National Academies Press: OpenBook

Using Oil Spill Dispersants on the Sea (1989)

Chapter: Front Matter

Suggested Citation:"Front Matter." National Research Council. 1989. Using Oil Spill Dispersants on the Sea. Washington, DC: The National Academies Press. doi: 10.17226/736.
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Using Oil Spill Dispersants on the Sea Committee on Effectiveness of Oil SpiB Dispersants Marine Board Commission on Engineering and Technical Systems National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1989

National Academy Press · 2101 Constitution Avenue, N.W. · Washington, D C. 20418 NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the panel responsible for the report were chosen for their special competences and with regard for appropriate balance. This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Manly Press is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Robert M. White is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Samuel O. Thier is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies deter- mined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Frank Press and Dr. Robert M. White are chairman and vice-chairman, respectively, of the National Research Council. The program described in this report is supported by Cooperative Agreement Nos. 1~12-0001-30301 and 14-12-0001-30360 between the Minerals Management Service of the U.S. Department of Interior and the National Academy of Sciences. Library of Congress Cataloging-in-Publication Data National Research Council (U.S.). Committee on Effectiveness of Oil Spill Dispersants Using oil spill dispersants on the sea / Committee on Effectiveness of Oil Spill Dispersants, Marine Board, Commission on Engineering and Technical Systems, National Research Council. p. cm. Bibliography: p. Includes index. ISBN ~309-03882-0 (paper); ISBN 0-309-03889-8 (cloth) 1. Oil pollution of the sea. 2. Dispersing agents. 3. Oil spills—Environmental aspects. 4. Dispersing agents—Environmental aspects. I. Title TD427.P4N38 1989 626.1/6833—dc 19 8~38879 CIP Cover: The slate-blue color common to the surface of the northern seas and windrows—or parallel mases—of undispersed oil are reflected in the artist's rendition on the cover of this report. Copyright (I) 1989 by the National Academy of Sciences No part of this book may be reproduced by any mechanical, photographic, or electronic process, or in the form of a phonograhic recording, nor may it be stored in a retrieval system, transmitted, or otherwise copied for public or private use without written permission from the publisher, except for the purposes of ofl~lcial use by the U.S. government. Printed in the United States of America

Acknowledgments The extensive reference list on which this report is based could not have been compiled without the assistance of many scientists and engineers throughout the world. Members of the committee obtained and provided unpublished reports and reports of work in progress that were essential for our discussions. ~ particular, Mervin Fingas of Environment Canada, Ottawa, provided the committee with a full shelf of reports and symposium proceedings. The Environment Canada Library, Dartmouth, and the Fisheries and Oceans Library at the Bedford Institute of Oceanogra- phy, also in Dartmouth, Nova Scotia, helped with literature searches. Two members of the committee served as vice-chairman in charge of a working group: Colin Jones chaired the group concerned with effectiveness and participated in the Beaufort Sea dispersant tests conducted in August 1986 by Environment Canada. Peter Wells, as vice-chairman of the biological working group, acquired and as- sessed an immense body of published and unpublished literature, and summarized it for the committee. These activities represented considerable extra commitment, and are especially appreciated. James N. Butler Chairman · · ~

COMMITTEE ON EFFECTIVENESS OF OIL SPILL DISPERSANTS JAMES N. BUTLER, Chairman, Harvard University, Cambridge, Massachusetts LARRY P. ATKINSON, 01d Dominion University, Norfolk, Virginia JOHN P. FRASER, Shell Oil Company, Houston, Texas MICHAEL J. HERZ, Tiburon Center for Environmental Studies, San Francisco State University, Tiburon, California COLIN M. JONES, Consultant, Colin M. Jones Associates, Arlington, Virginia JAMES P. MARUM, Mobil Oil Corporation, Princeton, New Jersey CLAYTON D. MCAULIFFE, Consultant, Clayton McAuliffe and Associates, Inc., Fullerton, California ROBERT J. MEYERS, Consultant, Robert J. Meyers and Associates, Houston, Texas L. A. "SKIP" ONSTAD, Clean Seas, Carpenteria, California JAMES R. PAYNE, Science Applications International Corporation, I,a Jolia, California JOHN M. TEAL, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts PETER G. WELLS, Conservation and Protection, Environment Canada, Dartmouth, Nova Scotia, Canada Staff DONALD W. PERKINS, Staff Officer ANDREA CORELL, Editor GLORIA B. GREEN, Senior Secretary 1V

MARINE BOARD SIDNEY WALLACE, Chairman, U.S. Coast Guard (retired), Reston, Virginia RICHARD J. SEYMOUR, Vice-Chairman, Scripps Institution of Oceanography, La Jolla, California ROGER D. ANDERSON, Cox's Wholesale Seafood, Inc., Tampa, Florida KENNETH A. BLENKARN, Amoco Oil Company (retired), Tulsa Oklahoma DONALD F. BOESCH, Louisiana Universities Marine Consortium, Chauvin C. RUSSEI,I, BRYAN, U.S. Navy (retired), St. Leonard, Maryland F. PAT DUNN, Shell Oil Company, Houston, Texas JOHN HALKYARD, Arctec Offshore Corporation, Escondido, California EUGENE H. HARLOW, Soros Associates Consulting Engineers, Houston, Texas DANA R. KESTER, University of Rhode Island, Kingston JUDITH T. KILDOW, Massachusetts Institute of Technology, Cambridge WARREN G. LEBACK, Consultant, Princeton, New Jersey WlI,I`lAM R. MURDEN, Murden Marine I'td., Alexandria, Virginia EUGENE K. PENTIMONTI, American President I.ines, I.td., Oakland, California JOSEPH D. PORRICEI,I`T, ECO, Inc., Annapolis, Maryland ROBERT N. STEINER, Atiantic Container l.ine, South Plainfield, New Jersey BRIAN J. WATT, TECHSAVANT, Inc., Kingston, Texas EDWARD WENK, JR., University of Washington (retired), Seattle Staff CHARLES A. BOOKMAN, Director DONALD W. PERKINS, Associate Director DORIS C. HOLMES, Administrative Associate DELPHINE GLAZE, Administrative Secretary AURORE BLECK, Senior Secretary GLORIA B. GREEN, Senior Secretary CARLA M. MOORE, Senior Secretary I, v

Preface Exploring the potential of chemical dispersants to combat open- sea of} spills has been attractive to both government and industry. However, an unanswered question is whether testing and technical advances in the laboratory and in the field, and progress in deploy- ment, justify the use of dispersants as a primary response technique. Much of the dispersant research in the United States has been conducted by private industry. In addition, research was conducted by the Interagency Technical Committee for the Oil and Hazardous Materials Simulated Environment Test Tank (OHMSETT) facility. The committee included the Minerals Management Service of the Department of the Interior, the U.S. Coast Guard, the U.S. Navy, the Environmental Protection Agency, and Environment Canada. Further, a major amount of dispersant research has been done in Canada, sponsored by Environment Canada. Significant research also has been conducted by industry and by others abroad, most notably in France, Norway, and the United Kingdom. In view of the extent of recent research, U.S. and Canadian cooperating agencies requested that the National Research Council (NRC), "review the state of knowledge in toxicity, effectiveness of application techniques, and effectiveness of commercially available dispersants." In response, the Commission on Engineering and Technical Systems of the NRC convened the Committee on Effectiveness of Oil Spill Dispersants. Members of the committee were selected for their experience in .. V11 I

· · ~ V111 PREFA CE and knowledge about the fates and effects of petroleum in the marine environment, physical chemistry of pollutants, physical and chem- ical oceanography, marine biology and zoology, of} and hazardous materials cleanup techniques and management, of} spill contingency planning and response, marine engineering and field deployment, and public interest in environmental protection. A balance of technologi- cal, scientific, and geographic perspectives was a major consideration in the selection of the committee. Consideration of public concern about environmental safety was another major consideration. SCOPE OF STUDY The committee was charged to assess the state of knowledge and practice about the use of dispersants in responding to open-ocean of! spins. This assessment wid guide federal and local governments and industry in both the United States and Canada, in defining the role of dispersants in oil spin response and implementing the use of dispersants. Equally important is the charge to identify gaps in knowledge where research is especially needed. The committee was specifically asked to · determine the effectiveness of dispersants and identify the best techniques for their use; · identify the possible impacts of dispersants and dispersed of} on marine and coastal environments; and · provide guidance about when and where dispersants should or should not be used. The committee interpreted these charges broadly, and addressed two fundamental questions: Are dispersants effective that is, do the chemicals remove oil from the surface of the sea and disperse it into the water column? Is the biological impact of dispersed oil greater or less than that of untreated oil? In answering these questions, the committee also identified where knowledge is lacking and what research is fundamental to improving effective and responsible use of dispersants. While the focus of the assessment was on the use of dispersants in the open ocean, the committee examined the possibility of impacts on important characteristics of the marine environment tropical, temperate, and polar coasts, areas important to marine life cycles, and ocean areas frequented by marine mammals and bird life. Government policies were addressed only to the extent that they

PREFA CE IX affect optimum use and deployment of dispersants and international cooperation in their assessment and application. The committee determined that a detailed assessment of compar- ative costs for using dispersants for treating a spin and for mechanical cleanup and disposal would be beyond the charge given to the com- mittee. However, since this topic could be a significant element in the decision-making process about the choice of response techniques, a summary giving a range of costs and important references has been provided in the text for the interested reader. METHOD OF STUDY Data and information about dispersant use and its effects were acquired from Canadian and U.S. sources through the auspices of the sponsoring agencies, with extensive input by Environment Canada. A significant contribution was the evaluation of literature on Com- parative Field Effects of Dispersed and Undispersed Petroleum Oils in Coastal Marine Environments, prepared at the request of the com- m~ttee by P. Lane and Associates Limited, Halifax, Nova Scotia. This work was conducted under the guidance of Peter Wells, a member of the committee. Canadian, European, and U.S. experiences and data were also acquired through background papers written by committee members and reviewed during the Workshop on Oil Spill Dispersant Effec- tiveness held March 24-26, 1986, at Reston, Virginia. Participants included guests from British, Canadian, French, and U.S. research institutions and industry. They were Gerard Canevari, Exxon Re- search and Engineering Company, Houston, Texas; Jean Croquette, Centre de Documentations sur le Pollutions Accidentelles de Eaux (CEDRE), Brest, France; Merv Fingas, Conservation and Protection, Environment Canada, Ottawa, Ontario; Richard Golob, World Infor- mation Systems, Inc., Cambridge, Massachusetts; David Kennedy, National Oceanic and Atmospheric Administration, Seattle, Wash- ington; Gordon Lindblom, Exxon Chemical Company, Houston, Texas; Donald MacKay, University of Toronto, Ontario, Canada; and Joseph Nichols, The International Tanker Owners Pollution Federa- tion Ltd., London, England. Information was also received from D. Cormack, Warren Spring Laboratory, Stevenage, England. The assessment process of the report development was under- taken in two subsequent meetings and was based on test data as weD as on observations of field experience, including field trials conducted

PREFA CE by Environment Canada, August 1986, in the Beaulort Sea, North- west Territories. These field trials were witnessed by Colin Jones, a committee member, at the invitation of the Canadian government. The committee report and its conclusions and recommendations re- flect a broad data base and assessment in the marine toxicological and biological area. A more limited data base supports the field ap- plications and experience area; however, field observation enhances the experience basis for the committee's conclusions and recommen- dations in that area.

Contents EXECUTIVE SUMMARY .................... Do They Do Any Good?, 1 Do They Do Any Harm?, 3 Recommendations for Using Dispersants, 4 Suggested Research, 5 1 USE OF OIL DISPERSANTS: HISTORY AND ISSUES ............................................ Reasons for Treating Oil Spills, 6 Aesthetic and Ecological Damage, 6; Economic Damage, 7; Safety Hazards, 9 Potential Sources of Spilled Oil, 9 Treatment Methods, 13 Mechanical Containment, Recovery, or Removal, 14; Shoreline Cleanup, 16; Natural Removal, 17; Other Countermeasures, 17 Role of Dispersants, IS Rationale for Dispersant Use, IS; Sea and Weather Conditions, 18; Logistics, 19; Protection of Ecologically Sensitive Areas and Organisms, 19; Protection of Fisheries Resources, 19; Protection of Shoreline X1

·— X11 Amenities, 20; Dispersants as an Aid to Natural Cleanup, 20 History of Dispersant Use, 21 The Torrey Canyon Spill, 21; Development of New Formulations, 22; Development of Equipment, 23; Case Studies, 24 Issues and Questions, 24 Using Chemical Dispersants to Remove Oil From the Surface of the Water, 24; Factors Affecting Toxicity of Chemical Dispersants and Dispersed Oil, 26 2 CHEMISTRY AND PHYSICS OF DISPERSANTS AND DISPERSED OIL....................... Composition of Dispersants, 29 Chemistry of Surfactants, 29; Current Dispersant Formulations, 31; Matching Dispersant Formulations With Oil Type for Increased Effectiveness, 34; Fate of Surfactants and Solvents in the Aqueous Environment, 35 Fate of Oil Spilled on Open Water, 36 Slick Thickness, 36; Slick Spreading, 38; Physical Processes of Dispersion Related to Water Motion, 41; Evaporative Loss of Volatile Hydrocarbons, 47; Photochemical Processes 49; Mousse Formation, 49 Behavior of Oil-Dispersant Mixtures, 50 Criteria for Effective Dispersal, 50; Relation of Oil Composition to Dispersibility, 51; Effect of Oil Viscosity, Time, and Other Parameters on Dispersion, 54; Effect of Dispersant on Slick Dynamics, 57; Behavior of Droplets and Resurfacing, 58; Interaction of Dispersed Oil With Suspended Particulate Matter and Sediment, 62 Oil Fate and Dispersion Models, 63 Mode! Types, 63; Nonuniform Slick Thickness, 65; Advection and Diffusion, 65; Resurfacing, 65; Breaking Waves, 65; Integrated Approaches, 66; Mode} Validation, 69; Summary, 69 CONTENTS .28

CONTENTS Laboratory Studies of EEectiveness, 70 Purpose of Laboratory Testing, 70; Critical Factors, 71; Need for Standard Testing Oils, 73; Advantages aunt Disadvantages of Testing Methods, 74; Summary, 78 Need for Research, 79 3 TOXICOLOGICAL TESTING OF DISPERSANTS AND DISPERSED OIL............................... Overview of Toxicological Testing, 81 Toxicological Testing Methods, 83; Dispersant Screening Procedures for Toxicity Considerations, 84; Dispersant Screening Procedures in Canada, the United States, and Other Countries, 85 Toxicity of Dispersants, 96 Acute Toxicity of Components, 97; Acute Toxicity of Formulations, 100; Factors Influencing Acute Toxicity, 110; Sites and Physiology of Toxic Action, 117; Sublethal Ejects, 118; Hazard Assessment of Dispersant Alone, 122 Toxicity of Dispersed Oil, 123 Exposure Assessment, 124; Factors Affecting Comparative Toxicity, 124; Joint Toxicity, 125 Laboratory Studies With Dispersed Oil, 126 Phytoplankton, 130; Macroscopic Algae and Vascular Plants, 130; Zooplankton, 131; Crustaceans, 135; Mollusks, 146; Comparison of Laboratory Studies and Field Studies With Measured Hydrocarbons, 147; Summary, 154 Microbial Degradation, 155 Laboratory Studies, 156; Mesoscale Studies, 157; Microbial Field Studies, 158; Summary, 159 Seabirds and Marine Mammals, 160 Seabirds, 160; Marine Mammals, 163 4 INTERMEDIATE-SCALE EXPERIMENTS AND FIELD STUDIES OF DISPERSANTS APPLIED TO OIL SPILLS........................................ · .— X111 ..... 81 .165

XIV Physical and Chemical Studies, 165 Intermediate-Scale (Mesoscale) Studies, 166; American Petroleum Institute Research Spills, 168; Protecmar, 173; North Temperate and Arctic Tests, 175; Summary of Physical and Chemical Field Test Results, 179 Biologically Oriented Mesocosm and Field Studies, 183 Algal, Zooplankton, and Microbial Populations, 183; BIOS Arctic Studies, 188; Temperate Shallow Subtidal and Intertidal Habitats, 193; Temperate Shallow Subtidal Studies: Long Cove and Sequlm Bay, 198; Fish, 200; Tropical Shallow Intertidal and Subtidal Habitats, 201 Summary, 208 5 HOW DISPERSANTS ARE USED: TECHNIQUES, LOGISTICS, MONITORING, AND APPLICATION STRATEGIES . e · e · e · e e · ~ ~ e · - e e e e e e e e e e e e · - - - ~ e e e e e · ~ - - Design of Dispersant Application Systems, 215 Spray Systems, 215; Spray Droplet Size, 216; Dispersant Type, 220; Dosage Control, 221; Boats, 222; Aircraft, 224; Helicopters, 226; Hydrofoils and Hovercraft, 226; Boats Versus Aircraft, 228; Calibration, 228 Monitoring Effectiveness of Dispersants, 229 Remote Sensing, 230; Visual and Near-Visible Observation, 231; Infrared Sensing, 232; Microwave Sensors, 233; Summary of Monitoring Techniques, 233; Regulatory Requirement, 234 Strategy of Dispersant Applications, 234 Dispersability of Oil, 235; Spill Size and Configuration, 235; Aerial Spraying Strategy, 236; Other Strategies, 236; Command and Control, 237; Weather, 238 6 TECHNICAL BASIS OF DECISION MAKING. Findings From Previous Chapters, 239 Technical Questions, 240 Response Options, 241; Environmental CONTENTS ....... 215 .239

CONTENTS Considerations, 241; Other Factors That Affect Decision Making, 241 Advance Planning, 243 Decision Schemes, 244 U.S. EPA Oil Spill Response Decision Tree, 245; API Decision Diagram, 245; SLR Dispersant Decision-Making Workbook, 247; State of Alaska Dispersant-Use Guidelines, 249; Comparison of Decision-Making Diagrams, 250 CONCLUSIONS AND RECOMMENDATIONS. General Conclusions, 254 Physics and Chemistry, 256 Biological Effects, 257 Toxicity of Dispersants, 257; Toxicity of Dispersed Oils, 259; Biodegradation, 260 Ecological Effects, 260 Birds and Mammals, 262 Techniques, Logistics, and Contingency Planning, 263 REFERENCES . . APPENDIXES A. Dispersant Products Information B. Case Studies . . C. Conversion Factors. GLOSSARY AND ACRONYMS. INDEX xv ....254 ..... 265 .. .309 317 322 . .324 .327

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While major oil spills are rare, oil slicks can have disastrous environmental and economic consequences. This book summarizes research on the use of chemical dispersants: their effectiveness and limitations and the results of using them in different spill situations. Based on laboratory and field research as well as on actual case histories, this book contains a clear-cut set of recommendations for action, planning, and research. Of special interest is the chapter on the biological effects of oil itself and of oil treated with chemical dispersants.

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