PB84-177898
Surface Treatment Agents for
Protection of Shorelines from Oil Spills
Woodward-Clyde Consultants, San Francisco, CA
Prepared for
Municipal.Environmental Research Lab.
Cincinnati, OH
Apr 8<2
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FE84-177898
EPA-600/2-84-085
April 1984
SURFACE TREATMENT AGENTS FOR PROTECTION
OF SHORELINES FROM OIL SPILLS
by
Carl R, Foget, Robert M. Castle, Susan Nsughton, James 0. Sartor
Woodward-Clyde Consultants
Sen Francisco, California 94111
Michael Miller, Philip Dibner
URS Research Company
San Mateov California 94402
Donald E. Glowe, Frederick Heber, B.J. Yager, P.E. Cassidy
Texas Research Institute, Inc.
Austin, Texas 78767
Grant No. R804639
Project Officer
Leo T. McCarthy, Jr.
Oil and Hazardous Materials Spills Branch
Solid and Hazardous Waste Research Division
Municipal Environmental Research Laboratory-Cincinnati
Edison, Hew Jersey 08837
MUNICIPAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE CF RESEARCH Af.'O DEVELOPKtNT
U.S. EKVIRO^ISHTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
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TECHNICAL REPORT DATA
(Pbcst read Imuuctiotu on lilt rei-erw btfort c
1. REPORT NO.
2.
3. RECIPIENT'S ACCEf.Sl
A. TITLE AND StjOTITLE
SURFACE TREATMENT AGENTS FOR PROTECTION OF
SHORELINES FfOM OIL SPILLS
5. REPORT DATE
6. PERFORMING ORGANIZATION CODE
ENT'S ACCESSION. MC,,
4 17?89 fa
April
7. AUTHORS)
Carl R. Fogot, et al.
8. PERFORMING ORGANIZATION REPORT NO.
<>. PERFORMING ORGANIZATION NAME AND ADDRESS
Woodward-Clyde Consultants
Three Embarcadero Center, Suite 700
San Francisco, California 94111
10. f ROURAM ELEMENT NO.
CBKD1A
11. CONTRACT/GRANT NO.
R804639
12, SPONSORING AGENCY NAME AND ADDRESS
Municipal Environmental Research Laboratory— Cin., OH
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
13. TYPE OF REPORT AND PERIOD COVERED
Final Report, 1975-1979
14. SPONSORING AGENCY CODE
EPA/600/14
IS. SUPPLEMENTARY NOTES
Project Officer: Leo T. Me Carthy (201-321-6630)
io. ABSTRACT A literature review and laboratory tests were conducted to provide a basis
for analyzing the results of previous tests on surface treatment agents, compare agent
effectiveness, and recommend agents for preliminary field tests. The surface treatment
agents evaluated during the preliminary tests were film-forming agents, dispersing
agents, anc? a surface collecting agent. From the results of these tests, two film-
forming agents, polyvinyl acetate and xanthan gum, a surface collecting agent, and a
flowing film of water were recommended and tested during full-scale field tests at
Sewaren Beach, New Jersey. The results of the full-scale field tests showed that
polyvinyl acetate provided both beach And marsh test plots with the most effective
long-term protection. The toxic effects of the various agents on the Eastern Blue Crab
and cord grass (Spartina foliosa) were also evaluated. .-• .
This report was submitted in fulfillment of Grant No. R804639 awarded to the American
Petroleum Institute under the sponsorship of the U.S. Environmental Protection Agency.
The API awarded a contract to Woodward-Clyde Consultants, who, with their subcon-
tractors, Texas Research Institute, Inc., and URS Research Company, completed the
research in 1979. This report covers the period 1975-1979.
17.
DESCRIPTORS
K6Y WORDS ANO DOCUMENT ANALYSIS
~fb.lD£NTIFIEfiS/OFEN ENDED TERMS
c. COSATI Fw'd/Group
Water Pollution
Shore Protection
Polyvinyl Acetate
Xanthanates
Water
Dispersants
18. OISTKtUUTlON STATEMENT
Release to public
Oil Spill Cleanup, Film-
forming Agents, Surface
Collecting Agents
13/02
11/09
11/07
07/03
11/11
19. J.ECUKIVY CLASS in
Unclassified
21. no. OF PASC
20. ££CUKITY CLASS ITTlilpc^e 1
Unclassified
22. 1'HICE
£PA
20-1 (R»». <-77) PREVIOUS EDITION is csioucre
1
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DISCLAIMER
The information in this document has been funded wholly or in part by the
United States Environmental Protection Agency under Grant No. R804639 to
Woodward-Clyde Consultants. It has been subject to the Agency1 s peer and
administrative review, and it has been approved for publication as an EPA
document. Mention of trade names or commercial products does not constitute
an endorsement or recommendation for use.
ii
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FOREWORD
The U.S. Environmental Protection Agency was created because of
increasing public and government concern about the dangers of: pollution to
the health and welfare of the American people. Noxious air, foul water, and
spoiled land are tragic testimonies to the deterioration of our natural
environment. The complexity of that environment and the interplay of its
components require a concentrated and integrated attack on the problem.
Research and development is that necessary first step in problem
solution; it involves defining the problem, measuring its impact, and
searching for solutions. The Municipal Environmental Research Laboratory
develops new and improved technology and systems to prevent, treat, and manage
wastewater and solid and hazardous waste pollutant discharges from municipal
and community sources, to preserve and treat public driaking water supplies,
and to minimize the adverse economic, social, health, and aesthetic effects
of pollution. This publication is one of the products of that research and
provides a most vital communications link between the researcher and the user
community.
This report describes the laboratory and field research that evaluated
products and techniques for the protection and restoration of shorelines form
oil spills. THe report will be of interest to those involved in oil spill
prevention, control, and ccuntemeasures.
Francis T. Mayo,
Director
Municipal Environmental Research Laboratory
iii
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ABSTRACT
Surface treatment agents for protecting shorelines from spills were
evaluated by means of a literati re review, laboratory tests, and field tests.
Results of the literature review and laboratory tests were used as the basis
for (1) analyzing the results of earlier tests on surface treatment agents for
oil spills, (2) comparing effectiveness of surface treatment agents, and (3)
recommending agents for preliminary field tests. Preliminary field tests of
agent effectiveness, toxicity, and application techniqes were undertaken on
slat-marsh sections and simulated beaches. The surface treatment agents tested
during the preliminary field tests were film-forming agents (polyvinyl acetate,
xanthum gum) and the surface collecting agents were recommended for and tested
during the full-scale field tests at Sewaren Beach, New Jersey. In addition, a
flowing film of water was tested for effectiveness as a surface treatment agent.
The results of the full-scale field tests showed that polyvinyl acetate
provided both beach and marsh test plots with the most effective protection
against the test oils (16 fuel oil, #2 fuel oil, and Arabian crude oil) because
it substantially decreased oil penetration, and it allowed surface oil to be
easily removed by flus/iing. Xanthan gum was the least efective on the beach
test plots of the three film-forming agents, but it did provide sane beach
substrate protection. On the marsh test plots, xanthan gum appeared to be the
most effective short-term agent for protecting the vegetation and substrate
from contamination by Arabian crude oil, but it was removed by flushing. The
flowing film of water provided the best protection against beach surface con-
tamination by oil, but it tended to erode channels in sand beaches, causing
uneven coverage and allowing some oil penetration. The flowing film of water
was not effective as a surface treatment agent for salt marshes because it
could not provide a uniform film over the substrate and vegetation. The surface
collecting agent was effective in confining oil under nonturbulent conditions.
Turbulent conditions (caused by breaking waves impinging on the test area)
caused the confined oil slick to break up.
Results of several studies are included as appendices to this report.
They are: Prelimnary Agent evaluation Tests; Dioassay of Eastern Blue Crab with
Surface Treatment Agents; Siedler Beach Surface Treatment Agents Tests; and
Laboratory Investigation of Improved Materials for Shoreline Protection from
Oil Spills.
This report was submitted in fulfillment of Grant No. R804639 by the
American petroleum Institute under the sponscrhsip of the U.S. Environmental
Protection Agency. The API awarded a contract to Woodward-Clyde Consultants,
who, with their subcontractors, Texas Research institute, Inc., and UR3 Research
Conpany, ccwpieted the research. The report covers the period July, 1975 to
July, 1979, and work was completed by October, 1979.
iv
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CONTENTS
Foreword iii
Abstract iv
Figures vi
Tables vi
Acknowledgments. . . vii
1. Introduction 1
Scope 1
Report Organization 2
2. Conclusions 3
Beaches 3
Salt Marshes 5
3. Recoimendations 7
4. Full-Scale Field Tests 8
Test Site 8
Test Oils 8
Agent Evaluation Procedures ...." IjJ
Data Collection . 11
Agent Application Equipment 11
Test Results 15
Discussion 20
SiEttnary 30
Appendices '.
A. Literature Review 32
B. Preliminary Agent Evaluation Tests 43
C. Bioassay of Eastern Blue Crab With Selected
Surface Treatment Agents 96
D. Surface Treatment Agent Tests - Siedler Beach,
Jersey, October 18 and 21, 1978 108
D-l. SecLbranr Sanpling Procedures 122
D-2. Laboratory Investigation of Itproved Materials
for Shoreline Protection from Oil Spills 124
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FIGURES
Nuntoer Page
1 location of test site 9
2 Location of test plots in four test zones 14
TABLES
Num&er Page
1 Surface Treatment Agents Evaluated During Program 2
2 Ranking of Film-Forming Agents Evaluated During Test Program. . 4
3 Characteristics of Test Oils 10
4 Environmsntal Conditions 13
5 Surface Treatment Agent Beach Field Test: 16 Fuel Oil 16
6 Surface Treatment Agent Baach Field Test: #2 Fuel Oil 17
7 Surface Treatment Agent teach Field Test: Arabian Crude Oil . . 18
8 Beach Surface Treatment Agent Conparison 19
9 Surface Treatment Agent Marsh Field Test: #6 Fuel Oil 24
10 Surface Treatment Agent Marsh Field Test: Arabian Crude Oil . . 25
11 Surface Treatment Agent Marsh Field Test: #2 Fuel Oil 26
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ACKNOWLEDGEMENTS
Acknowledgement is gratefully given for the cooperation and assistance
provided by the following persons: Mr. Eugene Destefano, Director of Fublic
Works, Woodbridge, New Jersey, for arranging logistic support for the test
program; Mr. Karl Birns, Director of Special Services, New Jersey Department of
Environmental Protection, for permission to use the Sewaren Peach test site;
the Alameda County (California) Flood Control District, for permission to use
the preliminary field test site at Coyote Hills Slough in Fremont, California;
the Clean Harbor Cooperative of New York City, Mr. M.C. Zwirbla, Manager, and
member companies Gulf Oil, Hess Oil, and Chevron USA, for providing booms for
the Sewaren Beach test site; Mr. Maurice Sproul, Mr. Victor Manolio, and Mr.
David Mercer, of the Mason and Hanger Company, for providing logistic support
and assorted equipment and for their active participation in the full-scale
field test program; and Chevron USA for providing the test oils used in both
the preliminary and full-scale field tests.
The authors also gratefully acknowledge the support and guidance given by
members of the American Petroleum Institute's shoreline, subcommittee, Mr. F.M.
Smith (Chevron USA), Chairman; Mr. D. E. Fitzgerald (Atlantic Richfield Com-
pany); Mr. F.T. Jones (CITGO); Mr. G.P. Mulligan (Shell); Hr. J.S. Dorrler
(EPA); and Hr. W.L. Lewis (Exxon USA), Chairman of the Oil Pollution Prevention
and Control Committee; by Mr. Thomas Kanney, who served as contract officer for
the American Petroleum Institute; and hy Mr. Leo McCarthy, who served as
Project Officer for the Environmental Protection Agency.
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SECTION 1
INTRODUCTION
The state of tne art for cleanup of oil-contaminated shorelines is well
developed only for sandy beaches; cleanup of other oil-contaminated shoreline
types requires extensive use of manual labor. The procedures for protecting
shorelines from oil contamination are even less well developed and usually
consist of deploying bourns to direct oil away from a specific area. Wind,
current, and surf action can, however, severely limit boom performance,
allowing oil to escape and causing subsequent contamination of a shoreline.
In 1974, the American Petroleum Institute and the U.S. Envirorsrental
Protection Agency funded four laboratory projects to obtain information on
materials that might be useful in protecting beaches and salt marshes from
oil contamination. The results of these studies (1) identified eight natural
and synthetio materials that, if applied to a beach or salt marsh, might
offer the shoreline protection from oil contamination, and (2) recormended
that the candidate agents that were identified be tested in the field under
full-scale conditions.
The American Petroleum Institute obtained a research grant from the En
vironmental Protection Agency to continue this effort and awarded a contract
to Woodward-Clyde Consultants and their subcontractors, Texas Research Insti-
tute, Inc., and URS Research Coerpany. The purpose of the project was to
evaluate, under field conditions, the effectiveness of the selected surface
treatment agents in protecting beaches and salt marshes from oil spills and
in assisting in the cleanup of shorelines previously contaminated by oil
spill. Toxicity screening tests on cordgrass (Spartina foliosa) are dis-
cussed in Appendix B and c.i Eastern Blue Crab (Callinectus sapidus in
Appendix C.
The scope of this project involved the following:
* Correlating data on the eight agents recorsmanded by previous studies
into a ccsraror, baseline through literature reviews and laboratory
testing.
* Conducting preliminary field tests with the agents and three types
of oil (S2 fuel oil, Arabian crude oil, and £6 fuel oil) on marsh-
grass plots and siitralated beaches to determine the most effective
agents for full-scale field testing.
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* Conducting full-scale field tests by applying the agents to actual
beach and salt-marsh areas and contaminating the areas with three
types of oil (#2 fuel oil, Arabian crude oil, and #6 fuel oil)
* Conducting preliminary toxicity tests of selected agents.
The surface treatment agents that were tested during the project are
shown in Table 1.
REPORT ORGANIZATION
The remainder of this report presents specific details and information
on the performance of the project. Section 2 presents conclusions of the
full-scale field tests, and Section 3 states recommendations for agent use
and additional research. Section 4 presents the results of the full-scale
field test program at Sewaren, New Jersey. Specific data from the litera-
ture review, laboratory tests, and preliminary field tests are given in
Appendices A and B. Appendix C gives the results of the eastern blue crab
bioassay. Appendix D gives the results of the evaluation of surface treat-
ment agents.
TABLF. 1. SURFACE TREATMENT1 AGKNTS EVALUATED DURING PROGRAM
Preliminary Full-Scale
Field Tests Field Tests
Agents Laboratory Alameda Sewaren
Sodium silicate x x
Sodium borate/sodium silicate
mixture x x
Citrus pectic x x
Xanthan gum x x x
Polyvinyl acetate x x x
Flowing f.ilm of water x x
Surface collecting agent (Oil Herder) x y x
Dispersant A (Correxit 7664) x x
Dispersant B (BP 1100-X) x
Dispersant C (BP 1100 KD) x
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SECTION 2
CONCLUSIONS
The full-scale field tests of surface treatment agents were undertaken as
two tasl
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TABLE 2. RANKING* OP FILM-FORMING AGENTS EVALUATED DURING TEST PROGRAM
Film-Forminq Aqent Ranking
Agent
Polyvinyl acetate
Xanthan gum
Flowing water
Sand Beach
Oil Type
No. 6 No. 2 Arabian No.
Fuel Oil Fuel Oil Crude Oil Fuel
Short
Term
111 2
333 1
2 22 3
Marsh . . .-
Oil Type
6
Oil
Long
Term
1
2
3
No.
Fuel
Short
Term
1
2
3
2
Oil-
Long
Term
1
3
2
Arabian
Crude
Short
Term
2
1
3
Oil
Long
Term
1
2
3
* Agents are ranked in order of effectiveness in each test.
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SALT MARSHES
1. Two of the ^urface treatment agents tested, polyvinyl acetate and
xanthan gun, have definite potential for application in protecting
salt marshes from oil contonination.
2. Polyvinyl acetate was particularly effective in protecting the salt
marsh from contamination by £2 fuel oil and Arabian crude oil.
Flushing of the oil frcta contaminated vegetation and riarsh substrate
was easier for PVA than with other agents or the control.
3. Xanthan gun appeared to be a slightly more effective short-term
(i.e., hours) agent for protecting the nvjrsh vegetation and substrate
from contamination by Arabian crude oil. After a single flushing,
however, the agent was largely removed fron both plants and
substrate.
4. The effectiveness of the continuous film of flowing water in marshes
was limited. It was difficult to attain a uniform water flow that
would protect both the vegetation and the substrate. Some protection
was afforded the substrate, especially against the #2 fuel oil.
5. f6 fuel oil was extremely difficult to renove frczn both treated and
untreated salt-marsh sections. Polyvinyl acetate and xanthan gun
eased the flushing of the oil fron the substrate in ooiparison with
control sections. "Hie xanthan gun, in particular, appeared to work
better than polyvinyl acetate in facilitating 16 fuel oil removal
frcni the substrate.
Surface Collecting Agents
Under the limiting conditions in which the beach and salt march surface
collecting agent tests were conducted, the following conclusions were drawn.
The surface collecting agent was effective in confining oil under
nonturbulent conditions. Turbulent conditions (caused by breaking waves
inpinging on the test area) caused the contained oil slick to break up. In
the absence of the confining barriers used in the test, this effect may not
have occurred. Oil washed into the marsh by turbulent conditions was easily
removed from the plants by low-pressure water flushing.
General
Permit stipulations on the conduct of the full-scale field program,
requiring that all test oils ba contained within and roioved fron the test
area, disposed restrictions on ths "real-wrld" evaluation of the agents
tested. Because of this restriction a great deal of effort was expended to
ensure that oil was contained within the surrounding boons. In the case of
the surface collecting agent test, this constriction interfered with the
actual roschanisn of the naterial being tested, that is, tha surface collecting
agent tended to drive oil away frcm tha shoreline which was counteracted by
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Toxicity testing of eight agents on Spartina foliosa (cordgrass)
including relative comparisons of plant reaction (e.g., health) to various
treatments made on the basis of qualitative observations arul quantitative
measurements of growth ratio were inconclusive.
Agent Toxicity
Toxicity testing of PVA and xanthan gum on juvenile callinect.es (blue
crabs) showed that:
1. The acute static bioarsay successfully established 96-hour toxicity
ranges for the two agents: PVA (0.45% to 3%) and xanthan gum (3% to
2. PVA (as applied at 100%) is seemingly more toxic to first-stage
juvenile Callinectes than is xanthan gum (as applied at 1%).
3. The PVA at 0.45% concentration did not have any apparent physiologi-
cal effect on the crabs during the 96-hour test period.
4. The xanthan gurrt at 3% concentration did not have any apparant
physiological effect on the crabs during the 96-hour test period.
5. The 96-hour TLM for PVA was 0.95%.
6. The 96-hour TIM for xanthan gum was 5.5%,
7. The PVA seemed to act like a weak acid. The persistent low pH level
in the 5% tank could have contributed to the toxicity of the agent.
Additional tests on the chemical behavior of PVA in water are
rcconwended.
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SECTION 3
PECOMMEN11WIONS
Based on the fir.di.rxjs of this study, the following recaitnendations are
offered:
1. Further research should be conducted to evaluate, under field
conditions, other types of potential surface protection agents
such as:
* additional tests with surface collecting agents
* dispersing agents
* new film-forming agents, such as high-density, low-expansion
foams or a polymeric high-expansion gel or foam
* polyvinyl acetate with formulation adjectments to make it more
readily degradable and to accelerate its drying tire
2. All three film-forming agents should also be evaluated for effective-
ness of protection against oil contamination on cobble and/or rock
beaches.
3. Laboratory tests should be conducted with new agents to define their
operation limits.
4. A prototype application system for beach and marsh areas should be
designed and tests on an oil spill of opportunity using polyvinyl
acetate as a surface treatment agent.
5. Additional testing in salt marshes is recommended to verify tests for
agent toxicity. Experience gained in the preliminary work should
permit development of refined and conclusive testing procedures.
6. Additional acute bioassay tests of PVA in the range of 0.45% to 3%
and xantham gum in the range of 3% to 1J?% should be performed en
first stage blue crab juveniles. Also, testing of post larval crabs,
generally regarded to be more sensitive than first stage juveniles is
recommended.
7. Organism toxicity of oil and oil plus agents should be determined on
crabs through additional bioassay testing.
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SECTION 4
FULL-SCALE FIELD TESTS
TEST SITE
The full-scale field tests were conducted at Sewaren Beach, located on
the New Jersey side of the Arthur Kill, between the PuMic Service power plant
on the north and the outlet of Snith Creek on the south (latitude 43 degrees
32 min. N, longitude 74 degrees 16 feet W) (Figure 1). Sewaren Beach is
approximately 670 meters long and has been zoned a park site by the town of
Vfcodbridge. The area is a former salt marsh that has been used as a disposal
site for dredge spoils by the Corps of Engineers. The shoreline is composed
primarily of gravel and coarse sand beaches interspersed with email patches of
salt marsh on the southern end. The northern two-thirds of the intertidal
beach area consists primarily of gravel; the southern third consists
generally of gravel in the lower intertidal area and sand in the upper
intertidal area, with scattered salt marsh in the foreshore area of the beach.
The land areas surrounding the Arthur Kill are heavily industrialized and
densely populated. The Arthur Kill is an industrial waterway and is a heavily
traveled conponent of the New York Harbor complex. Extensive dredging,
landfilling, and bulkheading havs eliminated rcuch of the natural shoreline and
wetlands.
Sewaren Beach is located along a section of the Arthur Kill that is
subject to frequent oil spills. In 1973 the Arthur Kill from Linden to Perth
Amboy was the scene of 147 separate oil spills, ranging in size from a few
liters to 336,£^0 liters of oil. Twenty-nine of the 147 oil spills were
greater than 378 liters and 11 were greater than 3,785 liters (USCG Polliition
Incidence Importing System). Because of the frequent oil spills in the area,
the sand and gravel on Sewaren Beach contain residual weathered oil from past
spills.
TEST OILS
Three types of oil wera used to test the effectiveness of the surface
treatment agents. The three oils present a wide spectrum of physical
characteristics and are representative of the wide variety of crude and
refined oils that could be accidentally released onto the water.
Characteristics of the three test oils are given in Table 3.
8
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•
i-ju^iy. 4< n«-n i
Figure 1. Location of test site.
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TABLE 3. CHARACTERISTICS OF TEST OILS
t2 Fuel Oil 86 Fuel Oil
Characteristic Min Max Min Max Arabian Crude
Gravity (°API) 32.1 42.8 11.0 16.9 35
Viscosity
Kinematic (100°F, CS) 2.35 3.0 ~ — 8
Furol (122°, SFS) — ~ 101 250
Pour point (°F) — 0 — 35 -20
Sulfur content (wt, %) — 0.35 — 2.73 2.5
Aromatics content {wt, %) 48 48
C. cut and lighter (wt, %) — — — — 2.88
AGENT EVALUATION FKOCEDURES
The full-scale field tests vere divided into two parts for the tv>o tasks.
The durability of ths film-forming surface treatment agents vas tested
initially. Each candidate agent was applied to a marsh and beach test plot in
the upper intertidal zone of the test site. Each test plot was observed and
photographed during a tidal cycle and was sanpled to determine the length of
time each candidate -?gent remained on the shoreline surface as a viable
surface treatment agent.
Ihe second and more ijinportant part of the test program involved testing
each candidate surface treatment agent for its ability to protect a shoreline
surface vhen subjected to contamination frcrn three different oils. This part
of the program was further subdivided into two parts: film-forming agents and
a surface collecting agent.
Film-Forming Agents
Test plots and control plots were laid out along a selected portion of
the upper intertidal zone of the designated rnarrh and beach test zones. Each
test plot was coated with a different candidate surface treatment agent, and
the control areas were left in thair natural state. Each beach test plot
measured approximately 9.2 square maters. Each marsh test plot measured
approximately 1.2 by 3 craters.
Beams ware deployed in ths water arojnd the perimeter of tha test zone.
10
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Just prior to the tidal ebb, a specified volume of oil was released en the
water inside the boomed test zone upwind fron the test plots. The ebbing
tidal action and prevailing wind deposited the oil on the surface of the
shoreline test and control plots. After the tide had receded fron the test
and control plots, data ware collected to assess the performance of each agent
in protecting the shoreline fron oil contamination. 1'ae conditions of the
test plots were compared with the conditions of the oil-contaminated control
plots. Following data collection, half of each oeach test and control plot
and the entire area of each marsh test and control plot on which oil remained
vKjre flushed with a low-pressure water system to determine the ease with <.'.hich
oil could be removed fron an agent-coated surface. The other halves of the
beach test and control plots were cleaned to determine if an agent-treated
surface increases physical cleanup effectiveness.
Surface Collecting Agents
The surface collecting agent was tested separately because it would have
affected the filn-forming agent tests on adjacent plots. Boons were deployed
in the water around the perimeter of the test zone, and the test oil (Arabian
crude) was released prior to tidal ebb inside of the bocmed zone. The surface
collecto:: was applied to tha substrate of the beach and marsh test plots using
an 18.9-liter hand-held garden sprayer, and it was also sprayed into the water
ahead of the approaching oil slick. Data collection was conducted in a
similar manner as for filir-forming agents.
DATA OXIECTION
Rvatography was the major data-collection technique and was used
primarily to record observations permanently. Photographs were taken of each
test and control plot before and after each test to determine the degree of
oil contamination. Depth of penetration of oil into the test plot VQS
determined by cutting sections across a test plot, taking filter-paper blots
at 7.6-on and 15.2-on depths, and examining the filter papers under
ultraviolet light to determine the presence of oil by its characteristic
fluorescence.
AGEOT APPLICATION EQUIPMENT
Four types of equipment were used in applying the surface treatment
agtnts during the full-scale field tests:
* hydraulic sprayer
* rotary pump
* water spray system
* garden sprayer
1.1
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Film-Forming Agent Application
Because a hydraulic sprayer was successful in applying film-forming
agents in the preliminary field tests, a hydraulic sprayer was used to apply
xanthan gun and polyvinyl acetate for the first day of testing. Problems with
the hydraulic sprayer occurred when tba high pressure of the sprayer caused
substrate disturbance of the beach test plots, and the nozzle of the sprayer
clogged as the agents were being applied, causing lengthy delays. Therefore,
the hydraulic spraying system was replaced by an alternative spraying system
for the rest of the tests. The alternative spraying system consisted of a
high-volune, positive-displacement, reversible rotary punp powered by a small
(5.85-hp) diesel engine. The punping rate was 64.4 liters/ minute at 1.75 to
2.1 kg per sq on (25 to 30 psi) at 1000 rpm. A 5.1-cm suction hose and a
1.6-on discharge hose with a hand-activated, adjustable piston-grip nozzle was
used to apply agents. This conbination provided a spray that gave an even
coating to the shoreline substrate over a reasonable amount of time. There
was no disturbance of beach substrate.
Water Film Application
The water-spray system was fabricated in the field; two 3-mater-iong,
3.8-an-diameter PVC pipe sections were joined by a 60-cm-long, 3.8-cm-diameter
fire hose. A 5.1-cm trash punp (60-100 liters per minute) was used to punp
salt water from a suction hose into the water-spray system. The 15-meter-long
suction hose was suspended beyond the surf zone, below the water surface and
above the bottom, to keep oil and bottom sediments from entering the
water-spray system. Initially, fan spray heads from underground lawn
sprinkling systems were inserted in the PVC pipe (30.5 cm apart). This
provided a fine spray that created a continuous film of water over the
substrate. These spray nozzles clogged with the algae and the suspended
sediment entrained by the purg? intake within several minutes. Holes measuring
1.2 on in diameter were then drilled into the PVC lips (30.5 cm apart). This
allowed water to flew freely frcrn the holes, forming a flowing-water film over
the beach and marsh.
Surface Collector Application
An 18.9-liter low-pressure (1.75 kg per sq cm, 25 psi) hand-cparated
garden sprayer was used to apply tha surface collecting agent.
TEST PROCEDURE
Table 4 gives the testing sch.»3ule and the environmental conditions at
the test site at the times of agent application for the 4 days of testing.
Figure 2 shows the test area, including ths four test zones and the specific
locations of the beach and mrsh test plots.
Xanthan gun and polyvinyl acetate were applied (using the application
techniques previously discussed) to tha beach and marsh test plots between lew
tide and nddtide and allowed to dry. The water-spray si's ten was turned on at
high tide and before tha test oil was spilled. Tna surface collecting agent
was applied to tha b&ach and narsh test plats and to the water in front of the
12
-------
TABLE 4. ENVIRONMENTAL CONDITIONS
Environmental
Conditions at
Agent Application
Time of agent application
to beach plots
Xanthan gum
Polyvinyl acetate
Water
Surface collecting agent
Air temperature
Wind speed
Wind direction
Water salinity
Height and time of high tide
Clou'd cover
Beach type
Area of beach plots
#6 Fuel Oil
May 21, 1977
0830
0900
1100
24-26°C
Less than
8 kph *
SSE
25-30 ppt**
1.4 m, 1100
Hazy
Sand with
some gravel
9.2 sq m
#2 Fuel Oil
May 23, 1977
0930
0955
1226
24-26°C
Less than
8 kph
SSE
25-30 ppt
1.3 m, 1226
10%
Sand and
gravel
9.2 sq m
Arabian
May 24, 1977
0950
1000
1315
24-26°C
8-16 kph
SSE
25-30 ppt
1.4 m, 1315
Hazy
Sand and
gravel
9.2 sq m
Crude Oil
May 25, 1977
1407
29-32°C
8 kph
SSE
25-30 ppt
1.4 m, 1407
Hazy
Sand and
gravel
9.2 sq m
* kph = kilometers per hour.
** ppt = parts per thousand.
-------
P • Potyvlnyl Aceute
X • Xmthtn Gum
W • Water Sprty
C • Control
H • Surtacs/Collectlng Agtnt
-
Plywood Barrier
•Mewl Stake /Boom
-a ——»
Plywood Barrier
Shoreline
*2M^
Durability Test
X P
test Zone
Arabian Crude
Sand
Sand and Gravel
3 Gravel with Sand
y Gravel with Sand and Mud
SaltMatsh
Figure 2. Location of test plots in four test zones.
-------
approaching oiJ slick after the test oil was spilled.
The test oils were spilled manually from an 1.8.9-liter bucket and vere
allowed to drift with the wind and current toward the test plots. Because the
high tide did not fully cover some marsh test plots, oil was forced toward
these plots by simulated wave action generated by a low-pressure water-spray
system. Ihis procedure was followed for.each test oil and continued until a
uniform coating of oil covered the vegetation and substrate. It was not
possible to contaminate each plot entirely, but enough of the plots were
covered to produce the desired results.
After completion of the tests, all test zones were cleaned manually with
sorbents and low-pressure water flushing. The beach test plots vere also
cleaned mechanically by a front-end loader, which removed the contaminated
beach material.
TEST RESULTS
Beach Tests
The major observations made and data collected during the full-scale
tests at Sewaren, New Jersey, are given in Tables 5, 6, and 7. Included are
;data for each test, including the agent-applicaticn method, the volume of
agent jsed, agent density (volume/sq meter) on each te^-t plot, the time
required to apply the agents, the time required for the film-forming agents to
dry on each test plot, the percentage of oil coverage on each test plot after
tidal deposition of the oil, and ccmnents on the performance of the agents and
the results of flushing oil frcm the agent surface. Drying tiroes of the
film-forming agents varied; pools of polyvinyl acetate and xanthan gum formed
in depressions on the bsach and took longer to dry because they were thicker
than the rest of the film.
Flushing of oil frcm the film-forming agents was first attempted using
sea water through a 3.8-on fire hose attached to a 5.1-cm centrifugal trash
pump. tfcwever, the pressure and volume of water was too great, and the
fire-hose stream broke up the polyvinyl—acetate film and flushed oil into the
sand substrate. A 1.6-on hose with an adjustable pistol-grip nozzle attached
to the same trash purrp was then tried. It successfully flushed oil fron the
agent's surface without rupturing the film. :
The effectiveness of each agent compared with a control in protecting the
beach frcm oil contamination is given in Table 8. Ibllowing each test, the
presence of oil on the surface of the test plots and the degree of oil
penetration were determined by visual observation and by a sampling technique
eniploying ultraviolet light. In this technique, vtiich was developed by TRI,
Whatiran f 1 filter paper was used to blot water froa the baach sediments at tha
surface and at 7.6-on and 15.2-cni depths. Each filter paper was then examined
under ultraviolet light for the characteristic fluorescence of the test oil,
and a semiqaantitative determination was mada of the amount of oil present. A
subjective assessment of tha degraa to \vhxch oil covered each plat was made by
visual observation. In the Arabian crude oil test, xanthan-gua,
polyvinyl-acetate, and flcwing-water-sheat test plots wsrc significantly less
15
-------
TABLE 5. SURFACE'TREATMENT AGENT BEACH FIELD TEST: $6 FUEL OIL
(volume spilled: 114 liters)
JVi*_'l't To;; t •:•
Application
rethod and
s;-ray pressu
Volume of agent
A-lvnt applica-
tion density
Tiv.c required
to spray agent
{nin or sec)
Agent drying
tine
viiiv 1 "fro La to
Hydreulic sprayer at
42 kg/sq cm (600 psi);
also poured atj&iit en to
test plot*
3*7 liters sprayed;
3.8 liters poured
1 liter/sq neter
10-15 ran
1.5-2 hr
Xnnthan
Control
Hydraulic sprayer at Continuous water flow
•S2 kq/sq en 0o at «iO-100 lit«_-rs/r:in
psi); aim injured
agent onto test plot*
15 liters sprayed;
19 liters poured
3.7 iiters/sq meter
20 min
1 hr
3-5 liters/sq ir*,-ter
Oil coverage on
test plot after
t€Et
Coments
Results of
surf act:.
flushing
lOOt of area covered
by tide
Agent film in lover
intertidal area of
test plot was dis
solved by tide before
it had properly dried
Flushing with a fire
hose ruptured poly-
vinyl acetate filn,
causing oil to pene-
trate beach substrate.
Flushing with garden
hose removed rost of
the oil froci poly-
vinyl acetate filn.
Film regained stained,
however.
40-501 of area cov-
ered by tide
Agent filn in lower
intertidal area of
test plot vas dis-
solved by tide
before it had
properly dried
Flushing reiroved
only some oil from
surface
20-30% of area covered 100% of area
by tide covered by tide
Flowing water eroded
channels in sane/
sections of test plot,
Oil did not adhere or
penetrate in areas
where water flowed but
did contaminate areas
where water film did not
cover due to ero&ion
chanrels
Oi1 not removed
by flushing
* The volume of aqonts sprayed by the hydraulic sp.-ayinq system was too small to use on a lan;e s-:.ile.
Therefore, a different, spraying system was used for other tests.
16
-------
TABLE 6. SURFACE TREATMENT AGENT BEACH FIELD TEST: #2 FUEL OIL
{volume spilled: 190 liters)
Agent Tested
Pglyvinyl Acetate
Xanthan Gum
Water Spray
Control
Application
method and
spray pressure
Volume of agent
used
Agent applica-
tion density
Time required
to spray agent
(rain or sec)
Agent drying
time
Oil coverage on
test plot after
test
Comments
Results of
surface
flushing
Viking gear pump and
1.6-cra hose with gar-
den spray nozzle at
1.4-2.1 kg/sq cm
(20-30 psi)
23-30 liters
2.S-J.3 liters/
sq meter
1 rain
1-1.5 hrs
100% of area covered
by tide
Host of oil flushed
from film by garden
hose spray
Continuous water flow,
60-100 liters/min
Viking gear pump and
1,6-cm hose with
garden spray nozzle
at 1.4-2.1 Jtg/sq on
(20-30 psi)
57 liters
6.2 liters/sq rooter 3-5 liters/sq meter
50 sec
45 min
loot of area covered
by tide
100% of area covered
by tide
Where water was flow-
ing on test plot there
was no oil contamina-
tion (sheen in other
area"); channel ero-
sion a problem
100%'o£ area cov-
ered by tide
Very little oil
removed with flush-
ing by garden hose
spray
Oil not removed
by flushing
-------
TABLE 7. SURFACE TREATMENT AGENT BEACH FIELD TEST: ARABIAN CRUDE OIL
(volume spilled: 95 liters)*
Application
method and
spray pressure
Voluno of agent-
used
Agont applica-
tion density
Time required
to spray ayent
(itiin cr iec)
Agent drying
time
Oil coverage
on test plot
after test
Corinents
Results of
surface
flushing
Polyvinyl Acetate
Gear pump and l.b-cm hose
with gard«n spray nozzle
at 1.4-2.1 k-3/sq cm
(20-30 pal)
15 Uteia
1.6 lite:s/sq meter
SO soc
1-2 nr
loot of area covered
by tide
Polyvinyl arofate had
loss surface oil con-
tamination than x an than
gum but more than flow-
ing water film
Successfully removed
almost all oil from
Xanthan Gun
Gear pump and 1.6-em
hose with garden
spray nozzle at 1.4-
2.1 ky/sq cm (20-30 psi)
57 liters
6 liters/sq meter
50 sec
1-1.5 hr
100\ of area covered
by tide
Morn oil on xanthan
gum tost plot than
Polyvinyl acetate and
flowing water film
Flushing removed some
oil from surface
Agent TVstod
watrr Spray Control
Continuous water flow
at OC-100 litcrs/min
~
3-5 liters/sq motor
— — • — —
•-
Less than 101 of area 100% of area cov-
covered by tide cred by tide
Flowing water film test
plot appeared to hava
least surface contanlna-
tion; loore gravels in
this tost plot, so ero-
sion vas less and there-
fore oil contamination
was less
Flushing did not
remove any oil
Surface? Collector
Sprflyed onto shoreline-
and into vjtnr ahead of
ap,jro. ching oil 9lic!:
1 liter
—
5 mi p.
—
100^. of area covered by
tide
* Tha surface collector was tested separately using 38 liters of Arabian crudo oil.
-------
TABLE 8. BEACH SURFACE TREATMENT AGENT COMPARISON
Oil
*6 Fuel
#6 Fuel
#6 Fuel
#6 Fuel
IS Fuel
K6 Fuel
ft 6 Fuel
»6 Fuel ,
86 Fuel
#2 Fuel
#2 Fuel
82 Fuel
«2 Fuel
»2 Fuel
»2 Fuel
«2 Fual
It2 F\sel
#2 Fuel
Arabian crude
Ar&bi&n crude
Arabian crude
AraJaian crude
Arabian crude
Arabia*! crude
Arabian crude
Arabian crudo
Arabian cru?i«
Arabian crude
Agent
Polyvinyl acetate
Xanthan gum
Water
Polyvinyl acetate
Xanthan gum
Water
Polyvinyl acetate
Xanthan gum
Water
Polyvinyl acetate
Xanthan gum
Water
Polyvinyl acetate
Xanthan gum
Water
Polyvinyl acetate
Xanthan gum
Water
Polyvinyl acetate
Xanthan gusn
Water
Polyvinyl acetate
Xanthan gum
Water
Polyvinyl acetate
Xanthan gum
Water
Surface
Collecting
figsat
Sample
Surface
Surface
Surface
7.6-cm cross-section
7.6-cm cross -section
7.6-cra cross-section
15.2-cm deep
15.2-ca deep
15.2-cm deep
Surface
Surface
Surface
7.6-cm cross-section
7.6-cm cross-section
7.6-cm cross-section
15. 2-cm deep
15.2-cm deep
15.2-cm deep
Surface
Surface
Surface
7.6-cm cross-section
7.6-cm cross-section
7.6-cm cross-section
15.2-cm penetration
15.2-crm penetration
15.2-cm penetration
Surface
7.6-cm cross-section
15.2-cra penetration
Presence of Oil (Comparison to Control)
Visual Observation
Ultraviolet Lictht Sanies (Surface Only)
Better Sarae Horse Better Some Worse
X X
x x
x x
X
x
X
X
x
X
X X
X X
X X
X
X
X
X
X
X
X X
X X
X X
X
X
X
X
X
*
x x
X
X
-------
contaminated by oil than the control plot. Hawever, surface sampling by
filter-paper blotting of these test plots indicated that the presence of
hydrocarbons was equivalent to or greater than that of the control. This is
because the ultraviolet-light detection technique do&s not discriminate
between high and low levels.
Tho beach-test results indicated that polyvinyl acetate was superior in
preventing oil from penetrating tha beach sediment. Although oil
contamination of the polyvinyl-acetate surface was greater in some casea than
for other agents, it proved to be the agent that could be cleaned most easily
by flushing with a low-pressure water system. The most difficult oil to
protect the beach against was 12 fuel oil; only polyvinyl acetate provided
protection against $2 fuel oil penetration.
The surface collecting agent initially was very successful in preventing
Arabian crude oil from reaching the beach test plot. The surface collecting
agent formed a barrier in the water in front of the test plot and drove th3
advancing oil slick back against the containment boom that surrounded the test
zone. A water stream from a fire hose vas used to hold the oil away from the
containment boon. After approximately 20 minutes, breaking waves impinged on
the test zone, causing the contained oil slick and chemical barrier to break
up into numerous small oil slicks, some of vAiich came ashore contaminating the,
test plots. Without the containment barrier, the surface collecting agent may
have held the slick offshore effectively.
Beach testa of the durability of tha film-forming agents, polyvinyl
acetate and xanthan gum, were also conducted during the full-scale field teat
program. Xanthan gum and polyvinyl acetate were each applied to a
10-square-mster test plot in the upper intertidal zone of the test site at
application densities of 6 liters per sq meter for xanthan gun and 3 liters
per sq mater for polyvinyl acetate. The xanthan-gun film was intact (i.e.,
maintained film integrity) after one tidal cycle, but had essentially
disappeared except for an occasional patch after the second tidal cycle. The
polyvinyl acetate proved much more durable and was still intact at the
1 of tha test prog*^1 four days and eight tidal cycles later.
DISCUSSION
Protection Effectiveness
The effectiveness of surface treatment agents in protecting bsach and
salt marsh areas from oil contamination varied with the type of oil spilled
and the type of beach.
Balyvinyl Acetate —
: Of tha four agents evaluated, polyvinyl acetate provided the most
effective protection from the three test oils. The use of polyvinyl acetate
substantially decreased oil penetration into the beach substrate as compared
with the control, although surface contamination was similar to the control in
two of the three tests. Balyvinyl acetate dried to a firm, serd-pliant film
that could be pesled almost intact frcm the beach surface. The agent can be
applied full strength (without dilution or mixing) at a rate of approximately
20
-------
10 sq meters per minute with a rotary purtp system. However, before it is
effective as a film-forming agent, polyvinyl acetate requires time to dry. If
it is still liquid or sard-liquid when it contacts water, it will dissolve
into the water col inn. Once dried, the polyvinyl acetate film is very durable
against tidal action and small waves. liowever, this is only true as long as
waves do not impijjge on the beach above the upper limic of the
polyvinyl-acetate film, where the wave backwash can get under the film and
destroy it«? integrity.
Xanthan Gun—
Xanthan gun was less effective than either polyvinyl acetate or the
flowing-water film in protecting the beach test plots from oil penetration,
although in the t6 fuel oil test there was less surface oil contamination of
the xanthan-gun-coated test plot than of the polyvinyl-acetate-coated plot.
Xanthan gum was applied in a 1% water solution (by weight) with the rotary
pump system, at a rate of approximately 10 sq meters per minute (similar to
polyvinyl acetate). It dried somewhat more rapidly than polyvinyl acetate to
a soft, jellyliXe film. Like polyvinyl acetate, if water contacts xanthan gun
before it dries, it will dissolve into the water cclurai. A xanthan-gura
protective film will last for approximately one to two tidal cycles before its
integrity is lost. Xanthan gun is cortnercially sold as a dry powder (used in
drilling mud) and does not dissolve easily, requiring mechanical stirring to
effect a solution. The xanthan-gun powder must be sifted as it is added
slowly to the vortex of the water or it forms clumps. It required
approximately 10 minutes to mix 113.6 liters of 1% xanthan gum solution.
Flowing-Water Film—
A flowing film of water was less effective than polyvinyl acetate, but
somewhat more effective than xanthan gum in protecting beach test plots from
oil contamination. Of all the agents tested, the water film provided the best
'protection from surface oil contamination, but it allowed more oil penetration
into the beach substrate than polyvinyl acetate.
The flowing film of water, applied at a rate of 3 to 5 liters per sq
naeter, tended to cause channel-type erosion on sandy sections of the test
plots. This erosion resulted in an uneven distribution of the water film
:(i.e., water flowed in the channels in the sand). The high spots between the
channels were not covered by tha water film, and thay became contaminated by
oil. If channelization had not occurred (as would be the case on gravel,
cobble, or rock beeches), the flowing-water film would have been an even more
effective protection agent. A recurring problem with the flowing-water systan
was clogging of the water distribution pipes and outlet holes by filamentous
algae and sadiment picked up by the water punp suction line.
Surface Collecting Agent
The surface collecting agent provided an effective chemical barrier that
prevented oil from reaching the shoreline until wave action disrupted ths
contained oil slick, allowing seme oil to be carried ashore. The inner oil
boon surrounding the test area vras only 5 to 8 rceters from tha high tide
lines. Ihis close boundary may have interfered vjith the evaluation of tha
surface collecting agent. Within seconds after applying tlie surface
21
-------
collector, the oil slick contracted into a narrow band against the inner boctn.
A water stream from a fire lK>se was used throughout the test to hold the
oil SJ.ick away from the boon. Hcwever, the contained oil slick was not broken
up until breaking waves passed through the test area. Once the slick was
disrupted into small oil slicks or spots, the v/ater stream and prevailing
winds helped carry seme of tlie oil ashore.
Oil-Contamination Sampling
The ultraviolet-light detection technique used to determine the
penetration of the agent by a test oil is extremely sensitive to the aromatic
hydrocarbons present in oils, especially light fractions. As performed, a
blot sample is taken from the beach on a VSiatman #1, 9--cm-diameter filter
paper. This filter paper absorbs aromatics if present in even a small
quantity. Subsequent examination of the paper under short-wave (2500 A )
ultraviolet light vd.ll show a characteristic fluorescence only in the area of
test paper contacted by the oil.
This test is semiquantj.totive in nature. It will not accurately
determine quantitative amounts of oil penetrating a beach, but will show the
degree of presence or absence of the oil. Also, the source of oils detected
;is not specific to those spilled. Any contamination present in the beach
strata fron earlier spills may be detected. Test samples taken from the
Sewaren Beach test site prior to agent testing in fact showed detectable
levels of oil.
The following conclusions can be nde from the results of the blot tests:
* All beach samples examined showed the presence of oil under the
surface prior to the test series. Surface examination showed no oil.
* Comparison of visually observable surface contamination to blot-test
penetration samples may not correlate because of blot-test
sensitivity and the colorless nature of light components of the oils.
* General trends of effectiveness can be determined from the combined
results of visual and ultraviolet observations.
Effectiveness of Surface Oil Removal ;
The degree to which the xanthan-gun and polyvinyl-acetate-ccated beach
test plots could be cleaned of surface oil contamination was evaluated for the
three test oils. This evaluation was undertaken to determine if the
agent-treated surface affected tho effectiveness of cleanup operations.
Low-pressure water flushing was employed to clean oil from the agent's
surface. In all three cases, the polyvinyl—acetate film was cleaned more
effectively than the xanthan-gun film. The fuel oil that was the most
difficult to flush was #6 fuel oil; very little was removed fron the
xanthan-gun surface and an oil stain remained on the polyvinyl-acetate film
after flushing.
22
-------
A brief test was performed on the polyvinyl-acetate and xantlian-gun test
plots to determine if the use of these film-forming agents would make cleanup
of oil-contaminated beaches by heavy equipment easier. A small rubber-tired
front-end loader, using its powered bucket as a scraper, dragged the bucket
across each beach tost plot. The xanthan-gxrn film broke up and did not
enhance removal. The polyvinyl-acetate film was peeled from the beach
surface, making surface cleanup easier.
Salt Ffarsh Tests
Each test plot was exposed to approximately one-eighth of the total
volune of oil spilled.- There were four marsh test plots tested with each oil
and, depending on the total voluwe of oil spilled, each plot was exposed to 12
to 15 liters. The results of tie marsh tests are sliown in Tables 9, 10, and
11.
All of these test results are based on observations made during and
shortly following che application of agents and oils. In the tables,
short-term effectiveness refers to observations made during and immediately
following each test. long-term effectiveness is based on a composite of
observations node each day for 3 days after a particular test. Agents are
ranked according to their relative effectiveness, for the Arabian crude oil
test, the ranking ranged from 1 to 3 and compared the agents with each other.
An additional evaluation was made in order to determine whether the
agent-treated test plots produced results better than, worse than, or the saoie
as the control test plot.
#6 Fuel Oil-
Four 1.2- by 3-neter marsh plots of Spertina altemi flora were marked off
for testing with 16 fuel oil. Approximately 14 liters cifbil contaminated
each marsh plot. The test plots consisted of a control plot, a plot treated
with approximately 10 liters of polyvinyl acetate, a plot treated with 30 to
35 liters of xanthan gum, and a plot that used a continuous water film as the
.surface treatment agent. Because of initial problems with tha application
system, the polyvinyl acetate and xanthan gun vrere applied by both spraying
and pouring the agents onto the marsh plot. Table 9 summarizes the results of
this test.
' Xanthan gum appeared to provide the roast effective protection for tha
short terra (iinnediately following contamination). Oil was easily removed from
the substrate by flushing with low-pressure water. This is in contrast to a
fair to good flushing result in the polyvinyl-acetate-treated plots and faiv
removal from the control plot. Extensive adherence of the oil to tha
vegetation was observed with all three agents and the control, with little
distinguishing differences. The xanthan gun was essentially 10-3% removed by
lorf-pressure flushing on both the vegetation and the substrate. Observations
of the test plot the day after the test revealed little or no agent present.
Ihe water-spray system did not provide complete protection because
obtaining a uniform flow over the substrate and the vegetation was difficult.
The primary effectiveness of the water spray was on the substrate, but as
noted, it was limited. Another prdbloa with the water-spray system occurred
; 23
-------
TABLE 9. SURFACE TREATMENT AGENT MARSH FIELD TEST: #6 FUEL OIT,
(volume spilled: 114 liters)
to
Ease of
Oil Removal
Soil by. Flushing
Agent
Folyvinyl
acetate
Xar.than
9Uffl
Control
Penetration Substrate
Pone Fair to qood
observed rciroval:
required
extensive
flushing
None Good re-
obtfcined
*one Fair re-
observed moval;
patches
difficult
to flush
Duration of Protection
(Nonturbulent 1
Vegetation
Poor removal i
extensive
oil ,1'lher-
encei approx-
imately 50-75*
remained
Poor removal;
adherence
Poor removal;
extensive
adherence
Degree cf Agent
Removal by Flushing
Substrate
Integrity of
film disrup-
ted; approx-
imately 50-
751 remained
Most or all
removed
after flush-
ing
N.A.
Response to Waves
(Turbulent)
Vegetation
Eome film dis-
ruption; Croat
still remained
Most of agent
flushing
N.A.
Corwicnts
Relative
Natural Deterioration Ktfetliv»ne» Comparison
>5f Aicnt (After Flushing) Short
Substrate
Slow; approx-
imately 501
still visible
after 3 days
Rapid; agent
rapidly re-
moved by waves
and tides
N.A.
Vegetation Term
Very slow) none 2
observed dur-
ing test; peel-
ing off in 1-2
days
Rapid removal 1
and tides
N.R.
Lonq to
Tern Control
1 Better than
control
2 Better than
-
Unlimited
Splashing has a ten-
dency to deposit oil
behind spray system
rrovcetion wai not complete) difficult to
obtain a uniform flow; primary effective-
ness on substrate
No difference
-------
TABLE 10. SOBPACE TREATMENT AGENT MARSH FIELD TEST: ARABIAN CRUDE OIL
(volume spilled: 95 liters)
i—— ——•*—-»
Age/ jit
Polyvinyl '
ace Cat a
Xanthan
gum
Control
-««,«^r,-.«*«fcr — :
Soil
Penetration
None to lim-
ited; lacK
of penetra-
tion may
reflect
completeness
None to lim-
ited; lack
of penetra-
tion nay
reflect film
completeness
Yes; par-
ticularly in
upper 2-4
cm
*.***..... *.,,, — , — - — ««-^^,-. — «
£aa« of Oil Removal
by Flushing
Substrate Vegetation
Fair to good Nearly complete
renewal.; de-
pendent upon
aucta.cc Ir-
regularities
Fair to good Nearly complete
removal F
dependent
upon surface
irregulari-
ties? rUght-
ly better
than poly-
vinyl acetate
Only fair Fair to good
rorrtoviLi
only on
surface
;.„.,. ™r^..--~.<..- .jr. «;££=,:=,
Oaqrifo of A'lant
npirovftl by Flushing
Sufcstr'Ste Vegetation
Integrity of ^omo Tilm di»-
film disrup- ruptionr mo.it
tedj 50-751 atill
rcTr>ai^cA T?:r>ai»tf-d
Most of agent Most or all
removed by of aqent rc-
flushirgi moved rap-
idly by waves
«md tid&s
N.A. N.A.
Duration of Protection Response to Waves
(Wonturhulent) (Turbulent)
* J<*
-------
TABLE 11. SURFACE TREATMENT AGENT MARSH FIELD TEST: #2 FUEL OIL
(volume spilled: 190 liters)*
N)
Agent
Poly vinyl
acetate
Xanthan
gum
Control
Soil
Penetration
None to lim-
ited; film
v<:ry com-
plete, lim-
ited pene-
Nonc to lim-
ited; but
oil may
penetrate
during
flushing
Yes
nf 1 DAIHAU. 1
by Flushing
Substrate
Good; most
oil easily
flushed out
Fair; oil
m«y pene-
trate dur-
ing flushing
Poor i only
oil on aur-
face
removed
Duration of Protection
(Nonturbulent)
Water spray
Unlimited
Von* tat ion
Good; most oil
easily
flushed cff
Good; shiny
appearance
reduced or
disappears
Fair to good;
shiny leaves
indicate oil
still present
after flushing
Removal bv Flushing
Substrate
Integrity of
film'dis-
ruptedr 50-
75% remained
Most of
agent
removed
N.A.
Vegetation
Integrity of
film dis-
rupted; 50-
75* remained
Most or all
of agent
removed by
flushing
N.A.
flelauve
of Anent (After Flurhina) Short
Substrate
Slow; approx-
imately 50%
of agent re-
mained after
3 days
Rapid; agent
not flushed
rapidly re-
moved by tides
and waves
N.A.
Yea-nation T*rm
Slow; agent 1
began to peel
off in 1-2
day*
Rapid i agent 2
not flushed
rapiJly re-
moved by tides
and waves
N.A.
Lcnq to
Tern Control
1 Better than
control
3 Better than
control
-
Responses to Waves
(Turbulent)
Splashing has A
doncy to deposit
behind spray
ten-
oil
Protection wae
Comments
not complete; difficult to 3
obtain a uniform flowi pr^niry
ness on substrate; works better
ef foctive-
than on *6
2 Better than
control
fuel oil, especially to limit substrate-
penetration
* S'rcaence of thin fllas of oil was extremely difficult to detect visually on both plants and luhstrato.
-------
during periods when large waves were generated by passing tugboats. The waves
had a tendency to transport and deposit the oil behind the flowing film,
partially negating the effect of the film.
Flushing with iG^pressure salt water caused disruption of film integrity
on the substrate of the polyvinyl-acetate plot; approximately 50% to 75% of
the film remained. Most of the film remained on the vegetation after
flushing, and the cordgrass retained its brittle texture. After one to two
days natural deterioration by waves, wind, and tide began to cause peeling.
Approximately 50% of the polyvinyl acetate was still visible on the substrate
after three days, although it was slowly hydrolyzing.
No substrate penetration by 16 fuel oil was observed for either treated
or control marsh plots. This was due primarily to the high viscosity of the
oil and the low porosity of the substrate.
Each film-forming agent was ranked in terms of its effectiveness in
protecting the salt marsh fron contamination by 16 fuel oil. The xanthan gun
was ranked first because of the slightly better results obtained when flushing
the substrate. Polyvinyl acetate was ranked ahead of the flowing film of
water because of the problems with the oil depositing behind the spray system
during periods of high waves.
In comparison with the control plot, use of the polyvinyl acetate and
xanthan gun proved more effective than no protection at all. In particular,
removal of the oil fron the substrate was enhanced by using the two agents.
The water film was also slightly better because it prevented the oil fron
adhering to areas where the vater was flowing. Because of the- nonuniform flow
on substrate and vegetation and problens with tha waves depositing oil behind
the spray, the water-spray plot was considered little different frcm the
control plot.
Arabian Crude Oil-
Five 1.2- by 3-neter marsh plots of Spartina were used to conduct the
tests with Arabian crude oil. In addition to the polyvinyl-acetate,
xanthan-gum, control, and water-spray plots, another plot was tested using the
surface collecting agent. Table 10 summarizes the results of the Arabian
crude oil test.
Each marsh plot was exposed to approximately 12 liters of oil. The
pal/vinyl acetate and the xanthan gun were applied with a rotary purnp. More
of each agent (approximately 15 liters of polyvinyl acetate and 57 liters of
xanthan gun) was used in this test. The water-spray system was the same
system used in the #6 fuel tests. :
Xanthan gum and polyvinyl acetate provided the most effective marsh
protection of all the agents tested, but xanthan gun appeared to work slightly
better than the polyvinyl acetate in enhancing flushing of the oil frcsn the
substrate (similar to tha 16 fuel oil tests). Both agents were successful in
providing nearly casplete protection for the vegetation fron oil after
flushing; removal of oil from the substrate and vegetation was only fair to
'gocd.cn the control plot. This indicates the effectiveness.of the polyvinyl
27
-------
acetate and xantban gun as surface treatment agents.
The water-spray system did not provide complete protection because of the
lack of uniform water flow over the substrate and the vegetation. Y&ves
generated by passing tugboats transported and deposited oil behind the spray
system. Water spray was most effective on the substrate in vAiich the water
flow prevented penetration of the substrate and adherence to the vegetation.
Flushing wirh low-pressure water spray caused diuruotion of the
polyvinyl-acetate film on both the substrate and vegetation, especially on the
vegetation. Ihe brittle texture of the plants indicated that most of the film
still rar*ained on the vegetation. After three days, approximately 50% of the
polyvinyl acetate remained on the substrate, indicating the slow natural
deterioration of the agent. Ihe leaves snowed signs of the polyvinyl acetate
peeling off after one to two days.
Xanthan gua was easily flushed from both the marsh substrate and the
vegetation imaediately following contamination by the oil. The residual
xanthan gum disappeared rapidly after one tidal cycle. This shows that
xanthan gun does not provide any lung-lasting protection.
Polyvinyl acetate and xanthan gun appeared to prevent significant oil
penetration into the substrate. Observations under natural and ultraviolet
light indicated that penetration was extremely limited. In contrast, the oil
penetrated the upper 2 to 4 era of soil in the control plot. Ihus, polyvinyl
acetate and xanthan gum did provide protection against significant oil
penetration ccn^ared with tl*e control plot. Ihe water spray system appeared
to prevent penetration in those areas of ths plot where the water flow was
continuous, but areas left unprotected ware affected in a manner sJinilar to
the control plot.
Xanthan gun was ranked as the best short-term surface treatment agent for
Arabian crude oil because it worked slightly better tlian polyvinyl acetate
when the oil was flushed fron the svabstrate. Over the long terra (a 3-day
period), polyvinyl acetate proved the most effective because it persisted.
The water spray system was ranked third because of ths limited protection
affbrdad.
The surface collecting agent was tested using Arabian crude oil only.
The application rosthod consisted of sprayitig approximately 1 liter of the
agent into the water ahead of the approaching oil. In calm water, the agent
kept the oil from advancing toward the marsh plot, contracting the slick
seaward against the inner bocm. Turbulence caused by vjaves broke up and
dispersed the slick, and s:me of the slick washed shore. Cnce in droplet
form, attempts to reunite the slick with more of the agent were unsuccessful.
In addition, the oil droplets were difficult to recover with the typa of
polyethylene sorbents used.
$2 Fuel Gil—
Tha £2 fuel oil tests were conducted using four 1.2-by-3-W2ter marsh
plots. Using the rotary puntp, approximately 23 liters of polyvinyl acetate
wsre sprayed on one plot and 57 liters of xanthan gixn on another. Ihe other
28
-------
two plots were a control and the water-spray section. In all, 190 liters of
12 fuel oil ware used in this test, which meant that each marsh plot (and
beach plot) was exposed to an average of approximately 24 liters of oil.
Water was used to force the oil onto the salt marsh because of the relatively
low tide. Consequently, as in the other tests, only the outer marsh fringes
were exposed to the #2 fuel oil. Table 11 summarizes the results ot this
test.
In contrast to the 16 fuel oil and Arabian crude oil tests, polyvinyl
acetate was found to be the most effective agent in protecting the salt marsh
fron #2 fuel oil contamination. Most of the oil was readily flushed from the
substrate and vegetation immediately following contamination. Flushing the
xanthan-gun-treated plot appeared to enhance oil penetration into the
substrate by removing the protective layer of the agent. This was not the
case with the polyvinyl-acetate-treated plot. Polyvinyl acetate appeared to
provide an effective protective film. The control plot had extensive
substrate penetration.
Both polyvinyl acetate and xanthan gum were effective in preventing
accumulation of the oil on vegetation. After flushing, the shiny or oily
appearance had been significantly reduced or had disappeared. The control
plot, on the other hand, still appeared shiny even after flushing, indicating
the persistent nature of the oil.
Flushing the polyvinyl-acetate- and xanthan-gum-treated plots with
low-pressure water caused the polyvinyl-acetate film to be disrupted on the
svibstrate and most of the xanthan gum to be flushed from both tha substrate
and vegetation. These observations are similar to those for the 16 fuel oil
and Arabian crude oil tests. The natural deterioration of .both of these
agents was also the same as that observed in tha other tests; the polyvinyl
acetate was persistent, affording at least 50% protection over a 3-day period
on both substrate er»l vegetation, while the xanthan gum had all but
disappeared after one tidal cycle.
The water-spray system did show scaie premise in preventing oil substrate
penetration in those areas where water flow was uniform. However, as before,
the protectioii was not. complete because of the inability to achieve a uniform
,flow on the irregular, substrate. The water-spray system did appear to work
better with the f2 fuel oil than with either the 16 fuel oil or the Arabian
crude oil because of the lighter nature of the oil. large waves did cause
transport and deposition of sane of the oil behind the spray, but this was
observed in all oils tested. Little protection '-as provided to the vegetation
except near the base of the plant.
The three marsh plots protected by surface treatment agents were not as
contaminated as the control plot. The most effective agent over both the
short and long term was polyvinyl acetate. By providing an effective barrier
after drying, and consequently maintaining at least 50% of the film over a
3-day pariod, polyvinyl acetate shows premise as a surface treatment agent.
Xanthan gufn prevented significant oil penetration during the short term, but
upon flushing and removal of ths agent, oil that raiainad or was rexntroduced
in the next tidal cycle was able to penetrate the substrate. Ebr this reason
29
-------
the water-spray system, which can be left in operation for long periods of
time, was ranked above xanthan gum as a long-term agent for marsh protection
from #2 fuel oil.
SUMMARY
Of all agents tested, polyvinyl acetate shows potential for providing the
best overall protection from all oils tested. The #6 fuel oil and Arabian
crude oil tests suggest that xanthan gun works, best as a short-term agent and
polyvinyl acetate best as a long-term agent. For 12 fuel oil spills,
polyvinyl acetate appeared to be both the best short-term and the best
long-term agent to use. Over Ihe long term, the water-spray system appears
more effective against #2 fuel, oil than xanthan gum because of the
recontaminatLon problem encountered when xanthan gum is flushed.
Polyvinyl acetate was more persistent than xanthan gun on both the
substrate and marsh vegetation. Xanthan gum had almost completely disappeared
after flushing and one tidal cycle. Polyvinyl acetate was still at Least 50%
present on the substrate and 50% to 75% present on the vegetation 3 days after
application. Because the water-spray system could be used continuously, it
would have to be considered the most persistent of any agent tested. However,
because of the irregular topography of the marsh, a uniform water film was not
possible. Ihis was especially true for the vegetation; it was very difficult
to spray the entire plot so that all plants were covered. Therefore, the
primary effectiveness of the water spray was on the substrate, and its best
use was against t2 fuel oil. ;
The surface collecting agent was tested with Arabian crude oil only.
Under nonturbulent conditions the surface collecting agent effectively
prevented oil from coning ashore when it v.ss applied just in front of the
advancing slick and to the marsh. When wave-induced turbulence occurred the
contained oil slick broke up into small spots and the collective effect could
not be reestablished by reapplications of the collecting agent and the
vegetation became contaminated. The oil-absorbing properties of the
polyethylene sorbent were affected by the surface collecting agent and oil
adherence to scrbent vas impaired. However, the oil-contaminated vegetation
was easily cleaned by low-pressure flushing and the surface collecting agent
appeared to reduce oil adherence to marsh plants.
Protection Effectiveness
Four major criteria ware applied in the evaluation of the relative
effectiveness of polyvinyl acetate and xanthan gun:
* degree of substrate penetration by the oil
* ease of removal of the oil by flushing
* rotcwal of agent by flushing
* natural degradation of the sgent over tima
.•;-.. 30 . ..
-------
The last three criteria were used in the evaluation of agent
effectiveness on the marsh substrate and vegetation of Spartina alterniflora.
Since no agents were applied to the control plot, only penetration and oil
removability could be used as criteria.
The water-spray system and the surface collecting agent were evaluated
according to criteria different from those for polyvinyl acetate and xarithan
gum because of the nature of the application and the rneans of protection
afforded. Each is designed to prevent oil frcra reaching the marsh grass. The
criteria used to evaluate these agents was their effectiveness under
nonturbulent and turbulent water conditions.
Modifications
Modifications will be necessary to make the water-spray system more
effective in preventing marsh contamination. TVte spray should be nore uniform
in order to protect both the vegetation and the substrate from oil
contamination. The system should be designed in such a way tl«at the nozzles
or water openings cannot be clogged by sediment picked up by the intake hoses.
A solution to both problems may be provided by a water diverter placed over
the open holes in a pipa. If such a system could be designed, water spray
might prove to be an effective, efficient, and inexpensive means of protecting
salt marshes. However, if a spill threatened a long expanse of slioreline, a
spray system would require a rather elaborate distribution systaa. Deployment
of such a system would be another problem.
For applications of polyvinyl acetate or xanthan gum on a larger scale,
development of a higher-volume application system may be necessary. The
experience gained using the rotary pump indicates that such a system could be
designed.
A polyvinyl-aoetate formulation that would decrease the drying time on
wet marsh substrates and vegetation should be investigated. In the event of a
spill, it may be necessary to have tha agent sprayed on and dried in a short
period of time. 'Jhis would ba particularly ijTgportant under cloudy sky
conditions. VSien the sky is overcast, tha temperature cool, or a slight
drizzle falling, drying time for the polyvinyl acetate is extended
considerably. Rilyvinyl acetate must cure and acquire a plastic consistency
to provide marsh protection.
31
-------
APPENDIX A
LITERATURE REVIEW
SURFACE TREATMENT AGENTS
A literature survey was conducted by Texas Research Institute, Inc.
(TRI) to provide a basis for analyzing the results of previous tests of
surface treatment agents and comparing their effectiveness. Sources of
information included the final reports of four previous API-sponsored studies
(by Exxon, Shell, and Tracer), other reports, technical product bulletins, and
personal connunicationa with suppliers and otlier informed individuals. It was
frequently impossible to objectively ccnpare the agents and methods used in
the previous work because of different testing techniques. Iherefore, vAiere
possible, estimates and judgments made by TRI on the previous work ware
substituted for hard data so that relatively conplete data on each agent could
be presented and compared.
The nine surface treatment agents reviewad are listed below. (In the
initial phase of this study 10 surface treatment agents ware suggested for tha
literature review. The tenth agent, polyvinyl acetate with a degradation
accelerator, was to have been developed through an expanded scope of the
program. This was not undertaken.)
* polyvinyl acetate (Borden Polyco 694)
* xanthan gum (Biopolymar 9700)
* citrus pectin
* Microooecus cerificans
* sodiun silicate (waterglass)
* borate-silicate mixture
* surface collecting agent
* dispersing agents
* water
All of the surface treatment agents were conpared (using data compiled
fron the literature review) for nechanisn of action and effectiveness on the
32
-------
substrates on which tney were tested and for limitations on use imposed by
climatic factors and environmental impact.;. A surraaary of the results of the
literature survey is given in the following paragraphs and shown in Table A-l.
Polyvinyl .ficetate
Polyvinyl acetate is available in a 55% aqueous suspension that can be
sprayed without dilution from a spraying system. For an effective solid film,
the coating roust dry to ollow the film to cure. This means that ultl-nate
solidification will not occur in wet weather. The cured film is highly
effective in preventing oil staining or penetration; it is quite stable and
lasted for several days under the wave action of the test, conditions. When
sprayed, the material gives a milky-white color to the test beach. Upon
drying, the film is clear and firm; rocks and wood appear varnished,
towever, the film will turn white if it becanes wet.
Xanthan Gum
Polysaccharide/xanthan gun is a high-molecular-veight biopolyroer produced
by fermentation by the microorganism Xanthomonas campestris. It is available
commercially in dry form or in a concentrated solution. In tests it was
sprayed on as a 0.5% aqueous solution and allowed to dry. Xanthan gun forms a
"soft" film because it is swollen with water. Such a hydrophilic film is not
attractive to oil staining and penetration. However, because of the
hydrophilic nature of the film, it is easily washed away. Exxon reported that
most of the film was washed off by wave action within an hour. It was tested
on river rocks and marsh grass and was judged to be effective in protecting
them against oil contamination.
Citrus Pectin
Polysaccharide/citrxis pectin is a coiplex carbohydrate with limited water
solubility but with water-attracting groups. Ihe mechanism of action of
citrus pectin is similar to that of the xanthan gum. A 1% solution waa
sprayed on river rocks and marsh grass in the lab tests. Ihe advantages and
disadvantages of citrus pectin as veil as the test results are essentially the
same as those for xanthan gum.
Borate-Silicate Mixture and Sodion Silicate
Borate-silicate mixtures and sodiun silicate were investigated separately
by Siell Developisnt Company. Both vrere found to be effective in protecting
rocky beaches. S\ell did not reccnroend borates because of reports of its
toxicity to aquatic flora. In Shell's testa with sodium silicate and sodiua
borate, l%-3% solutions of each ware sprayed on scale beaches. Ihe agent
.dried to forra an irorganic film, lha film was not attractive to oil but was
readily wet by water and was effective in protecting recks, but not sand. To
be effective, the film must have time to dry; this limits its application.
However, when silicates and borates are sprayed on sand wet with ocean water,
they form a soft gelatinous film that ray be effective in protecting sarrfy
beaches. This approach was not fully investigated. Ibe silicates form highly
33
-------
TABLE A-l. SUMMARY OP RESULTS OF LITERATURE REVIEW OF SURFACE AGENTS
Agent Typo
flechani sm
Form/Application _
Possible LiMitatlons
Sand
r e v i pus 1 ny e »t i gat 1
Rock« • "Marsh Gracs
Folyvinyl
acetate
Surface
collecting
agent
Dispersing
agent
Xanthan
Citrus
pectin
Sotiite-
silicate
mixture
Synthetic polymer/cone. (55%)
aqucoun suspensions; sprayed
on, high-prossuro. airless
sprayer; available dry
Long-chain alcohols in organic
solvent (watar insoluble)
Solid film
Has greater
spreading force
than oil: liquid
rnonomolecular
layer
Adjusts inter- Nonionic detergent/aqueous
facial surface solution (6%)
tepsionj dovulops
micelles of oil
in water
Soft polar film
Soft polar filn
liprayod on, dilute (0.5») aque-
ous solution; available a* dry
pcvder or concentrated solution
Sprayed on, dilute (1\) aqueous
solution; available ai dry
powder
Solid film (if Inorganic coating, diluted (1-3%)
cured) oquooun solution; sprayed on
color, rainy/freer- Effective
ing weather, must have 1 hr
to dry before it is effective
Short duration* loss of of*
fectiveness, might nood
continuous supervision
Effective in lab
and beach tests
Must be applied directly to Not tested
oil, large volume required
Short duration, 1 hr drying Not tested
time necessary
Short duration, 1 hr drying Not tested
time necessary
Toxiclty?, pit, drying tiiw Not effective
Effactive
Not tested
Effective in lab Not tested
and beach tests
{less effective
on dry rocks)
Not tested
Effective on
dry rocks
rocks but less
effective than
x*nth«n gun
Uff-ctivo
Not tested
Possibly
effective
Effective en dry Possibly
effective
Not touted
Sodiun
silicate
Solid barrier
(if cured)
Kicrococcus UnJcnown
cerificans
Water film Liquid film
Inorganic coating, dilute (1»)
aqueous solution; sprayed on
Frecze-dried, <3*) aqueous sus-
pension; sprayed on, garden
sprayer
Sprinkler systeca
Toxicity?, pH,
necessary
drying tin*
Not commercially available,
large preparation effort.
half life, drying
Continual application re-
quired (countercurrent) ,
equipment costs
Not effective
Not tested
Not tested
Effective
Not testod
Effective on dry Not tested
rorXa, less ef-
fective than
Not tested
Not tested
-------
alkaline solutions, which may be.an environmental problem.
Micrccoccus Cerificans
The soil bacterium Hicroooccus oerificans was cultered by Exxon
researchers and tested in three forms - live, freeze-dried, and spray-dried.
Only the spray-dried form could be seriously considered because the other two
pose storage problems. The spray-dried material was applied to rocks as a 3%
aqueous solution and was moderately effective in protecting against oil
contamination. Its mechanism for protection was not explained. The material
was not effective in cleaning rocks previously contaminated with heavy oils.
Microcoocus cerificuns is not available in ccranercial quantities. "Riis, along
with its lack of effectiveness, essentially eliminated it from further
consideration as a surface treatment agent.
Surface Collecting Agent
; A surface collecting agent is highly effective in limiting the spreading
of oil over water by forming a mononolecular layer on the water surface. The
chemical is sprayed directly onto the beach or into the water between the oil
and the teach. It may be applied in wat weather, but it solidifies at 2.2°C,
which places a low-teanperature limit on its use. It is effective in
protecting sand and wat beaches, but less effective in protecting dry rocks
and wood. It also appears effective in cleaning previously contaminated
beaches. Its protection is of short duration, and it must be applied after
each high tide.
Dispersing Agent
A nonionic dispersing agent uses the agitation of the surf to mix the
dispersant with oil and water and its use is rarely limited by weather
conditions. Ihe mechanisa of action depends on the dispersant interacting
with oil to form dispersed oil micelles. It was reported that this dispersant
is thought to be effective because it disperses the oil and carries it back
out to sea in the undertow before it can adhere to the beach. It is possible
that almost continual application will be required.
Flowing Film of Water
All of the API reports on chemical-agent shoreline treatment methods
mentioned that oil doss not stain wet beaches or rocks. Indeed, most
contamination of beaches occurs when oil is stranded by receding tides and
left on the upper intertidal zons. This would suggest the use of an
oleophobic mechanien of shoreline protection - wetting all surfaces to form an
oil-repelling liquid film. A sprinkler system could be used to keep a
continual countercurrent of water wsttirig a shoreline and washing oil back
into the surf. Although this method has not been evaluated specifically as a
surface treatment agent, a flowing film of water shows sons premise for
protection of shorelines from oil contorrtination.
35
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INFLUENCE OF CLIMATIC CONDITKXCS
Table A-2 details the influence of climatic conditions en each of the
surface treatment agents. Judgments by TRI were based largely on the previous
laboratory experiments and logical extrapolations from these experiments. For
instance, rain is obviously detrimental to materials that must dry to form a
film or that are quite soluble and easily washed away. Low temperatures
(freezing) prevent the spraying of aqueous solutions and the curing of the
film-forming agents. Likewise, low temperatures prevent the use of the
organic-solvent-based surface collector because it solidifies below 2.2°F.
Thus, none of the surface treatment agents considered here is readily
adaptable to cold climates.
Tidal and wave action is especially detrimental to the collecting agents
and to the more soluble agents, such as the polysaccharides, but aids
dispersing action. Hence with some agents treatment will be needed at least
after each tidal cycle.
High winds are a problem for all agents because they interfere with spray
application.
EMVTICNMHrcAL IMPACT OF AGENTS
Table A-3 presents the probable environmental impact of each of the
surface treatment agents. The "Appearance" colunn refers to the visual effect
and feel of the agent on the shoreline, i. e. , whether it modifies the
appearance and texture of the shorelline enough to be aesthetically
unacceptable. Toxicity data vcere taken from published reports and technical
information and include references both to organisms on the shoreline and to
people who apply the agent. An additional factor in toxicity is ths secondary
effect of the agent. For example, if the coating is impern?eable to air and
water and if the agent is not toxic, subsurface species can exist. The
surface collector tested is listed as low in toxicity because only small
quantities are allowed by regulation to be used; the concentrated solution
requires care and protective clothing for the application process. The
toxicity of borates and silicates is sonewhat questionable; however, it is
doubtful that their toxicity is high enough to be of concern once the film has
cured.
Estimates of the duration of the agents on the shoreline after the need
:for shoreline protection is over are based largely on laboratory experiments
done in the previous studies. Thus it is impossible to accurately predict the
duration on a natural shoreline subjected to sisi, wind, rain, surf, tides, and
other factors. The solid film-forming agents might last for several days or
even weeks. The soft film-forming agents and surfactants would probably be
washed away by surf action within hours.
'APPLICATION TECHNIQUES,
In the previous studies, agents ware either sprayed or poured on tha test
substrates. All the agents except polyvinyl acetate could ba applied with a
portable garden-type sprayer. Due to an undesirable foaming that occurred
36
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TABLE A-2. INFLUENCE OF CLIMATIC CONDITIONS ON SURFACE TREATMENT AG£NTS
Agent
Polyvinyl
acetate
surface
collecting
agent
Dispersing
agents
Xanthan
Citrus
pectin
Borate-
silicate
nixture
Sodiua
silicate
cerif leans
Water
Sun
Aids in drying
, film; ->ay aid
in degrading
film
No effect
Unknown
Aids drying
Aids drying
Aids drying
Aids drying
Ho effect
Wind
Adversely affects spray-
ing; generates detri-
ments1, surf action; aid*
dry ing
Adverssl- affects spray-
ing; generates detri-
mental surf action
Adversely affects spray-
ing) generates beneficial
surf action
Adversely affects spray-
ing; generates detri-
mental surf actions aids
drying
Adversely affects spray-
ing i generates detri-
mental surf action; aids
drying
Adversely affacts spray-
ing; generates detri-
mental surf action) aids
dryirg
Adversely affects spray-
ing; generates detri-
mntal surf action; aids
drying
inpr lying and/or drying
Solidifies below 2.2°C
Unknown
High temperature aitis drying; low
temperature may prevent spraying
and/or drying
High temperature aid* drying; low
temperature may prevent spraying
and/or drying
High trirperature »K1n drying; low
teni>erat'jre may prevent sprayirg
and/or drying
Hiqh terrporature aids drying; low
temperature nay prevent spraying
and/or drying
Tidal Action
Hay erode film
.Vust renew troat-
rwnt between
tides
No effect
Film quite soluble,
must he renewed
between ticiei
Filn quite soluble,
rrust. t-*.' rencwc'5
between tid^s
kittle effect
Little effect
Wave Action
Degrrdes filffi
effect
Aids dispersion
action
Dissolves film
Dissolves film
Little effect
Little effect
-------
TABLE A-3. PROBABLE ENVIRONMENTAL IMPACT
Agant
Appearance
Toxicity*
Duration
Polyvinyl acetate
Surface collect-
ing agent
Dispersing agents
Xanthan gum
Citrus pectin
Borate-silicate
mixture
Sodium silicate
Hicrococcus
cerificans
Water
Hard-coated white surface
when wat
None
Clear, gels with water
Clear, gels with water
Glassy coating on rocks
(probably gels with sea
water
Glassy coating on rocks,
gelatinous coating on sand
when sea water added
None
Nona
Nontoxic, air and water perme-
ability unknown
Very low toxicity, care required
in application
Depends on dispersant used
Nontoxic
Nontoxic
Questionable; borates may be
prt.sonous to aquatic flora and
are on list of hazardous sub-
stances, Federal Register, V.39,
August 1974
Silicates on list of hazardous
substances, Federal Reqister,
V.39, August 1974
Probably nontoxic
None
Estimated long duration
One tide
or less
One tide cycle or less
Approximately one tide
cycle
Short duration, less than
1-2 hours in contact with
water
Short duration, less than
1 hour in contact with
water
Short duration, less than
1 hour in contact with
water
Short duration, possibly
1-2 hours
* Toxicity data were taken from published reports and technical information and refer both to organisms on the shore-
line and to people who apply the agent.
-------
when spraying polyvinyl acetate with air-pressure spray equipment, a
oomiercial high-pressure airless spray unit was used.
In seme of the mock-shoreline experiments, the test oil was applied
directly to dry substrates by brushing or spraying. Because oil is
transported to the shoreline on the surface of water/ this practice will not
be continnuad in future testing.
EVAUUA.TION METHODS
Methods used to evaluate the effectiveness of the surface treatment
agents tested include the following:
* visual-subjective judgment (all studies)
* photographic record (all studies)
* analysis of residual oil by measuring oil removed from test bed
(Shell studies)
* analysis of penetration of oil through the agent into porous
substrates (Shell and Tracor)
* measurement of wetting and spreading of oil on treated and untreated
substrates (Tracor)
In addition, scene simple laboratory tests were employed by Tracer to
evaluate other parameters, such as film-forming ability and solubility in oil
and viater, affecting the suitability of film-forming agentj. Most of the
evaluation methods used in the previous studies can be adapted for future
work. Unfortunately, none of the previous studies found suitable methods for
directly determining how much agent remained on a test substrate after
exposure to wave action or how much oil remained on the substrate after
cleanup.
COS!1 O^SICSRATIQNS
Table A-l presents a breakdown of costs associated with the use of each
agent. Ihe costs are estimated for both a 2889-square-meter area and a
50,000-square-fcot area of treated beach. These areas are equivalent to about.
1 tan and 1 mile, respectively, of shoreline that is treated over a
S.l-meter-'wide tidal zone.
Tha costs of agents vary fron 13 cents per kg (6 cents per pound) to over
§220 per Xg ($100 per pound), depending in part on ocmnercial availability.
However, because the quantity needed must also be considered, a more realistic
evaluation of agent cost can bs found in the fourth column, which lists the
cost of agssits needed for either 1 km or 1 mile of shoreline treated. The
effort required to prepares the agent for application is included in the table,
although this is not a factor for most agents since thsy are produced and can
be stored in a usable form. GO!UOTI 7, .Application Cbst, includes labor an?
39
-------
TABLE A-4. ESTIMATED COST
Aqont
rolyvlnyl
«col«t«
Sur/aca
collecting
«g«nt
Dispersing
agents
Xantluin gun
Citrus
pcctir
Borate-
•ilicate
nvixture
Sodium
silicate
Micrococcus
ceritlcans
Water
Material Cote
60«A<) (27«/
Ib) in volu-
tion
52.44/liter;
(59.25/gal),
208.2-liter
<55-gal)
druifls
51.40/Uter
(SS.30/g.ll);
JOB. 2-liter
(55- diumi
S4.50A9
,,2,50/lb!
S7.72Ag
(53.50/lb)
ISC/Kg (6t/
Ib); dry
powder
15C-26 (49 Ib/
mi) - dry weight;
1361.1 kg/km (4900 Ib/
mi) - 11 solution
G'.O kqAro \220 Ib/
mi) - dry weight;
64^9.3 lit«rn/)rn
(2750 qal/rai) in
solution
62.0 kqAm (220 Ib/
mi ) - dry weight;
6468.3 liters/km
(2750 gal/mi) in
solution
42.3 kqAm (150 Ib/
mi) - dry veight
n nown
Material Cost
S754.97A"
(S1,21S/«1)
$574.77Am
(5925/mi)
S77.67/km
(S12V>i)
$J7.29Am
(S60/iTii )
$105.63Am
(S170/B1)
512.43 A*
($20/ru)
515.53Am
(?25/mil
58,077.B3-
$9,320.67Am
(513,000-
S15,000/m.i)
Hone
Preparation At«blo (tr»t for Nil ?• int 1« *rpl 1 ration Unknown
2-yr fttoro'?*.*) $110-$t?l
Stores indef- Nil Multiple applications Nil
initely anticipated, S&21-
5932
Storuo ind«f- Nil Continuous applica- Nil
initely t ions ant-icipatod
(•snail craft, n^ci^s-
rory) , t-:,n;-SlS^1
iiivrw ^iry - Oianolwn flew* M-jltir^ m-1^*- Cnkrown
mixing required 5621-5932
Stores dry - Dissolves slow- Multiple applications Unknown
stable If dry ly, hinh-sh<**r anticipated, *C2l-
nixinrj roquirijd S9i2
Stores dry _ Difficxilt to put Sintle application rnkncwn
into solution 5310-S6XI
Stores dry - Difficult to put Multiple atrplication* UnVnown
hygroscopic into solution antic ir^t^d, T3IO-
C621
Washea off eas- Must Ixs nixed Multiple apnlications Hone
ily. limited stor- with vnter anticipated
a'je except for
spray-dri»?d form
stall at ion inftall, . 5500 C\500
rviintenanr*
" Approximately 2U69 square rnetofs to be treated per km (50,000 square feet per mile).
Labor and equipment for first km (excluding standby).
-------
equipment for the first km of application. Subsequent shoreline coverage
would be considerably less expensive. Excluded from application costs are
standby costs, observation personnel above first-level supervision,
cormtunication systems, elaborate equipment, etc. The cleanup costs are
unknown for most agents because their lifetimes are also unknown. It is
hoped, however, that these costs can be minimized.
Table A-4 shows that agent and application costs are most significant.
The polyvinyl acetate has a moderate to high initial cost., but only one
application is required. The disadvantage of surfactants is that multiple or
possibly continuous applications are required, but film removal is
unnecessary. Xanthan gun and citrus pectin will be somewhat costly to prepare
because it is difficult to form viscous solutions in water and because mixing
equipment is needed. Hicrococcus cerificans has a prohibitive purchase coot
because it is not ccnmonly available, and it requires special laboratory
preparation. Water itself has no cost because it will be drawn from the sea,
but equipment is necessary to provide a continually flowing film. Pipes and
pumps to cover 1.6 km are estimated at $10,000; these are, of course,
reusable.
AlKOTATED BIBLIOGRAPHY
"Shoreline Protection and Restoration fraa Oil Spills," Final Report for API
Ccnmittee on Environmental Affairs, Exxon Research and Engineering Cbnpany,
1974. (Supported in part by EPA.) Evaluation of microbiological agents,
natural plant products, and Biopolymer 9700 for protection of rocky
shorelines.
"Shoreline Protection and Restoration Study," Final Report for API OomuLttce
on Environnental Affairs, Shell Development Company, 1974. Evaluation of
Borax Waterglass and Shell Oil Herder for protection and restoration of sandy
and rocky shorelines.
"Beach Protection Study," Final Report for API Cotmittee on Environmental
Affairs, Tracer, Inc. , 1974. Investigation of sprayable polymeric coatings
for protection of shoreline materials (sand, rocks, wood). A total of 18
agents were screened.
"Microbiological and Natural Product Systems for the Protection and
Restoration of Salt (tersh Grass Iran Oil Spills and Oil Contamination," Final
Report to API Ocnroittee on Enviromsntal Affairs, Exxon Research and
Engineering Ctrcpany, 1974. Evaluation of the effect of treatments with
Bio-polymer 97£&J and citrus pectin on ease of oil cleanup and long-term growth
of salt-marsh grass. ;
"Shell Herder Trials," Ministry of Transport and Waterways, North Sea
Division, Katherlands, 1974. Evaluation of Shell Oil Herder in open-sea oil
spill containment and beach protection and restoration.
J. Nightingale and J. A. Nichols, "Beach Protection: Shell Oil Herder
Chemical," Karren Spring Laboratory, Report LR184(OP), 1973. Assessment of
Shell Oil Harder for protection of shoreline materials from oil vsshed ashore.
41
-------
"Oil Herder," Shell Product Data Sheets. Review of physical properties,
toxicity, biodegradability, and application data.
"Oorcxit 7G64, a Dispersant for Treating Oil Slicks," Exxon Product Data
Sheets. Ravie*' of properties, toxicity, bicdegradability, and appliccition
data.
42
-------
APPENDIX B
PRELIMINARY AGENT EVALUATION TESTS
LABORATORY EVALUATION
Three types of laboratory tests on surface treatment agents vsre
undertaken: (1) screening tests on the basis of solution and film properties
.(solubility, film formation, etc.); (2) small-scale tests of beach protection
on nock beaches; and (3) percolation tests (on three of the agents) for
effectiveness in preventing oil seepage. The tests are described in this
appendix, and the results for each agent are given after the descriptions of
each test. The agents tested are listed below:
* polyvinyl acetate - synthetic film-forming agent (Borden Polyco 694
and 2113 and l&iion Oil Jtosco 3006 and 3011 were tested)
* sodium silicate - inorganic film-forming agent
* borate-silicate mixture - inorganic film-forming agent
* xanthan gum - natural polymeric filnv-forming agent
* citrus pectin - natural polymeric film-forming agent
* dispersing agent - chemical that interacts with oil to form dispersed
oil micelles (Disparsant A was tested)
* surface collecting agent - chemical that reduces oil spreading
* water - continuous film of flowing water
Synergistic effects with the surface collector and tws of the
'film-forming agents, xanthan gun and polyvinyl acetate, were also
investigated.
Laboratory Tests
The film-forming surface treatment agents ware subjected to screening
tests to determine thair solution characteristics, film-forming ability, film
solubility, etc., before their effectiveness on mock beaches vss tested. The
test methods are described below, along with the results for each agent. Not
all agents are listed for each test because not all tests apply to each agent.
Bar instance, Polyco G94 was purchased in a 55% water solution. Hence there
43
-------
is no need to test it for solubility problems. Results will be listed for all
agents for which the test is applicable and are shewn in Table.B-l. Further
testing of the borate-silicate mixture was not attempted because of its
solution instability and failure to produce a detectable film.
Solution Process—
Solutions of desired concentrations were prepared with tap water. The
amount of heating, agitation, and tka required to effect solution were noted
as well a«j special techniques required and the stability of the solution once
formed.
1. Citrus pectin was difficult to dissolve. In order to make a 0.5%
solution (by weight), the solution had to be heated to 50° C.
Heating to near boiling (along with vigorous stirring) was necessary
to effect a 1.0% solution. The solutions are viscous; the 1%
solution has an almost jellylike consistency at rcctn temperature.
2. Xanthan gum was easy to put into solution in both 0.5% cjid 1%
concentratins if cold water was stirred and tne powdered gun added to
the vortex. The solutions became viscous as the powder became
hydrated. Viscosities were approximately the same as with the citrus
pectin.
3. Sodium silicate was impossible to dissolve directly to fern l%-3%
solutions. According to literature on the material, sodium silicate
is more soluble in concentrated solution than in diluted solution.
Thus a 50% ccranercial sodiua-silicate solution was used as a source
of dissolved silicates, and dilutions were nsade tn form 1%, 2%, and
3% solutions. These solutions showed sons cloudiness after standing
for several days.
4. Borate-silicate mixture (sodium silicate/sodiun borate) solutions
were initially made by adding the required weight of borate to the
sqdian-silicate solution. HDMsver, this is not a simple process.
Addition of dry sodium borate to the concentrated sodium silicate
resulted in the formation of a glassy precipitate on the surface of
the silicate which would not dissolve even \£ien heated. (Keating
caused flocculation of undissolved borate but did not affect the
glassy surface.) Solution was effected ly first dissolving the borate
in vater and then adding this solution to a diluted silicate
solution. Using this technique, colvrtions containing equal portions
of silicate and borate salts in the total asotnts of 1.0%, 2.0%, and
3.0% ware prepared. After one day some cloudiness and precipitation
were noted in all silicate solutions. Tha 3.0% solution turned
oonpletsly into a white gelatinous suspension after one day.
Film Formation—
Microscope slides were di£jped two-thirds of thair length into a solution
of the agent and allcwsd to dry- Ifce atpsarance of the film (if any) was
noted and its thickness measured with a ndcrcsTteter.
•44
-------
TABLE B-l. SOLUTION AND FILM PROPERTIES OF SELECTED FILM-FORMING AGENTS
Agent
Concentration
range
Preparation of
solution
Characteristics
of solution
Film formation on
glass slides
Film formation on
screens (dipped)
Properties of films
Sprayability with
conventional
paint sprayer
Citrus Pectin
0.5%-1.0%
Boating required
Viscous to
jellylike
Dipped - very thin
but detectable;
sprayed - fair-
good
Good
Poor-fair
OK
Xanthan Gum
0.5%-1.0%.
Dissolves readily
Jiscous to
jellylike
Dipped - same as
pectin; sprayed -
better than pectin
Good
Good
OK
Sodium Silicate
Undetectable
Difficult (see
text)
Becomes cloudy
after a few days,
pH: 9-11
Dipped - undetect-
able; sprayed -
not tested
No film formed
None formed
OK
Borate-Silicate
Mixture
l%-3%*
Difficult (BOO
text)
3% solution gels
overnight
Dipped - unde-
sprayed -
blotchy, iso-
lated crystal
formation
No film formed
None formed
OK
* 50:50 ratio of sodium silicate to sodium borate, with total concentration in the range of 1% to 3%.
-------
1. Citrus pectin at a 0.5% solution formed a very thin film. Slide
appeared slightly dirty.
2 Xanthan gun at a 0.5% solution did not form a complete film on slide
but seenvad to be thicker than the 0.5% solution of citrus pectin.
The 1.0% solution formed a cloudy, thin film (25 microns).
3. Sodiun silicate and borate silicate - no detectable or observable
film on the microscope slides.
Film Solubility—
The slides from the film-formation test were placed in beakers of salt
water and agitated gently. The appearance of the film was noted as well as
its durability.
Dip-formed films of citrus pectin on glass slides could be readily
removed in 30 minutes by immersion in salt water, especially with slight
agitation. Those films made from xanthan gun yielded films that remained
after overnight inmersion.
'• Since dip-formed films of sodium-silicate and silicate-borate solutions
could not be detected, the imraersion tests on than gave no data.
Screen Film formation and Penetration—
Small squares of fine-mash copper screen ware dipped into each test
solution and allowed to dry* The film that formed (if any) was evaluated as
to appearance and continuity. Continuous films were tested for vater and oil
penetration by simply placing a few drops of water (or oil) on the surface and
checking for its penetration to tha other side.
1. Citrus pectin at a 0.5% solution formed an incomplete film but
covered over 70% of screen. 1.0% - complete film.
2. Xanthan gvra - same as citrus pectin; 1.0$ solution was particularly
good.
3. Sodium silicate and borate silicate ~ no films were formed; agents
crystallized on screen.
Sprayability and Spraysd Film Formation—
Tha test solutions were sprayed onto 10xl0-cm glass plates to test for
spray characteristics. Pressure necessary for spraying, the type of spray
pattern, size of droplets, coverage, etc., were noted.
Citrus pectin, xanthan gun, and borate-silicate films were prepared by
spraying the solutions using a conventional ccn^jressad-air-operated (4.2kg
par sq cm, €3 psi) paint spray gun. All solutions could ba sprayed
effectively. Observations of the films were as follows:
1. The 3.0% borate-silicate solution did not form a corpiate film.
There ware isolated areas of crystals.
46
-------
2. the 1.0% solution of xanthan gun gave a more complete film than that
of the borate-silicate solution. Film was complete in the center of
the glass plate. The coating density decreased as the radial
distance frcxn the center increased.
3. The film of 0.5% solution of xanthan gum was barely observable. It
had the same density vs. radius relation as in tlia solution.
4. The film of 0.5% solution of citrus pectin was ccrnplete but not very
dense. Blotches formed near the perimeter of the plate.
5. The film of 1% solution of citrus pectin was complete. It formed
concentric areas of low-density coverage that were separated by
ridges or barriers of slightly liigher density. Blotches formed at
plate edges.
Film Sol'-Mlity-Durability—
Dry films on the glass plates frcm the sprayability tasts were used. The
slides were propped at a 45-degree angle below a buret filled with salt water.
Water vas dropped from a height of approximately 20 cm onto the film, and its
effect %as noted both at the point of impact and on the runoff area.
1. Borate-silicate 3.0% solution - Water droplets appeared to wash away
any film that may have been present.
2. Citrus-pectin 1.0% solution - The citrus pectin film migrated to tha
lowest edge of the glass plate with the addition of water droplets,
but accumulation at the edge was not as great as with the
accumulation from the 1.0% citrus- pectin solution.
.3. Xanthan-gun 0.5% solution - The xanthan gum film became swollen with
the addition of water but it did not migrate. After drying, the film
was intact.
4. Xanthan-gun 1.0% solution - Parts of the film frcm the 1.0%
xanthan-gun solution migrated slightly toward the edge of ths plate,
but most of it remained intact.
Mock-Beach Tests
Mxk beaches were constructed in approximately 75-cm-square plastic pools
that were mounted in a rocking mechanism. The beach was constructed of sand
and gravel« with some larger rocks and pieces of wood added to the surface.
The total surface area was 0.427 sq meters. Water was added to the pool, and
the rccsing mechanism simulated wave action. The durability of film-forming
agents vas evaluated before any oil was added to the pool. As a result,
several agents were not considered for further testing because they failed tha
durability test. Surfactants were also tested in the nock-beach tests. There
was a control mock beach for each of the mock-beach tests. Detailed results
of the cock-beach tests are given in Table B-2.
47
-------
TABLE B-2. RESULTS OF MOCK BEACH TESTS
Agent Tested
Application Method
Film Durability
Fila Resistance to Oil
Citrus pectin,
1% solution in
water
CitruB pectin,
21 solution in
water
Xanthan gum, 1*
solution in
Xanthan gun
dry powder
Xanthan gum.
dry powder
Xanthan gum,
1* solution in
water
600 ml at 2.8 k>
-------
TABLE B-2 (Continued)
Agent Tested
Application Method
Film Durability
Film Resistance to Oil
Bcrden Polyco
694
Borden Polyco
694
Borden Police
694
Borden Polyco
2113
Union Oil
Ansco 3006
Union Oil
AF.SCO 3011
950 ml of 694 was sprayed on the baach.
This is a heavy coat. The beach wan
dried with the (lid of IR heat lamps
for approximately 20 hours. The film
was still not dry all the way through,
as w»s noted from the characteristic
milky color of undried 694.
<90 ml of 694 sprayed on the beach.
This is a light coat. The film dried
to a clear film after 20 hours under
IR heat lamps.
600 ml of 694 sprayed on the beach.
This is a medium (standard) coat.
Film dried to a clear film in 3.5
hours vith aid of IR heat lamps.
500 ml sprayed on beach and allowed
to dry.
SOO ml sprayed on beach and allowed
to dry with aid of IR heat lamps.
£00 ml sprayed on beach. Dried to a
clear film in 1.5 liours under IR heat
lamps .
Film was slightly hydrated and water became
slightly milky, but the film remained in-
tact for the duration of the test.
Film re.iainc-d intact for the duration of the
test.
Film turned from clear to slightly milky, but
remained Intact for the duration of the test.
After 30 ainutes the film began to dis-
solve. Furthar teats discontinued.
Film dissolved within 30 minutes.
tests discontinued.
Further
Film ra.nained intact. Film did not get the
milky hue that 694 gets when in contact
witn water.
500 irl of »2 fuel oil added.
Oscillations continued for 2 hours.
There was good cleanatility of sur-
face oil; UV Itqht indicated oil
permeation at all depths. Oil
probably penetrated because so
much was applied that It was dif-
ficult to qet the film totally dry.
500 ir.l of »2 fuel oil added. Oscil-
lations continued for £ hours. The
film exhibited good cleanability
characteristics. IP/ light indicated
only slight traces cf oil increas-
ing with the depth. Thic would in-
dicate seepage around the sides of
the film, i.e., at the interface
between the film and the wall of
the j.l, rather ti.a.i jt-cnetration
through the nain body of the film
itself.
500 nl of #: fuel oil added. Oscil-
lations continued for 4 houra. Film
exhibited good cloanobilicy char-
acteristics. Traces of oil were
found just under the film layer at
the Siiiid surface and at a 2.5-cra
depth. Surface traces could have
beun due to pinholes in the film
itself.
Hot tested.
Not tested.
SOO ml of »2 fuel oil added and
oscillations continued for 2 hours.
Film exhibited good cleanability.
Oil trace? were detected at the
sand surface under the film layer.
Penetration into the beach was not
detected.
(continued)
-------
TABLE B-2 (Continued)
Aqent Tasted
Application Method
Film Durability
film Resistance to Oil
in
O
Soc"iuiri-Bi licate
Holution, SO*
Vn water
Sodi ura-s i 1 i cat 9
solution, 6*
in water
Sodium-silicate
solution, l.S\
in vrater
Union Oil
3011 with sur-
face collector
as syner-jist
Xan'han ijun
wit \ surface
collector as
synergist
2» solution
in water
Bispersant A
J0\ solution
in watar
300 ml sprayed on beach. Dried with IR Film dissolved immediately upon water con-
heat lamps to a crusty film.
4no ml sprayed on beach. Dried with
IR heat lamps to a crusty film.
600 nl sprayed on beach. Dried 1.5
hours with IR heat lamps.
600 ml of 3011 sprayed on a mock
beach. Dried under IR heat lairps for
1 hcur. After the oil was added, 20
droi- surfactant/collector applied
at the wash line to see if there were
any syncrqiatic effects from cowbin-
at'on of these ij^ntfi.
150 g of xanthan-gua povder applied,
on wet bQach. 40 drops surfactant/
collector «dded at the wash line
when the oil was added.
100 ml sprayed over the surface of
the nock beach.
100 .nl of this solution was sprayed
over the surfaco of th4 sand.
tact. Further tests discontinued,
j'iln dlstolved immediately upon contact with
water* Further tests discontinued.
Severe erosion within 10 minutes. Further
testa discontinued.
Film remained intact.
Xarithan gum dissolved almost
Not applicable.
Not applicable.
Not tested.
Not tooted.
Not tested.
500 ml of 12 fuel <5il *j.pli«J to
synthetic sea water, oscillation^
continued for 2 hvjrs. After .^; —
plication of surfactant/collector'
a Elight "herdinu" <"iC*-:or. tijo1'.
place. The confining effect of
the h»rder discii atei with timu
dun to the constant c^urnin'i ac*
tio^ of the waves. Oil j>f-noti-ation
tests showed no c!iai.-jt- in iJietce-
tive ability ol the- flln.
SCO ral c: *r fual oil aid..-d.
There was a slj"ht <:oll^ct:n':
action u;«n a.n^licattan of »ha
aurfactant/'-oll»-rtt-:. The co;;-
t'inenent of the oil J-.'.rf-j^'i-i as
tho O'cillation tine incit-n-'-S;
soon rio her'.!in*) effect vir= o\j-
dcnt. UV expo^'irer thowcii litllc
or no surface oil re-.; i-iu'-s, biit
siqrii f .dint rc^id^c.^ ^r derth.^
of 2.5 and 7.15 LT..
500 ml of »2 fuol oil aJdc-.i av.'i
oscillations contir.uevi Cox* 2 hcn.rs.
irv analysis indicate:', oil penetra-
tion at all lev^i':,
too rl t.f «;' fu...J oil aJ-lp'i. I1ii«
oil Wd*5 ertulsi f i<-'.i w[t:i.*n !x rur,-
iit**s. ''V f?x;X5sur<''; i': 'i^T'11.! 01}
jt-r.^t/at icn ot *ilj ]''V'-lu.
-------
TABLE B-2 (Continued)
Agent Tested
Application Method
Film Durability
F'iltn resistance to Oil
Surface collector 20 drops of surface collector were
applied to the oscillating beach
at the wash line
hater {flowing
over the beach
in a continuous
sheet)
Water continuously flowed from «
spray head while excess was simul-
taneously removed.
Wot1 ajjplicable, although there was a consid-
erable asxmnt of beach erosion due to chan-
nels formed by flowing water.
SOU nl cf f~ fin.--1 fii a.i->."! tf, Tho
&i.-a wciVu r f c^ ci J 1 a t;or.» cor *.inuoJ
for T hears. I'V analysis indirated
oil j-iMietraticit at ail levcis.
Oil waa detoctt'.! at all levels.
Tes t r;c thoJ ]- rci^ably doos not sir.-
ulate actual cor.di tic-"5 .
-------
Construction of Mock Beaches—
The same general construction procedures ware used in building all of the
mock beaches. Twenty liters of sand and gravel were added to each
75-cm-square plastic wading pool. 'Ihe beach material was about. .15.2 cm deep
above the wash line and sloped gradually downward toward the other end of the
pool (Figure B-l). The mock beaches were then settled with approximately 7.5
liters of salt solution (3.5% NaCl), which oscillated en the teach for 30
minutes. The excess sea water was then pumped out and, except vtoen a dry
application of xanthan gum was to be tested, seme drying of the beaches was
allowed to occur.
Depending on their physical nature, surface treatment agents were applied
in one of two ways:
* If the agent to be applied was a dry powder, it was sprinkled on the
beach surface through a 200-mesh U. S. standard sieve.
* If the agent was a liquid, it was applied to the beaches as a fine
spray with a Sears Craftsman paint sprayer (700-ml capacity). The
pressure (2.8 to 4.2 kg/sq on, 40 to 60 psi) depended on the
viscosity of the liquid being sprayed. The agents were then dried.
The drying time was frequently accelerated with the aid of infrared
heat lamps.
Test Procedures for Film-Forming Agents—
Tests of film durability and resistance to oil ware used to evaluate the
effectiveness of each surface treatment agent. Ihe film-durability test
determined the ability of the egent to withstand the effects of constant
simulated wave action and sea voter. If an agent did not function effectively
in this test, no further testing of that agent was undertaken.
In the film-durability test, 5.6 liters of synthetic sea water (3.5%
NaCl) was added bo a mock beach on which an agent had been applied. Simulated
wave action was initiated at a constant rate of 10 oscillations per minute for
all tests and was continued for 30 minutes. Evaluation of each agent was
based on the loss of film integrity (developnent of holes, tears, film
dissolving) and on adhesive failure of the film on the beach (formation of
bubbles or wrinkles between sand and film).
The oil-resistance test determiiiad the degree of oil penetration on a
mock beach and the ease with v.hich any surface oil was resnovod. Only agents
passing the film durability test were tested for resistance to oil. In ths
oil-resistance test, 500 ml of oil was added to the water of each bsach, and
wave action was continued at 10 oscillatins per minute for up to 2 hours.
During this time the effects of ths oil on ths agent were observed. After
vave action stopped, the oil/water mixture was drained. The ease with which
the surface oil could be rsnoved fron the bsach was then determined by washing
tha surface with a light stream of water fran a waeh bottle. The panstration
of oil into tha mock beach was determined by taking "blots" of the bsach at
the surface and at various depths within ths beach colirnn. These blots were
taken with Whatman fl filter paper, v.?iich when pressed to tha beach colusn
absorbs a representative saispling of any liquid within the beach column at
52
-------
Motor wrth Variable
Epss:! Trensreiition
x-~^\
15.2 cm
Figure B-.l. Mock-beach design.
-------
that depth. The blots were then examined under short-wavelength ultraviolet
light. Under ultraviolet light, aronatic residues from the oil exhibit a
characteristic fluorescence that can be photographed. The approximate depths
of oil penetration was then determined.
Evaluation of each agent in the oil resistance test was based on the
following criteria:
* If oil remaining on the surface of th& agent could be washed away
with a gentle water stream, the agent was classified as having good
cleanability characteristics for that grade of oil.
* If the oil penetrated the agent throughout the beach (at two or more
depths), the agent was considered unsuccessful.
Test Procedures for Surfactants—
The surface collector was sprayed into .he wash line of an oscillating
mock beach. DLspersant A was sprayed over the surface of the mock beach.
Percolation Tests
The percolation test beach consisted of a circular container that was
fitted with a bottom drain. The container, which was 52.1 on in diameter and
25.4 on deep, was inclined at an angle of approximately 11.5 degrees. Sand
was placed in the test bed so that the surface was also inclined as shown in
Figure &-2. Ihe purpose of this construction was to simulate the seepage of
water through a beach that occurs when a wave recedes from a high-water point.
Testing was therefore done by carefully adding water to the top of the test
bed and allowing the water to drain frcm the bottom.
A sand/gravel mixture was placed in the container to a depth of 15.2 on.
Synthetic sea water was then poured into the container until all the beach was
submerged, allowing the beach material to settle. Water was then drained to a
level below the beach surface. The beach material was replaced for each tost.
The agents tested (Polyco 694, jcanthan gun, and Ttosco 3011) were then
applied to the entire surface of each beach. Dry agents were sprinkled
through a U.S. standard 200-mesh sieve, and solutions were sprayed.
Post-treatment of the films (drying, heating, etc.) was then done, if
necessary. Salt water was carefully introduced into the test beach from the
top so that the film remained intact. Oil (#2, Kuwait, or #6) was then added,
and the water was allowed to drain frcra the bottom, thus seeping through the
beach. Water was introduced two additional tines, allowing the previously
applied oil either to float or to penetrate the film and beach. After three
cycles, the bsach was drained, sectioned, and ex&»tiined for oil penetration at
1-inch intervals. Table B-3 gives the results of the percolation test for the
selected agents.
54
-------
'.n
Surface Arsa S: d.2\ sg. metsr
Figure B-2. Percolation test beach design.
-------
TABLE B-3. PERCOLATION TEST
Agent,
Concentration, Oil Maximum
Volume Application Conditions Added Penetration Comments
Polyco 694
2,346 inl/ni
218 ml
Xanthan gum
516.7 gm/m2
48 gm
Amsco 3011
2,346 ml/m
218 ml
Spray Film
dried
Dry powder Misted
with H20
Spray Film
dried
£2
fuel
#2
Fuel
Kuwait
crude
Surface
under-
coating
Total pene-
tration
Surface
undercoat-
ing
Deep traces, prob-
ably from edge
seepage
Film appeared
intact
Ho oil found at
depth
Other Tests
Tests were conducted on tha mock beaches to determine the most economical
application volume for the Amsco 3011. Beaches were sprayed with 3011 in
volumes equivalent to 300 ml, 500 ml, and 600 ml over a surface area of 0.427
sq m. It was found that a 300-ml film was insufficient for effective
coverage, but 500 ml or roughly 0.11 liter per 0.09 sq m produced an adequate
film. it is important to note that a film of 3011 will not form if the beach
is too wet. It therefore may be necessary in actual field applications to
apply two light coatings of 3011. Both light coatings would dry more quickly
than ono heavy coating.
PRELIMINARY FIELD TESTS - SALT MARSHES
Surface treatment agents selected for the preliminary field tests are
listed below:
1. Synthetic film-forming agent
A. Polyvinyl acetate
2. Natural film-forming agents
A. Xanthan gum
B. Citrus pectin
56
-------
3. Inorganic film-forming agents
A. Sodium silicate
B. Borate-silicate mixture
4. Surface collecting agent
5. Dispersing agents
A. Agent A
B. Agent B
(Dispersant B, a hydrocarbon solvent-based dispersant, was added
to the dispersing agent tests to determine if a hydrocarbon-based
solvent dispersant behaves differently from the water-based
dispersant, Agent A.)
A series of four laboratory tests was performed prior to the preliminary
field tests to obtain qualitative and quantitative data on selected physical
parameters that influence the application of these agents to stalks of cord
grass (Spartina foliosa). Adherence to stalks, drying time, relative
durability, and appearance were exftmned on wst and dry plants.
For the preliminary field tests, an outdoor test tank was constructed and
placed at the preliminary field test site at Cbyote Hills Slough in south San
Francisco Bay. Marsh plots were placed in the tank, coated with each surface
treatment agent, and tested to determine their resistance to contamination
from an oil spill. Arabian crude oil, #2 fuel oil, and 16 fuel oil were used
as the test oils. The effects of wave and tidal action and the ease of
flushing were sane of the parameters evaluated during the test tank
simulation. Ibxic effects of the surface treatment agents on the marsh plots
was examined over a 6-month period.
Laboratory Tteata
Experiment 1: Film-Forming Properties of Film-Forming Agents
on Vfet and Dry Specimens of goartina foliosa—
Wet and dry stalks of Spartina tbliosa were dipped in each of five
film-forming agents - 0.5% and 1% xanthan gum; 0.5% and 1% citrus peccin;
IS, 2%, and 3% borate-silioate mixture; 1.902, 2§, and 3% sodium-silicate and
100% polyvinyl acetate. Six stalk samples, three wst and thr^e iry, were
dipped in each agent at the above concentrations and placed on paper towels to
dry. All samples, with the exception of the polyvinyl acetate, formed
colorless films" that were difficult, if not iitpossible, to detect visually.
Use of a hand microscope did not enhance detection efficiency.
The seanthan-gum samples (0.5% and 1%) exhibited traces of film where the
agent had accumulated, e.g., between the culm and leaves. In sane instances
•the agent had not ootpletely dried overnight. Ifo samples of citrus pectin or
57
-------
sodium silicata produced visually detectable films.
The samples that were treated with the borate-silicate mixture (1% and
2%) showed some milky spots, denoting the presence of a partial film. The 3%
solution revealed crystals on two plants, denoting poor film- forming
capabilities.
The samples treated with polyvinyl acetate were almost completely covered
by a white film. Little difference was noted between the wet and dry samples.
Experiment 2: Film-Forming Capabilities on Wet and Dry
Surfaces of Cellulose Before Drying—
: Shall pieces of Sipartina foliosa cellulose of approximately equal length
and diameter ware dipped in the agents enumerated in Experiment 1 and at the
concentrations indicated. Three wet and three dried culm sections with the
outer sheath removed were used as samples in this experiment for the agents
and concentrations shown in Table B-4. Ifoodamine-B dye was added to each
agsnt before the dip test in order to enhance visual inspection of the film.
The presence of film was evaluated on a yes-no basis only. A film that
appeared continuous or that covered at least 90% of the sample was given a
"yes" response. Table B-4 presents the results of this experiment; xanthan
gum and polyvinyl acetate produced the best films on both wet and dry
surfaces. The 3% sodium silicate exhibited an almost complete film on the dry
Spartina, and the 1% citrus-pectin film was about 90% complete on the wet
Spartina.
Experiment 3: Film-Forming Capabilities on Wet and
Pry Surfaces of Cellulose After Drying—
The agents applied to the culm sectins in Experiment 2 were allowed to
dry for 2 hours. Each culm section was then visually inspected in both
natural and ultraviolet light for the presence of a film. The results of this
experiment are shown in TSble B-5.
In general, the test results showed that the 3% solutions of the
borate-silicate mixture and the sodium silicate formed very light films of
almost 100% coverage on the wet surfaces and somewhat less on the dry
surfaces. The ultraviolet light provided little assistance with these two
agents. The xanthan-gun samples exhibited at least 75% film coverage for both
wet and dry samples, although the wat samples appeared to be covered batter.
The film formed by the citrus pectin was most ccnplete on the wet
surface. The ultraviolet light showed little evidence of film except for soma
areas where the agent had accumulated.
The polyvinyl acetate formed a 100% film on both the wet and dry surface*
from natural light observations, but the black light snowed that the dry
section had a less complete film than the wet.
Experiment 4: Simulated Wave and Tidal Action on Dry Agents—
The culm sections from Experiment 3 that ware. protected by dry agents
subsequently washed with water by a device that simulates wave and tidal
58
-------
TABLE B-4. FILM-FORMING CAPABILITIES OF FILM-FORMING AGENTS ON
DRY AND WET VEGETATIVE SURFACES, BEFORE DRYING
Agent
0;5% Xanthar ^jum
1.0% Xanthan gum
0.5% Citrus pectin
1.0% Citrus pactir
1.0% Sodium silicate
2.0% Sodium silicate
3.0% Sodium silicate
1.0% Borate-silicate mixture
2.0% Borate-silicate mixture
3.0% Borate-silicate mixture
100% Polyvinyl acetate
Dry
Soartina
Yes
Yes
HO
No
No
No
Yes
No
No
No
Yes
Wet
S£artina
Yes J
Yes )
No )
Yes )
No
No >
No
*
No >
/
Wo
'. Yes
Notes
1% solution formed better overall film.
1% solution produced 100% coverage; 0.5%
approximately 90%.
1% solution formed better overall film.
1% solution on wet plants produced approx-
imately 90% film coverage.
3% solution formed best film on both wet
and dry Spartina. Dry Spartina most.
amenable to film covering entire treated
area.
3% solution formed best film on both wet
and dry Spartina. Films quite incomplete -
up to 50% coverage of treated area
Wet Spartina better covered than dry.
Note: Phodaraine-B dye was used to enhance visual inspection.
-------
TABLE B-5. FILM-FORMING CAPABILITIES OF FILM-FORMING AGENTS
ON WET AND DRY VEGETATIVE SURFACES, AFTER DRYING
Agent
Natural Light
Black Light
0.51 Xanthan gum
1.0I Xanthan gum
0.5% Citrus pectin
1% Citrus pectin
1% Sodium silicate
2% Sodium silicate
3% Socliura silicate
1* Borate-silicate
mixture
2% Borate-silicate
mixture
3* Borate-sllicato
mixture
100* Tolyvinyl
acetate
Wet: Licjht film approximately lOOi
complete
Dry: Light film with heavier
blotchus, approximately 75% complete
Wet: Light film, approximately 100\
complete with some heavier concen-
tration
Dry: Heavier film than wet plant;
almost lOOt complete
Wet: Very thin film, about SOt com-
plete if scraped off
Dry: Incomplete film
Wot: Very thin film with some
incomplete areas
Dry: Incomplete film - approxi-
mately 50% coverage
Wet: Very thin film with areas of
no covdrage
Dry: More incomplete than wet,
splotchy appearance
Wet: Very thin film with areas of
no coverage
Dry: More incomplete than wet;
grainy appearance
Wets Very light film, almost 100*
complete
Dry: Less complete film than wet
plan*:; blotchy appearance for both
Wet: Very light film with many areas
not covered at all
Dry: Film less uniform than wet;
poor coverage
Wet: Very light film with patches
of no coverage
Dry: Film less uniform than wet)
poor coverage
Wet: Light film with almost 1001
coverage
Dry: Not a complete film; poor
coverage
Wet: 100% covered by a light film
Dry: 100% covered by a light film
Very difficult to sc-e treated ureas
on both wet and dry plants; somu
areas of heavy concentration
fluoresced well
Heavy accumulations of aqont were
visible, but liyht film, if present,
was difficult to detect
Little evidence of film present;
some bright spots on both wc-t and
dry plants where agent accumulated
Little evidence of film present;
some bright patches on both wet and
dry plants where agent accumulated
Little evidence of film present
Little evidence of film present
Little evidence of film present;
some bright patches
Little evidence of film present;
some bright spots on both wet and
dry plants
Film noticeable but very incomplete
(approximately 50%)» better coverage
on wet than on dry
Light film discernible on both wet
and dry, almost complete on wet;
some bright patches present
Very complete film - visible on wet
plant; dry plant appeared to have
50% to 75% complete film
Note: Ehodomine-B dye used to enhance visual inspection in both natural and ultraviolet light.
60
-------
action. The culm sections were washed for 5 minutes each. Each section was
washed with 250 ml of water every 15 seconds during the 5~minute period. A
schematic of the wave device is sliowm in Figure B-3. The results of this test
are shown in Table B-6.
The xanthan-gum samples showed almost 100% removal of the agent for both
wet and dry surfaces; only in areas where the agent had heavily accumulated
did a residua remain. The citrus pectin appeared to maintain a thin film on
the dried culm sections. The wet culm sections had almost 100% film removal.
The samples of the sodiun-silicate and borate-silicate mixture had almost
100% film removal fron the wet samples, while a slight residue remained on the
dried samples. The 3% agent solutions left a very thin film on both the wet
and dried plants.
The polyvinyl acetate was almost completely renewed from both the wet and
dry samples, although inspection under the ultraviolet light showed that a
very light, continuous film was still visible on both the wet and dry samples.
The ultraviolet light was used only on these samples because it did not
enhance detection of the other agents in previous experiments.
fcesults—
In general, the films formed better on the wet cellulose sections than on
the dry sections. This was observed both before and after the agent dried.
The 3% sodium-silicate solution was something of an anoaaly because it formed
a better film on the dry cellulose sections. The best films overall were
'formed by the xanthan gum (1%) and the polyvinyl acetate. Generally, the
highest concentration of the agent formed the best film. The use of
KhcdsRiine-B dye and ultraviolet light erQianced film detection. The
concentrations of each agent selected for the preliminary field tests were 1%
ixanthan gum, 1% citrus pectin, 3% sodium silicate and 3% borate-silicate
mixture. The polyvinyl acetate was tested only at full strength. Theses
concentrations were chosen on t3ie basis of film-forming ability and durability
under simulated wave and tidal action.
Field Tests
The preliminary field tests were carried out in a tank. Each test slot
separated by a barrier to prevent contamination of individual marsh
sections by the agents applied. A 10-degree slope roughly simulated the slopa
of a salt marsh. A separate holding basin at the end of the tank retained the
oil until a test was ready to be conducted. A wave generator, located in the
rear of the tank, was hand-operated and deliverted 10.2- to 15.2-on waves at
the rate of about 60 per minute.
The basic test procedure for tha citrus-pectin, xanthan-gum,
sodium-silicate, borate-silicate mixture, and polyvinyl-acetate experiments is
outlined below.
* Applying the film-forming agsnts to marsh sections, drying, and
observing the tidal variation and wave action
61
-------
Figure B-3. Laboratory wave device.
-------
TABLE B-6. FILM RETENTION AFTER SIMULATED HAVE AND TIDAL ACTION
of kumoval
0.5t Xantl.an gum
It Xajtthan cjum
0.5^ citrus ttictin
1* Citru8 pectin
11. Sodium silicate
2% Sodium silica..u
3* Sodium silicate
1* Boratu-silicate
mixture
2* Borato-silicate
mixture
3* Borate-silicate
mixture
100V Polyvinyl
acetate
100» Polyvinyl
acetate*
Wot: Almost 100. rciroval of film
Dryt 'Almost 100*. rumov.il of film
Wot: Almost lOO'i removal of film
Dry: Areas whore- film was heaviest still con-
tained some tilm after washing
Wet: 1001 removal estimated
Dry: Heavier concentration workt-d off, but thin
film still remained .
Wet: Almost 10O% removal of film
Dry: Not too discernibly affected by washing
thin film still remained
Wet: Almost lOOt removal of film, althouqh 2 of
the 3 samples did show a slight film remaining
Dry: Fairly uniform loss of almost all the filn
in all 3 samples
Wet: Almost 100% removal of film
Dry: Very light residue noticeable on 2 samples
Wet: Very thin film still partially visible
Dry: Slightly more film remained than on wet
plant surface
Wet: 100* removal estimated; very slight traces
of film
Dry: Almost 1001 reuoval of film, although
slightly more prominent traces than on wet
surface
Heti Very light filn still visible, although
almost completely removed
Dryt Little difference between wet and dry plants
Wet. Very light film still visible
Dryi Somewhat less removal of film than on the
wet sample (averags of the 3 samples)
Wet: Film almost 1001 removed, although slight
film partially visible
Dry: Slightly more film remained than on wet
surface
Wet: Very thin film still visible and appeared
continuous
Dry: Thin film remained and appeared continuous
• Ultraviolet light observation.
63
-------
* Applying the three reference oils to marsh sections without agents
and observing the effects of tidal and wave action
* •Applying the film-forming agents to marsh sections, drying, adding f2
fuel oil, simulating wave action, and flushing
* Applying the film-forming agents to marsh sections, drying, adding #6
fuel oil, simulating wave action, and 'flushing
* Applying the film-forming agents to marsh sections, drying, adding
Arabian.crude oil, simulating wave action* and flushing
Similar tests were conducted for the surfactants. However, a 5-minute
drying time was allowed for the surface collector, while dispersant B and
dispersant A were applied to the plants and to the water directly in front of
the plants as the oil approached.
The tank was filled with approximately 500 gallons of sea water prior to
each testing session. At each testing session, the salinity and water
temperature were recorded, as well as the wind speed, air temperature, and
relative humidity as shown in Tables B-7 through B-10.
Marsh sections of Spartina foliosa were removed frcm a nearby test plot.
Sections were approximately 91.5 on long by 30.5 on wide and were trinraad at
the bottom to a 15.2- to 20.3-cm tiiickness. This depth was judged to be
sufficient to keep the major portion of the rhizomes or root system intact.
Each marsh section was placed on a portable tray and carried to the tank for
testing. Infrared photographs were taken of each marsh section at this point
in order to document the plants in their natural state. Infrared photos were
taken after each test in order to determine the efficacy of the agents in
protecting the plants and the effects of the oil and agents. Eight agents
jwere tested in all, each in conjunction with three different types of oil: $2
fuel oil, $6 fuel oil, and Arabian crude oil. The film-forming agents have
been described previously and were used in concentrations that formed the best
filros in the laboratory testing. Each agent was applied by spraying, although
jthe actual msans varied slightly (see Tables B-ll thrown B-14). Application
•2quipment is discussed in this appendix under Preliminary Field Tests - Beach
Data. The volume and concentration of each agent were recorded and each agent
applied evenly to the marsh plants and substrate. After application, with the
jexception of the surface collector, dispersant fl and dispersant A, the agents
Were allowed to dry for up to 2 hours. , The surface collector was allowed to
dry for 5 minutes, but the dispersants were applied simultaneously to the
marsh section and to the water immediately in fronont of the section as the
oil approached the samples.
After the applied agents had dried, the trays were placed in the
appropriate slot in the tank and submerged until approximately half the
section was under vater to simulate tidal action. This procedure allowed the
oil to contaminate the plants that were partially submerged and those that
remained above the water line but were splashed by waves? it also allowed the
oil to contaminate the substrate during the simulated wavt; action. In the
initial„tests the placement of the marsh sections allowed inspection of the
64
-------
TABLE B-7. WEATHER AT TIME OF AGENT APPLICATION TO CONTROL MARSH PLOTS (no oil used)*
Temperature ( C)
Agent Tested
3% Sodium silicate
1% Xanthan gum
1% Citrus pectin
3% Borate-silicate mixture
100% Polyvinyl acetate
100% Surface collector
100% Dispersant B
2% Dispersant A
Date
12 Jan 77
12 Jan 77
12 Jan 77
12 Jan 77
12 Jan 77
21 Jan 77
21 Jan 77
21 Jan 77
Air
12
12
12
12
12
14
14
14
Water
9
9
9
9
9
11
11
11
Wind
Speed
(km/hr)
8.0
8.0
8.0
8.0
8.0
6.4
6.4
6.4
Drying
Time
(min)
120
105
105
90
75
. —
—
'
'* Salinity - 32 ppt.
-------
TABLE B-8. WEATHER AT TIME OF AG2NT APPLICATION TO MARSH PLOTS CONTAMINATED BY #2 FUEL OIL*
Temperature ( C)
Agent Tested
1% Citrus pectin
3% Borate-silicate
mixture
3% Sodium silicate
1% Xanthan gum
100% Polyvinyl
acetate
Control section
100% Surface
collector
100% Dispersant B
2% .Dispersant A
Date
13 Jan 77
13 Jan 77
13 Jan 77
13 Jan 77
13 Jan 77
13 Jan 77
21 Jan 77
21 Jan 77
21 Jan 77
Air
10.0
10.0
10.0
10.0
10.0
10.0
14
14
14
Water
7
7
7
7
7
7
11
11
11
Wind
Speed
(km/hr)
3-5
3-3
3-5
3-5
3-5
3-5
8.0
8.0
8.0
Humidity
80
80
80
80
80
80
75
75
75
Drying
Time
(min)
90
90
90
--
* Salinity - 32 ppt.
-------
TABLE B-9. WEATHER AT TIME OP AGENT APPLICATION TO MARSH PLOTS CONTAMINATED BY ARABIAN CRUDE OIL*
Temperature ( C)
Agent Tested
3% Sodium silicate
1% Citrus pectin
1% Xanthan gun
3% Borate-silicate
mixture
100% Polyvinyl acetate
Control section
100% Polyvinyl acetate
Control section
2% Dispersant A
100% Dispersant B
1% Xanthan gum
100% Polyvinyl acetate
Control section
100% Surface collector
100% Dispersant B
2% Dispersant A
Date
14 Jan 77
14 Jan 77
14 Jan 77
14 Jan 77
14 Jan 77
14 Jan 77
18 Jan 77
18 Jan 77
19 Jan 77
19 Jan 77
20 Jan 77
20 Jan 77
20 Jan 77
20 Jan 77
20 Jan 77
20 Jan 77
Air
16
16
16
16
16
16
—
—
17
17
17
17
17
14
14
14
Water
9
9
9
9
9
9
—
—
6
6
8
8
8
7
7
7
Wind
Speed
(km/hr)
8.0
8.0
8.0
8.0
8.0
8.0
5.0
—
5.0
5.0
3.0
3.0
3.0
8.0
8.0
3.0
Humidity
75
75
75
75
75
75
85
—
85
85
85
85
85
80
80
«0
Drying
Time
(min)
120
120
—
—
—
* Salinity - 32 ppt.
-------
TABLE B-10. WEATHER AT TIME OF AGENT APPLICATION TO MARSH PLOTS CONTAMINATED BY #6 FUEL OIL*
CO
Temperature ( C)
Agent Tested
1% Xanthan gum
3% Sodium silicate
3% Bora te -silicate
mixture
1% Citrus pectin
100% Poly vinyl
acetate
Control section
100% Surface collector
100% Dispersant B
2% Dispersant A
Date
17 Jan 77
17 Jan 77
17 Jan 77
17 Jan 77
17 Jan 77
17 Jan 77
21 Jan 77
21 Jan 77
21 Jan 77
Air
17
17
17
17
17
. 17
14
14
14
Water
10.0
10.0
10.0
10.0
10.0
10.0
11.0
11.0
11.0
Wind
Speed
(km/hr)
6.4-8.0
6.4-8.0
6.4-8.0
6.4-8.0
6.4-8.0
6.4-8.0
8.0
8.0
8.0
Humidity
70
73
70
70
70
70
75
75
75
Drying
Time
(min)
90
75
—
* Salinity — 32 ppt.
-------
TABLS B-ll. CONTROL MARSH PLOTS TEST DATA
(no oil used)
Aqent Tested
3» Sodium silicate
1% Xanthan gun
1% Citrus pectin
3t Borate-silicate
mixture
1004 Polyvinyl Acetate
Plant Appearance
Thin fi'-m on plant (dry)
but no. .st surface
Hant and surface still
wet
Thin film on plant (dry)
but moiat surface
Thin film on plant (dry)
but moist surface
Film-covered (dry) on
both plant and surface
Volu™
Aqort of Aq^.-.t
Durability (P!) Notes
Tear - no fiin
visible
Cood - jellylika
surface on soil
Poor - no film
visible
Poor - no file
visible
Excellent - good
cover
SOO Wave ac'.ion only (10 min),
garden *i •' '/or on dry plants
1000 Kav« 'Ction only (!•> Pin),
yardcn sprayer on dry plants
" • '- Wave action only HO min),
garden sprayer on dry plants
450 Wave action only (10 Kin),
garden sprayer on dzy plants
i'.'l Kave action only (10 Mini,
spray gur. on dry plants
3V Sodiun silicate
1% Xanthan gum
1% Citrus pectin
It Bozate-silicate
fixture
1001 rolyvinyi acetate
100* Surface collector
100X Dispersant B
21 Dispersant A
Thin film en plant (dry)
but moist surface
Plant and surface still
wet
Thin f'lu! on plant (dry)
but moist sMrfaee
Both plant and surface
still wet
Hot quite as good as
when wet, but still 0
cover
JO
50
500
Tidal action only (15 Bin),
garden sprayer on wet plants
Tidal action only (15 min),
gsrtlen sprayer on vet plants
Tida! action oi.ly (IS min),
garden sprayer on wcf plants
Tid-1 action onl1. (15 Bin),
garden sprayer en wet plants
Tidal action only (15 -in),
spray gun on wet plants
Garden spray
Spray gun
spray
69
-------
TABLE B-12. MARSH PLOTS CONTAMINATED BY #2 FUEL OIL - TEST DATA
Acient Tostod
Plant
Appearance
Substrate
Penetration
by Oil
Aicr.t
Durability
hase of
Flushing Oil
with
Water Spray
Volume
of Agent
(nil
J.'ot^s
It Citrus pectin Oily sheen on
plants
Vury llflc
Pair*
500
/-minute wavo act Jon ,
Ei/raycil on giants a.vi
mixture
Oily sheen on Very little
plants
3* Sodium silicate oily sheen on Very little
plants
Xanthan gum Light oil sheen Very littla
on plants
100* Polyvinyl Light oil sheen Very little
acetate on plants
Control section Heavy oil sheen Very little
100% Surface Light oil shean Very little
collector on plants
100% Diaporsant B Light oil she«n Very little
on plants
2» Dispersant A Light oil shaen Very little
on plants
Good
Fair"
Fair*
Fair*
Excellent Fjir*
Pair*
spr*»yei or. plants ar.J
soil, Tir-^tn opray
450 7-nir.;jle vave action,
BJ.rayed on plants anA
Boil, g^rd«n spray
500 7-nlnu»a wjvo action,
fipi;d on pldrits and
soil, qarc.cn spray
150 7-tninute v.we action,
spraytd on plants and
soil, gar
-------
TABLE B-13. MARSH PLOTS CONTAMINATED BY ARABIAN
CRUDE OIL - TEST DATA
Aqent Tested
•
3* Sodium silicate
It citrus pectin
1* Xantn&n tjun
3t Borate-sllicate
mixture
loot Polyvinyl
acetate
Control section'
2t Dispersant A
loot Dispersant B
It Xanthan gun
1001 Polyvinyl
acetate
Control section
lOOt Surface
col lector
lOOt Dispersant B
2t Oispersant A
Plant
Appearance
Heavy oily layer
on plants and
soil
Heavy oil layer
on plants and
soil
Heavy oil layer
on soil but less
on plants
Very heavy oil
on plants and
soil
A little less
oil on plants
than on control
Heavy oily layer
Heavy oily layer
on soil and
plants
Moderate oil
layer on plants
and soil
Heavy oil layer
on toil but
less on plants
A little less
on plants thn
on control
Heavy oil layer
Little oil on
plants and soil
Some oil on
surface but
little on plant
Little oil on
plants and soil
Substrate
Penetration
by Oil
Very little
Very little
Vtiry little
Very little
Vary little
Very little
Very little
Vejry little
Very little
Very little
Very little
Very little
Very little
Very little
Ksse of
Flushing Oil Volume
Agent with of Aycnt
Durability Water Snii.y (ml)
Poor Fair — similar 500
to control plot
foot Fair - similar 500
to control plot
f-fiftA Ow^ thn -iftl lu-» ^m
uooj
liXe layer helps
the flushing to a
degree
Poor Fair - similar to 500
control plot
Excellent Very good - 150
although some was
fairly clean
Fair - flushing
seemed to remove
over SOt of the oil
Fair - similar 500
to control plot
— — Vcrv flood — the 100
oil seemed to be
exulsilied by the
surfactant
Good Good - the Jelly- 100O
likn layer helps
the flushing to
• a degree
Excellent Very good - 200
although some
was fairly clean
— Pair - flushing
seemed to remove
over SOt of the oil
Very goo<< - oil 30 -So
formed snail
droplets that
were easily washed
off
Very good - oil 75
was emulsified and
easy to remove
by flushi-g
Very good - oil 500
was emulsified
and easy to remove
by flushing
Notes
sprayed on plants ^nd
coil, garden spray
7-rr.inute wave action.
sprayed on plants and
soil, qarclcn cpray
sprayed on plants and
soil, qardcn spray
7-minute wave action.
epraycd on plants ar.d
soil, garden spray
7-minute wave action.
sprayed on plants and
soil, garden spray
7-winute wave action
10 -minute wave action.
sprayed on plantf how-
ever* this method not
recommended j garden
spray
spirayed on plant; how-
ever, this method not
recommended t spray gun
7-minute wave action.
sprayed on plants and
soil, hydraulic spray
7-minute wave action.
sprayed on plants and
soil, hydraulic spray
7-minute wave action
7-ninute wave action.
sprayed on plants and
soil, spray gun
7-minute wave action.
sprayed in front of
'•'1, spray yun
7 -minute wave action.
sprayed in front of
oil, garden sprayer
71
-------
TABLE B-14. KARSH PLOTS CONTAMINATED BY
#6 FUEL OIL - TEST DATA
F-'ose of
Substrate Flushing oil Vulunc
Plant Pr-netr&tion Agent with of A^rjt
Aggnt TPStod Rppearanc* t-y Oil Durability WJter Spray Imlt
1» Xanthai. qum Heavy oil layer Very little Good Fair - oil did 500
on plants and flush i'roA soil
soil
3t Sodium riljcate Heavy oil layer Very little Poor roor - little WO
on plants and to.no oil flushed
soil
3% Porate-sllicste Heavy oil layer Very little Poor Poor - little to 5C?0
mixture rn plants and r.o oil flusi.ej
soil
1* Citrus pectin Heavy oil layer Very little Poor Poor - little to 500
no oil flushed
100\ Polwinyl
acetate
Control section
lOOt Surface
collector
Heavy oil layer Very little
on plants and
soil
Heavy oil layer Very littl«
on pl&nts and
soil
Moderate oil Very little
layer on plants
100% Dispersant B Heavy oil layer Very little
on plants and
soil
2\ Dispersant A Heavy oil layer Very little
on plants and
soil
Excellent Fair - little 200
did flush from
soil
t-oor - littlo to
no oil flushed
Good - oil flushed SO
fairly well from
plants but not as
'well from soil
Poor - little to f5
no oil flushed
Fair - oil diJ 500
not flush from
plant* but a little
did flush from soil
7 min'jtr;s of wave
action, sprayed on
soil and plants,
garden sprayer
7 nit.utcs of vave
action, sj»rayed on
sell And plants,
yardtn sprayer
7 Fiir.utes of wave
action, sprayed on
soil and plants,
garden
7 minutes of wave
action, sprayjd on
soil and plants,
garden sprayer
7 minutes of VMve
action, sprayed on
soil and plants,
garden sprayer
7 minutes of wave
action
7 minutes of wave
action, sprayed on
soil and plants,
qardcn sprayer
7 minutes of wave
action, sprayed in
front of oil, spray
gun
7 minutes of wawe
action, sprayed in
front of oil, spray
gun
72
-------
^relative degree of removal of each agent by tidal and wave action. In besting
the control sections in which the agent was applied without oil, Rhodamine-B
dye end food coloring were used to facilitate the determination of the
relative durability of each agent on cellulose. These results v*>re compared
with the laboratory evaluation results.
For those tests involving oil, a holding basin was used to retain tho oil
behind a movable dam. This allowed the oil to spread quite evenly over the
water surface, subjecting each marsh section to approximately equal volumes of
oil. The volume of oil used in each test varied with the oil being tested.
For the #6 fuel oil test, 6 liters were used; for the Arabian crude oil test,
4 liters; and for the #2 fuel oil test, 2 liters. This difference in volume
was due to the relative viscosity of each oil and its ability to form a
uniform film on the water. At the beginning of each test with oil, the daw
was lifted and the oil "waved" into the vegetation for 5 to 7 minutes with a
wave generator located at the end of the tank. Each wave was approximately
10.2 on high, and the waves were produced at a rate of about 60 per minute.
This frequency and time allowed the oil to move toward and contaminate each
marsh section to the maximum extent possible with the volume of oil used.
Each tray was then pulled out of the tank, and the marsh sections were
observed visually for oil coverage, section appearance, and agent durability.
After the tray was removed from the test tank, each marsh section was
flushed by a low-pressure water spray in order to estimate the ease of
flushing of the oil from the plants and their substrate. Infrared photos were
then taken of each marsh section to provide a comparison with the photos taken
prior to agent application or oil contamination. Oil penetration into the
substrate was checked by ultraviolet light after flushing by removing a
^section of the oiled substrate. The fluorescent properties of the oil could
be distinguished from the fluorescence caused by some of the agents, thereby
determining the penetration of the oil. Since #6 fuel oil does not fluoresce,
no penetration data were directly obtained for this oil, but the viscosity of
the oil is such that actual penetration would be negligible.
After each test the marsh sections were returned to their original plots
and marked for future observation. Oil was removed frcrn the tank by use of
sorbent pads and steam cleaning. Any contaminated oil/water mixture was run
through a separator and embiber beads to remove the last traces of oil.
Uncontaminated water was returned to a nearby slough.
The entire test site was cleaned and policed after all testing was
concluded. All debris vas disposed of in accordance with recomended
procedures.
Results
Unoiled Control Plots—
Surfc.ce treatment agents were sprayed onto both wet and dry SSpartina
•without any oil being used. In both cases, the marsh soil was moist. The
;environmental conditions at the time of agent application and their drying
times are given in Table B-7. A suarary of the control marsh-plot tests is
given in Table B-ll.
'73
-------
After being sprayed on dry plants and over a period of 1 to 2 hours, the
citrus pectin, sodiun silicate, borate-silicate mixture, and polyvinyl acetate
all formed a dry film on the dry plants. The xanthan gum, however, retained a
jellylike consistency on both the plants and substrate. The surface collector
and dispersant B, each having an organic base, formed an oily film on the
plants and soil. Except for polyvinyl acetate, which formed a rubbery crust
on the soil, all agents remained moist on the marsh soil an a result of the
retained moisture in the marsh mud.
Xanthan gun, citrus pectin, sodiun silicate, borate-silicate mixture, and
polyvinyl acetate were tested to determine their durability under simulated
wave action for 10 minutes. After this time no film was visible on the soil
or plants sprayed with citrus pectin, sodiun silicate, or borate-silicate
mixture. A thick film of xanthan gun was still visible on thr marsh soil, but
little was observed on the vegetation in the surf zone. Ralyvinyl acetate,
however, maintained an excellent film on the soil and a very good film on the
plants after the simulated wave action. A week later, polyvinyl acetate
remained on the marsh soil, although approximately 50% had dissolved or eroded
away.
The same concentrations and volunes of sodiun silicate, xanthan gun,
citrus pectin, borate-silicate mixture, and polyvinyl acetate were sprayed on
wet plants to determine their durability under tidal action. Sodiun silicate,
citrus pectinf borate-silicate mixture, and polyvinyl acetate were almost dry
after 1 to 2 hours on the plants. Otherwise, no difference was observed
between the agents sprayed on wet or dry marsh plants.
The agents were then tested under simulated tidal action by being
submersed in sea water for 15 minutes. After this time, no film was visible
for sodiun silicate, citrus pectin, or borate-silicate mixture. The
xanthan-giro film was observed on the soil but not on the plants. Polyvinyl
acetate naintained an excellent film on the soil cover end a very good film on
the march plants.
Plots Tested With *2 Fuel Oil—-
Surface treatment agents were applied to eight marsh plots. An untreated
marsh section was used as a control plot. All of the agents except for the
surface collector, dispersant B, and disperjant A, were allowed to dry for
approximately 1-1/2 hours before being tested. The environmental conditions
at time of agent application and their drying times are shown in Table B-8.
The test results are shown in Table B-12.
The #2 fuel oil was very difficult to observe on the plants. However,
careful observation could detect contaminated plants by a shiny appearance or
sheen on the leaves. A moderate oil sheen was noted on the citrus-pectin,
sodiisn-silicate, borate-silicate mixture, and control marsh sections. Only a
very light oil sheen was observed on the sections sprayed with polyvinyl
acetate, xanthan gun, the surface collector, dispersant B, and dispersant A.
It was very difficult to determine if the sheen on the surface collector or
the dispsrsant B sections was due to the agent or the oil because both agents
are hydrocarbon-based.
74
-------
Citrus pectin, sodiun silicate, arid borate-silicate mixture exhibited
poor durability during this test. Polyvinyl acetate was the most dumble
agent; xanthan gum, the surface collector, dispersant B, and dispersant A had
good durability. The durability of the surface collector, dispersant B, and
dispersant A relates both to the protective layer that remained on the plants
and substrate and to the ability of these agents to break up the oil film
before it reached the marsh section.
Substrate penetration by the oil, determined by using an ultraviolet
light on cores, was found to be slight on all marsh sections, includjjig the
conturol. This may be because this test was conducted shortly after oiling and
the oil did not have a chance to penetrate, or because the substrate itself
acted as an efficient barrier.
The marsh sections were sprayed with a low-pressure water spray to
determine the ease of flushing the oil from the plants and soil. Little, if
any, difference in oil removal was observed between the control section and
the sections protected by citrus pectin, borate-silicate mixture, and sodium
silicate. The sections sprayed with xanthan gum and polyvinyl acetate had
less of a sheen after flushing. This could indicate that the oil was removed
from these sections by flushing or that the oil did not adhere to the
vegetation. The sections protected by Shell Oil Harder caused the oil to form
small droplets, which were easily washed from the plants and substrate by the
water spray. The sections treated with dispersant B and dispersant A were
easily cleaned by water spray. Only slight contamination was still noticeable
after flushing.
Plots Tested With Arabian Crude Oil—
Surface treatment agents were applied to marsh plots. An untreated marsh
section was used as a control plot. Some agents were tested more than once
with Arabian crude oil because they were used for denonstration purposes. All
agents except dispersant B, the surface collector, and dispersant A were
Allowed to dry for up to 2 hours before testing with oil. The environmental
conditions at the time of agent application and their drying times are shown
in Table B-9. The results of this phase are shown in Table B-13.
; ' .'
The test for agent durability was subjective and consisted of visually
observing the agent film before and after wave and tidal action. In most
cases the oil film covered the plant and soil, and deductions were made on the
basis of laboratory experiments. The most persistent agent was the polyvinyl
acetate. Once this agent had cured, it formed a rather solid protective
surface. The xanthan gum was more persistent on the substrate than on the
plants, thereby affording protection against significant oil penetration. The
surface collector, dispersant A, and dispersant B results on agent durability
were somewhat inconclusive because their manner of application differed frcm
the other five agents. Hawever, based on the light oiling observed, it was
assumed that the agents had persisted quite well. It should be noted that for
surfactants, durability relates both to the protective layer that remained on
the plants and substrate and to the ability of these agents to break up the
Oil before it reached the marsh section.
75
-------
Most of the marsh sections were quite heavily oilod upon removal from the
test tank. The oil appeared to adhere to the plants and substrate despite the
presence of the agents, i.e., there was little difference fron the control
section. The exceptions to this were the surface collector, dispersant B, and
dispersant A. Ihe method of application and the nature of the surfactants
kept the oiling of the marsh section to a minimum. There was generally
somewhat less oil on both the vegetation and substrate of the sections treated
with polyvinyl acetate than on the control section.
Ease of flushing was tested using a low-pressure water spray. The
easiest to flush were sections treated with polyvinyl acetate, the surface
collector, dispersant A, and dispersant B. Ihe others were not much different
from the control, although the jellylike consistency of the xanthan gun did
help somewhat in flushing the oil fron the substrate. Oil on the
polyvinyl-acetate-treated sections, especially the substrate, flushed easily;
some oil traces were left on the plants. The surface collector caused
formation of small oil droplets that were easily flushed from the plants and
substrate. In the case of dispersant A and dispersant B, the oil was somewhat
emulsified, which made its removal by flushing quite easy.
. Substrate penetration by oil was determined by cutting a portion of the
oiled substrate away from the marsh section and observing it under ultraviolet
light. Since seme of the agents fluoresce, it was necessary to carefully
distinguish the agent from the oil when looking for oil on the surface and in
the soil column. However, even though different volumes of oil and agent were
observed on the surface of the samples, little or no penetration was observed
in any of the marsh sections, including the control sections.
Plots Tested With #6 Fuel Oil-
Surface treatment agents were applied to eight marsh plots. An untreated
marsh section was used as a control plot. Each agent, except the surface
'collector, dispersant B, and dispersant A, was allowed to dry between 1-1/4
and 2 hours before testing with oil. The environmental conditions at time of
agent application and their drying tiroes are shown in Table B-10. Test
results are shown in Table B-14.
Except for the citrus pectin, sodium silicate, and borate-silicate
mixture, all of the agents showed sane durability during simulated wave
action* Polyvinyl acetate was the most durable agent. Xanthan gun and the
'surface collector vere also good. Dispersant B and dispersant A showed fair
durability. It should be noted that for the surface collector, dispersant B,
and dispersant A, durability relates both to the protective layer that
remained on the plants and substrate and to the ability of these agents to
break up the oil film before it reached the marsh section.
Ml marsh sections, except the section treated with the surface
collector, had a thick layer of #6 fuel oil on the vegetation and substrate
after simulated wave action. The surface collector tended to bead the oil
into thick, round globules; this resulted in less contamination than with the
bther agents.
Little difference was observed between low-pressure water flushing of the
76
-------
control section and citrus pectin, sodiun silicate, borate-silicate mixture,
and dispersant B. Xantlian gun and polyvinyl acetate exhibited somewhat better
results when flushing oil frctn the substrate, and the dispersant A flushed oil
from the plants the most easily. The surface collector seemed superior to all
the other agents in aiding the flushing of oil from the plants. It was also
superior, but to a lesser extent, in aiding flushing of oil from the
substrate.
Substrate penetration by the #6 fuel oil was not observed in any of the
marsh sections tested, including the control. The high viscosity of the oil
prevented penetration from occurring.
Results—
All of the film-forming agents formed a film on the dry cordgrass
(Spartina foliosa), although not all films were complete. The effectiveness
of the fiL-a-forming agents in protecting wet cordgrass and marsh soil from oil
contamination varied significantly. Only xanthan gun and polyvinyl acetate
formed a reasonable, effective, and long-lasting film over the cordgrass and
marsh soil. It was reccnwended that xanthan gun and polyvinyl acetate be
tested during the full-scale field tests to fully evaluate their
effectiveness. The surfactants tested showed promise in preventing
ixwtamination of salt marshes by oil.
Toxicity of Agents to Marsh Plants
Test Procedures—
! Tbxicity tests were performed on 47 plots of cordgrass, (Spartina
foliosa), which were growing adjacent to San Francisco Bay near the mouth of
Coyote Hills Slough in Fremont, California. Each sample was removed fron the
ground with a plug of marsh soil measuring approximately one-third meter in.
Width by one meter in length. A few of the plugs were cut in half to provide
the requisite number of samples frcm the limited amount of test material.
Pare was taken to remove enough soil so that damage to roots and rhizomes was
minimized.
Each plug was set in a specially constructed test tank at an angle to the
horizontal in order to simulate the slope of a marsh surface into an adjacent
body of water. Surface treatment agents and teat oils were applied to each
plot, as surrmarized in Tfcble B-15, and wave action was simulated. The plots
were then replaced in their original locations in the marsh for subsequent
periodic examination. The location of each plot is shown in Figure B-4.
Data Collection—
TVo types of data were collected throughout the sampling period;
* Each plot was qualitatively assessed for relative health and density
of plants.
* Measurements were taken of the height of selected plants in each
plot.
Initially, the turgor and color of the marsh grass provided adequate
77
-------
TABLE B-15. SURFACE TREATMENT AGENTS, TEST OILS, AND MARSH TEST PLOTS*
Dry Dry
Agent Control Control
3% Sodium 1 6
Silicate
1% Xanthan 2 7
gum-
1% Citrus 3 8
pectin
3% Borate-silicate 4 9
mixture
100% Polyvinyl 5 10
acetate
Surface 39
collector
Dispersant B 40
Dispersant A 41
Control
#2 Fuel
Oil
13
14
11
12
15
42
43
44
16
Arabian
Oil
17
19
33
18
20
21
36
32
37
31
38
22
30
35
#6 l-'uel
Oil
24
23
26
25
27
29
34
45
46
47
28
* Entries signify plot numbers; see Figure B-l for location of test plots.
78
-------
Mudflats
N
Water
Mudflats
Water
Figure B-4. Location of marsh test plots.
79
-------
qualitative indicators of health. Healthy plants had resilient, green stems
and leaves, and flaccid, brown stems typified unhealthy or dead plants. Ihe
relative density of the steins was also noted. Saniquantitative records were
kept of each of these characteristics and were sunned to provide an overall
index of the health of each plot.
As time progressed, it became necessary to change the method of
qualitative evaluation. Differences were no longer apparent in color or
turgor of stems and leaves. Stern density remained the single semiquantitative
index of each plot's health.
Height measurements were initiated when it became clear that the new
(1977) growing season was underway. Ten individual plants, distributed along
the central axis of each plot at intervals approximately equal to one-tenth
the length of the plot, were tagged for continued observation. The tags
consisted of grey duct tape attached to one end of a twisted loop of wire that
loosely encircled the stem. Cne untwisted end of the wire was inserted into
the marsh soil. The tags were difficult to maintain during the study period,
and some tags were lost. It was necessary to resample the plants each tiire
height measurements were taken. Records were kept on those plants whose tags
were not lost but were considered insufficient for meaningful data analysis.
In keeping with the objectives of this study, the observations contained
in this report should be considered only as initial indicators of the
potential harm or benefit to be derived from the use of a given iilm-forming
or other agent.
Qualitative Data.—
Relative comparisons of plant reaction (e.g., health) to various
treatments were made on the basis of qualitative observations. These
comparisons are presented in Table B-16. In the first observation period,
Various degrees of plant mortality were observed in seme test plots. These
mortalities are shown in Table B-16 and were incorporated into the relative
comparisons. V£iile by no means conclusive, the distribution of lethal effects
suggests possible agent toxicity in the concentrations used, possible
bil/agent synergistic effects, or ;inccmplete protection by the agent.
Subsequent recovery of most plots where plant mortality was observed further
suggests that the root and rhizcrae masses survived the treatment and that the
"mortality" was only an aerial expression. Ito toxic responses to the
film-forming agents were observed in the agent-treated control plots.
In general, most plots had recovered to approximately normal appearance
by the final sampling period. A notable exception applies to same of the
plots that were contamiiiated with #2 fuel oil. Ihe control plot (no surface
.treatment agent applied) exposed to this oil remained very scantily vegetated
'throughout the sampling period. In contract, the plots that ware very heavily
piled with #6 fuel oil remained in relatively good condition throughout the
sampling psriod. Except for the portions of leaves and stems that were
heavily oil-encrusted, the plants appeared to be healthy. It seems, then,
that the oil that contains the greatest proportion of low-boiling fractions is
most toxic to the marsh grass, whereas the heavier oil's impacts are physical
in nature. (This is consistent with the observations of Jennifer M. Baker,
80
-------
TABLE B-16. RELATIVE CONDITION OF PLANT HEALTH VS. TIME?
QUALITATIVE OBSERVATIONS
10
March 22
April 7-
Kay 11
)'.
3.
4.
S.
6.
1,
8.
1.
2
3.
4.
5.
1.
2.
3.
A.
5.
6.
7.
8.
-J.
1.
2.
3.
4.
S.
G.
7.
8.
9.
1.
2.
3.
4.
5.
6.
7.
8.
y.
Xanthan qua
I'olyvinyl acetate
C'itruf. pectin
J*.M\itu silicate
S-jrfaci! collector
r>isp«rsant fc
Dini.'orsa.it A
Sodium silicate
Boraco silicate
Polyvinyl acetate
Citrus pectin
Xanthan yun
Sodium silicate
Derate silicate
I'o 1 y v i r.y 1 ace t ate
Dispersant B
•Citrus pectin
"Control
Surface collector
Dispersant a
* Xanthan 'jun
Sodium silicate
Control
FOrate silicate
Xanthun qum
I'oly vinyl acetate
Dispcrsant D
*Citrus pectin
Dispersant A'
fEurface collector
Xanthan gum
Citrus pectin
rolyvinyl acetate
Bora to silicate
Dispcrsant D
Sodium silicate
•Surface collector
Dispersant A
^Control
Xanthan qum
Citrus pet-tin
Surf acts collector
Oisporsanc. B
Dispersant A
bo rate silicate
Polyvinyl acetate
Citrus pectin
Sodium silicate
. Xanthan gum
Falyvinyl acetate
Borate silicate
Sodium silicate
Dispereant A
Dispersant B
Surface collector
Polyvinyl acetate
Citrus pectin
Borate silicate
Xanthan gum
Control
r tor ate silicate
Xanthan gum
Sodium silicate
Citrus pectin
Surface collector
Dispcrsart A
Polyvinyl acetate
Control
Pispersant B
Sodium silicate
Citrus pectin
Polyvinyl acetate-
Surface collector
Dispersant B
Xaninan qum
Dispcrsant A
Control^
Borate silicate
Poratc silicate
Surface collector
Xanthan gun
Dispcrsiint A
I'olyvinyl acetate
Citrus pectin
Dispersanf h
Poly vinyl acetate
Sodium silicate
citrus p*;ctin
liorate Silicata
Xanthan qum
Sodium silicate
Pisrcrs*nt A
Surface collector
Xanthan gun
Dispersant B
Citrus pectin
Polyvinyl acetate
Berate silicate
Control
Borate silicate
Podium silicate
Citrus pectin
Xanthan gum
Polyvinyl acetate
Di spcrsent A
Control
Dispersant B
Surface collector
Surface collector
Xanthan qum
Borate silicate
Dispcrsant &
Dispersant A
Con trol
Sodium silicate
Polyvinyl acetate
Citrus pectin
di fference
h'o observable
difference
Sodium silicate
Xanthan gum
C:trus pectin
Pol yviny 1 ace tat«
Surface collector
Di&persant B
Dispersant A
Eorate silicate
Control
No observable
difference
Sodium silicate
Xanthan qum
Citrus pectin
Borate silicate
Polyvinyl acetate
Control
Surface collector
Dispersant D
Dispersant A
x^!thai,s'!,r'jt''
Citrus txjr.-Ljr.
Horat'_ s.iiotr^
I'olyvi n/1 ace i :»:.';.
Surface- conC'-.",'.-r
Disi-crsiinv A
Uisr^rsant !i
Mo oUerva4.lt
dif fercnc*.'
Sodium silicate
Xanthda -jum
Citrus j-cctir.
I'olyvinyl acetate
Surface collector
Dispersant B
Dispoisant A
borate si^ica'.c
Control
Sodium silicate
Xanthan quro
Citrus pectin
Borate silicate
Polyvinyl acetate
Dispcrsant B
Dispersant A
Control
Surface collector
No observable
difference
• The lowest nuirJuer indicates the healthiest plot and the highest number indicates the unhealtliiest p
(i.e., 1 « healthiest plot; 9 » unhealthiest plot).
••No observable difference among bracketed agents.
ff Dead plants observed in t&tit plots.
81
-------
"Comparative Ibxicities of Oils, Oil Enactions and Bnulsifiers," Ecological
Effects of Oil Pollution, ed.E.B. Cowell, London Institute of Petroleun,
1971.) Although not observed during testing, it is suggested that #2 fuel oil
may have penetrated the soil and killed the plants' roots and rhisranes as wall
as stems and leaves. Subsequently, rhizomes from the surrounding soil invaded
the plot, giving rise to the scant vegetation later observed there, the more
viscous #6 fuel oil probably did not penetrate the soil. Consequently,
underground portions of plants exposed to this oil were not affected.
The semiqupntitative indexes described previously provided a means to
suggest airi rank the relative toxic response of each surface treatment agent
for each test oil and control condition. The results are presented in Table
B-16. A few trends are apparent. Note the relative position of the control
plots. In the first observation period (February 10), the data suggest that
most agents were associated with better-tnan-control plant response for the #2
and f& tuel oils, and most produced diminished results with Arabian crude oil.
Over the longer term, the data suggest that most agents are associated with a
better-than-control or an equivalent-to-control recovery. It should be noted,
however, that marsh reaction to various kinds of disturbances (including oil
pollution) is cottnonly manifested by heavy growth and speciation changes.
The increased difficulty over time in distinguishing between different
agent effects is apparent. Sodium silicate appears to be the least toxic
agent, ^ilthough it seems that the surfactants may be toxic, it is difficult
to extract more detailed conclusions frcm the limited data.
Many of the test plots became overgrown with pickleweed (Salicornia
virganica) during the course of investigations. It is possible that this
resulted from sane subtle effect of oil contamination. However, examination
of the surrounding area revealed that pickleweed was probably about to
colonize the test area independently from human activity.
Quantitative Data—
Regression coefficients of height vs.time (i.e.,growth rates) were
calculated for all data points on each plot and for the three smallest stems
within each plot at each sampling period. (Calculations were based on methods
developed by Robert R.Sokal and F. James Rohlf, Biometry, San Francisco:
W.H. Freeman and Company.) Although the latter analysis wao strongly biased
toward young steins, the same bias applies to all plots. Furthermore, it is
reasonable to assume that if long-term stunting occurred, it would be detected
as a shorted minimal stem length in adversely affected plots. Short-term
stunting that affected only stems that were growing when test agents and oils
were applied might remain undetected.
Results of these regression analyses are displayed in Tables B-17 and
B-18, along with the nuribar of times that plants on each plot were measured,
and the statistical significance of the difference of growth coefficients frcm
zero. Statistical significance Jepsnds on the number of samples, the
variation in growth rate among grass stems, and the growth rate of individual
plants. Differences in the number ; of times each plot was sampled are
attributable to tidal inundation of the test area during the first
height-measurement sanrpling and, to .bank erosion that undercut some plots,
82
-------
TABLE B-17. REGRESSION COEFFICIENT - GROWTH RATE (cm/day) USING ALL DATA
3
'
agent
Wet Control
Fuel Oil
Arabian Crude
t
<4-J
1 i
16 Fuel Oil to
3% Sodium (1) .0398 ns 3* (6)
silicate
1» Xanthan (2) .0288 ns 3 (7)
gun
1* Citrus (3) .0129 ns 3 <8)
pectin
3» Borate- (4) .0564 «* 3 (9)
silicate
W mixture
u>
100» Voly- (5) .0573 ns 3 (10)
vinyl
acetate
Surface (39) .0573 ns 3
collector
t
Dispersant B (40) .0366 ns 3
Dispersant A (41) .0546 ns 3
Control
-.0180 ns 3 (13) .0730 . ** 3 (17)
.0411 •* 3 (14) .0971 ns 3 (19)
(33)
.0433 ns 3 (11) .0357 ns 3 (18)
.0056 ns 3 (12) .1137 ns 3 (20)
.0345 ns 3 '15) .0282 ns 3 (21)
(29)
<34)
(42) .0463 ns 2 (35)
(43) .0670 ns 2 (32)
(37)
(44) .0968 ** 3 (31)
(38)
(15) .1242 ns 3 (22)
(30)
(35)
.0643
.0863
.0522
.0748
.C917
.09BO
.0496
.0598
.0284
.0841
.0777
.0032
.1103
.0825
.0309
.0729
ns
ns
ns
ns
ns
ns
ns
ns
***
ns,
ns
ns
***
ns
ns
na
3
'.3
;3
'3
3
3
3
3
3
3
3
3
4
:3
3
3
(24) .0997 ns
(23) .1022 ns
(26) -.0058 ns
(25) .1096 ns
(27) .0478 ns
(45) .0815 ns
(46) .1141 ••
.(47! .0650 ns
(28) .C479 ns
3
3
3
3
4
3
3
3
3
* 10 stems measured at each sample.
1 ** Probability less than .05 that true growth rate is equal to 0.
*** Probability less than .01 that true growth rate is equal to 0.
na • Growth rate is not significantly different fron 0.
-------
TABLET B-18. REGRESSION COEFFICIENT - GROWTH RATE (cm/day)
USING THREE SHORTEST STEMS IN EACH PLOT
s I
•H 'US
Dry Control
Wet Control
'I
#2 Fuel Oil ra
Arabian Crude
0!
'(->
'*6 Fuel Oil
CD
3
.0614 •* 4
.0899 *** 4
.0037 na 4
.P642 ** 4
,0246 ns 4
* 10 stems measured at each sample.
*• Probability less than .05 that true growth rate is equal to 0.
*** Probability less than .01 that true g«-th rate is equal, to 0.
***• Probability less than .001 that true growthirate 1« equal to 0.
na » Growth rata is not significantly different from 0.
-------
causing them to fall to the tidal flats below the marsh. These plots were no
longer growing under equivalent conditions and could therefore not be
considered valid samples.
For most agents and agent/oil combinations, no statistically significant
growth rate coefficients are apparent in the data. However, it is important
to exercise caution in interpreting these data, and the variations suggested
should not be regarded as conclusive. Observed (nonsignificant)_differenceH
may result from factors other than treatment differences, Figure D-5 shows
the location of all plots that displayed a significant growth rate coefficient
in the regression analyses. Some scatter is apparent, but there also seems to
be some clustering toward the shoreline.
In plots that were severely affected by agents and/or oil, many dead
plants (height recorded as 0. on) were initially present. The later samples
included stems that were equivalent in height to many in less severely
affected plots. It is not known whether these steins grew frcra rhizomes
initially present in t)ie soil and stimulated by the testing or from rhizomes
that invaded from adjacent areas of the marsh. Whatever their origin, the
sudden presence of tall stems is reflected in a high calculated growth rate
that may not reflect the true situation.
Further testing using modified techniques will be necessary to
conclusively identify and quantify toxic responses.
PRELIMINARY WIELD TESTS - BEACHES
Preliminary field tests of surface treatment agent effectiveness and
application techniques were conducted in the beat tank previously described.
Most of the beach tests were performed concurrently with tests of agents on
salt marsh. Mavable 0.3-square-meter trays that held simulated beaches made
of sand and of cobble/gravel/sand mixtures were used in ths tank.
The purposes of the preliminary field tests were:
* To gain operational experience in the use of surface treatment agents
* To evaluate the durability of agents on various beach substrates
* To evaluate different agent application .equipment and methods of
relieving the agent
* To determine which agents should be recommended for full-scale -field,
tests
Three series of preliminary field tests were conducted. The purpose of
the first series was to evaluate the durability of the film-forming agent*, and
the ease of flushing of oil from ; these agents on sand and. on
bobble/gravel/sand test beaches, under both wst and dry substrate conditions.
|Itie film-forming agents tested were sodiun silicate, borate-silicate mixture,
citrus pactin, xanthan gum, and polyvinyl acetate. Tide and wave actions were
> simulated in the tank for these tests. In the second series, additional tests
85
-------
Mud f Us
I
Water
Mudflats
Water
~ From analysis of all data
- From analysis using three
smallest stems
Figure B-5. location of plots with growth rates
significantly different from zero.
86
-------
mere conducted with the tvo film-forming agents that proved successful in the
first series, polyvinyl acetate and xanthan gum. In the tests different
application techniques, agent concentrations, and agent drying times ware
evaluated and the two agents' resistance to oil contamination and oil
penetration was assessed. The third test series evaluated four surfactants,
usir*j two application techniques to determine the effectiveness of the
surfactants in ; preventing or reducing oil contamination on test beaches*
Surfactants tested ware the surface collector, dispersant A, dispersant B, and
dispersant C.
Test Procedures
Test Beach Construction—
Test beaches were constructed on 0.3-square-meter trays that slide into
individual cells in the test tank. Tne sand beaches were ccniposed of about 23
kg of counercially available sand about 75 nm deep. Vne ccfcble/gravel/sand
beaches consisted of a 25-mn layer of sand overlaid with a layer of rounded
gravel (less than 25-nrn diameter) and with 10 to 15 cobbles (75-ran to 150-wtn
maximum diameter).
Test Series JL
* Test beaches were constructed for each test.
* The lower half of each beach was sprayed with salt water.
* Borate-fcdlioate mixture, sodium silicate, citrus pectin, and xanthan
gum were premixed (using an electric blender) into water suspensions
at the concentrations recommended by TRI. The agents ware than
applied to r-ach test beach by spraying at 1.75 kg per sq era (25 psi)
with a garda} sprayer (7.6-liter capacity). The polyvinyl acetate
was used undiluted and applied with a point-sprayer/air-corpressor
system at 4.2 kg per sq on (60 psi).
* The agents were allowed to dry for varying, periods of time and then
each beach was submerged under water in the test tank for 10 minutes
to simulate tidal action.
* The test beaches were retracted to a higher position in the tank and
subjected to simulated wave action for 5 minutes.
* The agent on each test bsach was examined to determine the film
durability and integrity.
* No oil was used in test scries 1.
Test Series 2_
* Test beaches ware constructed and prepared for each test as in test
series 1.
* Xanthan gum, when applied dry, was sprinkled by hand on the test
beaches.
37
-------
* A hydraulic spraying system was used for polyvinyl acetate and
xanthan gum solutions.
* After application, each agent was alleged to dry for a given period
of time, and the test beaches were then partially submerged in the
tank. Five hundred mis of Arabian crude oil was added to each test
cell, and simulated wave action was sustained for 5 minutes.
* Jifter the wave action ceased, the test beaches were retracted fron
the water and flushed with a water spray at 1.75 kg per sq on (25
psi) to test the ease of flushing the agent-coated beach.
* A segment of test beach was cut and renewed fron a representative
area and examined under shortwave ultraviolet light to test for oil
penetration. Ihe aromatic content of crude oil exhibits a
characteristic fluorescence which, when detected on the side of the
sample segment, indicates the degree of oil penetration.
Test Series 3^. Surfactants
* Test beaches were constructed and prepared for each test as in test
series 1.
* Two agent application techniques were tried with the surfactants.
- All four agents wers sprayed onto partially submerged test
beaches and into the water in front of the beaches. Five hundred
mla of crude oil was then introduced into each test cell, and
action was sustained for 5 minutes .
- The test beaches were partially submerged in the tank, and
503 or 750 ml of crude oil was placed into each test cell.
- Wave action was initiated and the agent sprayed onto the
foreshore of the beach and into the water in the surf zone in
front of the advancing oil slick.
* Oil penetration into the simulated beaches was determined as
described in test series 2.
Results
Detailed results of the test series on beaches are given in Tables B-19,
B-20, and B-21 and discussed below.
Biefjfective Agents. Three film-forming agents proved ccsnpleteJ.y
ineffective acT surface treatment agents on sand or gravel/cobble/ sand
beaches. These were sodim silicate, borate-silicate mixture, and citrus
pectin. All three agents either dissolved or were mechanically fragmented by
wave action arid/or by suteaergence in water. Further tests of the three agents.
were discontinued.
88
-------
TABLE B-19. SURFACE TREATMENT AGENT BEACH TEST, SERIES 1
m
vo
Tost fluHb«r 1.1
•ilicate
BcacJj Type Sand
Hater tern" 10
Future ( C)
Wind speed 0.0
(si/ see)
Spray 1.75 kg/
(25 psij
Volum? of 50O
A-jent Used (ml)
Percent 1
D i 1 ut ion
Titfw Hequited 60
to Spray
Agent (» (60 psiJ (C3 p-ii:
455 500 20O£> 5OO 3CO ;00
3311 100 100
40 SO 50 SO 1LO 90
1,40 2.25 2.05 2.4* ),4O 1:40
unfl) none ypm; none dry beech dry tection rcrjir,«-i, but . a (nl rcr>ainrj
en beach on beach BOOT vni aectionj en ccbtlfs «f*ii
roraoved fro» Dvcrallj 3ei» tc*t
wet beach re?.alnrd than
Foaa and — tone froth — Difficult Difficult
on Burfaca poored on Bpray^r. s; rayor
during test teach clo-ia^d c to(?'-i<*j
t*ats
-------
TABLE B-20. SURFACE TREATMENT AGENT BEACH TEST, SERIES 2
Test Number
Agent Tested
Beach type
Water tem-
perature ( C)
Air tem-
perature ( C)
Wind apeed
(si/sec)
Percent
Cloud Cover
Applicatic.i
Method and
Spray
rreinuro
Volume of
Agent
Percent
Dilution
Application
Hite
Time Required
to Spray
Agent (sec)
Agent Dry-
ing Tiirj
(hr:ir.in)
2.1
Xanthan
gum (d y
powdei-)
Sand
9
10
1.0
None
Sprinkled
powder on
beach; ap-
plied water
spray
50 g
N.A.
166 g/iq m
120
(dust and
spray)
0:10
2.2
Xanthan
gum (dry
povder )
Cobble/
gravel/sand
9
10
1.0
None
Sprinkled
powder on
beach ; ap-
plied w uer
• pray
50 g
N.A.
166 g/sq n
120
(dust and
spray)
0:10
2.3
Xanthan
gun
Sand
9
10
3.5
None
Hudson
sprayer,
1.75 kg/
ca (25 psi)
1000 ml
N.A.
33 g/sq m
90
2:40
2.4
Xanthan
gum (dry
powder)
Sand
9
10
3.5
None
Sprinkled
powder on
beach; ap-
plied water
• pr«y
100 9
N.A.
333 7/sq m
120
(dust and
spray)
2:30
2.5
Xanthan
gum (dry
powder)
. Cobble/
gravel/sand
9
10
3.5
None
Sprinkled
powder on
beach; ap-.
plied water
spray
100 g
N.A.
333 g/sq m
120
(dust and
spray)
,2:30
2.6
Xanthan
gura
Sand
7
19
1.0
50% hazy
sprayed
agent on
beach with
hydraulic
sprayer,
14 Kg/sq en
(200 pal)
1000 ml
1
33 g/sq n
5
0:30
2.7
Puly vinyl
acetate
(Amsco 3011)
Sand
9
10
1.0
None
Hudson
sprayer,
1.75 kg/sq cm
(25 psi)
400 ml
100
1333 ml/sq m
240
2:30
2.8 2.9 2.10
acetate
(Amsco 3011)
Sand Sand Sand
7 6.5 7
19 18 16
1.0 1.0 1.0
50% hazy None 50% hazy
Sprayed N.A. N.A.
aqent on
beach with
hydraulic
Bprayor,
14 Kg/sq cm
(200 psi)
500 ml N.A. N.A.
100 N.A. N.A.
1666 ifll/sq m N.A. N.A.
15 N.A. N.A.
0:30 N.A. N.A.
(Continued)
-------
TABLE B-20 (Continued)
vo
Test, Nuober
Agent
Tested
Volume and
Typo of oil
Applied (mi)
Percent Oil
Coverage
on Beach
After Test
Depth of
oil Pene-
tration (en)
Results
of Accent
Test
Consents
2.1
Xanthan
gum (dry
powder)
None
N.A.
N.A.
No ditfer-
encc in
jelling on
vet and dry
surfaces;
»o«t of
'agent fiim
broke up in
wave action
-------
TABLE B-21. SURFACE TREATMENT AGENT BEACH TEST, SERIES 3
Test Number
Agent
Tested
' Beach Type
Water Ten-
parature (°c>
Air Ten-
pcrature ( c)
Kind Speed
Cn/sec)
Percent
Cloud Cover
Application
Method and
Spray
Volume of
Agent
Percent
Dilution
Application
a»te
Tine Rcodired
to Spray
Agent (sec}
3.1
Dispersant
C
Sand
6.5
IS
o.a
Clear
Sprayed
agent on
beach with
pr«ssor
spray gun
at 4.2 kg/
sq cm
(60 psi)
560 g
10
186 »l/sq n
90
3.2
Oispersant
B
Sand
6.5
-18
O.8
Cloar
Sprayed
agent on
beach with
pressor
spray gun
at 4.2 kg/
sq cn
(60 pst)
100 g
105
33J ffll/sij m
30
3.3
Dispersant
A
Sand
6.5
13
0,8
Clear
Sprayed
agent on
beach with
pressor
spray gun -
at 4.2 kg/
sg. cn
(60 psi)
500 g
2
33 ml/jq n
24O
3.4
Surface
collector
Sand
10
IB
2.2
eo
Sprayed
agent on
beach and
with Hudson
sprayer at
1.75 kg/
9<3 OB
(25 psi)
40 ad
100
133 al/sq r
10
3.S
Dispersant
B
Sand
10
IS
2,2
80
Spra/ed
agent on
beach and
ahead of
advancing oil
.•'lick with
Hudson spray-
er at 1.75
kQ/aq cm
(25 psi)
75 ml
100
2£0 mi/sa fl
30
3.3
Oispersant
A
Cobble/
gravel/sand
10
1.8
2.2
00
Air compres-
sor and
spray gun
bles at 4.2
kg/sq cm
(60 psi) and
and into
water ahoad
of oil slick
200 ml
2
13 ail/sq m
30
3.7
Dispersant
A
Cobble/
9"vel/sand
B
12
0.5
20
Sprayed
agejit into
water ahead
ing oil
slick with
Hudson
fipray^r at
1.75 kg/
sq cm (25
psi)
SOO ml
2
33 »l/Bc; u
60
3.8
Dispersant
A
Sand
S
12
0.5
;o
Sprayed
aqcnt into
water ahead
ing oil
slick with
Hudson
sprayer at
1.75 kg/
sq on (25
psi)
500 ml
2
33 Ell/sq TT
60
3.9 3.10
Dispersant Control
C baach
Sand Sand with sev-
eral cobbles
8 B
12 i:
0.5 0.5
20 ;a
Sprayed N.A.
37°nt into
water ahead
oil slick vith
Hudson sprayer
at 1.75 kg/
aq en (25 psil
500 ml N.A.
10 N.A.
166 nl/:nj IB W.A.
iO N.A.
-------
TABLE B-21 (Continued)
Test number
Agent
Tested
Percent Oil
Coverage on
Beach After
Teat.
Depth of Oil
Penetration
(cm)
Results of
Agent Test
Commnti
3.1
Dispcrsant
C
30
1.3
Some oi-'
dispersion
on water
however*
oil pene-
trated
beach
Spraying
surfactant
diapersartts
cnto beach
prior to
arrival of
oil is not
effective
in reducing
oil con-
tamination
3.2
Dispersant
B
30
1.3
Oil dis-
persed to
some ex-
water sur-
face; how-
ever, oil
penetrated
beach
..
3.3
Dispcrsant
A
80
1.3-1.9
No oil dis-
persion on
water sur-
oil pene-
tration
similar to
control
beach
„
3.4
Surface
collector
<5
Occasional
spot: 0.6
cm below
surface
Very effec-
tive i only
some oil
splash zone;
tended to
trtve oil
off in
snail
slicks
..
3.5 3.6
Dispersant Dispcrsant
B A
1-10 30
Occasional Some pene-
spots 0,3- tration
0*6 cm below
surface
Excellent Fair effec-
oil dispersed cobbles re-
column; little free; some
remained on oil on sand
beach and gravel
..
3.7
Diapersant
A
60
N.A.
Sand and
lower half
were coated
with a light
covering
«f Oil!
pebbles had
more oil
than rocks
—
3.8 3.9
Disoersart Dispersant
A C
<10 80-100
No pcne- Penetration
tration greater than
control - 3.8
Excellent Not effective;
ness on contamination
was dis-
persed into
water co':':jnn;
very little
on beach
..
3.10
Control
beach
80-100
?,3
Cobbles on
beach coated
with oil
—
NOTES: Water salinity - 32 ppt
Surface conditivn - 100» wet for Test 3,4, 50* w«t and 50% dry for all other tests
Agent drying time - in Test 3.9, 8P 100-WD was allowed to diy for 10 minutes
Volume an'i type of oil applied - 500 ml Arabian crude oil
N.A. - not applicable
-------
Xanthan Gum and Polyvinyl Acetate. Xanthan gum proved fairly effective.
It provided a soft, jellylike barrier film on both sand and gravel/cobble/sand
test beaches and was most effective when applied to dry test beaches in a
premixed 1% solution. It retained film integrity scrnewhat less effectively
when applied to wet surfaces. When xanthan gun was applied as a dry powder
and than sprayed with water, it formed a more rigid film; but the film tended
to break easily under wave action on a sand test beach. On cobble/gravel/sand
test beaches the film formed from dry powder was more successful and did
maintain film integrity. In all cases where film integrity was maintained, a
water spray easily flushed oil from the surface coated by xanthan gim.
When allowed sufficient time to dry, polyvinyl acetate also provided an
effective protective film on both sand and cobble/ gravel/sand test beaches.
The drying time is critical in the use of polyvinyl acetate. On tests where
polyvinyl acetate was still wet, it dissolved into the water column and lost
film integrity. Polyvinyl acetate tended to dry faster on cobble and gravel
than on sand. Where the polyvinyl acetate film integrity was maintained, oil
penetration into the beaches was limited, and oil was easily flushed from the
agent-coated beach surface by a water spray.
The films of both xanthan gum and polyvinyl acetate can be removed from a
sand test beach with a high-pressure water spray, which breaks the film into
snail particles. Itowever, it is considerably more difficult to remove xanthan
gun and palyvinyl acetate films from cobble and gravel surfaces.
Several cobbles coated with xanthan gum and with polyvinyl acetate were
left to cry for. 24 hours. The xanthan gun dried to a firm, nonbrittie crust,
and polyin/1 acetate dried to a hard, paintlike coating. The agent-coated
cobb''-i3 ware subjected to steam cleaning by a portable steam cleaner for 5
minutes v.th no apparent effect on either agent.
Surscace Collecting Agent. Ihe surface collector proved very effective in
reducingoTl contamination of the test beach, although this result was quite
different from those of the tests performed on the collecting agent in the
laboratory. TRI tested it in the concentration reccmmended by the
manufacturer, which is 1 gallon per 2 linear miles of oil slick perimeter, or
approximately 1.2 ml per linear meter of beach. At this concentration the
surface collector proved ineffective. In the tank tests, however, higher
concentrations ware used. The agent was sprayed onto tha test beach and into
the water in front of the beach, where ,it successfully repelled oil from most
'of the beach surface.
Dispersing agents. When they were applied properly, the dispersing
agents. A, B, and C, effectively protected the test beaches fron oil
contamination. When they were used like the film-forming agents and the
collecting agent (i.e., when they were sprayed onto the shoreline before tidal
and wave actions were begun), the dispersing agents were ineffective and in
one case caused more oil penetration than occurred on the control test beach.
When they were sprayed into the water {i.e., surf zone) ahead of the advancing
; oil slick, the dispersing agents effectively prevented contamination of the
94
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sandy test beaches. These agents were scmewhat less effective on
cobble/gravel/cand test beaches; sctne oil contaminated the cobble/gravel/sand
substrate,, but there was considerably less contamination than on the control
beach.
Application Eqaipment. Three types of equipment for applying liquid
agents were evaluated during the preliminary tests. They were:
* Hand-operated garden-type sprayer
* Air compressor (pneumatic) paint spray gun
* Hydraulic sprayer
The hydraulic sprayer was the most effective system for applying the two
film-forming agents, xanthan gum, and polyvinyl acetate. Due to their
viscordty, both agents require high-pressure application to provide an even
coatim in a reasonable amount of time. When the lower pressure garden
sprayer (1.75 kg per sq cm, or 25 psi) and the pneumatic paint sprayer (4.2 kg
per sq cm, or 60 psi) were used to apply these agents, the spray nozzle
clogged frequently, which increased spraying time and made it difficult to
aPPly the agent evenly. However, the lower pressure spraying systems were
effective in applyingrthe surfactants.
95
rVfMNG GUIDE
-------
APPENDIX C
BIOASSAY OF EASTERN BLUE CRAB WITH
SELECTED SURFACE TREATMENT AGEOTS
INTRODUCTION
Two surface treatment agents - polyvinyl acetate (PVA) and xanthan gum -
were selected for the static bioaasay testing (96-hour TIM). First-stage
ijuveniles of the cotmercially important blue crab, Callinectus sapidus, were
used as test organisms. The concentrations tested were in ranges believed to
occur in seawater after an agent film had been removed from the beach and
marsh shorelines.
MATERIALS AND METHODS
Juvenile* blue crabs were furnished by Sea Plantations, Inc., Salem,
Massachusetts Approximately 140 crabs were collected fron the tidal flats of
Delaware Bay on 16 October 1977 and 24 October 1977, packed in seawafcer and
seaweed, and air-shipped to Salem. The crabs were held in aquarium tanks (pH
=7.6, salinity = 32 ppt, temperature =* 21 C) and fed euphausiid shrimp and
small pieces of fish. On 3 Novatiber 1977, the crabs were air-shipped in
plastic bags containing wet seaweeds to Pacific Environmental Labs in San
Francisco. There was no apparent ;stress or mortality of the crabs due to
shirroant.
The crabs were acclimated to test conditions in a 30-gallon plexiglass
aquarium tank for 90 hours. Compartments within the tank kept the larger
crabs separated from the smaller ones. The tank contained filtered Pacific
Ocean seawater (pH = 7.8 and salinity = 30 ppt) from Steinhart Aquarium at
Golden Gate Park in San Francisco. Temperature of the seawater during
acclimation was maintained at 18 +1 C. The crabs were fed brine shrimp during
the acclimation pariod but were not fed during the 96-hour teat period.
* Because of the severe 1976 winter in the east, post-larval (megalops) crabs,
the prescribed test organism, ware 1 to 2 months late. When they finally did
appear in the water column, the msgalops populations were extremely sparse and
difficult to locate. After nutieroiis plankton tows failed to produce any
megalops, and efforts to hatch eggc fron five sponge crabs similarly failed,
Sea Plantations turned thsir efforts in October to obtaining snail juvenile
crabs.
-------
The bioassay test was performed in accordance witi; the method as outlined
in "Standard Methods for the Examination of Water and Waotewater," 14th
Edition, APHA-AWWA-WPCF, and "Guidelines for Performing Static Acute Bioassays
in Municipal and Industrial Wastewaters," 1976, of the California Water
Resources Control Board and Department of Fish and Game.
The tests were performed in seven 19-liter plexiglass aquaria. The
volume of the control and each of the test concentrations were 10 liters. The
control and dilution water used was filtered seawater from Steinhart Aquarium.
The liquid depth of each tank was 12.5 ^3.2 on. Compressed air was used for
aeration.
The test concentrations used were selected (1) to reflect concentrations
that would occur after the agents were flushed frcm the beach and marsh
shorelines, (2) to bracket the lethal and nonlethal toxicity levels of the two
agents, and (3) to make the best use of what turned out to be a small sample
size. Estiniates of agent concentration after flushing were obtained by taking
the application quantities per unit area established during the field tests
and estimating the runoff from this area into a small marsh channel. By
assuming that this receiving water was a closed unit and of minimum volur.e,
worst-case concentrations were estimated (10% for xanthan gum and 5% for
PVA) .* The maximum PVA concentration was estimated at half that for xanthan
gum because PVA tends to adhere better to the plant surface and less was
applied per unit area.
In an attenpt to locate the sublethal toxicity limits for both agents,
the remaining test concentrations were obtained by multiplying tha maximum
concentrations by a factor of 0.3. In this way, a geometric series of
boncentrations, with the lower limits below 1%, were obtained. Test
concentrations by volume of EVA were 5, 1.5, and 0.45%; test concentrations
by volume of xanthan gum were 10, 3, and 0.9%.
So that size differential would not become a confounding variable, 70 of
the snallest blue crabs received from Sea Plantations were selected as the
jbest organisms. These crabs were between 6 millimeters and 32 millimeters in
length (average = 12 millimeters) and approximately 45 to 75 days old. With
only 70 organisms, the tests were limited to three concentrations of each
agent, 10 organisms per tank. One 10-crab tank served ar the control for both
agents. Crabs were placed in the tanks so that each tank contained conparabla
size distributions which, in turn, ; reflected the distribution of the test
population.
* Concentrations referred to in this report reflect the percent by volune of
the teat agents in seawater. The pre-dilution strengths of the agents ware
the same as they were tested in the field: 100% for the PVA and 1% for the
xanthan gisu
97
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RESULTS AND DISCUSSION
Mortality data for the 96-hour TLM are listed in Table C-l and displayed
graphically in Figures C-l and C-2. Goth the PVA and xanthan gun agents were
acutely to.xic to all organisms in the highest concentration tanks. The PVA
seemingly affected the crabs more quickly than did the xanthan guni. Though
only two of the crabs in 10% xanthan gum were dead after 24 hours, six others
were moving very slowly by that time. By 48 hours, all 10 crabs in the 10%
xanthan gum had died.
Kfo mortality occurred in the tanks subjected to the lowest concentrations
of each agent. The intermediate PVA concentration (1.5%) was not as
immediately toxic to the crabs as was the 5% concentration, but four crabs
died between the 48- and 72-hour reading ?.nd another four died by the end of
the test. The 10 crabs subjected to the intermediate xanthan gun
concentration all survived. All 10 of the control crabs survived, btone of
the surviving crabs in the test showed any signs of paralysis or stress.
Although the sizes of the crabs varied between 6 nm and 32 inn, there was no
apparent correlation between the size and mortality of the test animals used.
During the test, two of the blue crabs molted (one each in 3% and 0.9%
xanthan gum concentrations). Both of these molted blue crabs survived the
96-hour test period with no apparent paralysis or stress.
Water quality data taken during the tests (Table C-2) suggest that a low
pH might have contributed to FVA's rapid and acute toxicity. Figure C-3 shows
:that as the concentration of FVA increased, initial pH and alkalinity (a
measure of the solution's buffering capacity) decreased. In the 5% PVA tank,
the pH decreased to 4.2 and remained at that level for at least 48 hours.
iVJhile the pH decreased to 5.9 in tha 1.5% tank, within 24 hours the pH had
Iclimbed back to more than 7 with no apparent effect on mortality.
Dissolved oxygen levels fluctuated considerably throughout the tests
(Figures C-4 and C-5). At all three concentrations of xanthan gun, the oxygen
TABLE C-3. STATIC ACUTE BIOASSAY MORTALITY (%)
Control
Initial
0
24 Hours
0
48 Hours
0
72 Hours
0
96 Hours
0
PVA
.0%
.5%
0.45%
Xanthan gum 10.0%
3.0%
0.9%
0
0
0
0
0
0
80
0
0
20
0
0
100
0
0
100
0
0
100
40
0
100
0
0
100
80
0
100
0
0
98
-------
9 -
8 -
Number of 7
Test Animals
Dead
6 -
10%
1.5Z
0.45*1
Initial
Figure C-l. Static acute bioassay mortality — polyvinyl acetate.
: 99
-------
10
Kumber of
Test Aclmals
Dead
Initial 24
/•a
Hours
72
10%
3Z& 0.9*
96
Figure C-2. Static acute bioassay mortality — xanthan gum.
100
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TABLE C-2. ALKALINITY, pH, AND DISSOLVED OXYGEN DURING THE 96-HOUR TLM
Initial
Control
PVA
Xanthan
gum
5.0%
1.5%
0.45%
10.0%
3.0%
0.9%
Alk.
144
1.0
89
126
146
146
146
pH
8.0
4.2
5.9
6.9
8.0
8.1
8.1
D.O. Alk.
8.6
8.3
8.5
8. 6
8.4
8.5
8.6
24 Kours
pH
7.9
4.2
7.2
7.4
7.1
7.6
7.8
D.O.
8.1
8.9
8.3
2,6
3.0
6.2
7.4
48 Hours
Alk. pH
7.8
4.3
7.2
7.8
7.7
7.7
7.9
D.O. Alk.
3.0
8.6
3.4
8.0
7.8
7.6
8.4
72 Hours
pH D.O.
7.8 8.0
_-
7.2 2.6
7.9 9.2
7.8 7.6
7.9 8.2
96 Hours
Alk. pH D.O.
7.7 7.7
7.5 4.5
7.9 8.0
7.7 7.0
7.9 7.R
-------
pH
\
\
\
\
\
\
\
\
\
\
\
\ Alkalinity
X
N
\
\
160
.120
80 Alkalinity
mg/1
40
23
Z Concentration
Figure C-3. Effect of different concentrations of PVA
on alkalinity and pH in the test tanks.
102
-------
Dissolved
Oxygen
mg/1
Initial 24
48
Hours
72
0.9%
Control
96
Figure C-4. Dissolved oxygon fluctuations — xanthan gum.
103
-------
Dissolved
Oxygea
mg/1
Initial 24
48
Hours
72
0.45%
Control
1.5%
96
Figure C-5. Dissolved oxygen fluctuations — polyvinyl acetate.
104
-------
level decreased during the first 24 hours of the test before returning to
control levels. The dissolved oxygen in the 10% tank dropped to 3.0
milligrams per liter, possibly contributing to the narcosis observed in six of
the surviving eight crabs in that tank. Oxygen sags, however, were not
necessarily associated with mortality. The oxygen level in the 0.45% PVA tank
dropped to 2.6 milligrams per liter during the first 24 hours with no adverse
effects. Thus, wliile it is possible that the loss of dissolved oxygen
contributes to the mortality of the crabs, especially when the crabs are under
stress due to the presence of high concentrations of the agent, data frctn this
bioassay are not extensive enough to implicate oxygen sags as a factor in the
toxicity.
Ihe TLMs for the two agents were estimated graphically (Figure C-6). In
this case, the TLM is an integrated value approximating the concentration at
which 50% of the experimental animals survived. The 96-hour TTM for PVA was
0.95%; the 48-hour TLM for PVA was 2.3%. Both the 48- and 96-hour TLMs for
xanthan gun were 5.5%.
Ihese TIM values, and particularly those for the high concentrations of
the agents,* probably reflect the crab's response to conditions worse than
would occur in the natural environment. Whereas the initial concentrations
Delected probably are realistic estimates of their potential strength in the
natural environment, the chances of these concentrations persisting for 96
hours are extremely low. Tidal flushing of the beach and marsh shoreline
would effectively dilute the agent concentrations. Thus, the 24-hour and
48-hour TLMs are more likely to reflect the worst-case conditions that the
crabs would encounter. Similarly, the crabs in the natural environment could
move out of and/or avoid any pockets of high agent concentrations. .Additional
testing with concentrations intermediate to those used in this test would more
precisely define the TLMs for these agents, and would produce additional
information on 24- and 48-hour toxicity.
The results of the bioassay apply only to the acute effects of these
Agents and do not provide any information about the effects of long-term,
chronic exposure. The toxicity data generated also do not apply to any other
marine organisms, or even to other Callinectes of different size, age,
location, or physiological condition. Similarly, the data do riot provide
information about possible synergistic and antagonistic effects. Oil and
oil/agent bioassays vould provide va-.uable information in this regard.
<* Researchers observing the bioassay who hM worked with the agents comvsnted
that the lowest PVA concentration (0.45%) was most similar in appearance (like
(skimmed milk) to the PVA/water mixture that occurred in the field during
flushing. In contra?t, the 5% PVA tank had a thick and milky appearance.
Jmnediately after the introduction of the xanthan gum agent into the 10% tank,
the water thickened to a consistency more like the agent than water.
105
-------
10
5.5
5.0
Z Concentration
3.0
2.8
1.5
0.95
0.45
0.1
10 30 50 70
% Survival
1 1 1 L
90
Xan.ch.an Gun
48 & 95 - hour
PVA 48 - hour
PVA 96 - hour
Figure C-6. Estimations of 50% tolerance limits by
straight-line graphical interpolation.
106
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FINDINGS AND REXXMMEHCIAT1ONS
1. The acute static bioassay successfully established 96-hour toxicity
ranges for the two agents: FVA (0.45% to 3%) and xanthan gin (3% to
10%).
2. PVA (as applied at 100S) is seemingly more toxic to first-stage
juvenile Callinectes than is xanthan gum (as applied at 1%).
3. The PVA at 0.45% concentration did not have any apparent
physiological effect on the crabs during the 96-hour test period.
4. The xanthan gum at 3% concentration did not have any apparent
physiological effect on the crabs during the 96-hour test period.
5. The 96-hour TIM for EVA was 0.95%.
6. The 96-hour T£M for xanthan gun was 5.5%.
7. The PVA seemed to act like a weak acid. The persistent low pH level.
in the 5% tank could have contributed to the toxicity of the agent.
Additional tests on the chemical behavior of PVA. in water are
recommended.
8. Acute bioassay tests with first-stage blue crab juveniles using five
or six concentrations in the ranges delineated in (1) above should be
performed. Additional testing with post-larval crabs, generally
regarded to be more sensitive than first-stage juvenile, is also
recarroended.
9. Organism toxicity of oil and oil plus agents should be determined
through additional bioassay work.
107
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APPENDIX D
SURFACE TREATMENT AGENT TESTS - SIEDLER BEACH,
NEW JERSEY, OCTOBER 18 AND 21, 1978
INTRODUCTION
Since 1976 Woodward-Clyde Consultants has been conducting a research
program to evaluate the effectiveness of various natural and chemical agents
in protecting shorelines from oil contamination. This program is jointly
funded by research grants from the Environmental Protection Agency and the
American Petroleum Institute.
As a continuation of this program, field tests of several surface
protection agents ware held at Seidler Beach, New Jersey, on October 18 and
21, 1978.
SCOPE
The field test program was originally planned to evaluate the
jeffectiveness of the following four agents and a flowing film of water in
protecting shorelines from oil contamination:
* Oil Herder, a surface collecting agent
* Corexit 7664, a dispersant
* BP 110SK, a disparsant
* Polyvinyl Alcohol/Borate-Gel, a film-forming chemical
Initially, the tests were to be conducted in the following manner. On
four -test areas the surface collecting agent, the BP 1100X dispersant, and
Corexit 7664 undiluted ware to be applied onto the water surface in front of
an oil slick being carried
-------
In the revised test program the water spray system, the polyvinyl
alcohol/horate-gel, and the educted Corexit 7864 v-Tere applied to the shoreline
as planned. Based on reccrtmendations of the manufacturers' representatives,
Oil Herder and BP 1102K were not tested. Undiluted Cbrexit 7664 was sprayed
on the shoreline test area rather than applied to the water surface. In the
three tests conducted, oil was physically forced onshore with containment
boons.
CONCLUSIONS
Based on the results of the October 1978 test program, the following
conclusions are offered:
1. The flowing water film produced by the water spray system was most
effective and provided the best protection from surface oil
contamination and oil penetration into the substrate.
2. Palyvinyl alcohol/bora te-gel did not reduce surface oil
contamination. However, it did prevent oil from penetrating the
substrate and appeared to facilitate removal of oil by flushing. As
a surface barrier, the gel remained on the beach for only one tidal
cycle.
3. The tests of Cbrexit 7664 as a protection agent were inconclusive.
Visual observations indicated that although Cbrexit 7664 applied to
the shoreline prior to oil contact did not reduce the initial amount
of surface oil contsmination, it appeared to facilitate the removal
of oil. The use of Cbrexit 7664 did not reduce the bearing capacity
of the test areas, i.e., make it quicksand.
Based on the findings of this study the following recommendations are
Offered:
* Additional field tests to evaluate Cbrexit 7664 and the other
products (BP 1100X and Oil Herder) should be conducted when the oil
is moved ashore by onshore winds and currents.
* In future testing a larger sediment sampling program will be needed
to provide ctatistically significant samples..
* Sediment samples should be taken from the test plots for several days
after a test to determine if the agents facilitate the natural
cleaning of a shoreline by t.''.dal action.
* Ebr sand/gravel application, external flushing should be avoided.
Any ensuing test program should be designed to evaluate several
periods of natural tidal flushing.
109
-------
* Tho logistics and operational procedures for deploying and using a
water spray system on a large scale should be investigated.
FIELD TESTS
Test Site
Field tests were conducted at Seidler Beach, located on the New uersey
coastline of Raritan Bay between Laurence Harbor and Cliftwood Beach (latitude
4cP 27' 20", longitude 74° 14'). The beach is situated in the west corner of
Raritan Bay, just southeast of the c..—mergence of the Arthur Kill and Raritan
River, and is bordered by the outfall of Marquis Creek to the northwest, a
sewage treatment plant to the north, and Raritan Bay Beach to the southwest.
Seidler Beach is approximately 1600 feet long and is owned by the Township of
Old Bridge. The shoreline is primarily ccmposed of coarse sand in the upper
intertidal zone with large pebbles dominating the lower intertidal zone.
Access to the beach is through an undeveloped 60-acre lot fronting Highway 35.
Test Oil
A light Iranian crude oil with similar characteristics to test oils
previously used was selected as the repr ssentative oil for the testing of
shoreline protection agents. Characteristics for thits oil are given in Table
D-l.
Dontrolleg Spilling of Oil
Approximately 170 to 190 liters (45 to 50 gallono) of Iranian crude oil
were spilled for each daily agent test. These volumes would provide a uniform
oil loading of approximately 2 to 4 liters/ mater of sloreline, or about 50 to
75 liters of oil for each individual test area.
During each test the oil was spilled within the containment boons on a
flooding tide just prior to high tide. The boons were then pulled up onto the
beach, drawing -Jhe oil onto the test areas.
TABLE D-l. CHARACTERISTICS OF IRANIAN CRUDE
Characteristic Value
Gravity 35.5 °API
Viscosity
Kinematic 6.4 CS at
Pour Point -20°F
110
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ent Evaluation Procedures
Three surface protection agents were evaluated during the test progrc-on.
Ihese were tested on the following days:
10/18/78 Polyvinyl Alcohol/ Film-forming agent
Borate Gel
Water Spray Flowing water film
10/21/78 Corexit 7664 Water-based dispersant
Film-Forming Agent and Water Spray
Two 25-meter-long test plots (one for the control and one for the
fVA/borate-gel) and one 10-meter-long test plot (for the water spray) were
laid out along the upper intertidal aroa at the southern end of Seidler Beach.
Each test plot was separated by booms that were set in the beach sediments,
extending into the water perpendicular to the beach (see Figure D-l).
The water spray system was constructed of a 10-meter section of
5-centimeter (2-inch) diameter PVC pipe with 1.27 centimeters (0.5 inch) flat
fan jet spray nozzles fitted on 1.8-meter (6-foot) centers connected to a
;378-liter/minute (100-gpm) centrifugal pump. The pump drew seawater from a
suction line placed approximately 3 meters offshore. The spray pipe was
placed on supports approximately 0.5 meter high along the upper intertidal
area, with the spray nozzles oriented to give a flat spray angled downward,
jtoward the water. This orientation provided an even flowing film of water
over the beach sediments.
The polyvinyl alcohol/borate-gel was applied in two parts using two
Separate spray systems over a 25- by 3-meter area in the upper intertidal
zone. A premixed 5% solution of polyvinyl alcohol was sprayed across the test
area using a gear pump and hose. Cnce the polyvinyl alcohol solution was
'applied, it was sprayed with a saturated borax solution, causing it to gel in
jplace. Concentration and application rates of the film-forming chemicals used
were:
Concentration application
HV-Polyvinyl Alcohol 50 grams/liter 600 ml/m2 (30 g/m2)
fcorax (sodium tetraborabe 25 grams/liter 30 ml/m2 (0.75 g/m2)
decahydrate)
Corexit 7664 ^ Dispursant
One 25-meter-long control plot and two 12.5-meter-long test plots were
laid out long the upper intertidal area of the northern part of Seidler Beach
(Figure D-li). One 12.5-meter test plot was sprayed with 5 liters of Cbrexit
7664 eductad in a 2% solution through a fire hose. The other 12.5-reater test
plot was sprayed with 5 liters of. Oorexit 7664 applied neat (undiluted) with a
111
-------
Figure D-l. Film-forming agent test configuration.
112
-------
Secondary booms
Spilled oil
Spilled oil
Figure D-2. Dispersant test configuration.
-------
backpack sprayer.
Test Procedure and Data Collection
All of the agent evaluation tests ware conducted in a similar manner.
The test procedure was:
1. Spill oil inside of boans for each test and control area.
2. Apply agent onto test areas.
3. Bring oil onto shoreline usi^j containment oocrcs, create waves on the
shoreline using the wake of a small workboat driven parallel to the
beach.
4. Approximately 45 minutes after oil is brought ashore, test and
control areas are flushed with seawater using a fire hose and 100 gpn
fire pump. (The water spray test area was not flushed after the
shoreline was contaminated.) Flushing is conducted to determine if
the agents prevent the oil frcm adhering to the sediment.
Table D-2 summarizes the test conditions and procedures. Data on the
effectiveness of each surface protection agent was obtained visually and by
taking sediment samples which were analyzed for oil content.
The sediment sampling program involved taking two surface samples and two
subsurface samples (at a depth of . 10 to 15 centimeters) in each test and
bontrol area, at two different times: !(1) after oil came ashore, and (2)
after each test and control plot was flushed (Figure D-3 shows sample
locations). Samples were also taken in the lower intertidal area several
Jours after flushing when the receding tide had exposed the tide flats.
jSeveral background samples were taken on the test beach and on the control
beach prior to the tests.
Obne pentrcflteter readings were taken on the dispersant test sites before
and after the teats to determine if the use of tlispersants on a shoreline
altered the bearing strength (and the trafficability) of the beach.
A detailed description of the sediment sampling procedure is contained in
Appendix D-l.
Biological Testing Program
A biological sampling and analysis program was conducted in conjunction
with the dispersant tests. A description of this program and the results
obtained is contained in Appendix D-2.
i
Taat Results
l.
General—
; In all the tests, oil contamination of tha substrata was very uneven.
Because of the sporadic nature of tha oil contamination tha number of
114
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TABLE D-2. SUMMARY OF TEST CONDITIONS - TEST AGENT
Test Condition
Time of agent
application
Amount of
agent used
Aniount of oil
spilled
Time of oil
spill
Length and
width of test
area (meters)
Wind direction
Kind Speed
Polyvinyl
Alcohol Borate
10/16/73
Start 9:10
Stop 9:15
2250 grams - PVA
(45 liters - 5% soln)
50 grains - Borate
57 liters
9:03
9:04
25 x 3
Control tl
10/18/78
_
-
57 liters
Start 9s 00
Stop 9:01
25 x 5
Ea?t
0-10 roph — — —
Water Flush
10/18/78
N/A
378 liters/
minute
57 liters
9:06
9:07
10 x 3
Cosrexit 76G4
Control #2 Neat
10/21/78 10/21/78
Start 11:17
Stop 11:25
5 liters
95 liters
Start 11:08
Stop 11:10
25 x 5 12.5 x 5
East
Corexit 7664
Kducted
10/21/78
11:26
11:31
5 liters educted
at 2%
95 liters for
both plots
Start 11:14
Stop 11:16
12.5 x 5
-------
LEGEriD
Upper intertida! series of samples
Lower intertidai series of samples
fi
Lower
intertidai
Clam cages
n n© ©
© © ©
12.5 12.5
m m
Clam cages
DD
3- 25m -w-25 m—di
m—t|3-25m-«H—KJ—«—25m-» H-25m-J»-25m-iifc-25m-5J«-25m-sJ3— 25m-? 4— 2
5m-; >3— 25m HS>
Figure D-J. Sample location map.
-------
substrate samples collected were insufficient to provide statistically
significant results. In order to provide statistically significant data, the
number of samples collected and analyzed would have had to have been increased
by an order of magnitude which was beyond the funding limitations of the
program. Therefore, care must be taken when interpreting or using the data
presented in this report.
Although the test area appeared to be free of oil contamination prior to
the tests, background (baseline) samples of the test beach and a control beach
a mile away indicated background oil contimination levels in the substrate
ranging from 8 to 39 rag/kg (ppn).
Polyvinyl Alcohol/Borate-Gel and Water Spray System—
The results of the polyvinyl alcohol/borate-gel and the water spray
system are shown in Table I>3. The polyvinyl alcohol/borate-gel film did not
prevent the substrate from becoming contaminated; however, it. appeared to
prevent oil from adhering to the shoreline sediment as both the visual
observations and sediment sample results indicate. The film prevented oil
from penetrating the substrate. A preliminary test application of the film
suggested its persistence to be less than one or tvo tidal cycles. The water
spray system proved to be quite effective, prevnting oil from contaminating
the test zone by countercurrent flow of water over the beach.
Both the polyvinyl alcohoborate-gel and the water spray system appeared
to prevent oil from penetrating the beach sijbstrate. However, the beach is
composed of firm sand and gravel and oil penetration of the control area was
also minimal.
Gorexit 7664—
The results of the educted and neat applications of Cbrexit 7664 are
shown in Table 1>4. The disparity in sane of the replicate samples of one to
two orders of magnitude make the results very difficult to interpret.
Educting ths same volume of dispersant onto the beach was faster and appeared
to give more even coverage than applying the dispersant neat. Visual
observations indicated that oil deposition on the dispersant-treated plots was
only marginally less than on the control plot, with the least amount of oil
present on the tiest plot where Oorexit 7664 was educted in a 2% solution.
Visual observations of the test and control plots after they were flushed
with ssawater indicated that the disparsant-treated plots were more easily
cleaned.
The sediment samples analyses indicate that there was more oil on the
test and control plots after flushing than before flushing. This was not
confirmed by visual observations and is an example of sampling error.
This use of dispersants did not appear to cause oil to deeply penetrate
'the sediments. The samples and visual observation taken at a depth of 10
centinietors indicate very little oil contamination of either the control plot
or the dispsrsant-treated plots. However, after the test and control plots
were flushed, a diffused sporadic band of oil was observed 3 to 5 centimeters
below the surface in all three test plots, apparently.related to ths flushing
operation.
117
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TABLE D-3. SAMPLE RESULTS AND VISUAL OBSERVATIONS OF POLYVINYL ALCOHOL/
BORATE-GEL AND WATER SPRAY AGENT TESTS
Oil Contamination
Before Flushing
P
CO
Test
Series
and
Sarco? es
_
P
c«
3
•i
*2
rt
r^ ffl
•5 5 a
£a
-------
TABLE D-4. SAMPLE RESULTS AND VISUAL OBSERVATIONS OF COREXIT 7664 TEST
Oil Contamination
on Test Area Oil Contamination on Test
Test Backyround Samples Before Flushing Area After Blushing Surface Sample
ana upcer Lower Surface 10-15 cm Surface 10-15 cm Several Hours
Numbers nqA5 n.jA3 ir.qAa i»gA<3 JMA" mqAl mgAg Visual Observations and Comments
L
Q
*1 14 8 G97 29 2990 79 Before flush - 1.5-cm band of oil contamin-
ation
*2 39 64550 89 17290 83 After
beach
SM
33
8 ^
55
91 13 12 48 15 Z1480 23 S-l 13 Bnfore
oil 0.
S-2 5 After
beach
at surface dift'jsing downward.
flush - some visible oil remained
sediments.
flush - occa5ional t*uried band of
OI.
75 en; thick. Some dispersed oil on
flush - oil appeared to flush off
fairly easily.
*1
15
191
1140
26
903
1130
124O
219
S-3 13 Some oil stain reiaained on substrate.
Before flush - 1-cm band of oil contamin-
ation at surface. Test area received larg-
est amount of oil contamination. Some
dispersed oil on water adjacent to test area.
After flush'- oil appeared to flush off
beach. Some oil stain remained on sediments*
-------
Bearing Strength Tests—
Cone pantrcmeter readings were taken of the control and dispersant test
plots before and after the tests were conducted to determine if the use of
dispersants would affect the bearing strength and trafficability of a beach.
The results of the bearing strength survey are shown in liable D-5. As the
table indicates, the use of dispersants did not change the bearing strength of
the test areas.
Discussion
Water Spray System—
The countercurre k. flowing water film produced by the spray system was
the most effective of the three agents in protecting the shoreline from
surface oil contamination, and preventing penetration of oil into the
sediments. Seme beach erosion did occur when the water spray impinging on the
beach eroded a ; *u How trench approximately 15 centimeters wide by 2 to 3
centimeters deep along the length of the spray bar. Although the water spray
system proved to be very effective, it might be difficult and expensive to
implement on a large scale. At the flowrate tested, a punping capacity of
11,340 liters/minute (3000 gpm) woul"! 'oe required for every 300 meters (1000
feet) of shoreline to protect. It is uncertain whether the high flowrate
tested is required. Water spray systems could be used to protect smaller
shoreline areas of high amenity or biologically significant value if the
systems were already constructed and could be ernplaced in a short time.
TABLE D-5. BEARING STRENGTH SURVEY OF TEST AREAS
Averaged Cone Pentrometer* Averaged Cone Pentrometer
Area Readings Before Test Readings After Test
Control 72 75
Corexit 7664
Educted 74 75
Corexit 7664
Nea.: 74 83
* The cone pentrometer readings are a measure of the shearing resistance of
the sediments, and can be directly related to the ability of earth-moving
equipment to operate on the sediments without becoming immobilized. The
range of pentrometer readings (72-83) from Siedler Beach indicate that
rubber-tired earth-moving equipment could operate successfully on that
particular beach.
120..
-------
Pdlyvinyl Alcohcl/Borate-Gel—
' •!
The polyvinyl alcdlTOl/borate-gel agent did not appreciably reduce surface
pil contamination of the shoreline but did appear to prevent oil penetration
into the substrate and to facilitate removal of oil by flushing. The
persistence of : the agent as an intact filir. was approximately one tidal cycle
1 when applied to the upper intertidal area of a low-energy beach * Several
hours to several days are required to formulate the polyvinyl alcohol
solution, depending on how much agent is needed. The formulation requires
that (5% by weight) dry polyvinyl alcohol powder be added to cold water, and
stirred. The water is then heated to 93°C (200°F) /md allowed to cool to room
•temperature. Ihe resulting solution will remain stable for approximately 4
weeks. The time required for formulation and the short duration of
persistence may severely limit the use of polyvinyl alcohol/borate-gel on a
large scale.
jOorexit 7664—
The Corexit 7664 tests were inconclusive in determining its effectiveness
as a protection agent. Gorexit 7664 appeared to reduce initial oil
jcontamination of the beach surface somewhat, as indicated by the cloud of
dispersed oil formed in the surf zone. Kb significant differences in the
.amount of oil initially dispersed as a function of near or diluted application
Was visually detectable.
Application of the agent using a hand sprayer was fairly time-consuming
and would probably not be practical for actual use. Eduction using a fire
hose provided a more acceptable rate of coverage*
"Hie oil was removed by flushing with seawater. Flushing appears to be a
ifactor in the success of the technique. When aimed directly at the oily
{sediment, some oil was removed, but sane also appeared to be mixed more deeply
[into the sediments. Application of water just outside the edge of the oiled
Jzone appeared to float the oil free without this mixing effect. Flushing far
•from the waterline (in dry sediment above the beach water table) was not
successful. The dispersant did not reduce the bearing capacity or'
jtrafficability of the test areas where it was used.
121
-------
APPENDIX D-l
SEDIMENT SAMPLING PROCEDURES
1. During lew tide on the day before each oil spill test, a single
sediment sample is taken frctn the Icwsr intertidal area of each test plot to
be tested en the following day (with the exception of the test plots for OON1,
PVAB, and WFA-B which are to be teted on the first day of the test).
2. Sample collection is carried out using a metal trowel. Sufficient
sample volone is taken frcm the top 6 inches of the substrate to fill a 250-ml
sarnplf. jar (each jar is prewashed with hexane and fitted with an aluninum foil
inner seal to avoid contamination).
3. Chce fitted, each jar is closed and frozen, using dry ice, and storrsd
for analysis at a later date by the EPA.
4. Prior to the daily spill test, the above procedure is repeated for
the q?per intertidal area of each test plot to be tested that day. This
sample and the above-mentioned lower intertidal sample are to be used as
indicators of background hydrocarbon levels. Again, no background samples are
taken for OCN1, PVAB, and WFA-B, which are to be tested on the first day of
the program.
5. Upon completion of the oil spill test, two sets of sediment samples
(four samples in total) are taken in the upper intertidal area of each test
plot, The two locations sampled are situated roughly 1 mater apart in the
middle of the oiled test band in an area showing high oil contamination.
6. Frcni each location, two different samples are taken: one surficial
sample (0-2-inch interval) and one from a depth of 7 inches (5-7-inch
interval). All four samples are collected and stored in the manner described
previously.
7. Fallowing the oonpletion of the flushing portion of the test, this
process is repeated with tvo surface and two subsurface samples taken in the
upper intertidal portion of each test plot (no such sample is taken from WFA-B
since it already involved flushing).
8. A final set of sediment samples (four samples in total) is taken in
the lower intertidal area during the next low tide following the test. These
samples are taken from the area adjacent to the clam cages (roughly 30 to 40
rosters out frcra the base of the beach scarp). Again, two samples are taken
rfron each location sampled, placed in sample jars, and frozen.
122
-------
NOTE: No post-test lower intertidal samples were taken
for CON2, GORE, or CORN, since oil spilled in these test
plots was prevented fran reaching the lower intertidal area
by boons and the prevailing winds.
9. In addition, two sediment samples are taken from the control beach:
one prior to the onset of the test program and one following its completion.
These samples are taken from the top 6 inches of substrate immediately
adjacent to the clam cages. Two additional clair. cage samples are also taken
from the substrate adjacent to the two test beach clam cages following
completion of the test program.
123
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APPENDIX D-2
LABORATORY INVESTIGATION OF IMPROVED MATERIALS
FOR SHORELINE PROTECTION FPOM OIL SPILLS
BACKGROUND AND APPROACH
The API/EPA has sponsored two series of investigations to identify
materials that can be used to prevent contamination of shorelines in the event
of an offshore oil spill. The first program initiated research into the
mechanism of shoreline protection, devloped procedures to evaluate candidate
materials, and recomiended premising agents for use in protecting sandy and
rocky shorelines and salt marsh areas threatened by oil. Three laboratories
(Tracer, Exxon, and Shell) worked independently in this first program and
evaluated polymeric film-forming materials, polysaccharide gels,
microorganisms, inorganic coatings, and surface-active agents.
The second program was contracted to Woodward-Clyde Consultants with URS
Research Company and Texas Rasearch "Instituter Inc. as subcontractors, with
assignee! tasks to compare to a camion baseline reagents reccmnended by the
first investigating laboratories, determine relative agent effectiveness, and
conduct field tests of tha nore premising agents on salt marsh and sandy
beach. A test site was located on Arthur Kill in Vfoodbridge, tfew Jersey, and
tests were conducted during May 1977. The materials selected for field
evaluation represented the protective mechanisms of a continuous polymeric
film, a gelatinous organic coating, a low-concentration surfactant, and a
flowing liquid barrier. The field-tested agents were:
1. Polyvinyl acrylate emulsion, AMSCO-REZ 3011 spray coated
2. 1% solution of xanthan gur spray coated
r-!. Oil Herder sprayed at the shoreline
4. Continuously flowing water
Of these, the polymer film and the polysaccharide gel showed good
protective qualities but, more importantly, the tests indicated deficiencies
in these materials which, if corrected, would greatly improve the overall
performance. Application of the polymer emulsion to a sandy surface resulted
in good coverage but on a rocky or uneven surface tha coverage was not
complete and resulted in coating gaps and subsequent oil penetration. This
effect v«o not noted with the polysaccbaride gel. In addition, the polymer
film did not dry or set ir.ma3iat
-------
j.ifor several months". " The"xanthan gum solution "did not require drying but
lacked tenacity on the beach and was easily removed by wave action.
The objective for the current program- was, therefore, to improve the
Applied _ materials' long- and short-term stability, setting characteristics,
and application properties, without expending a large effort on new materials
development. The approach taken was to rely heavily on the previous programs
for guidance in selecting materials as well as test and evaluation methods.
SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS
The present study was directed to gelatinous materials, polymeric films
with improved properties, and new classes of materials that could be applied
as foam. The project was organized in three phases: identification of new
materials, screening of these materials in the laboratory, and testing on
simulated beaches. On the basis of previous EPA/API report.: and recent
literature, five new materials were selected for study: polyvinyl alcohols,
modified polyvinyl acetate/acrylate, silicic acid gel, soluble starch, and a
polyacrylamide gel. Gelling of polyvinyl alcohol with cross-linking agents to
decrease its solubility .and increase its mechanical strength was studied.
These materials were screened in laboratory tests for ease of preparation and
Application, solubility in salt water, resistance to erosion, resistance to
oil penetration and staining, foam-forming ability, and ability to form
continuous coating. Those with potential for field application were subjected
to testing in an oil spill on a beach simulator. Additionally, studies of the
ultimate degradability of cross-linked polyvinyl alcohol ware made and its
manufacturers were queried for their best opinion of its ultimate breakdown
behavior.
Vfe have concluded from these studies that a high-molecular-'weight, fully
hydrolyzed polyvinyl alcohol, cross-linked with sodium borate, will serve as
jan effective agent to protect beaches from staining and penetration by an
impinging off store oil spill, is environmentally acceptable, and is free front
(drawbacks observed in the application , of polyvinyl acetate emulsions and
xanthan gum gels. Foamed polyvinyl alcohol performed best on a rocky, uneven
beach? an unfoamed gel performed best on a flat, sandy beach. We also noted
jthat the polyacrylamide emulsion, cjeiAod with a cross-linking agent, had many
desirable characteristics, but was flawed by the need for special procedures
and equipment for its application.
Our recoranendations are as follows*:
Highest rank—recommended for field testing:
Cross-linked polyvinyl alcohol foams for rocky shorelines
Cross-linked polyvinyl alcohol gels for sandy beaches
Sicw promise but require special equipment development—not reconmended
for field tests;
Palyvinyl acrylamide gel
125
-------
Soluble starch
lowest raiJi—recommend dropping from further consideration:
Silicic acid gel
RESULTS AND DISCUSSION
Literature Review
A review of pertinent literature including previous API reports on
shoreline protection, manufacturer's data, and other literature dealing with
shoreline protection, oil spills, or hazardous chemical spills was made. A
search of the OTIS data bank for related publications was also conducted. The
literature review is listed in Appendix D-2-1.
Selection of Materials
Data from the previous beach protection program showed that a continuous
polymeric film will prevent oil fron penetrating into the beach and, also,
that gelatinous materials similar to the xanthan gum solution could also act
as a protective agent. More importantly, however, the previous field test
pointed out several deficiencies in both of these materials. The polymar
emulsion used as a continuous film-forming agent worked so wall that it
persisted on tha beach through several norths' exposure to the weather. Film
formation, being dependent on the drying of the applied emulsion, was slow on
a wst beach; in the event of rain it is assumed that film formation will not
occur at all. On the other fand, xanthan gun, while not requiring drying, was
not sufficiently durable en an open beach to provide protection. At the
Sewaren test site, during the application of these tvo materials, xanthan gum
gel was observed to form a mere continuous coating on uneven, rocky sections
of beach than the less viscous polyvinyl acrylate emulsion. In the present
study the following characteristics were sought for a protective agent:
1. The ability to form a continuous polymeric film without the necessity
of drying
2. The ability to form a film tough enough to withstand wave action, but
that can be expected to degrade in a reasonable length of time
3. To have viscosity characteristics that will enable the material to
flow over and fill gaps in rocky, uneven beach areas, as veil as
cover sand
4. To hava sufficient tenacity for the beach to withstand wind and vave
motion
5. To have short-term resistance to solubilization by salt water
6. Tb prevent penetration and staining by oil
126
-------
7. Be relatively nontoxic ^rd environmentally acceptable
Using these characteristics as a basis, five materials were initially
selected:
1. Polyvinyl alcohol cross-linked with Oongo Red
2. Folyvinyl alcohol cross-linked with sodium borate
3. Sodium silicate solution, neutralized to form a gel
4. A proprietary film agent manufactured by Whale Chemical Co.
5. Polyvinyl acrylate emulsion, as in the previous program but with the
addition of a drying and/or degradation accelerating agent
The literature review resulted in the selection of two additional
materials—soluble starch (a high-molecular -weight polysaccharide) and a
low-molecular-weight polyacrylamide vAiich can be cross-linked to form a
sticky/ gelatinous mass. Both of t^se satisfied the requirements of a
protective agent and ware tested in the Laboratory. Materials, suppliers, and
costs are summarized in Table D-6.
Gelling Polyvinyl Alcohol with Cross-Linking Agents
A separate study vras ma^e to determine applicable cross-linking agents to
enhance gelation of polyvinyl alcohol solutions. Stable, as wall as thermally
reversible gels can be formed by reaction of polyvinyl alcohol with a muter
of reagents. Ebur cross-linking agents were investigated: Congo Red, sodium
borate, boric acid, and gallic acid.
; After cross-linking, polyvinyl alcohol becones insoluble in wat»r and
increases in tensile strength. Thus, the advantage of cross-linking polyvinyl
alcohol as applied to the beach is that the cross-linked material resists
dissolution by : impinging waves and maintains its mechanical integrity. TWo
methods were used to introduce the cross-linking agent into the solution. One
was to mix a concentrated solution of the cross-linking agent directly into
the polyvinyl alcohol solution. The second was to apply the polyvinyl alcohol
to a beach substrate and to spray a cross-linking agent over the EVA. In the
first instance, cross-linking agents blended directly into the polyvinyl
ialcohol solution resulted in an uncontrolled reaction. Small concentrations
of cross-linking agents gel polyvinyl alcohol. As agitation and concentration
of the cross-linking material increase, the solutions solidified into a
rubbery mass. Cverepraying polyvinyl alcohol solution with ths cross-linking
agent produced a gel with a tough surface film; polyvinyl alcohol foams
became rubbery. Overspraying was the preferred method used for the remainder
of the testa. The physical characteristics of the cross-linked FVA using each
of the three agents varied and are shown i.» Txible D~7. Briefly, gallic acid
in concentrations up to 10% by weight of resin, slightly hardened polyvinyl
alcohol films wrvsn cversprayod and only thickened a PVA solution. Congo Red,
in concentrations of frcm 0.2% to 2% by weight of resin, coagulated the FVA
into a galatirdus rod mass in solution and produced a gelatinous surface when
127
-------
TABLE D-6. MATERIALS StiMMARY
Material
Foiyvinyl Alcohol
Elvar.ol HV-L7DQOG
Polyvinyl Alcohol
Elvanol 90-50 F
Polyvinyl Alcohol
Geluatol 20-30
Polyvinyl Alcohol
Vir.ol 165
H
oo Poly vinyl Alcohol
Vinol 205
Polyvinyl Alcohol
Vinol 523
Polyvinyl Acrylate
Amsco-Res 3011
Polyacrylamide
XD- 30123. 01
Soluble Starch
Sodium Silicate
Form (as Supplied)
Powder
Powder
Powder
Powder
Powder
Powder
Liquid Emulsion
55% Solids
Liquid
Powder
Powder
Supplier
DuPont
DaPont
Monsanto
Air Products
Air Products
Air Products
Union Oil
Dow Chemical
Bon Ami Co.
Baker Chemical
Cost (?/lb)
S/kg
(1.47)
3.24
(1.52)
3.35
(0.875)
1.93
(0.805)
1.78
(0.735)
1.62
(0.775)
1.71
(0.32)
0.706
(0.30)
0.662
(0.436)
0.961
(0.475)
1.05
Cost as Applied
($/gal) $/liter
(0.612)
0.162
(0.633)
0.167
(0.364)
0.140
(0.3i?)
0.089
(0.306)
O.OB1
(O.J23)
0.085
(2.930)
0.774
(1.250)
0.330
(0.0728)
0.0192
(0.187)
0.0494
Cost (5/mile)
1436
1481
1242
783
718
754
6865
2927
170
438
* Beach area 1 mile long x 10 feet wide.
-------
TABLE D-7.- POLYVINYL ALCOHOL CROSS-LINKING AGENTS
Agent
Congo Red
Congo Red
Boric Acid
Boric Acid
Borax
Borax
PVA Cone.*
(Wt. %)
5
5
5
5
5
5
Agent Cone.
(% Resin)
.2
2
Saturated
Solution
Saturated
Solution
Saturated
Solution
Saturated
Solution
Results
Red gelatinous clots formed.
Thicker clots formed.
Dripped into PVA with stirring —
thickened and formed solid clumps .
Misted over PVA — formed surface
skin on contact — PVA thickened on
standing
Dripped into PVA with stirring —
. thickened and formed solid clumps.
Misted over PVA — formed surface
skin on contact — PVA thickened on
standing.
Gallic Acid
Gallic Acid
5
5
10
10
Slow thickening of PVA solution.
Thin gelled skin formed when
sprayed over PVA surface.
* Elvanol HU-L7D006.
129
-------
over sprayed on a coated beach. The borates, sodium borate and boric acid,
both produced very rapid coagulation of F/ft in solution, and when oversprayed
on a coated surface, inmediately hardened the surface into a tough film.
Because of the durability of the borate-treated polyvinyl alcohol, the
relative low cost of the borates, the rapidity of the reaction and low
toxioity, sodium borate was chosen as a cross-linking agent for use in the
remainder of the tests.
Laboratory Screening
Samples of the materials enumerated on page 127, excepting the Whale
Chemical Co. agent which was not available, were obtained for laboratory
testing. Polyvinyl alcohols of low to high molecular weight and low to high
degrees of hydrolysis were received. In general, molecular weight affects
vater solubility viscosity, and dry strength; degree- of hydrolysis affects
the alcohol's reactivity in cross-linking. While polyvinyl alcohol is only
slightly soluble in cold water, the solubility limit is approximately 20% in
hot water. Five percent solutions of six different polyvinyl alcohol
formulations were prepared for laboratory screening. Gels of soluble starch,
cross-linked polyacrylairu.de, and silicic acid were also prepared. Bench-scale
procedures designed to test for the criteria set out on page 126 were
performed. Detailed descriptions of these tests and preparation procedures
are presented in D-2-2. Since little of the data gathered was of a
quantitative nature, a scoring protocol of pluses or minuses was utilised.
Ihe better results are indicated by more pluses; negative attributes by
minuses. Ihe results of these tests are presented in Table D-8.
Simulated Beach Tasting
The simulated beach system used to test agents in this program is
essentially the same as that used on the previous API program. Three beaches
with an area of 0.334 square meters each were attached to a mechanism that
pocked the beaches through a 30-degree arc every 2 seconds. The beach
surfaces were made of unwashed river sand and placed in the beach containers
to a depth of approximately 3 inches. The agents to be tested were applied to
one half of the beach surface; the untreated half served as a control.
Agents were applied to beaches prewetted with 3.5% salt water. After drying,
the appearance and texture of the coatings were noted. Approximately 2.0
liters of salt vster were then added to the beaches and rocking was continued
for 1 hour. Observations were then made of erosion, dissolution, or
displacement of the coatings. Test oils, Kuwait crude and No. 2 fuel oil -were
fcdded and the beaches again rocked for another hour. After the second hour,
the water was drained from the beach, appearance was noted, and residual oil
was washed fron the beach surface with a stream of water. Observations again
Were made on the ability to remove the oil fron the surface. Vertical
Sections of the beaches were then examined for oil penetration and staining.
The results of these teats are given in liable D-9.
Additional Tasting
It became apparent during the course of the laboratory phase of this
program that materials not tested or combinations of materials not tested
130
-------
TfcELE D-8. IABORRTORY SCREENING SUMMARY
Material
Elvsr.ol
KN-L7DC06
Elvanol
30-50F
Vinol 105
Vinol 205
H1
W Vinol 523
Gelvatol
20-30
AKSCO-REZ
3011
Soluble
Starch
Sodium
Silicate
Polyacryl-
amide
Fort"
Gel
Foam
Gel
F&ara
Gel
Foam
Gel
Foam
Gel
Foam
Gel
Foaa
Emulsion
4% gel
Gel
Gel
preparation
Foam Expansion
Application % * at
Erosion Resistance* Staining/
Method Rating Hethod Rating Initial 17 Hrs Rating Coverability* ml Ratir.q Clt-anability
Mix w/heat +
Mix w/hcat +
Mix w/heat +
Mix w/heat +
Mix w/he^t +
Mix w/hcat +
Mix w/heat +
Mix w/heat +
Mix w/heat +
Mix w/lieat +
Mix w/heat +
Mix w/heat +
As Rcvd. +
Mix s heat +
Mix & Acidify
Crosslink
w/rcagents
four/spray + 137 50 *
Pour/spray +
Pour/spray •<- 175 25 +
Pour/spray +
Pour/spray + 137 SO +
Pour/spray +
Pour/spray + 312 Trace +
Pour/spray +
Pour/spray + 237 75 +•
Pour/spray +
Pour/spray + 337 0 +
Pour/spray +
Pour/spray +0
Pour hot. - • 0
allow to cool
Poar +0
Preaiix and - 0 -
rapidly pour
+ 2GO * +
200 + -f
90 +
180 + +
* 130 + *
100 + +
+ Did not erode + +
+ 50 -
5 - -
N/A N/A N/A N/A
* Polyvinyl alcohol cross-linked with borax
+ - Acceptable
- - Unacceptable
-------
TABLE D-9. ^SIMULATED BEACH SUMMARY
Material
Elvanol
KV-L7D006
Elvanol
90-50F
Vinol 105
Vinol 205
Vinol 523
Gelatol 20-30
AMCO-REZ 3011
Sodium
Silicate
Application Erosion Kuwait #2 Oil
Gel - .N/A N/A
not cross-
linked
Gel/Borax + + +
Foam/Borax + + +
Gel/Borax + . + +
Foam/Borax + +
Gel/Borax - + +
Foam/Borax - + +
Gel/Borax + + +
Foam/Borax - + +
Gel/Borax + + +
Foam/Borax + + +
Gel/Borax + +
Foam/Borax - + +
Emulsion + + +
Gel - - -
Overall
- (rapid erosion)
+
+ (edges tended to lift from sand)
- (low strength)
- (low strength)
- (low strength)
+
- (low strength)
+
+
- (low strength)
- (low strength)
- (long drying time required)
- (very short persistence)
-------
showed promise for use in shoreline protection. Included in these materials
is a inixture of polyvinyl alcohol, and silicate gel, a mixture of water-soluble
starch and rDlyvinyl alcohol, and other polyelectrolytes similar to the
polyacrylamide. Brief laboratory observations were made but a detailed
investigation of these materials could not be made within the scope of the
program. These observations are given in Table D-10.
None of the procedures outlined under laboratory screening and beach
simulation testing address the ultimate degradability of coating materials.
Ihis was determined, in the Sewaren field tests, to be a defect of the
polyvinyl acetate/acrylate coatings. To gain insight into this process two
mini-tests were conducted. First, test patches of sand were prepared and
coated with polyvinyl alcohol solution, polyvinyl alcohol foam, both of these
cross-linked with sodium borate, and polyvinyl acetate/acrylate emulsion.
These patches were allowed to dry thoroughly. Sections were cut from the test
plots, iinmersed in salt water, and allowed to soak. Intermittent observations
showed the uncross-linked polyvinyl alochol to hydrate to a mucilaginous film
that could be broken or separated between the fingers after a day or two, and
the acetate/acrylate copolyirar film to lose little of its initial strength or
toughness after 3 weeks.
TABLE D-10. MIXTURES AND OTHER MATERIALS
1. 5% Polyvinyl alcohol, uncross-linked - 1% Silicic Acid Gel
Can be foamed. Foam stabilized by silicic acid gel.
Drying time increased.
Dried foam discontinuous and crumbly.
2. 28% Polyvinylacetate/acrylate - 2% Soluble Starch
Dries to a hard, tough film.
Film softens only slightly during one-week exposure to salt
water.
3. Polyacrylamide Gel
Forms dense gel that cannot be poured.
Dries very slowly, but rehydrates to its original form.
High resistance to erosion by salt water.
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To study the breakdown of dried film of these materials, these films were
prepared by dipping circular loops of stainless steel wire. Dried samples
were exposed to bright sunshine all day for one week while controls were
stored in a dark cabinet. Daily observations during tMs period showed no
change in the color, texture, or brittleness of the exposed samples. At the
end of a week's exposure infrared trarisnittance spectra of the film showed no
evidence of ultrviolet-induced chemical decomposition. On the eighth day of
exposure the outdoor samples were inadvertently briefly subjected to brief
morning mist, after which they were brought inside to dry. On drying, all of
the polyvinyl alcohol films shrunk and curled—the polyvinyl acetate/acrylate
films were unaffected. Ws feel the capacity of the polyvinyl alcohol films to
readily hydrate and their tendency to shrink and curl on drying will cause
mechanical degradation of applied film in a reasonably short period in the
moist environment of the beach.
EQUIPMENT REQUIRED FOR CM-SITE APPLICATION
The solutions recommended for field test of this program can all be
pumped through standard centrifugal or positive-displacement purps. However,
for application of foam, special pumping systems must be used. Several
varieties of foam-generating equipment are commercially available for
application of foam to fires, application of insecticides, and for other
purposes where expanded solutions are required. In general, foam generators
work by injecting air into a stream of the fluid being pumped and dispensing
the fluid/air mixture through a sized screen to control the resulting foam
bubbles. For the purpose of field testing, a limited amount of foamed
material could bs generated by using a carcnercial foam pump, or by foaming in
a container, such as a 55-gallon drum fitted with a high-speed mixer. The
resulting foam could then ba poured on the surface to be coated. Application
of cross-linking agents required for polyvinyl alcohol can be accomplished
through use of hand-held garden-type sprayers.
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APPENDIX D-2-1
" BIBLIOGRAPHY"
1. Sunmary Report of Phase I Evoluat-Lon of Selected Surface Treatment
and Agents. Vtoodward-Clyde Consultants. August 1970.
2. Sumnary Report of Phase II Laboratory and Preliminary Field Testing
of Selected Surface Treatment Agents. Woodward-Clyde Consultants.
February 1977.
3. Final Report, Beach Protection Study. Tracer, Inc. July 26, 1974.
4. Methods to Treat, Control and Monitor Spilled Hazardous .Materials.
Calspan Corp. June 1975. (OTIS PB-243 386)
5. Control of Hazardous Chemical Spills by Physical Barriers. MSA
Research Corp. March 1973. '(OTIS P 13— 221 493)
6. Toxic Substances List. NI.OSH.1 1977.
7. Toxicologic Investigations of Polyacrylsmids . D D. McCollister, et
al. Toxicology and Applied Pharmacology, Vol. 7, ND. 5. September
1965.
8. The Chesnistry of Silicic Acid. S. A. Greeriberg, J. of Chemical:
Education. Vol. 36, No. 5. May 1959.
9. Control of Spillage of Hazardous Polluting Substances. . G. W. Dawson
et al. Battelle Manorial Institute. Richland, Washington. Ndveraber:
1970. (NTIS PB 197 596)
10. PolyvinylalcolTol . C. A. Finch, John Wiley & Sons, Naw York. 1973.
11. The Ecological Significance of Boron. Sprague. U. S. Borax Research.
Corp., Anaheim, California. 1972.
12. Shoreline Protection and Restoration Fran Oil Spilla. Final Report.
Research and Engineering Co. September 1974.
13. Review o£ Agents and tethodo fior Ehorelina Protection. Final Report.'
Texas Research Institute, Inc. February 11, 1977.
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14. PDly(vinylalcx3hol). J. G. Prichard. Gordon and .Breach Science
Publishers. New York. 1970.
15. Evaluation of Selected Surface Treatment Agents for the Protection of
Beaches and Salt Marshes fran Oil Contamination.. Final .Report.
Woodward-Clyde Consultants.
16. Development of a Nfcbile Treatment. System for Handling Spilled
Hazardous Materials. M. K. Gupta. " Envix-ex, Inc. " EPA Contract
No. 68-01-0099. July 1976. (NTIS EPA-600/2-76-109)
136
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APPENDIX D-2-2
PREPARATION.OF MATERIALS AND SCREENING TESTS-
. PREPARATION
Polyvinylaloohol Solutions
Polyvinylalcohols (5% by-weight), granular or powder, was added to cold
water with stirring to form a slurry. "The slurry was heated under continuous
stirring until all turbidity disappeared. This occurred at 65°-70^C. Kb
significant increase in viscosity was noted in eolution of this concentration
on cooling.
Polyvinylacrylate (AMSCO RES-3011)
No preparation necessary. Apply as received.
Soluble Stfjrch
Soluble starch (4% by weight) was added to cold water with stirring to
form a suspension. The suspension was heated with stirring until no further
decrease in turbidity could be noticed. This occurred near 10sPc. • Upon
cooling/ the solution fornied a viscous gel.
Silicic Acid Gal
A solution of soditm rneta-silicabe (1%, based on SiO- content) was
prepared in cold water. Th.e pH of this solution was adjusted to 8.5 by
dropwise addition of concentrated 1321 vath-stirring, -The solution, was then
pillowed to stand. A dense mucilaginous driable gel formed vathiii 15 minutes.
gQlyacrylcgnida (Dow XD-30123.01)
TVJO solutions were prepared:
1* 0.75 ml; of 40% glyoxal was addad to 10-0 g of polyacrylcmlde emulsion.
2. 1.5 g of Na3P04 12^0 in 100 g of ILp.
The two solutions were poured together and rapidly stirred. A tenacious
gel formed with 2 to 3 minutes.
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FOAMABIIJTY./POAM STABILITY
Two hundred ITI! of each agent were placed in a Vfering blender and stirred
at high speed for 60 seconds. The volume of the resulting foam was measured
in a graduated vessel and the time required for the foam to collapse was
observed.
RESISTANCE TO STAINING AND OIL PENETRATION
Test objects (a wooden stick, a glass microscope slide, a patch of glass
fixer cloth) wera coated with the protective agent. The objects were allowed
to dry, dipped briefly into a solution of salt water, then dipped into a
vessel of =rude oil. The tenacity of the oil was observed. The object was
then rinsed with a stream of water and again examined for oil staining or
penetration.
COVERING ABILITY AND EROSION RESISTANCE
Twenty-cm squares of screen wire were dipped in preparations of each
protective agent and withdrawn. The squares were then allowed to dry.
Con^jleteness of coverage was noted. A 3.5% salt solution (simulating sea
water) was allowed to drip onto each" material at a" rate of 60 to 70
drops/minute fran a height of 30 on. The volune of solution required to break
through the coating was recorded.
••138
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APPENDIX D-2-3
DETAILED PREPARATION PROCEDURES, RECOMMENDED AGENTS
The recormended agent is high-molecular-weight, fully hydrolized
polyvinyl alcohol (DuPont Elvanol HV or equivalent). This material is
available as a powder in 50-lb bags.
The PVA is prepared as a 5% by weight solution (0.44 Ib PVA per gallon
tiJD in fresh vater) using the following procedure:
1. Add the weighted powder to a taiown volume of fresh, cold water Vvhile
mixing. A 55-gallon drum can be used with an electric drun-type
mixer.
2. Heat the mixture vJiile stirring to approximately 200°F to dissolve
the PVA. The solution will become clear when the powder dissolves.
Two or three external band heaters, Chrcmalox PFD-130 SG (120 volt,
1500 watt) or equivalent/ should be used along with a minimum of 2
inches of external fiberglass insulation.
3. Allow the solution to cool with the container covered to prevent
evaporation. The solution can be stored for 4 to 6 weeks before use
if desired.
2
PVA application to the beach is at the rate of 1/2 gall'on/m .
The borate solution is made using sodiun tetraborute decahydrate
(dissolved in water at the rate of 30 cjn/liter (.25 Ib/gal). This is ordinary
borax available at a grocery store. Stir or shake the mixture until
completely dissolved.
Apply the borax solution over the PVA on sand or gravel in a fine spray
at the minimm rate of 30 ml/m (1/8 oz/cn ). Excess borax will not decrease
the effectiveness of the FVA coating. .;
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APPPENDIX D-2-4
RECOMMENDED AGENT TCKTCITY
POLYA/INYL ALCOHOL
Polyvinyl alcohol is generally considered nontoxic. It is approved toy,
the FDA for food contact applications and is widely used in contact with skin
as a textile sizing. PVA is not listed in the NTOSH Registry of Toxic
Materials.
In water, PVA has baen reported (Long-Term Biochemical Oxygen Danand of,
Elvanol Polyvinyl Alcohol, E. I. DuPont de Nsmours & Co., 1970) to have a BOD
(% by weight oxygen consvsned) of 1% at 5 daya and 3% at 30 days. PVA would
therefore have little, if any, effect can aquatic life.
BORAX
Data has baen presented (R. W. i^ragua. The Ecological Significance of
Boron, U. S. Borax Research Corporation, JSjiahsim, California, 1972) indicating
the toxicity of borax as follows: ' i
iJDgg (rats): 4.5 - 6.1 gra/kg
Minimum lethal dose (minnows): 1.9% in HJ3
Boron compounds can affect plant growth. Tolerant crops can be grown in
soils containing up to 3.75 ppn boron (32 pptn as borax). Sea water contains
an average concentration of 4.6 ppm boron. The amount of borax recommended
for beach applications .(900 itg/m ), when dispersed in sea water, is no*-
expected to adversely affect marine plant growth.
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