention surveillance (Welch, et al. 1972).
Results of this project indicated that only one film tested,
a high sensitivity color positive film, provided consistently
interpretable results. Rapid access techniques were also evaluated
leading to recommendations for a tactical system which provide for
both real-time and near real-time system update during sub-optimum
aerial photographic conditions.
-------
CONTENTS
Section Page
I Conclusions 1
II Recommendations 3
III Introduction 8
IV Methods 10
V Results 23
VI Acknowledgements 34
VII References 35
VIII Appendix 1 36
-------
FIGURES
No. Page
1 AVON SUB-SITE 13
2 RICHMOND NAVY DOCK SUB-SITE 14
3 RICHMOND SCRAP STEEL YARD SUB-SITE 15
4 TEST PHOTOGRAPHY 27
5 TEST PHOTOGRAPHY 29
6 TEST PHOTOGRAPHY 31
VI
-------
TABLES
No. Page
1 Weather Types Selected for Investigation n
2 Interpretation Criteria Utilized 20
by Interpreters
3 Summary Results 24
vii
-------
SECTION I
CONCLUSIONS
TACTICAL UPDATING FOR AERIAL SURVEILLANCE SPILL PREVENTION
CAN BE SUCCESSFULLY ACCOMPLISHED DURING SUB-OPTIMUM WEATHER
CONDITIONS UTILIZING CONVENTIONAL COLOR FILM.
In comparison to the other film/filter combinations tested,
only Kodak SO-397 positive color film (exposed through a Wratten
1A filter) provided adequate image quality regardless of time of
coverage, weather conditions, or reasonable deviation from optimum
exposure settings. In fact, film apparently can be utilized under
any daylight conditions where an aerial photographic mission can be
safely attempted. The latitude of this film combined with compre-
hensive flight planning adds the necessary tactical dimension needed
to maintain a dynamic information file based on the strategic sur-
veillance system specified in Welch et al. (1972). Color infrared and
black and white panchromatic films which have specified surveillance
applications in clear weather exhibited shortcomings which warrant
recommendation against their use under less than optimum weather.
CAREFUL FLIGHT PLANNING AND COMPREHENSIVE WEATHER MONITORING
ARE ABSOLUTE REQUIREMENTS FOR SUCCESSFUL MISSION PERFORMANCE.
Constraints on both the photographic system and on aircraft
operations are more severe under less than optimum weather conditions.
The pilot has to consider ceiling height and horizontal visibility as
well as aircraft speed in order to successfully obtain low altitude
photography. As altitude decreases image motion increases unless there
is a compensating decrease in aircraft speed. Aircraft safety must be
a major consideration in mission planning, its impact depending to a
limited extent on the urgency of the mission.
Careful planning by the photographer is also required. To insure
correctly exposed film and maximum possible data content, his planning
should be based on a reliable source of weather information. Clouds,
suspended particulates, precipitation, shadows and non-uniform illumi-
nation all require careful consideration, along with the usual factors
of target characteristics and product requirements.
The importance of weather to the safety and performance of the
photographic mission necessitates a source of timely, accurate weather
information.* Both forecasted and observed conditions for the target
vicinity as well as the routes of ingress and egress should be avail-
able. FAA flight service facilities along the flight path provide a
good source of enroute weather. For weather over the target the ideal
-------
source is an on-site observer in radio contact with the aircraft.
Comprehensive weather information will help both pilot and photo-
grapher to perform their respective jobs effectively.
A SINGLE ENGINE, HIGH WING AIRCRAFT CARRYING A HIGH RESOLUTION
CAMERA SYSTEM OF FORMAT SIZE CONSISTENT WITH AREAL COVERAGE REQUIRE-
MENTS OFFERS MAXIMUM VERSATILITY.
The preferred vehicle for use under less than optimum weather
conditions is a single-engine, high-wing monoplane carrying in
vertical mode an aerial camera of format size suitable to the desired
areal coverage. Single engine monoplanes are capable of the low
altitude, low speed operation necessitated by operation under low
clouds. The high-wing configuration is preferred because it simplifies
the problem of visually alighning the aircraft on a predetermined
flight line. An acquisition scale of 1:5000 provides adequate detail
provided a high quality camera system is chosen.
AN INTEGRATED RAPID ACCESS SYSTEM CAN PROVIDE USEFUL REAL-TIME
TACTICAL INFORMATION.
In situations requiring real-time or near real-time assessment
of ephemeral conditions, such as natural disasters or catastophic
spills, a properly employed rapid access photographic system can meet
most information requirements which could be addressed in a routine
situation by aerial photography. A rapid access operation requires
coordination in all phases, but can significantly reduce the elapsed
time between exposure and information dissemination. Major time
reductions can be accomplished by collating the film processing,
interpretation, and dissemination facilities and if possible, by
overlapping processing and transport functions.
-------
SECTION II
RECOMMENDATIONS
Film/Filter Combinations
In that aerial color film exposed through a 1A filter was the
only film/filter combination which produced consistently interpre-
table results, it is recommended that a film of this sensitivity,
color rendition, and latitude be used exclusively for tactically
updating spill surveillance photography during sub-optimum atmospheric
conditions. \\
It is recommended that a high qualify photographic light meter
be used by the aerial photographer to determine desired exposure.
In order to calculate basic exposures, the meter should be aimed at
an average subject in the ground scene during an initial pass over
the target. In cases where important detail is located in darker than
average areas, an increase in exposure of one "f" stop is recommended.
It is recommended that the aerial photographer develop a list of
acceptable exposures for a variety of scenes and illumination conditions
based on his experience with a particular camera-film-filter combination,
By combining experience and light meter readings he will be able to
consistently make exposures of acceptable quality.
The basic exposures used in this investigation and recommended for
SO-397/1A are as follows:
Cloud Cover Exposure
Clear 1/500 f 10
Scattered 1/500 f 8
Broken 1/500 f 6.3
Overcast 1/500 f 3.5
Where a need exists for rapid access to the data available from aerial
photography it is recommended that a panchromatic film such as Kodak
Plus X Type 2402 also be employed. This film can be readily processed,
either during' the mission or immediately upon landing, using portable
equipment. The process utilized, as discussed below, yields both a
negative for archiving and a positive transparency for immediate in-
terpretation.
-------
Film Processing
No special film processing is required for photography acquired
during sub-optimum weather. Thus, conventional equipment and chemicals
are recommended for processing the aerial photography so obtained.
For rapid access film processing, it is recommended that aerial
color film be processed in conventional fashion using a continuous roll
film processor. The special arrangements necessary for processing
film immediately on delivery to the processing facility must be an
integral part of planning for a rapid access capability.
It is recommended that the panchromatic film used for rapid access
purposes be processed by the Bimat method. This method is a diffusion
transfer development where an imbibed non-light-sensitive film is mated
emulsion to emulsion with an exposed black-and-white film in a light-
tight processor. After prescribed development time, the two fully
processed films are separated with the original film becoming a negative
and the Bimat film a positive. Because the development is self-
limiting, time of processing beyond the minimum is not critical.
Both films are damp and susceptible to emulsion scratching if not
dried carefully or the emulsion covered with a clear plastic cover sheet
made for this purpose. Thus for archival storage it is recommended that
both films be washed in running water for 10 minutes and dried carefully
to prevent staining. Either film can be used without washing for several
days but staining will occur after that time.
Several Bimat processors are available, each having some special
characteristics. The unit used in this investigation, a Mark System,
Incorporated Model 320 Bimat processor, was completely portable and manu-
ally operated and is recommended for these reasons.
Vehicle Considerations
Aircraft safety and maneuverability become critical when
adverse weather conditions impose low flying speeds (80-100 knots).
If an aircraft must fly at a low altitude to stay below clouds (per-
haps 800-1000 feet above terrain), the plane must be flown at a low
enough speed to permit camera cycling between exposures and to prevent
image motion during exposure. It is therefore recommended that only
those single-engine and light twin-engine aircraft capable of such
performance be considered. Many heavier twin-engine and larger air-
craft cannpt be flown safely under the specified conditions.
-------
Interpretation Equipment
In an operational system it is recommended that zoom stereo-
scopes be employed whenever possible, as they permit a more detailed
interpretation due to the zoom capability and high resolution. Zoom
stereoscopes also produce less eye fatigue and thus increase inter-
preter efficiency.
Simple stereoscopes are adequate for examination of good quality
photography and are more practical for field interpretation as neces-
sitated by a rapid access requirement.
General Considerations
Sub-Optimum Atmospheric Conditions - A carefully planned flight is
essential to the smooth functioning of an aerial surveillance mission.
Preparation on the ground prevents most in-flight distractions and un-
necessary flight delays.
The data requestor must define his information requirements com-
pletely and accurately for the flight crew. Such data should include
the following information:
Mission Timing - Aerial photographic missions should be flown with the
sun angle at greater than 30° above the horizon to provide adequate il-
lumination. Unless dynamic ground conditions, weather factors or urgent
need for data dictate that photographs will be made at other times, this
constraint is recommended.
Scale of Coverage - Aerial photography for spill prevention surveil-
lance under adverse weather conditions should be acquired at a scale
of about 1/5,000. Smaller scale photographs acquired at higher altitudes
are often degraded by haze and cloud cover. Larger scales, which require
an increased number of photographs to cover the target, are usually not
necessary for detailed image interpretation.
Flight Line Direction - For most applications it is recommended that
flight lines run parallel to the prevailing terrain or to the major axis
of the area to be photographed. If no definite trend exists for features
o-Mnterest, north-south flight lines should be specified.
Flight planners for aerial photogrpahic missions commonly use seven
and one half or fifteen minute U.S. Geological Survey topographic quad-
rangle sheets for flight line plots. These maps are recommended for
plotting bdth flight line location and orientation and for the post-
mission plotting of areas covered by the resultant photography. For
-------
the purpose of tactical updating as detailed herein, reference should
be also made to target information previously produced by the strate-
gic spill prevention survey which presumably would have been conducted
over most areas of interest.
Overlap and Sidelap Requirements - For stereoscopic viewing sixty
percent forward lap between successive exposures and thirty percent
sidelap between parallel flight lines are standard requirements.
Rapid Access Mission Considerations
A true rapid access system must provide support in every phase of
data acquisition from flight planning through delivery of finished in-
formation, graphics and documentation. If extended delays occur at any
time during the operation due to inadequate scheduling or preparation,
time saved by many of the other rapid access techniques may be negated.
For example, if film processing time can be reduced from four hours to
one hour but the necessary trained photointerpreters are not available
until the following day, then no real advantage has resulted from rapid
film processing. Thus, each phase must not only be carefully planned
and executed but must be well interpreted with all other phases in
order to enjoy the real benefits of rapid access.
It is recommended for rapid access missions that a set of instruc-
tions and a comprehensive check list such as that shown below covering
equipment requirements, functions of various staff members, arrangements
for outside services and delivery of finished information, be prepared
and carefully followed.
RAPID ACCESS CHECK LIST
Mission Plan
Aircraft
Cameras
Film
Accessories
Flight Operations
Crew
Camera System
Flight Plan
Aircraft and System Check
Weather Briefing
Maps
-------
Enroute
Target
Film Processing
Laboratory Alerted
Bimat Processor and Materials
Courier for Film
Film Editor Alerted
Interpretation Operations
Facility Available
Portable Light Table
Stereoscope
Projector
Screen
Personnel
Map Sheets
References
Data Sheets
-------
SECTION III
INTRODUCTION
The primary objective of this project was to determine the ex-
tent to which various kinds of aerial photography, when acquired of
necessity under adverse weather conditions, could be used to locate
and identify potential sources of spills of oil and other hazardous
material. It is widely recognized that aerial photography, flown to
strict specifications, can quickly and economically provide vital
information on the location, qualtity and quality of various com-
ponents of the natural environment. In a previous project (Welch,
et al., 1972) it was shown that aerial photography could be used to
identify potential sources of environmental damage from accidental
spills of oil and hazardous materials, and that such information could
be used in spill prevention.
The previous project demonstrated that high altitude color in-
frared photographs taken at scales of 1/40,000 to 1/60,000 were useful
in regional surveys for locating industrial activities that could be ex-
pected to produce spills of oil and other hazardous materials. After
these areas have been delineated on small scale photographs, color
aerial photography flown at larger scales of 1/5,000 to 1/10,000 can be
taken of selected areas for more detailed analysis in order to locate
specific potential threats and actual spills of these materials.
Strategic information gained in this manner could be used to prevent
spills by early detection of careless practices which lead to undesirable
releases of oil and hazardous materials into waterways. Furthermore,
quick action by an organized force using accurate data on the location,
extent and direction of spread of a spill can greatly reduce the harmful
effects of such an event. It is frequently the case that circumstances
mediating a tactical approach combine to present an update problem at
a time when atmospheric conditions are not conducive to aerial photo-
graphy. For example, an extended heavy rainfall could produce flooding
and soil saturation, jeopardizing earthen revetments. Such a protracted
storm is also likely to result in residual cloud cover, necessitating a
delay in updating unless specific procedures for such an eventuality have
been previously defined.
If the weather factors restricting the acquisition of aerial photo-
graphy are known and if methods to overcome and control these factors
are understood, it is possible to increase the time during which aerial
photography can be obtained successfully and thus provide an even more
valuable data acquisition tool for use by resource managers.
8
-------
Existing camera systems, films, filters, and processing and
interpretation techniques can be manipulated in a variety of ways to
provide acceptable photography under various lighting conditions. In
investigating these methods for use in spill prevention, it was hypo-
thesized that even in critical situations where weather was not ideal,
acceptable aerial photography could be obtained.
This study was undertaken to provide a means for acquiring high
quality information for spill prevention under a variety of sub-
optimum aerial photographic weather conditions. Optimum conditions
are taken to be clear skies with at least 15 miles horizontal visi-
bility. Thus, the term "sub-optimum weather conditions" applies to
any situation resulting in sky cover (clouds) or reduced visibility.
In addition, several rapid access techniques useful for minimizing
the time necessary for acquisition and dissemination of useful in-
formation were investigated.
-------
SECTION IV
METHODS
Weather-Type Selection
Cloud and haze conditions under which aerial photographic
surveillance was to be attempted were chosen so as to be represen-
tative of conditions which commonly occur over industrial areas.
Weather parameters considered were divided into two categories
clouds and haze each of which offers different problems in
acquisition of high quality photography. For purposes of discussion,
haze is considered to describe a general set of circumstances resulting
in decreased horizontal visibility due to smoke, dust, photo-chemical
smog or other particulates, but differing from, although frequently
occurring with clouds. Further, interaction between sun angle (angle
above horizon) and haze was analyzed because the effective path length
of the illuminating source (a function of angle above the horizon) is
critical in selecting photographic parameters. In heavy haze, the
difference of a few hours) may allow considerable more flexibility in
photo acquisition.
Table 1 summarizes the cloud and visibility conditions chosen
for analysis. These conditions were considered representative incre-
ments of weather conditions which vary continuously over a nearly
infinite range. The increments specified were utilized as data acqui-
sition guidelines in attempting to analyze the effects of combinations
of the weather types listed on interpretability of ground features.
Test Site Selection
The existence of numerous aerial photography previously obtained
of sites in the San Francisco Bay Area under near-optimum conditions
(as part of the original aerial surveillance spill prevention project)
suggested the continued use of certain of these same sites for the
present project. An analysis of meteorological records for the Bay
Area revealed that the chosen meteorological conditions occurred
there with sufficient frequency to permit the project to be success-;
fully completed within a reasonable period. For example, through the
use of statistics available from the National Weather Service for the
period 1948-1965, the following description of the test area was
derived at the outset:
"Smoke and/or haze was reported daily at least
10
-------
TABLE 1
WEATHER TYPES SELECTED FOR INVESTIGATION
(X = example obtained)
(E = no example obtained)
Cloud Base (height in feet)
Sky Cover (amount in tenths) 1,000 5,000 10,000 20,000+
Overcast (10) XXX X
Broken (5-9) XXX X
Scattered (1-4) X X X X
Sun Angle
Haze Type (visibility in
miles) 20° 40° 60°
Medium (2-4) XXX
Heavy (^2) X XX
11
-------
50% of the time from October to January, but
less than 2Q% of the time from March to August.
°The ceiling was less than 20,000 approximately
30% of the time during June, July, and August.
°During these same months the mean sky cover
(in tenths) was approximately 3.5.
Test areas previously utilized were chosen for continued over-
flight during this program. These areas, and the reasons for their
selection, were:
°Avon Refinery
The complex of unrevetted storage tanks and pipe-
lines lying adjacent to Pacheco Creek (Figure 1) in
the center of the refinery area was designated the
prime target area. The complex nature of this pipe-
line array provided an excellent permanent feature for
analysis of portrayal on the film/filter combinations
specified.
"Richmond Navy Dock
The holding pond for oily bilge wastes located at
the Navy fuel oil transshipment dock (Figure 2) was
chosen as a sub-area for this project as it is a
dependable site for imaging oil on water. It also
represents one of the most important types of hazard
(oil waste holding pond situated in an area of high
rainfall runoff) juxtaposed to a waterway that the
surveillance system should be designed to detect.
OO4
Richmond Scrap Steel Yard
The scrap steel yard at Richmond (Figure 3) was
also selected as it represented a continual, complex
source of hazardous materials entering San Francisco
Bay. The large accumulation of materials also provides
a dynamic site for detail analysis.
System Selection
Cameras
A basic requirement for aerial cameras considered for this study
12
-------
FIGURE 1. AVON SUB-SITE AND FLIGHTLINE
13
-------
PI
FIGURE 2. RICHMOND NAVY DOCK SUB-SITE AND FLIGHTLINE
14
-------
i \RESERV\E °
A \ o
»SHIPYARD Piling
J-
&FF3Z!:
' .- .:: :^-:::--.---^-::-:-^::,
"":;'v;:;;C;:r;V;:::^
Pile«
FIGURE 3. RICHMOND SCRAP STEEL YARD SUB-SITE AND FLIGHTLINE
15
-------
was that lens quality and shutter performance be adequate to take
photographs under restricted lighting conditions during daylight hours.
The Hasselblad 500 EL camera, with 80 mm., f 2.8 lens was known to be
ideal for this requirement. Based on the film/filter combinations
selected, a three-camera array was set up for this investigation. In
addition, two 35 mm. Nikon cameras were chosen for hand-held oblique
and vertical operation to provide additional coverage for documenta-
tion and personnel briefing.
Films and Filters
Several films and filters were considered preparatory to this
study. It was shown in the previous study that two films were par-
ticularly suitable for aerial surveillance in spill prevention. The
first is Kodak film type SO-397, a high sensitivity (ASA 160) aerial
color film with excellent exposure latitude. It has the ability to
record features displaying a range of illumination (for example bright
sun and shadow) with acceptable color fidelity. The second is Kodak
Aerochrome Infrared, film type 2443, a false color, infrared sensitive
film with relatively high sensitivity (approximate ASA 100).
In addition, a black-and-white panchromatic film was made to
serve as a control for comparison with color films and because sen-
sitivities even higher than those of color films are available in such
films. Therefore, Kodak Plus X 2402 (ASA 400) and Panatomic -X 3400
(ASA 200 when Bimat processed) films were selected.
A Wratten 1A filter was used with aerial color film (color/A)
to reduce the blueish cast caused by atmospheric haze. A Wratten
12 filter was used with Aerochrome Infrared (color 1R/12) as speci-
fied by the manufacturer in order to prevent exposure in the blue
portion of the spectrum. With black-and-white film no filter was
used in order to fully utilize the capability of the film to image
under low light level conditions.
Exposures
The basic exposures used in this investigation were:
Film-Filter Types
Cloud Cover SO-397/1A 2443/12 3400/no filter
(Bimat Processed)
Clear 1/500 f 10 1/500 f 6.3 1/500 f 11
Scattered 1/500 f 8 1/500 f 5.6 1/500 f 10
Broken 1/500 f 6.3 1/500 f 3.5 1/500 f 8
Overcast 1/500 f 3.5 1/500 f 2.8 1/500 f 4
16
-------
These exposure values varied depending upon height and density
of clouds and haze conditions associated with them. Variations were
made in accordance with meter readings obtianed from a downward
pointing photographic light meter.
Film Processing
A commercial, photographic processing firm was employed for
developing the films used in this investigation. The firms chosen
used a Kodak Type 1411 continuous processor. Special arrangements
made prior to the rapid access exercise permitted the color film from
that mission to be processed without delay.
For rapid access techniques using black-and-white films and Kodak
Bimat material, a Mark Systems Processor No. 230 was used. The Kodak
Bimat material utilizes a diffusion transfer process whereby a non-
light-sensitive film (Bimat film) is pre-imbibed in a single processing
solution (Bimat imbibing chemicals) prior to mating with the exposed
black-and-white film (Panatomic-X). If stored at 35° to 45° F., the
Bimat film may be pre-imbibed and preserved for weeks. The two films
are mated emulsion to emulsion in total darkness while being wound onto
a holding spoon.
After a short time (five minutes for Panatomic-X film) the self-
limiting processing is completed and the two films one a positive
and one a negative can be separated and either plastic laminated and
viewed immediately or washed and dried for later viewing. The Bimat
processor described is completely portable, requiring no electricity.
A dark film changing bag is required only if one wishes to rethread the
film cassettes after exposure, or as a safety factor in the event film
is completely wound into the cassette after exposure.
Aircraft
The Cessna 206 photographic aircraft used in this study proved
to be a very versatile aircraft for obtaining spill prevention photo-
graphy. The aircraft can be flown safely at low speeds (as slow as
80 kts.) and at low altitude, which are occasionally required under
adverse weather conditions. Th,is aircraft also meets the stability and
maneuverability requirements for photographic overpasses, as well as
providing pilot visibility forward and downward for proper flight line
navigation.
Interpretation Equipment
Conventional stereoscopic viewing equipment was used for inter-
preting images obtained in this study. Levels of magnification from
17
-------
2X to SOX were used to evaluate the detectability of fine image detail.
A dual strand light table was used to permit simultaneous viewing of
two 70 mm. film strips for comparison of photo quality.
Ground Truth Design
Ground truth, collateral information derived from sources other
than the imagery currently under interpretation, is a necessary adjunct
to image interpretation. The degree of ground truth required for a
particular interpretation depends on the nature of the imagery, skill
of the interpreter, target characteristics, and product requirements.
The philosophy of aerial surveillance is the supportive ground
truth should be minimized, with as much of the needed information as
possible being derived from image interpretation. Extensive ground
truth collection partially negates several of the advantages usually
cited for aerial surveillance: cost, timeliness, access to denied
areas, single source of data. In photointelligence operations, the
image acquisition and interpretation phases are manipulated to optimize
compatibility with product requirements and target characteristics.
In the design of the present project, need for acquisition of
additional ground truth information was minimized by design through
dependance upon the data archive available as a result of the previous
aerial spill surveillance project.
Specific Interpretation Techniques
Imagery acquired during photographic flights was annotated and
catalogued, then independently interpreted by three image inter-
preters to determine the merits of each film/filter combination under
the weather conditions selected for this test Each roll of imagery
was cut into stereo triplets (more frames were included in .those
instances where phbto scale exceeded 1:5000) covering the three selected
target areas. The best quality color /IA triplet for each scene was
subjected to a detailed interpretation under a high resolution zoom
stereoscope in order to extract the maximum available information about
features to be compared throughout the test. The features selected for
use in the test include many examples of past or potential hazards as
stated in the report by Welch, et al., 1972. Results of the detailed
interpretation plus the existing data base and weather information formed
the ground truth for the interpretation.
Most interpretation was made with 2x/4x simple stereoscopes on
conventional light tables in order to approximate the level of equipment
sophistication likely to be used with missions requiring image
acquisition under less than optimum conditions. Also, use of
18
-------
simple equipment established a minimum level of information which
might be extracted.
Three interpreters, working independently analyzed the images
in unordered sequence, rating the photographic quality of the imagery
and the interpretability of the preselected features. Interpreta-
bility was rated on a scale of one, two, three and zero. A summary
of the image rating criteria is given below.
Category Description
1 Objects of all contrasts are detectable
2 Objects of medium or higher contrast detectable
3 Only objects of high contrast detectable
0 No objects of any contrast detectable
E No example
Exposure ratings provided a means for the interpreter to express
his oninion concerning the reason for the indicated level of interpre-
tability. The basis for this response was purely subjective because
the interpreter did not know the conditions under which the imagery
was obtained. If the imagery "looked good" to him in terms of ex-
posure, latitude and sharpness, and in no way affected the interpre-
tability of the image he marked "g". However, if the imagery looked
dark or too light to him, "pi", "po" or "pc" was recorded. A summary
of exposure ratings follows:
Category Description
G Imagery of good quality; exposure, latitude sharpness
Pu Imagery poor due to underexposure
Po Imagery poor due to overexposure
PC Imagery poor even when correctly exposed; indicated
limitations inherent in film type or camera utilized.
A matrix was devised on which to record the final results of image
analysis. For each meteorological condition encountered, each film/
filter combination was paired with the eight classes of features (Table 2)
which were examined during the test. In this manner the evaluation of
each film/filter type is graphically displayed.
Consistent interpretation cirteria were defined by discussing the
appearance of each object type and how these appearances affected the
level of interpretability. For example, after discussion it was decided
that oil on water was to. be identified by:
"Presence of blue, black or rainbow colors
19
-------
TABLE 2
INTERPRETATION CRITERIA UTILIZED BY INTERPRETERS
Item of Interest
Interpretation Criteria
counting of tanks
leaks or seepage
oil on water
condition of dikes
trash and debris
eff1uents
water quality
tracing pipelines
Detection of tanks present; contrast of
detectable tanks; evaluate tank-like objects
for supportive information
Black, blue or rainbow coloration; charac-
teristic shape of oil covered area; reflectivity
Black, blue or rainbow coloration; shape of
oil covered area; obscuration of bottom or water
features, reflectivity
observed dike or earth revettment; noted re-
solvable items, (pebbles, rocks, boulders, etc.)
relief; color
Size, shape, color
Detectability of effluent, presence of out-
fall structure; size; total tone and color
contrast; diffusion rates
Ability to see beneath surface; color and tone
contrast
Size; shape; coloration; relief; allow for
probably continuity due to linear character-
istics
20
-------
"Reflection (not shadows) of clouds or
other objects
"Definitive shape
°Suppression of waves on surface
In addition, level of interpretability was to be determined by the
various types of contrast previously discussed. For example, if oil
was present and it was very black, highly reflective and stable in shape
it was considered to be of high contrast. If the oil present showed
only a gossamer blue or rainbow effect and had little definite shape
it was considered to be of low contrast. The criteria for all targets
analyzed are also shown in Table 2.
Data Acquisition During Sub-Optimum Weather
In accordance with the specific conditions listed as guidelines in
Table I, photography acquisition was initiated whenever suitable condi-
tions prevailed over one or more test areas. At these times, the
photographic flight crew acquired photography over each test area,
utilizing the flight tracks shown for each area in Figures 1 to 3.
Welch, et al. (1972) recommend a large scale (1:10,000 to 1:5,000)
for detailed analyses. The difficulties in interpretation imposed by
sub-optimum conditions prompted the use of the larger scale (1:5,000)
as the standard acquisition scale in this project. The image scale
varied substantially only when cloud ceiling necessitated flying at
less than the altitude required to produce the desired scale (1,310
feet above terrain using 80 mm. length lenses). Therefore, all imagery
was acquired at a scale of 1:5,000 or greater.
Weather conditions at time of acquisition were observed from
the photographic aircraft directly as well as through queries directed
towards local airport tower personnel. Exposure indices were determined
by use of a downward looking exposure meter.
In this manner, nearly all preselected conditions were investigated,
with the exception of sun angles of 20° and 40° during heavy haze (Table 1)
Rapid Access Experiment Design
In the performance of the rapid access experiment it was assumed
that data similar to that obtained during the sub-optimum weather phase
were needed quickly. These data could be interpretedfrom photos of
the area taken at the same scale and on the same flight line as other
parts of the*investigation.
For this exercise an automobile and driver were waiting at the
21
-------
airport to carry the color film to the processing laboratory while
the black-and-white film was processed in an office at the airport.
Rapid film processing techniques for both color and black-and-
white film were investigated, with elapsed time monitored separately
for each film to permit comparison of data access time. Manufacturer
-------
SECTION V
RESULTS
Our analysis shows that of the films tested only Kodak SO-397 film
exposed through a Wratten 1A filter consistently provided usuable
imagery under the meteorological conditions extant at the time of acqui-
sition of the test imagery. This film has a relatively high sensitivity,
ASA 160, and a wide latitude of acceptable exposure, perhaps one to one
and a half stops either side of an ideal exposure setting. This factor
provides usuable images in shadow as well as sunlit areas and in areas
of low albedo and high albedo when such contrasts appear on the same
film frame. It is recommended that Kodak SO-397 or equivalent film be
used exclusively in any operation requiring high resolution coverage
under less than optimum weather conditions.
A serious shortcoming of both panchromatic and color infrared films
is that under sub-optimum weather conditions the contrast between oil on
water and unpolluted water is decreased, and with degradation of weather
differentiation between water with and without floating oil becomes im-
possible. Since oil is a hazardous substance commonly introduced into
waterways, the inability to monitor its presence is a serious drawback
in a spill monitoring and prevention program.
Panchromatic film suffers a general loss of contrast as the weather
degrades. This decreased contrast particularly hinders the analysis of
dike and revetment conditions and interpretation of small, low contrast
objects such as pipes and debris.
Table 3 shows selected results from the interpretation testing.
The results presented are only a representative sample of the complete
test results shown in the Appendix. Selected images from these film
strips have been used to illustrate this report. This was done in order
to facilitate comparison of photographic characteristics and interpreter
performance. The table presents the judgment of three interpreters for
each film type, area and characteristic of interest. This array indica-
tes absolute results and interpreter consistency, which determines the
validity of the absolute results. Interpreter consistency is fairly
high, especially when one compares trend; however, the responses vary
somewhat, a problem which always arises when several interpreters, all
having different backgrounds and training, are employed.
Since the interpreters are qualitatively uniform in their responses,
the interpretability of the various film/filter combinations can be
evaluated.
23
-------
Actual Weather Frame Film
Conditions No. Type
Clear
Light
1000'
Haze
Over-
cast with
Light
1200'
Rain
Over-
cast with
Drizzle
5000'
cast
Light
Over-
with
: Rain
10-6,7,8 Color
CIR.
9-9,10, Color
11 CIR
Pan
4-42,43, Color
44 CIR
Pan
1-44,45, Color
46 CIR
Pan
7-6,7,8 Color
CIR
Pan
Bimat
Pos.
1-58,59, Color
60 CIR
Pan
No. of
Tanks
D
1
2
1
2
2
1
1
2
1
2
2
2
1
2
1
T
1
1
1
1
1
1
2
1
1
2
1
2
2
1
1
2
2
W
1
1
1
1
1
1
1
2
1
2
3
1
3
2
2
1
3
1
Leaks or
Seepage
D
1
2
1
2
0
1
1
3
1
2
3
3
3
0
0
T
1
2
1
2
1
1
2
1
1
2
1
2
2
2
1
3
2
W
1
2
1
2
3
1
2
3
1
2
2
1
3
2
2
2
3
2
Oil on
Water
D
E
E
1
0
0
1
2
0
1
1
0
3
E
E
E
T
E
E
1
2
1
2
0
1
2
0
2
3
0
0
E
E
E
W
E
E
1
2
3
1
3
3
1
3
3
1
3
3
2
E
E
E
Key: D = S. Daus; T = O.R. Temple; W = R.I. Welch
Table 3. Summary Results
24
-------
-M-Trash and Location
Actual Weather Condition * Debris of
Conditions of Dikes Present Effluents
Water Tracing
Condition Pipeline
Near Plants Routes
Clear
D
1
2
T W
1 1
2 1
D T
1 1
2 1
W
1
2
D
E
E
T
E
E
W
E
E
D
E
E
T W
E E
E E
D
1
1
T W
1 1
1 2
11 11
22 22
1 2
E E
E E
E E
1 1
2 1
0
1 1
2 2
1
Light Haze
1 1
2 1
2 2
1
2
2
1
2
2
1 1
1 2
2 2
1
3
0
1
2
3
1
2
3
1
2
0
1
2
3
1
2
3
1
1
2
1 1
1 2
2 2
1000' Over-
cast with
Light Rain
2
3
3
1 1
2 2
2 2
2 1
3 2
2 2
1
2
2
1 1
0 0
0 0
1
2
2
1
3
0
1
3
0
1
2
3
2
2
2
1 1
1 2
2 2
1200' Over-
cast with
Drizzle
2
2
3
1 2
2 3
2 2
2 1
3 2
2 2
2
3
2
E
E
E
E
E
E
E
E
E
2
3
0
2 1
3 3
3 3
1
1
2
1 1
2 2
2 2
312 312
E E E
332 222
5000' Over-
cast with
Light Rain
2
0
0
1 2
3 3
3 3
E E
E E
E E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E E
E E
E E
1
3
1
1 2
3 3
2 2
Table 3. Continued
25
-------
From the small sample in Table 3, it is fairly obvious that under
all weather conditions the color /1A combination was Superior. This
combination has excellent color contrast, grain characteristics, and sen-
sitivity. :
The color IR/12 was, at times, equal to the color film in inter-
pretability. Usually, however, it was inferior due to reduced exposure
1ati tude.
Although panchromatic photography occasionally exhibited good sharp-
ness and detail, it was definitely inferior to the color /1A due to the
absence of color contrast. In order to interpret this photography, it
was necessary to rely on subtle grey scale differences considerably
reducing the utility of the photography.
The following figures illustrate the general conclusion that color
/1A gives highly interpretable results regardless of the weather
conditions tested. Furthermore, no other film/filter type, of those
tested, provided more information than the color in any of the situations
evaluated. The figures show the entire sequence, whenever possible
of color, color infrared, and panchromatic photography. The imagery is
illustrative of the various weather conditions encountered, ranging from
clouds with 1,000 foot base and rain to clear, high visibility weather.
The latter conditions approximated those considered optimum, so that
the resulting photography could serve as a standard against which the
sub-optimum photography could be compared. As such it represents the
conditions exent at the time of acquisition of all photography dealt
with in Welch, et al. (1972). More specific comments will be made con-
cerning the relative advantages and disadvantages associated with inter-
preting each of the various categories of objects for each combination
of weather and film type in the following discussions of each figure.
Figures 4a, 4b, and 4care a sequence taken over the Avon, California
oil refinery under clear sky and high visibility (optimum) conditions
at about 1040 PDT on August 31, 1972. Figure 4a illustrates the
complex of oil storage and transportation facilities chosen for analysis
of detail under sub-optimum conditions. From such a high quality frame
as this, where all contrasts are interpretable, contrast examples illus-
trating criteria in Table 2 can be selected and used throughout the
entire testing procedure. Emphemeral features and characteristics such
as oil spills and leakage and condition of dikes are also interpretable.
Frequently, it was found necessary to use the higher quality color image
of a sequence first in order to establish the contrasts of the emphemeral
features present in a scene; then, the remainder of the images (color
infrared and panchromatic) were analyzed in sequence in relation to these
initial contrasts.
26
-------
FIGURE 4. TEST PHOTOGRAPHY
/7
-------
The frames in Figures 4d and 4e were exposed July 27, 1972, at 1206
PDT, and show an oil holding pond, oil separation facility and outfall
structure. Panchromatic coverage was not available for this sequence;
however, the color /1A and color 1R/12 are of excellent quality and
were acquired under optimum weather conditions. Ephemeral features such
as oil on water, effluents, and water quality are better illustrated on
this frame than on the Avon frame (Figure 4a). Interpreters again found
both frames to be of high quality, but found that the color yielded the
greatest and most easily extractable information. In this instance
relative image quality ratings were easier to establish than in the
previous figure, due to the slight overexposure of the color 1R/12.
This overexposure caused loss of detail in dikes, revettments, and oil
stains on the ground.
Figures 4f, 5a, and 5b show a ship salvage operation near Richmond,
California, and were obtained under a clear sky with medium haze at
0812 PDT on May 12, 1972. The interpreters considered this color frame
to be the most readily interpretable frame acquired and attributed this
to the slight under-exposure. Sharpness of this image is extremely high
and color contrast seems to be optimal. This excellent image yields a
wealth of information about very subtle conditions, such as the thin gos-
samer oil slick in the area of the ships and the bottom detail in the
near shore area. The higher contrast areas are also very easily inter-
preted.
This sequence is also an excellent example of the stepwise reduc-
tion of available information as one progresses from color to color in-
frared to panchromatic images. The color infrared frame shows a complete
loss of the subtle oil slicks which were so apparent on the color image.
Furthermore, due to the reduced blue and blue-green sensitivity, much
of the detail in the water is also lost. The reduced sensitivity also
affected the interpretability of subtle or low contrast oil spills and
seeps onto the ground. The blue tone of the older oil spills tends
to merge with the bluish soil background, and may also be confused with
other liquid spills or seeps which tend to have similar blue signatures.
Detail in the shadows is partially obscured on the color IR, as can be
seen by examining the ship shadows.
The panchromatic photograph demonstrates the drastic reduction
in readily available information due to the loss of color discrimina-
tion. The inadequacy of the black-and-white tonal representative is
exemplified by the oil spills and seeps on soil. Based on tonal dif-
ferences alone oil spills cannot be differentiated from areas of shadow,
only characteristic spill shapes allow identification. Older spills,
having lost their characteristic shape, become essentially undetectable.
Note also the loss of water quality information, and the complete loss
of detail in shadowed areas on the panchromatic photography.
28
-------
FIGURE 5. TEST PHOTOGRAPHY
29
-------
Figures 5c, 5d, and 5e of the Avon refinery area were obtained on
April 4, 1972, at 1407 PDT, under a 1,000 foot overcast and through a
light drizzle (corresponding to visibility reduction approximating
medium haze). The color imagery, although underexposed retains excel-
lent sharpness and good color contrast, even in the cloud shadow in the
upper right-hand quadrant. The companion color infrared frame is defi-
nitely inferior to the natural color image. Poor exposure latitude
has created a very dark image and greatly decreased color contrasts.
Reduction in image quality has resulted in loss of information about
low, and even medium, contrast objects. For example, ground oil
spills and seeps, very evident on the color frame, are not visible on
the color infrared frame. The trend continues with the panchromatic
imagery. Low light conditions have decreased tonal contrasts and have
produced a very "flat" image on which the low and medium contrast
features such as oil spills, dike erosion, trash and debris were
extremely difficult to identify.
Figures 5f, 6a, and 6b of the Richmond Naval Yard oil pond were
acquired at 1422 PDT, April 4, 1972, under overcast (1,000 feet cloud
base). The absence of shadowing due to the diffuse lighting, and the
excellent properties of the color emulsion combine to yield a highly
interpretable image. Notable is the reflection, not shadow, of the
cloud cover and of the photographic aircraft in the oil pool. This is
indicative of the flat and highly reflective surface of the oil and
leads to its positive identification. On the color frame, features of
all contrast levels are easily interpretable, allowing water quality
assessment. The color infrared frame has been optimally exposed, as
indicated by the color balance, yet the oil pond and oil spills are
rendered in the same blue tone as the oil-free tidal waters, roads and
roof tops. In the absence of comparative coverage, total reliance
would have to be placed on the reflective and surface characteristics
of the oil pond and, if the oil pond was not imaged at or very near the
principal point of the image, this technique would not generally be ap-
plicable. The same problem is apparent in panchromatic imagery, but
to an even greater degree.
Figures 6c, 6d, 6e, and 6f are examples of imagery obtained during
the rapid access exercise. This photography was obtained under 1,000 foot
overcast at 1004 PDT on June 22, 1972. The four examples in the sequence
show the color (SO-397), color infrared (2443), panchromatic (2402), and
the Bimat positive. The relative levels of interpretability for
these examples are basically the same as the previous examples.
The simulated rapid access photographic mission was performed
as described in the methods section. Weather conditions at overflight
time for the study areas were as follows:
30
-------
FIGURE 6. TEST PHOTOGRAPHY
31
-------
Area Sky Cover Visibility
Richmond oil pond Overcast at 1200; drizzle 3 miles
Richmond steel salvage Overcast at 1500' 5 miles
Avon Broken clouds at 2000' 15 miles
The same camera system was used for the rapid access test. The
film/filter combinations used were those used throughout the investi-
gation, with unfiltered Kodak 3400 Panatomic-X in the third camera.
the 2443 Aerochrome Infrared film was not processed by rapid access
but was acquired only to permit later comparison with film obtained
on other flights.
Timing (in minutes) of the initial film handling operations
was as follows:
Film Start Start First Look
Left Bimat Color at film
Aircraft Process Process at Airport
Panatomic-X 0 7 21
Aerial Color 0 5 60
Processing time included the application of a protective cover
sheet on the wet emulsion side of the positive Bimat, a common
practice for immediate viewing of Bimat processed film.
Relative levels of interpretability for the positive color
and negative panchromatic images are basically those expected from
identical exposures conventionally processed. The Bimat-processed
positive transparency is more readily interpretable than the
negative due to the "normal" assignment of grey levels and improved
contrast. No apparent image degradation has occurred in the image
transformation. The Bimat positive is a copy of the panchromatic
negative, but, as in this case, the information may be more easily
extracted due to the "normal" assignment of grey levels in a
positive image.
The preceding examples demonstrate that a tactical aerial
surveillance mission can be performed under sub-optimum weather
conditions and can be designed to produce both real-time and near
real-time data if careful flight planning and high quality photo-
32
-------
graphic systems and materials are used.
33
-------
SECTION VI
ACKNOWLEDGEMENTS
Earth Satellite Corporation wishes to acknowledge the support and
guidance provided by the EPA Project Officer, Mr. John Riley.
In addition to the authors, key EarthSat participants included
Dr. Robert N. Colwell, 0. Ray Temple, and Steven Daus.
34
-------
SECTION VII
REFERENCES
Welch, R. I., Marmelstein, A. D., and Maughan, P. M., "A Feasibility
Demonstration of An Aerial Surveillance Spill Prevention System,"
Final Report to the Office of Research and Monitoring,' Environmental
Protection Agency, 120 pp. (1972).
35
-------
APPENDIX 1
INTERPRETATION RESULTS
36
-------
Appendix la
Interpretation Results - Daus
37
-------
Film Sequence
Number Film Type
3-3,4,5,6
9-35,36,37
10-15, 16, 17
10-25,26,27
6-19,20,21
5-13,14,15
6-27,28,29
11-7,8,9
Color/lA
Cnlnr TR/1?
Pan/nf
Col or/1 A
Color IR/12
Color /I A
Color IR/12
Pan/nf
Color I/A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color IR/12
Pan/nf
Col or/1 A
O)
3 O>
en E
Oi-
CL+J
x
c
o aj
_i t/j
1
1
1
2
1
1
2
1
2
2
1
2
3
1
2
2
2
3
1
c
0 i.
a
t-
«-> 3
=- O
Q_ CfL
1
1
1
2
1
1
1
1
1
1
1
2
1
1
1
2
2
2
1
38
-------
Film Sequence
Number Film Type
11-22,23,24
11-16,17,18
11-31,32,33
12-1,2,3
12-14,15,16
12-28,29,30
12-36,37,38
-
12-47,48,49
12-7, 8, 9
12-22,23,24
Color IR/12
Color IR/12
Color /I A
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Color /I A
Color /I A
Pan/nf
Color /I A
Pan/nf
Color /I A
Pan/nf
Color /I A
Pan/nf
Color /I A
Pan/nf
Color /I A
tn c
O i-
Q.4->
X CO
LU Q£
G
G
G
G
G
G
G
G
Pu
Pu
G
G
Po
G
G
G
G
Pu
G
G
BULK
STORAGE
<*-
0 in
_*:
c
o
|~ r"
0 2
E
1
1
1
0
0
E
E
1
E
E
1
3
E
E
E
E
1
3
E
DIKES
c.
o en
t- j£
- -t-
-0 Q
C.
01-
C_> 0
2
1
2
1
2
3
1
2
2
1
3
1
3
1
0
1
3
2
2
1
oO .
tf)
-C-r-
y> $-
ra -Q
s- o>
f Q
2
1
1
1
2
2
F
E
2
2
2
1
3
E
E
1
3
2
2
1
REFINERIES
AND
PROCESSING
PLANTS
Location of
Effluents
E
E
E
E
E
E
p
E
E
E
E
E
E
E
E
E
E
E
E
E
Water
Condition
E
1
2
1
1
3
0
3
E
2
3
1
3
E
E
E
E
2
2
1
0)
£=
1 C/>
r G}
OJ -f->
G. 3
t- O
o_ cc
2
1
1
1
2
2
1
2
1
1
2
1
2
1
2
1
2
2
?
1
39
-------
Film Sequence
Number Film Type
4-33,34,35
4-7,8,9,10
4-44,45,46,47
9-28,29,30
10-6,7,8
4-70,71 ,72
4-64,65,66
3-10,11,12
Pan/nf
Color /I A
Color IR/12
Pah/nf
Color /I A
Color IR/12
Pan/nf
Color IR/12
Pan/nf
Color /I A
Color IR/12
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Color /I A
Color IR/12
Color /I A
Color IR/12
0)
3 O>
WJ C
O 1-
Q.4->
x «J
LU CC
G
G
G
G
G
G
G
G
G
G
Po
G
G
G
G
G
G
G
G
G
BULK
STORAGE
<»-
O «n
_^
. c
O 03
z:i
2
1
2
2
1
2
2
2
2
1
1
1
2
2
1
1
1
1
2
2
s_
o
3
1
2
2
2
3
3
0
2
1
1
1
2
3
1
1
1
2
1
1
c
0 S-
0)
-»->
«- ia
OS
E
E
E
E
E
E
E
E
E
1
1
E
E
E
1
1
1
1
1
2
DIKES
c
0 Vt
53
r -^
T3 O
E
0
Q. 3
-------
Film Sequence
Number Film Type
5-2,3,4,5
5-1 2,^5 if 6, 17
5-23,24,25,27
5-31 ,32,33
4-26,27,28
4-3,4,5
Pan/nf
Color /I A
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
O)
=J 0>
vt c
O i-
CL+J
x to
LLt C£.
G
Po
G
G
G
PC
G
G
G
G
G
G
G
G
G
PO
G
G
G
G
BULK
STORAGE
<*-
0 i/>
-^
« c
0 fC
z. \
2
2
2
2
2
E
1
1
1
1
1
1
2
2
1
1
1
1
1
1
s-
o
QJ O
_I
r- O)
-J-> -1£
-a Q
c:
o ^-
0 0
2
2
1
2
3
1
2
3
1
1
?
1
2
2
2
2
3
1
2
3
oS
(/)
co E
.TJ -Q
S_ G,
1 Q
2
2
2
2
2
1
1
2
]
1
1
1
2
2
1
1
2
2
2
2
REFINERIES
AND
PROCESSING
PLANTS
4-
0
to
C 4-1
O C
c QJ
j-> rs
c:
fO O
30
0
3
1
2
3
1
0
0
1
?
?
1
2
3
1
1
3
1
1
3
4->
Q. 3
r- O
C_ C£L
1
1
1
1
1
1
1
2
1
l
1
1
1
2
1
1
1
1
2
1
41
-------
Film Sequence
Number Film Type
4-19,20,21
4-42,43,44
6-2,3,4
6-27,28,29
2-23,24,25
2-33,34,35,36
2-29,30,31,32
2-40,41 ,42
Color /I A
Color IR/12
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color IR/12
Pan/nf
Color /I A
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
o>
S_
3 D>
(A G
O-t-
Q-+->
X 10
LU QC
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
BULK
STORAGE
4-
O l/>
-^
C
O IQ
z. i
2
2
1
2
2
2
2
2
2
2
1
2
1
1
2
1
2
1
1
2
Leaks or
Seepage
1
3
1
2
0
1
2
2
1
2
1
3
1
1
2
1
2
2
1
2
G
o s-
a)
r 4->
i «Q
OS
1
0
1
0
0
E
E
E
E
E
1
0
1
1
0
1
3
3
1
3
DIKES
c
0 l/>
r- CD
--> -i^
r -r
o o
sr
0 H-
O 0
1
2
1
2
2
1
2
2
2
2
2
3
1
3
3
1
3
2
1
2
oS
V)
-C T-
Wl S-
-------
Film Sequence
Number Film Type
2-56,57,58
2-47,48,49
2-3,4,5
8-21,22,23
8-33,34,35
7-13,14,15
7-6,7,8
7-70,71,72
7-23,24,25
Pan/nf
Color /I A
Color /I A
Pan/nf
Color /I A
Pan/nf
Color /I A
Color IR/12
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Pan/nf -
Col or/1 A
0)
3 O>
in c
O T-
0.4-i
X R3
LU C£
G
PC
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
BULK
STORAGE
i-
O V)
-^
c:
o to
z. \
2
1
2
2
1
2
2
2
1
1
1
1
1
2
1
2
2
1
2
2
s_
O O)
en
m CO
-^ Q.
ns a
CD CD
_J oo
3
1
1
3
1
3
1
2
1
1
2
1
2
3
1
2
3
1
2
1
c
0 S-
a>
i +->
i- re
0 12
3
1
1
0
1
0
1
0
1
1
3
1
0
0
1
1
0
E
E
E
DIKES
c
o in
r- (U
+J .*:
r »r
-O Q
G
0 H-
0 0
2
1
2
3
1
3
2
2
1
2
3
1
2
3
2
2
3
1
2
1
c* -
in
-C i-
01 S-
(O XI
S_ 0
f Q
2
1
2
2
1
3
2
2
1
2
3
1
2
2
2
3
2
1
2
1
REFINERIES
AND
PROCESSING
PLANTS
Location of
Effluents
0
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
Water
Condition
0
1
1
0
1
3
1
2
1
2
3
E
E
E
2
3
0
1
0
E
«-» 3
-i- O
0_ C£
1
1
2
2
1
2
2
1
1
1
1
1
2
2
1
1
2
1
2
2
43
-------
Film Sequence
Number Film Type
7-75,76,77
7-86,87,88
7-94,95,96
8-10,11,12
Color IR/12
Pan/nf
Color /I A
Pan/nf
Pan/nf
Color /I A
0)
ZJ O>
in G
O -r-
Q.4->
X
r- IQ
OS
E
E
1
2
E
E
DIKES
c
o ^:
r »r
O Q
C
0
r
-------
Appendix Ib
Interpretation Results - Temple
45
-------
Film Sequence
Number Film Type
1-35,36
1-22,23,24
1-5,6,7
5-31,32,33
10-7,8,9
4-53,54,55
1-58,59,60
9-9,10,11
1-58,59,60
1-27,28,29
3-18,19,20
5-2,3,4
12-1,2,3
11-22,23,24
4-25,26,27
7-6,7,8
4-7,8,9,10
4-3,4,5
12-36,37,38
11-7,8,9
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
O)
3 en
V) C
Oi-
Q--l->
X «0
I_U CC
G
PC
G
G
PC
PC
PC
Po
G
G
PC
G
PC
G
PC
Pu
PC
PC
G
PC
BULK
STORAGE
M-
O
-S£
C
O to
E
1
1
1
1
E
1
E
1
E
E
1
E
E
E
E
1
E
1
1
i.
O OJ
01
«O
^£ Q.
0 C
-i- ^
CO
0 H-
O «*-
I UJ
E
E
E
E
E
E
E
E
E
1
E
E
E
E
1
E
E
E
E
E
Water
Condition
1
E
E
E
E
3
E
E
E
1
2
E
E
E
2
E
E
E
E
E
QJ
C
I W
i O
a -»->
a. 3
t- O
a- en
1
2
2
1
1
1
2
1
1
E
E
1
2
1
1
1
2
1
1
1
46
-------
Film Sequence
Number Film Type
4-18,19,20
10-6,7,8
5-30,31,32
2-56,57,58
8-18,19,20
1-18,19,20
1-5,6,7
11-31,32,33
6-13,14,15,16
1-44,45,46
12-7,8,9
1-51,52,53
1-73,74
5-14,15,16
10-17,18,19
5-13,14,15,16,1]
1-67,68,69
1-18,19,20'
B-21,22,23
M3,14,15
Pan/nf
Color /I A
Color IR/12
Color /I A
Color IR/12
Color /I A
Color /I A
Color /I A
Color /I A
Color /I A
Color /I A
Color /I A
Color /I A
Color IR/12
Pan/nf
Color / 1A
tolor IR/12
>an/nf
Color /I A
Dolor IR/12
2
3 en
in c
O-r-
Q.-l->
X 10
LU o:
PC
G
G
G
G
G
G
G
G
G
PC
PC
G
PC
PC
PC
G
G
G
G
BULK
STORAGE
t-
O en
.^
E
O (G
E
1
1
1
E
1
1
1
E
E
E
1
E
E
E
E
E
1
E
E
°S
(A
5£
E
E
E
E
1
E
2
E
1
1
2
E
1
2
3
1
1
E
E
1
DIKES
Condition
of Dikes
2
1
1
1
2
1
1
1
1
1
1
2
1
1
1
1
1
2
1
1
08
«/»
-Ef-
l/> -S-
01 -M
Q. 3
T- O
O. CC
E
1
1
1
1
2
2
1
1
1
2
2
E
E
E
E
1
2
E
E
47
-------
Film Sequence
Number Film Type
7-157,158,159
4-74,75,76
7-6,7,8
7-148,149,150
7-13,14,15
11-7,8,9
8-27,28,29
1-5,6,7
7-94,95,96
10-15.16.17
9-12,13,14
7-141,142,143
7-75,76,77
11-16,17,18
1-68,69,70
4-70,71,72
8-6,7,8
2-2,3,4
4-33,34,35
2-37c,d,e
Pan/nf
Color /1A
Color IP/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color IR/12
Pan/nf
Color IR/12
Pan/nf
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
(U
=j cn
10 E
O -i-
O_4->
X as
uj o:
G
G
PC
G
G
G
PC
PC
G
PC
PC
PC
G
Po
PC
PC
PC
G
G
G
BULK
STORAGE
*f-
O c/>
^t
E
O CO
2:1
1
E
E
E
E
1
E
1
E
E
E
E
E
E
E
E
E
1
1
E
&.
o
1
1
1
1
1
1
1
1
1
1
1
2
1
2
2
1
1
2
1
2
0 i.
o>
I -t-i
r- (O
0 3
E
1
2
3
1
E
1
E
2
2
2
0
1
3
3
1
3
E
E
2
DIKES
E
O V)
r- E
(3 0
3 C_J
E
1
E
3
E
E
E
2
E
E
E
F
E
2
3
1
3
F
E
E
o
E
r- CO
r 0)
CU +->
Q. ZJ
r- O
Q. CCL
1
E
1
E
E
1
1
2
E
1
1
2
1
E
p
1
E
?
1
2
48
-------
Film Sequence
Number Film Type
1-44,45,46
2-66,67,68
4-57,58,59
1-35,36,37
3-18,19,20
1-35,36,37
6-26,27,28,29
3-10,11,12
1-44,45,46
1-27,28,29
9-28,29,30
4-64,65,66
10-23,24,25
8-33,34,35
3-3,4,5
9-20,21,22
7-23,24,25
3-25,26,27
4-8,9,10
10-25,26,27
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /I A
o>
3 0>
«/> C
O -i-
0.4->
x ia
LLJ C£
PC
G
G
PC
PC
PC
G
G
PC
PC
G
G
G
G
G
PC
G
Po
PC
G
BULK
STORAGE
M-
0 00
^L
C
0 (C
E
1
E
E
E
E
1
E
E
E
E
E
E
E
E
1
1
1
1
E
s-
o a
in n:
-*: a.
aj a
_I
3
1
2
3
1
2
2
1
2
2
1
1
1
1
1
1
1
1
2
1
c
0 S-
OJ
i 4J
r- tO
o :s
0
E
2
0
1
2
E
1
3
2
1
1
1
1
E
E
E
E
E
1
DIKES
c
0 00
r- J^
-5 o
c
0 M-
0 0
3
1
1
3
1
2
2
1
2
2
1
1
1
1
1
1
1
1
1
1
oa
-c: -i-
00 S-
(0 jQ
S- 0)
f 0
E
E
1
E
1
E
E
1
E
2
E
E
E
E
E
E
E
E
E
1
REFINERIES
AND
PROCESSING
PLANTS
Location of
Effluents
3
E
2
E
E
E
E
E
E
2
E
1
E
E
E
E
E
E
E
E
c.
o
r
4->
i- -r-
OJ T3
4-J C
r3 O
"3. CJ
3
E
2
3
1
2
E
1
3
3
1
E
E
1
E
E
E
E
E
E
a;
c
r- W
r OJ
O +>
d. 13
r- O
a. a:
2
1
E
2
E
2
2
E
2
E
1
1
1
1
1
1
1
1
2
E
49
-------
Film Sequence
Number Film Type
1-51,52,53
2-30,31,32
6-19,20,21
1-18,19,20
1-18,19,20
10-15,16,17
1-27,28,29
2-22,23,24,25
12-14,15,16
6-26,27,28,29
12-22,23,24
4-44,45,46,47
2-44,45,46
12-28,29,30
9-2,3,4
11-2,3,4
4-7,8,9,10
3-10,11,12
10-7,8,9
2-29,30,31,32
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
CU
=j en
t/> G
O -i-
Q.+J
x to
LU Q;
PC
G
G
PC
PC
G
PC
G
PC
G
G
PC
G
Po
G
G
G
G
G
G
BULK
STORAGE
i«-
o to
^4
C
o to
3
E
E
1
1
E
E
E
E
1
E
1
E
E
E
1
1
E
1
E
i.
0 O)
en
to to
^ 0.
(O CU
CU CU
_i c/>
0
1
1
1
2
1
2
3
1
1
1
1
2
1
1
1
1
1
1
1
0 L.
cu
r »->
r- fO
0 3
E
1
1
E
E
1
1
0
1
E
1
E
2
1
1
E
E
1
E
1
DIKES
c
o to
r- CU
4-> ^
r" «i
-a o
G
OM-
0 0
0
1
1
2
1
1
2
2
1
2
1
1
1
1
2
1
1
1
1
1
o3
in
-E: «-
to i.
to -a
s- cu
1 Q
E
1
1
E
E
E
2
E
1
E
1
E
1
E
2
E
E
1
E
1
REFINERIES
AND
PROCESSING
PLANTS
Location of
Effluents
E
E
E
E
E
E
2
E
E
E
E
E
E
E
E
E
E
E
E
E
c
o
fj
S_ -i-
QJ TD
-!-> C
(3 O
"S. C_>
E
F
E
E
E
E
2
E
0
E
E
E
2
E
E
E
E
1
E
1
cu
c
r- tO
r CU
CU »->
CL n
i- O
0. Cg
3
F
F
2
1
1
E
E
E
1
E
2
1
E
1
1
E
1
E
50
-------
Film Sequence
Number Film Type
27
5-23,24,25,26,
7-78,77,79
5-2,3,4,5
6-19,20,21
5-31,32,33
12-47,48,49
6-13,14,15
2-38,39,40
2-76,77,78,79
5-2,3,4
7-86,87,88
3-3,4,5,6
2-32,33,34
4-62,63,64
4-42,43,44
2-38,39,40
6-19,20,21.
4-26,27,28
2-51,52,53
6-13,14,15
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color JR/12
Pan/nf
0>
3 D>
V) C
O <-
Q-+->
X nj
UJ C£.
G
PC
>G
PC
G
Pu
PC
G
G
G
PC
G
PC
PC
PC
Po
G
G
G
G
BULK
STORAGE
n-
O in
.*:
« c
O (0
Zh-
E
E
1
E
1
1
E
E
E
1
E
E
E
2
E
E
E
E
1
E
i.
o a
1/5 (Z
-* a.
i 4-i
i ju:
i 'r-
-o a
c
O S-
C_J O
1
2
1
2
2
1
2
2
1
2
2
1
2
2
1
2
2
1
2
2
o3
in
.C 'I
in S-
(X5 .0
S- O)
1 Q
E
1
E
1
E
E
E
E
E
E
E
E
2
E
1
E
2
E
E
E
REFINERIES
AND
PROCESSING
PLANTS
«4-
O
C
ra O
"3. tj
E
E
E
E
E
E
2
E
E
E
E
E
3
E
1
E
E
1
E
3
0)
c
r- CO
i
o. rs
i- 0
D- C£
1
E
1
E
1
1
2
1
1
1
2
1
E
2
E
2
E
1
2
2
51
-------
Film Sequence
Number Film Type
27
5-23,24,25,26,
10-25,26,27
5-15,16,17
4-83,85
35
4-32-32,33,34,
3-10,11,12
8-10,11,12
7-70,71,72
3-3,4,5
4-3,4,5
6-2,3,4
10-2,3,4
6-2,3,4
4-3,4,5
6-1,2,3
4-19,20,21
4-42,43,44
2-47,48,49
1-58,59,60
Color /1A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /I A
Color IR/12
Pan/nf
Color /1A
Color IR/12
cu
3 0>
10 G
O !-
Q.-M
X fC
LU C£
G
G
PC
PC
G
G
G
G
G
G
G
G
G
G
G
G
G
PC
G
PC
BULK
STORAGE
M-
O i/>
j*:
c:
O CO
E
E
E
E
1
E
1
E
E
E
1
1
1
E
1
E
E
1
1
2
i.
O O)
01
to rct
-i£ Q.
(3 CD
QJ O)
_1 00
1
2
2
1
1
E
1
1
1
1
1
1
1
1
1
1
1
1
1
3
c
O i-
c- c«
0 3
1
3
3
1
E
1
E
1
1
1
E
E
E
1
E
1
1
E
E
E
>
DIKES
Condition
of Dikes
1
1
2
1
1
2
1
1
2
1
1
E
1
1
E
E
E
2
1
3
o3
to
-C !-
l/> S_
tO -Q
i. QJ
\ Q
E
1
2
E
E
1
1
1
1
1
E
E
E
E -
E
1
1
E
E
E
REFINERIES
AND
PROCESSING
PLANTS
Location of
Effluents
E
E
3
1
E
E
E
E
E
1
E
E
E
E
E
1
1
E
E
E
c
o
r"
4J
i. <-
OJ -o
+J C.
ta o
3 0
E
3
3
1
E
2
E
E
E
1
E
E
E
1
E
1
1
E
E
E
QJ
C
r- tO
c CD
CO 4->
Q. ZS
r- O
Q. C£
1
E
E
1
2
E
1
E
1
2
1
1
1
1
1
E
E
2
2
3
52
-------
Film Sequence
Number Film Type
5-24,25,26
2-23,24,25
2-44,45
4-32,33,34
2-33,34,35,36
4-26,27,28
2-51,52,53
22 Sep 72 A
22 Sep 72 A
22 Sep 72 C
22 Sep 72 C
22 Sep 72 B
22 Sep 72 B
25 Jul 72 C
25 Jul 72 A
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Bimat pos
Bimat pos
Bimat pos
Bimat pos
Bimat pos
Bimat pos
Pan/nf
Pan/nf
OJ
3 cn
V) C
O T-
Q.4->
X (O
LU o;
G
G
Po
V
PC
G
G
PC
G
G
G
G
G
G
G
G
BULK
STORAGE
t-
0 01
-ini
C
0 ro
Z f
E
E
E
1
E
E
1
1
1
E
E
E
E
E
1
£-
o a
to re
.*: a.
rd QJ
a> a;
_i to
1
1
2
1
1
1
2
1
1
1
1
2
1
2
1
C
0 i-
OJ
1 )->
r- ro
0 ^
1
1
1
E
1
1
E
E
E
2
2
2
3
0
E
DIKES
C
0 V)
1- -i c
ro O
"3. O
F
E
?
E
E
2
E
E
E
2
2
E
E
E
E
0)
C
I CO
i QJ
a; +J
a. rs
i- O
CL. C£
1
1
E
1
1
1
2
2
1
E
E
2
1
E
1
53
-------
Appendix Ic
Photointerpretation Results - Welch
§4
-------
Film Sequence
Number Film Type
10-6,7,8
10-7,8,9
9-2-, 21, 22
9-28,29,30
9-9,10,11
4-42,43,44
4-57,58,59
4-18,19,20
1-58,59,60
1-58,59,60
1-58,59,60
1-44,45,46
1-44,45,46
1-44,45,46
7-6,7,-8
7-6,7,3
7-141,142,143
7-86,87,88
Color /I A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Color /1A
Color IR/12
Pan/nf
Color /1-A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Color /1A
Color IR/12
Pan/nf
Bimat
at
3 0>
l/> E
O-i-
Q.-P
X tO
UHCC
G
G
G
G
G
G
G
G
G
Pu
G
G
G
G
G
Pu
G
G
BULK
STORAGE
4-
O c/>
^£
E
0 fO
1
1
1
1
1
1
1
2
1
3
1
1
2
3
1
3
2
2
A-
0 0)
CT
to fC
.M Q.
_I I/O
1
2
3
1
2
1
2
3
2
3
2
1
2
2
1
3
2
2
E
0 i-
i- ro
o :2
E
E
E
1
2
1
3
3
1
2
2
1
3
3
1
3
3
2
DIKES
E
O to
r- ^i
I !
T3 Q
C
O 4-
<_> o
1
1
1
1
2
1
2
2
2
3
3
1
2
2
2
3
2
2
oS
to
-C '!-
to s~
cs J3
S- 0!
t Q
1
2
2
1
2
1
2
2
2
3
2
1
2
2
2
3
2
2
REFINERIES
AND
PROCESSING
PLANTS
Location of
Effluents
E
E
E
E
E
1
2
3
1
2
2
1
2
2
1
2
2
1
d
o
4->
S- -r-
QJ -0
4-> E
ra O
3 0
0
0
0
1
1
1
2
3
1
2
2
1
2
3
1
3
3
2
Q- 13
r- O
Q. C£
1
2
1
1
2
1
2
2
2
3
2
1
2
2
1
2
2
2
55
-------
SELECTED WA TER * Report NO.
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
3. Accession No.
w
4- Title 5, Report Date
Aerial Spill Prevention Surveillance e.
During Sub-Optimim Weather 8_ Performing Organization
7. Author(s) Report No.
Welch, R.I., Marinelstein, A.D., Maughan, P.M.
9. Organization
Earth Satellite Corporation
1747 Pennsylvania Avenue, N.W.
10. Project No.
68-01-0191
Washington, D.C. 20006 " Type of Report and
3 Period Covered
12. Sponsoring Organization
15. Supplementary Notes
Environmental Protection Agency report number,
EPA-R2-73-243, September 1973.
16. Abstract
Multi-band aerial photography was acquired during specified conditions of
cloud cover and reduced visibility considered to be representative of a
nearly infinite range of sub-optimum weather conditions. (For aerial photo-
graphy, optimum is defined as clear skies and greater than 15 miles visibility.)
Basic techniques were derived from an earlier study designed to yield strategic
spill prevention surveillance. (Welch, et al. 1972)
Results indicated that only one film tested, a high sensitivity color
positive film, provided consistently interpretable results. Rapid
access techniques were also evaluated leading to recommendations for
a tactical system providing a capability for both real-time and near
real-time system update during sub-optimum aerial photographic conditions.
17a. Descriptors
Water pollution sources, oil, chemicals, remote sensing, aerial photography
17b. Identifiers
*Aerial photography, *sub-optimum weather, hazardous materials
17c. COWRR Field & Group
18. Availability 19. Security Class.
(Report)
20. Security Class.
(Page)
21. No. of Send To:
Pages
PrffP WATER RESOURCES SCIENTIFIC INFORMATION CENTER
rr"-e U.S. [DEPARTMENT OF THE INTERIOR
WASHINGTON. D. C. 20240
\\ Abstractor /\n an p< Marniel stein [institutionEarth Satellite Corporation
W(RSIC 102 (REV. JUNE 197l) -ftU.S. GOVERNMENT PRINTING OFFICE : }9*4 O-527-765
------- |