Oil Spill Science and Technology [1 ed.] 1856179435, 9781856179430

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Oil Spill Science and Technology

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Oil Spill Science and Technology Prevention, Response, and Cleanup

Edited by

Mervin Fingas

Amsterdam l Boston l Heidelberg l London l New York l Oxford Paris l San Diego l San Francisco l Singapore l Sydney l Tokyo Gulf Professional Publishing is an imprint of Elsevier

Gulf Professional Publishing is an imprint of Elsevier 30 Corporate Drive, Suite 400, Burlington, MA 01803, USA The Boulevard, Langford Lane, Kidlington, Oxford, OX5 1GB, UK Copyright Ó 2011 Elsevier Inc. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions. This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein). Notices Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility. To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein. Library of Congress Cataloging in Publication Data Oil spill science and technology : prevention, response, and clean up / edited by Mervin Fingas. – 1st ed. p. cm. Summary: “The National Academy of Sciences estimate that 1.7 to 8.8 million tons of oil are released into world’s water every year, of which more than 70% is directly related to human activities. The effects of these spills are all too apparent: dead wildlife, oil covered marshlands and contaminated water chief among them. This reference will provide scientists, engineers and practitioners with the latest methods use for identify and eliminating spills before they occur and develop the best available techniques, equipment and materials for dealing with oil spills in every environment. Topics covered include: spill dynamics and behaviour, spill treating agents, and cleanup techniques such as: in situ burning, mechanical containment or recovery, chemical and biological methods and physical methods are used to clean up shorelines. Also included are the fate and effects of oil spills and means to assess damage”– Provided by publisher. ISBN 978-1-85617-943-0 1. Oil spills–Prevention. 2. Oil spills–Cleanup. 3. Oil spils–Managements. I. Fingas, Mervin F. TD427.P4O38785 2010 628.1’6833–dc22 2010033465 British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library. ISBN: 978-1-85617-943-0 For information on all Gulf Professional Publishing publications visit our Web site at www.elsevierdirect.com

11 12 13 10 9 8 7 6 5 4 3 2 1 Printed and bound in the USA

Contents

Preface About the Contributors

xxv xxvii

Part I Introduction and the Oil Spill Problem 1.

2.

Introduction

3

Merv Fingas 1.1. Introduction 1.2. A Word on the Frequency of Spills

3 4

Spill Occurrences: A World Overview

7

Dagmar Schmidt-Etkin 2.1. Introduction 2.2. Executive Summary 2.3. Overview of Spill Occurrences 2.3.1. Natural Oil Seepage 2.3.2. Historical Concern Over Oil Pollution 2.3.3. Sources of Oil Spills and Patterns of Spillage 2.3.4. Spillage from Oil Exploration and Production Activities 2.3.5. Spills During Oil Transport 2.3.6. Spillage from Oil Refining 2.3.7. Spillage Related to Oil Consumption and Usage 2.3.8. Oil Inputs from Potentially Polluting Sunken Shipwrecks 2.3.9. Summary of Oil Spillage References

7 8 8 8 11 12 17 23 28 32 39 41 46

Part II Types of Oils and Their Properties 3.

Introduction to Oil Chemistry and Properties

51

Merv Fingas 3.1. Introduction

51

v

vi

Contents

3.2. The Composition of Oil 3.3. Properties of Oil References

51 54 59

Part III Oil Analysis and Remote Sensing 4.

5.

Measurement of Oil Physical Properties

63

Bruce Hollebone 4.1. Introduction 4.2. Bulk Properties of Crude Oil and Fuel Products 4.2.1. Density and API Gravity 4.2.2. Dynamic Viscosity 4.2.3. Surface and Interfacial Tensions 4.2.4. Flash Point 4.2.5. Pour Point 4.2.6. Sulphur Content 4.2.7. Water Content 4.2.8. Evaluation of the Stability of Emulsions Formed from Brine and Oils and Oil Products 4.2.9. Evaluation of the Relative Dispersability of Oil and Oil Products 4.2.10. Adhesion to Stainless Steel 4.3. Hydrocarbon Groups 4.4. Quality Assurance and Control 4.5. Effects of Evaporative Weathering on Oil Bulk Properties 4.5.1. Weathering 4.5.2. Preparing Evaporated (Weathered) Samples of Oils 4.5.3. Quantifying Equation(s) for Predicting Evaporation References Appendix 4.1

71 72 73 77 78 78 79 81 83 85

Introduction to Oil Chemical Analysis

87

Merv Fingas 5.1. Introduction 5.2. Sampling and Laboratory Analysis 5.2.1. Incorrect and Obsolete Methods 5.3. Chromatography 5.3.1. Introduction to Gas Chromatography 5.3.2. Methodology 5.4. Identification and Forensic Analysis 5.4.1. Biomarkers 5.4.2. Sesquiterpanes and Diamondoids 5.5. Field Analysis References

63 63 66 67 67 69 70 70 70 71

87 87 88 89 89 93 96 99 105 107 107

Contents

6.

Oil Spill Remote Sensing: A Review Merv Fingas and Carl E. Brown 6.1. Introduction 6.2. Visible Indications of Oil 6.3. Optical Sensors 6.3.1. Visible 6.3.2. Infrared 6.3.3. Ultraviolet 6.4. Laser Fluorosensors 6.5. Microwave Sensors 6.5.1. Radiometers 6.5.2. Radar 6.5.3. Microwave Scatterometers 6.5.4. Surface Wave Radars 6.5.5. Interferometric Radar 6.6. Slick Thickness Determination 6.6.1. Visual Thickness Indications 6.6.2. Slick Thickness Relationships in Remote Sensors 6.6.3. Specific Thickness Sensors 6.7. Acoustic Systems 6.8. Integrated Airborne Sensor Systems 6.9. Satellite Remote Sensing 6.10. Oil Under Ice Detection 6.11. Underwater Detection and Tracking 6.12. Small Remote-Controlled Aircraft 6.13. Real-Time Displays and Printers 6.14. Routine Surveillance 6.15. Future Trends 6.16. Recommendations Acknowledgments References

7.

vii 111 111 112 114 114 120 123 123 124 124 125 134 135 135 135 135 136 138 139 139 140 144 145 149 150 150 153 154 158 158

Laser Fluorosensors

171

Carl E. Brown 7.1. Principles of Operation 7.1.1. Active versus Passive Sensors 7.1.2. Sensor Features 7.1.3. Pros/Cons 7.2. Oil Classification 7.2.1. Real-Time Analysis 7.2.2. Sensor Outputs 7.3. Existing Operational Units 7.3.1. Airborne 7.3.2. Ship-Borne 7.4. Aircraft Requirements 7.4.1. Power

171 171 171 174 175 175 176 179 179 179 180 180

viii

Contents

7.4.2. Weight 7.4.3. Operational Altitude 7.5. Cost Estimates 7.6. Conclusions References

181 181 182 182 182

Part IV Behaviour of Oil in the Environment and Spill Modeling 8.

9.

Introduction to Spill Modeling

187

Merv Fingas 8.1. Introduction 8.2. An Overview of Weathering 8.2.1. Evaporation 8.2.2. Emulsification 8.2.3. Natural Dispersion 8.2.4. Dissolution 8.2.5. Photo-Oxidation 8.2.6. Sedimentation, Adhesion to Surfaces, and Oil-Fines Interaction 8.2.7. Biodegradation 8.2.8. Sinking and Overwashing 8.2.9. Formation of Tarballs 8.3. Movement of Oil and Oil Spill Modeling 8.3.1. Spreading 8.3.2. Movement of Oil Slicks 8.3.3. Spill Modeling References

192 193 194 195 196 196 197 198 199

Evaporation Modeling

201

Merv Fingas 9.1. Introduction 9.2. Review of Theoretical Concepts 9.3. Development of New Diffusion-Regulated Models 9.3.1. Wind Experiments 9.3.2. Evaporation Rate and Area 9.3.3. Study of Mass and Evaporation Rate 9.3.4. Study of the Evaporation of Pure Hydrocarbonsdwith and Without Wind 9.3.5. Other Factors 9.3.6. Temperature Variation and Generic Equations Using Distillation Data 9.3.7. A Simplified Means of Estimation 9.4. Complexities to the Diffusion-Regulated Model 9.4.1. Thickness of the Oil

187 187 188 190 191 192 192

201 205 212 212 215 215 216 217 217 227 229 229

Contents

9.4.2. The Bottle Effect 9.4.3. Skinning 9.4.4. Rises from the 0-Wind Values 9.5. Use of Evaporation Equations in Spill Models 9.6. Comparison of Model Approaches 9.7. Summary References

10.

11.

ix 229 230 233 233 235 240 241

Models for Water-in-Oil Emulsion Formation

243

Merv Fingas 10.1. Introduction 10.2. Early Modeling of Emulsification 10.3. First Two Model Developments 10.4. New Model Development 10.5. Development of an Emulsion Kinetics Estimator 10.6. Discussion 10.7. Conclusions References

243 249 251 253 260 260 269 270

Oil Spill Trajectory Forecasting Uncertainty and Emergency Response

275

Debra 11.1. 11.2. 11.3.

Simecek-Beatty Introduction: The Importance of Forecast Uncertainty The Basics of Oil Spill Modeling Trajectory Model Uncertainties 11.3.1. Release Details 11.3.2. Wind 11.3.3. Current 11.3.4. Turbulent Diffusion 11.3.5. Oil Weathering 11.3.6. Ensemble Forecasting 11.3.7. Communicating Trajectory Forecast Uncertainty 11.4. Trajectory Forecast Verification 11.4.1. Diagnostic Verification 11.5. Summary and Conclusions Acknowledgments References

275 276 280 281 282 284 287 288 289 291 292 294 295 297 297

Part V Physical Spill Countermeasures on Water 12.

Physical Spill Countermeasures

303

Merv Fingas 12.1. Containment on Water

303

x

13.

Contents

12.1.1. Types of Booms and Their Construction 12.1.2. Uses of Booms 12.1.3. Boom Failures 12.1.4. Ancillary Equipment 12.1.5. Sorbent Booms and Barriers 12.1.6. Special-Purpose Booms 12.2. Skimmers 12.2.1. Oleophilic Surface Skimmers 12.2.2. Weir Skimmers 12.2.3. Suction or Vacuum Skimmers 12.2.4. Elevating Skimmers 12.2.5. Submersion Skimmers 12.2.6. Skimmer Performance 12.2.7. Special-Purpose Ships 12.3. Sorbents 12.4. Manual Recovery 12.5. Temporary Storage 12.6. Pumps 12.6.1. Performance of Pumps 12.7. Separation 12.8. Disposal Acknowledgments References

303 306 309 313 314 314 315 316 320 321 322 323 323 325 325 329 330 332 334 334 335 337 337

Weather Effects on Oil Spill Countermeasures

339

Merv Fingas 13.1. Introduction 13.1.1. Spreading Compared to Weathering 13.1.2. Important Components of Weather 13.1.3. Oil Properties Regardless of Weathering 13.2. Review of Literature on Spill Countermeasures and Weather 13.2.1. A Priori Decision Guides 13.2.2. General Countermeasures 13.2.3. Booms 13.2.4. Skimmers 13.2.5. Dispersants 13.2.6. In-Situ Burning 13.2.7. Others 13.2.8. Ice Conditions 13.3. Development of Models for Effectiveness of Countermeasures 13.3.1. Overall 13.3.2. Booms 13.3.3. Skimmers 13.3.4. Dispersants 13.3.5. In-Situ Burning

339 340 340 343 343 343 345 345 353 372 378 381 381 383 383 383 383 398 403

Contents

13.3.6. Others 13.4. Overview of Weather Limitations 13.5. Summary and Conclusions Acknowledgments References

xi 404 405 407 416 416

Part VI Treating Agents 14.

15.

Spill-Treating Agents

429

Merv Fingas 14.1. Introduction 14.2. Dispersants 14.3. Surface-Washing Agents 14.4. Emulsion Breakers and Inhibitors 14.5. Recovery Enhancers 14.6. Solidifiers 14.7. Sinking Agents 14.8. Biodegradation Agents

429 429 430 430 431 431 431 432

Oil Spill Dispersants: A Technical Summary

435

Merv Fingas 15.1. Introduction 15.1.1. What Are Dispersants? 15.2. The Basic Physics and Chemistry of Dispersants 15.2.1. Formulations 15.2.2. Nature of Surfactant Interaction with Oil 15.3. The Basic Nature of Dispersions or Oil-in-Water Emulsions 15.3.1. Forces of Destabilization 15.3.2. The Science of Stabilization 15.3.3. Oil Spill Dispersions 15.3.4. Significance of Emulsion Stability 15.4. Effectiveness 15.4.1. Introduction to Effectiveness 15.4.2. Field Trials 15.4.3. Laboratory Tests 15.4.4. Tank Tests 15.4.5. Analytical Means 15.5. Monitoring 15.5.1. Introduction to Monitoring 15.5.2. Review of SMART Protocol 15.5.3. The SERVS Protocol 15.5.4. Review of Other Protocols 15.5.5. Review of Goodman Analysis of SMART 15.5.6. Considerations for Monitoring in the Field

435 437 437 437 438 440 441 443 447 449 451 452 454 464 467 480 481 481 482 483 486 487 488

xii

Contents

15.5.7. 15.5.8. 15.5.9. 15.5.10. 15.5.11. 15.5.12. 15.5.13. 15.5.14. 15.5.15. 15.6.

15.7.

15.8. 15.9.

15.10.

Visual Surveillance Remote Sensing Tracking of Oil on Surface Tracking of Oil Underwater Mass Balance Use of Undispersed Slick(s) as a Control Background Levels of Hydrocarbons Using and Computing Values Recommended Procedures for Monitoring Dispersant Applications Studies Energy Composition of Oil Amount of Dispersant Temperature Salinity Particle or Droplet Size

Physical 15.6.1. 15.6.2. 15.6.3. 15.6.4. 15.6.5. 15.6.6. Toxicity 15.7.1. Toxicity of Dispersants 15.7.2. Photoenhanced Toxicity 15.7.3. Testing Protocols Biodegradation Other Information 15.9.1. Component Separation 15.9.2. Dispersant Use 15.9.3. Application of Dispersants 15.9.4. Assessment of the Use of Dispersants 15.9.5. Spills-of-Opportunity Research 15.9.6. Interaction with Sediment Particles 15.9.7. Modeling Oil and Dispersed Oil Behavior and Fate 15.9.8. Separation of Dispersants from Water 15.9.9. Dispersant Breakthrough Oil Slicks 15.9.10. Overall Effects of Weather on Dispersion 15.9.11. Joint Effect of Temperature and Salinity on Effectiveness 15.9.12. Dispersibility of Biodiesels 15.9.13. Application Systems 15.9.14. Accelerated Weathering Summary and Conclusions 15.10.1. Effectiveness Testing Overall 15.10.2. Laboratory Effectiveness Tests 15.10.3. Tank Testing 15.10.4. Analytical Methods for Effectiveness 15.10.5. Toxicity of Dispersed Oil and Dispersants 15.10.6. Biodegradation of Oil Treated by Dispersants

492 493 494 494 494 495 495 496 496 500 500 506 512 512 513 519 519 532 533 534 535 539 539 539 551 553 555 555 556 557 557 557 558 559 560 560 562 563 563 564 564 564 565

xiii

Contents

15.10.7. 15.10.8. 15.10.9. 15.10.10. 15.10.11. 15.10.12. 15.10.13. 15.10.14. Acknowledgments References

16.

Spill-of-Opportunity Research 565 Monitoring Dispersant Applications 565 Dispersant Use in Recent Times 566 Interaction with Sediment Particles 566 Stability of Dispersions and Resurfacing with Time 566 Fate of Dispersed Oil 566 Application Technology and Issues 566 Correlation of Oil Properties with Effectiveness 566 566 567

A Practical Guide to Chemical Dispersion for Oil Spills Merv Fingas 16.1. Introduction and Decision Making 16.1.1. An OverviewdHow, When, and Where Dispersants Are Used 16.1.2. Net Environmental Benefit Analysis 16.1.3. Scenarios For Which Dispersants Might Be Used 16.1.4. Planning Process and Checklists 16.2. How Dispersants Are Used 16.2.1. Dispersion Spray Equipment 16.2.2. Spray Aircraft 16.2.3. Spray Nomograms and Calculations 16.2.4. Monitoring, Sampling, and Analytical Equipment 16.2.5. Equipment Availability 16.2.6. Equipment Checklist 16.2.7. Conducting the Operation 16.3. Safety and Postdispersion Actions 16.3.1. Worker Health and Safety Precautions 16.3.2. Follow-Up Monitoring Additional Information Appendix A. Specific Spill Scenarios and Dispersion Strategies Appendix B. Nomograms to Calculate Spreading and Viscosity with Time

17.

583 583 584 587 589 589 591 592 593 594 596 596 597 597 598 598 599 601 603 605

Procedures for the Testing and Approval of Oil Spill Treatment Products in the United Kingdomd What They Are and Considerations for Development

611

Mark Kirby 17.1. Background and Introduction 17.1.1. Preassessment Requirements 17.2. Toxicity Testing Procedures

611 612 613

xiv

18.

Contents

17.2.1. Reference Oil 17.2.2. Test water 17.2.3. The Sea Test 17.3. Test Description 17.3.1. The Rocky Shore Test 17.3.2. Rationale 17.3.3. Test Species 17.3.4. Test Description 17.3.5. Test Validity and Pass/Fail Assessment 17.4. Testing with Heavy Fuel Oils 17.5. The 2007 UK Scheme Review 17.5.1. Review and Improvement 17.5.2. Specific Issues 17.6. Conclusions References

613 613 615 615 616 617 618 618 619 619 620 620 620 626 627

Formulation Changes in Oil Spill Dispersants: Are They Toxicologically Significant?

629

Mark F. Kirby, Paula Neall, Jennifer Rooke, and Heather Yardley 18.1. Introduction 18.2. Materials and Methods 18.2.1. General Approach 18.2.2. Dispersants and Constituents 18.2.3. Toxicity Tests 18.2.4. Testing Schedule 18.3. Results 18.3.1. Inherent Toxicity of Constituent Chemicals and Dispersants 18.3.2. Toxicity of Reformulated Dispersants in the Sea Test 18.3.3. Toxicity of Reformulated Dispersants in the Rocky Shore Test 18.3.4. Inherent Toxicity of Reformulated Dispersants 18.4. Discussion 18.4.1. Do Formulation Changes Matter? 18.4.2. Sea Test 18.4.3. Rocky Shore Test 18.4.4. Are Specific Constituents of Concern? 18.4.5. Significance of Inherent Toxicity Changes of Formulations? Acknowledgments References

19.

Environment Canada’s Methods for Assessing Oil Spill Treating Agents Carl E. Brown, Ben Fieldhouse, Trevor C. Lumley, Patrick Lambert and Bruce P. Hollebone

629 630 630 631 631 633 633 633 634 635 635 638 638 639 639 640 641 641 642

643

Contents

19.1. 19.2.

20.

21.

xv

Introduction Toxicity and Effectiveness of Treating Agents for Oil Spills 19.2.1. Dispersants 19.2.2. Shoreline-Washing Agents 19.2.3. Deemulsifiers and Emulsion Inhibitors 19.2.4. Herding Agents 19.2.5. Recovery Agents 19.2.6. Solidifiers and Gelling Agents 19.2.7. Biodegradation Agents 19.2.8. Sinking Agents 19.3. Approval for Use of Treating Agents in Canadian Waters 19.4. Challenges to Current Toxicity Test Protocols 19.4.1. Endocrine Disrupting Capacity 19.4.2. Genotoxicity 19.4.3. Sublethal Effects 19.5. Conclusions References

662 662 664 664 665 666 667

The United States Environmental Protection Agency: National Oil and Hazardous Substances Pollution Contingency Plan, Subpart J Product Schedule (40 Code of Federal Regulations 300.900)

673

643 645 645 653 657 658 658 658 659 661

William J. Nichols 20.1. Introduction 20.2. Why Is There a Product Schedule? 20.3. Authorities for a Product Schedule 20.4. Information Requested from Manufacturers 20.5. Agency Activities 20.6. Practical Utility of the Data 20.7. Authorities for Use 20.8. Federal Agencies’ Role within the Regional Response Team 20.9. Does Listing Mean the Environmental Protection Agency Approves and Endorses a Product? 20.10. Conclusions 20.10.1. Proper Uses and Lessons Learned References

681 681 682 682

Surface-Washing Agents or Beach Cleaners

683

Merv Fingas and Ben Fieldhouse 21.1. Introduction to Surface-Washing Agents

683

673 674 675 675 679 679 680 680

xvi

22.

Contents

21.1.1. Motivations for Using Surface-Washing Agents 21.1.2. Surface Washing Agent Issues 21.1.3. Surface-Washing Agent Chemistry 21.2. Review of Major Surface-Washing Agent Issues 21.2.1. Effectiveness 21.2.2. Toxicity 21.3. Other Issues 21.3.1. Application 21.3.2. Dispersion with Higher Applied Energy 21.3.3. Assessment of the Use of Surface-Washing Agents References Appendix 21.1. Environment Canada’s Test Method Summary Method EPA Draft Protocol Summary Fieldhouse High-Energy Protocol

685 685 686 686 686 697 697 697 700 700 704 707 707 707 709 709 709

Review of Solidifiers

713

Merv Fingas and Ben Fieldhouse 22.1. Introduction to Solidifiers 22.1.1. Motivations for Using Solidifiers 22.1.2. Solidifier Issues 22.1.3. Solidifier Chemistry 22.2. Review of Major Solidifier Issues 22.2.1. Effectiveness 22.2.2. Toxicity 22.2.3. Biodegradation 22.3. Other Issues 22.3.1. Spill Size 22.3.2. Solidifier Use in Recent Times 22.3.3. Solidifiers or Sorbents 22.3.4. Potential for Sinking 22.3.5. Modeling Solidifier and Solidified Oil Behavior and Fate 22.3.6. Solidified Oil Stability 22.3.7. Fate of Unreacted Solidifier 22.3.8. Recovery of Solidified Oil 22.3.9. Solidification Time 22.3.10. Application Systems 22.3.11. Reduction of Flash Point 22.3.12. Assessment of the Use of Solidifiers 22.3.13. Disposal Methods or Recycling 22.4. Summary Acknowledgments References

713 713 714 714 717 717 728 728 728 728 729 729 729 729 729 729 729 730 730 730 730 730 730 731 731

Contents

Appendix 22.1. Testing Procedures from Environment Canada Solidifier Test Procedures Used in Early Years Oil Solidifier Effectiveness Test Used 1998 to Present Brief Description of the Test Equipment and Supplies Procedure Calculation

xvii 732 732 732 733 733 733 733

Part VII In-Situ Burning 23.

An Overview of In-Situ Burning 737 Merv Fingas 23.1. Introduction 737 23.2. An Overview of In-Situ Burning 737 23.2.1. The Science of Burning 737 23.2.2. Summary of In-Situ Burning Research and Trials 743 23.2.3. How Burns at Sea Are Conducted 750 23.2.4. Advantages and Disadvantages 755 23.2.5. Comparison of Burning to Other Response Measures 756 23.3. Assessment of Feasibility of Burning 758 23.3.1. Burn Evaluation Process 758 23.3.2. Areas Where Burning May Be Prohibited 758 23.3.3. Regulatory Approvals 763 23.3.4. Environmental and Health Concerns 765 23.3.5. Oil Properties and Conditions 793 23.3.6. Weather and Ambient Conditions 799 23.3.7. Burning in Special Locations 801 23.3.8. Burning on Land 806 23.3.9. Burning In or On Ice 809 23.4. EquipmentdSelection, Deployment, and Operation 811 23.4.1. Burning Without Containment 811 23.4.2. Oil Containment and Diversion Methods 814 23.4.3. Ignition Devices 834 23.4.4. Treating Agents 849 23.4.5. Support Vessels/Aircraft for At-Sea Burns 851 23.4.6. Monitoring, Sampling, and Analytical Equipment 852 23.4.7. Final Recovery of Residue 856 23.4.8. Equipment Checklist 858 23.5. Possible Spill Situations 858 23.6. Post-Burn Actions 870 23.6.1. Follow-Up Monitoring 870 23.6.2. Estimation of Burn Efficiency 873 23.6.3. Burn Rate 877 23.7. Health and Safety Precautions during Burning 878

xviii

Contents

23.7.1. Worker Health and Safety Precautions 23.7.2. Public Health and Safety Precautions 23.7.3. Establishing Safety Zones 23.7.4. Monitoring Burn Emissions Acknowledgments References

878 887 888 888 894 894

Part VIII Shoreline Countermeasures 24.

25.

Shoreline Countermeasures

907

Edward H. Owens 24.1. Introduction 24.1.1. Control At or Near the Source 24.1.2. Control on Water 24.1.3. Shoreline Protection Strategy 24.1.4. Shoreline Treatment 24.2. Shoreline Treatment Decision Process 24.3. Treatment Options 24.3.1. Natural Recovery 24.3.2. Physical Removal 24.3.3. In-Situ Treatment 24.4. Treatment by Shore Type 24.5. Waste Generation References

907 908 908 909 909 910 912 912 913 915 916 919 920

Automated Assessment and Data Management

923

Alain Lamarche 25.1. Introduction 25.2. Automated Processing and Data Management: Goals and Definition 25.2.1. Understanding the Use of Shoreline Assessment Data During a Response 25.2.2. The Nature of Shoreline Assessment Data 25.2.3. Practical Use of Shoreline Observations 25.3. Shoreline Observations Data Processing 25.3.1. Data Processing Organization 25.3.2. Responsibilities of the Shoreline Assessment Data Management Team 25.3.3. Data Management Tasks and Processes 25.3.4. Why and When to Establish a Shoreline Assessment Data Management Team 25.4. Assessment Automation Methods and Tools 25.4.1. Basic Tools 25.4.2. Combining Tools Within a Data Management Support System

923 924 924 924 927 929 929 931 935 939 939 940 944

xix

Contents

25.4.3. Information Distribution Shoreline Assessment Data Management Issues 25.5.1. Equipment Failure 25.5.2. Software Corruption 25.5.3. Overwhelming Amounts of Data 25.5.4. Conditions Unique to the Response References 25.5.

947 948 948 949 949 949 955

Part IX Submerged Oil 26.

Submerged Oil Jacqueline Michel 26.1. Introduction 26.2. Submerged Oil Characteristics 26.3. Review of Recent Submerged Oil Spills 26.3.1. M/V Athos I 26.3.2. T/B DBL-152 26.3.3. Lake Wabamun Spill 26.4. Submerged Oil Spill Response Methods and Recommendations for Future Work 26.4.1. Methods for Detection of Oil Suspended in the Water Column 26.4.2. Methods for Detection of Oil on the Bottom 26.4.3. Containment of Suspended Oil/Protection of Water Intakes 26.4.4. Containment of Submerged Oil on the Bottom 26.4.5. Recovery of Submerged Oil on the Bottom References

959 959 961 965 965 967 972 975 975 976 978 979 979 981

Part X Effects of Oil in the Environment 27.

Effects of Oil in the Environment Gary 27.1. 27.2. 27.3. 27.4. 27.5. 27.6. 27.7. 27.8. 27.9. 27.10. 27.11.

Shigenaka Introduction Some Definitions Size Matters: Seeps vs. Spills An “Equation” to Convey Toxic Impact Route of Exposure: The Anthrax Example Route of Exposure: Oil Oil Chemistry, Physical Behavior, and Oil Effects Freshwater/Saltwater Differences Tropical Environments Arctic Environments Ecological Effects of Oil Spills

985 985 987 989 991 999 1000 1003 1008 1010 1013 1014

xx

Contents

27.12. The Future of Oil Effects Science 27.13. Summary and Conclusions Acknowledgments Disclaimer References

1017 1019 1019 1019 1020

Part XI Contingency Planning and Command 28.

29.

Introduction to Oil Spill Contingency Planning and Response Initiation

1027

Merv Fingas 28.1. An Overview of Response to Oil Spills 28.2. Activation of Contingency Plans 28.3. Training 28.4. Structure of Response Organizations 28.5. Oil Spill Cooperatives 28.6. Private and Government Response Organizations

1027 1028 1029 1030 1030 1031

The Role of the International Tanker Owners Pollution Federation Limited

1033

Karen Purnell

30.

Safety Issues at Spills

1037

Quek Qiuhui 30.1. Introduction 30.2. Organization Structure 30.3. Health and Safety Risk Analysis/Risk Assessment 30.4. Air Monitoring 30.5. Site Safety and Health Plan 30.6. Different Types of Hazards on Site 30.7. Recommended Safety Procedures 30.7.1. Site Evaluation Process 30.7.2. Site Control Measures 30.7.3. Personal Protective Equipment 30.7.4. Excessive Noise 30.7.5. Heat Stress 30.7.6. Cold Stress 30.7.7. Monitoring Program 30.8. Emergency Procedures During a Response 30.8.1. Fire and Explosion 30.8.2. Hazardous Atmosphere/Hazardous Chemicals 30.8.3. Medical Emergencies 30.9. Other Issues

1037 1037 1038 1038 1043 1048 1049 1049 1050 1052 1052 1052 1054 1054 1054 1054 1058 1058 1059

Contents

30.9.1. Personnel Training 30.9.2. Volunteers 30.10. Conclusion Acknowledgments References

xxi 1059 1059 1062 1062 1062

Part XII Postassessment and Restoration 31.

32.

Natural Resource Damage Assessment

1067

Gary S. Mauseth and Heather Parker 31.1. Introduction 31.2. Regulatory Regimes 31.3. Objectives 31.4. Making the Public Whole 31.4.1. Injury Assessment 31.4.2. Interpretation of Restoration or Reinstatement 31.5. Alternative Sites 31.6. Use of Models 31.7. The NRDA Process in the United States 31.7.1. DOI CERCLA NRDA Regulations 31.7.2. NOAA NRDA Regulations Acronyms References

1067 1067 1069 1070 1071 1072 1075 1076 1077 1078 1079 1081 1082

Seafood Safety and Oil Spills

1083

Greg Challenger and Gary Mauseth 32.1. Introduction 32.2. Seafood Exposure to Oil 32.3. Spill Response and Seafood Safety Management 32.4. Seafood Safety Assessment: Reopening a Closed Fishery 32.5. Chemical Analytical Evaluation 32.6. Seafood Sensory Evaluation 32.7. Trends in Lifting Fishery Bans 32.8. Long-Term Implications of Oil Spills on Seafood References

1083 1085 1087 1090 1090 1092 1096 1098 1099

Part XIII Specific Case Studies 33.

The Torrey Canyon Oil Spill, 1967

1103

Robin J. Law 33.1. Case Study References

1103 1105

xxii

34.

35.

36.

Contents

The Ekofisk Bravo Blowout, 1977

1107

Robin J. Law 34.1. Case Study References

1107 1108

The Sea Empress Oil Spill, 1996

1109

Robin J. Law 35.1. Introduction 35.2. Mechanical Recovery at Sea 35.3. Dispersant Spraying at Sea 35.4. Shoreline Cleanup 35.5. Dispersant Use on Beaches 35.6. Impacts on Seabirds 35.7. Mortalities of Fish and Shellfish 35.8. Effects on Fish and Shellfish Stocks and Plankton 35.9. Contamination of Fish and Shellfish 35.9.1. Finfish 35.9.2. Crustacea 35.9.3. Whelks 35.9.4. Bivalve Mollusks 35.10. Removal of Fishery Restrictions 35.11. Conclusion References

1109 1110 1111 1112 1113 1113 1113 1114 1114 1114 1115 1115 1115 1115 1116 1116

The Braer Oil Spill, 1993

1119

Robin 36.1. 36.2. 36.3. 36.4.

37.

J. Law and Colin F. Moffat Introduction At-Sea and Shoreline Response Fate of the Braer Oil Impacts of the Braer Oil 36.4.1. On Land 36.4.2. On Seabirds 36.4.3. On Otters and Seals 36.4.4. On Commercial Fish and Shellfish 36.4.5. On Farmed Salmon 36.4.6. On Benthic Communities 36.4.7. On the Human Population 36.5. Conclusion References

1119 1119 1121 1121 1121 1121 1121 1123 1124 1125 1125 1125 1126

1991 Gulf War Oil Spill

1127

Jacqueline Michel 37.1. Review of the Spill References

1127 1131

Contents

38.

xxiii

Tanker SOLAR 1 Oil Spill, Guimaras, Philippines: Impacts and Response Challenges

1133

Ruth Yender and Katharina Stanzel 38.1. Incident Summary 38.2. Impact Summary 38.3. Shoreline Cleanup 38.4. Mangrove Cleanup and Recovery 38.5. Fisheries Impacts and Health Concerns 38.6. Summary Disclaimer References

1133 1134 1139 1143 1144 1145 1146 1146

Conversions Index

1147 1149

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Preface

Oil spill studies continue to evolve. While there are few books on the topic, there are regular conferences and symposiums which provide updates. This is the first book on the topic of oil spills for some time. As such, this book focuses on providing material that is more practical and somewhat introductory. While every attempt was made to include the essential material, there may be some gaps. The importance of many sub-topics changes with time and current spill situations. All material in this book, including introductions have been peer reviewed by at least two persons. The following peer reviewers are acknowledged (in alphabetical order): Carl Brown, Phil Campagna, Francois Charbonneau, Dagmar Schmidt Etkin, Ken Doe, Eric Gundlach, Kurt Hansen, Mike Kirby, Debra French McCay, Hugh Parker, Roger Percy, Karen Purnell, Doug Reimer, Gary Sergy, Debra Simecek-Beatty, Heidi Stout, Jordan Stout, Zhendi Wang, and Chun Yang. A special thanks goes out to the following reviewers who reviewed several papers (again in alphabetical order): Fred Beech, Leigh de Haven, Ben Fieldhouse, Anita George-Ares, Ron Goodman, Peter Lane, Robin Law, Bill Lehr, Jacqui Michel, and William Nichols. A special thanks goes out to the authors, many of whom put in their own time to complete their chapters. Their names appear throughout the text. Following this forward, I have a brief biography of each of them. I would also like to thank the many people who provided support and encouragement throughout this project, especially Meibing. I also thank Environment Canada and my former colleagues for their help and support. Environment Canada is acknowledged for permission to use materials and photos from my former employment.

xxv

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About the Contributors

Carl Brown Dr. Carl E. Brown is the Manager of the Emergencies Science and Technology Section, in the Water Science and Technology Directorate of Environment Canada. Dr. Brown has a doctorate degree in Physical Chemistry from McMaster University and a BSc in Laboratory Science from Ryerson Polytechnical University. Prior to joining Environment Canada, Dr. Brown was a research scientist on a Natural Sciences and Engineering Research Council (NSERC) Industrial Fellowship with Intera Information Technologies (now Intermap). Dr. Brown has post-doctoral experience as a research associate with the Organic Reaction Dynamics and the Laser Chemistry Groups at the Steacie Institute for Molecular Sciences, at the National Research Council of Canada and held a Canadian Government Laboratory Visiting Fellowship in Chemistry, with the Laser Chemistry Group, Division of Chemistry, National Research Council of Canada in Ottawa. His specialities include airborne oil spill sensor development, and the application of laser technologies to environmental problems. He has authored over 180 scientific papers and publications. Dr. Brown is the Chemical Science Cluster Leader for the CRTI (Chemical, Biological, Radiological, Nuclear, and Explosives Research and Technology Initiative) Program lead by Defence Research and Development Canada (DRDC) and Public Safety Canada. Dr. Brown was one of 24 scientists who recently completed the inaugural Scientists as Leaders program. Greg Challenger Greg Challenger is a Principal Marine Scientist for Polaris Applied Sciences, Incorporated in Seattle, Washington, U.S.A. Mr. Challenger is a marine ecologist by training and is involved in scientific support for oil spill and ship grounding response, natural resource injury assessment and development of habitat restoration programs. He has been a lead investigator for nearly 50 large vessel groundings, oil spills, and wreck removal operations in the Western Atlantic, Caribbean Sea, and Indo-Pacific Oceans. Dagmar Etkin Dagmar Schmidt Etkin has 35 years of experience in environmental analysis e 14 years investigating issues in population biology and ecological systems, and 21 years specializing in the analysis of oil spills. For the past 10 years, she has been president of Environmental Research Consulting (ERC), focusing on providing regulatory agencies and industry with sound scientific data and perspectives for responsible environmental decision-making. Dr. Etkin has a BA from University of Rochester, and M.A. and PhD from Harvard University. She is a member of the American Salvage

xxvii

xxviii

About the Contributors

Association, Maritime Law Association, and the UN Joint Group of Experts on the Scientific Aspects of Marine Protection. Merv Fingas Merv Fingas is a scientist focussing on oil and chemical spills. He was a spill researcher in Environment Canada for over 30 years and is currently working privately in Western Canada. Mr. Fingas has a PhD in Environmental Physics from McGill University, three masters degrees; Chemistry, Business, and Mathematics, all from University of Ottawa. His specialities include: spill dynamics and behaviour, spill treating agent studies, remote sensing and detection, and in-situ burning. He has over 750 papers and publications in the field. Dr. Fingas has been editor of the Journal of Hazardous Materials for 6 years. He has served on two committees on the U.S. National Academy of Sciences on oil spills including the recent ‘Oil in the Sea’. He is chairman of several ASTM and inter-governmental committees on spill matters. Bruce Hollebone Bruce Hollebone is a chemist with 14 years experience in the field of chemical and oil spill research and development. He has a PhD in Chemistry from the University of British Colombia. His research interests include: the fate and behaviour of oil and petroleum products in the environment, including simulation of spill behaviours in the laboratory; the development of new methods for physical and chemical analyses relevant to spills studies; environmental forensics for oil spill suspect-source identification; and environmental emergencies response. He currently works at the Oil Research Laboratory of Environment Canada. Mark Kirby Mark is an internationally recognised senior Ecotoxicologist with over 20 years experience working on studies pertaining to aquatic pollution. He has worked extensively on the toxicological impacts of oil and chemical spills and the assessment of appropriate methods of mitigation and has been involved in impact assessments in the UK from the Sea Empress to the MSC Napoli. He is a key advisor to the UK government and industry on the effects of oil and chemical spills in the marine environment and of any subsequent treatment actions (e.g. dispersants, sorbents etc.). Mark oversees the toxicological testing and approval of oil spill treatment products for use in UK waters and is the coordinator of a national initiative in the UK, PREMIAM (www.premiam.org), to implement improved post spill monitoring and impact assessment practices. He is first author of over 15 scientific papers and numerous reports in the field and continues to be actively involved in associated environmental research. Alain Lamarche Mr Lamarche is a recognized expert in spill response management systems. He has been involved in the analysis and management of environmental data since 1979. Mr. Lamarche has been responsible for the development and implementation of many computerized environmental decision support systems databases. He is also the original designer of the ShoreCleanÒ and ShoreAssess software, dedicated to the provision of Shoreline Cleanup Assessment Technique (SCAT) data management support, and

About the Contributors

xxix

Personal Digital Assistant (PDA) based geo-referenced field data acquisition tools. Mr. Lamarche has acted as a SCAT data manager and Geographical Information System (GIS) specialist during a number of oil spills, including: the Kure, New Carissa, Swanson Creek, Lake Wabamun, Westridge Line and Cosco Busan incidents. As principal of EPDS, Mr Lamarche is also responsible for all aspects of environmental software development projects including design, management, and implementation. Robin Law Robin Law is a chemist who joined Cefas (The UK Centre for Environment, Fisheries, and Aquaculture Science) in 1975. During the last 35 years he has been involved in the response and impact assessment activities following a number of major oil and chemical incidents, including the blowout on the Ekofisk Bravo platform, and from the oil tankers Amoco Cadiz, Eleni V, and Sea Empress, and the chemical tankers Ievoli Sun and Ece. Most recently, he designed and operated an environmental monitoring programme targeting oil and chemicals following the grounding of the container ship MSC Napoli on the south coast of the UK in 2007. Currently, he leads an emergency response team that advises UK government following oil and chemical spills at sea. Gary Mauseth Mr. Gary Mauseth has over 35 years of experience in the management and technical aspects of a wide variety of projects in the marine and freshwater environments. He has provided scientific support to vessel interests in over 90 spills, groundings, and natural resource damage assessment cases in the United States and its territories, as well as Canada, Mexico, the Caribbean and Mediterranean Seas, Micronesia, South America, and Europe. He has conducted research on the fate and effects of spilled oil, as well as the environmental effectiveness of response techniques, and has authored numerous publications and presentations on oil spill response, NRDA, and ecological restoration. Mr. Mauseth is a principal and President of Polaris Applied Sciences in Kirkland, Washington, USA. He has a Bachelor of Science in Biology from Whitman College in Walla Walla, Washington and a Master of Marine Biology from University of the Pacific, Pacific Marine Station, Dillon Beach, California. Jacqui Michel Dr. Jacqueline Michel is the President of Research Planning, Inc., and an internationally recognized expert in oil and hazardous materials spill planning and response. Her primary areas of expertise are in oil fates and effects, non-floating oils, shoreline cleanup, alternative response technologies, and natural resource damage assessment. Much of her expertise is derived from her role, since 1978, as part of the Scientific Support Team to the U.S. Coast Guard provided by the National Oceanic and Atmospheric Administration (NOAA). Under this role, she is on 24-hour call and provides technical support for 50-100 spill events per year. She leads shoreline assessment teams and assists in selecting cleanup methods to minimize the environmental impacts of the spill. She has evaluated and used a wide range of alternative response technologies, including surface washing agents, solidifiers, bioremediation

xxx

About the Contributors

agents, in-situ burning (mostly on wetlands and inland habitats), and methods to track and recover non-floating oils. William Nichols William (Nick) Nichols was born in Baltimore, Maryland and now lives in Ellicott City, Maryland. He has a Bachelor’s in Economics \Geography from Salisbury State University, Salisbury, Maryland and a Masters of Environmental Science from Johns Hopkins University, Baltimore. He has been an environmental scientist in the U.S. Environmental Protection Agency Office of Emergency Management (OEM) from 1997 and was U.S. National Contingency Plan Product Schedule Manager from 1998 to 2006. He is the national expert on chemical and biological oil spill countermeasures. He is also the OEM Tribal Coordinator from 2004 to the present. Ed Owens Dr. Owens is recognized internationally as an expert on oil spill shoreline cleanup and has worked on spill-related projects in the Arctic, North-South America, Africa, Russia, the Caspian, Australia, throughout South America, and in the Middle East. He has over 40 years experience providing technical and scientific support on oil response operations worldwide including: T/V Arrow (Canada), Hasbah 6 blowout (Arabian Gulf), T/V Exxon Valdez (USA), Arabian Gulf/Desert Storm (Bahrain, Qatar), Komineft pipeline (Russia), M/V Iron Baron (Australia), T/V Estrella Pampeana (Argentina), Desaguadero River (Bolivia), and M/V Cosco Busan spill (USA). Dr. Owens has conducted oil spill related missions as a United Nations Expert Consultant for the International Maritime Organization and as a consultant for the World Bank and the European Bank of Reconstruction and Development, and was a member of the U.S. National Academy of Science Oil Spill R&D Committee. Karen Purnell Dr Karen Purnell has been Managing Director of ITOPF since May 2009. She is a graduate of the Royal Society of Chemistry, with a PhD in Chemical Physics. Before joining ITOPF as a technical adviser in 1994, she worked on toxic waste management and environmental remediation in the nuclear industry and as a research chemist at several universities. Whilst at ITOPF, she has attended several major oil spills, including the sea empress (UK, 1996), prestige (Spain, 2002), and tasman spirit (Pakistan, 2003). Prominent amongst Karen’s achievements is the expansion of ITOPF’s capability to respond to spills of HNS (Hazardous & Noxious Substances). She has also worked closely with key U.S. agencies and the International Group of P&I Clubs on environmental issues. Dr Purnell has established a constructive dialogue with shipowners and is highly respected in the maritime community. Qiuhui Quek Qiuhui Quek holds a Bachelor’s degree in Environmental Engineering and has attended a number of responses in Australia, India, Indonesia, Korea, Libya, and Singapore. She has also delivered several workshops for Oil Spill Response members in various countries in the region. Qiuhui recently completed a secondment in Southampton as part of the Duty Manager rotation program. She also presented papers in international conferences such

About the Contributors

xxxi

as IOSC, Interspill, and SPE. Qiuhui has since left Oil Spill Response and is working in the HSE Management Unit of A)STAR Research Institutes. Gary Shigenaka Gary Shigenaka is the lead marine biologist with the Emergency Response Division (ERD) of the NOAA, based in Seattle. Gary received both his bachelor of science and masters degrees from the University of Washington in Seattle. As a graduate student, he served as a Knauss Sea Grant Policy Fellow in Washington D.C., and was awarded the Donald L. McKernan prize for outstanding marine affairs thesis. He has provided biological and shoreline assessment support during spills of oil and hazardous chemicals across the country and internationally over the last two decades. Gary was part of the early scientific mobilization for the Exxon Valdez oil spill in 1989, and continues to monitor the long-term effects in Prince William Sound. He also oversees other research initiatives for NOAA/ERD designed to improve oil spill impact understanding, and also to develop and improve biological tools for response and assessment. He has published numerous articles on the science and applied aspects of his spill-related research. Debra Simecek-Beatty Debra Simecek-Beatty has been a physical scientist for the NOAA’s Emergency Response Division for 25 years. She has a Masters degree in Marine Affairs from the University of Washington. During an emergency response, she is responsible for providing estimates of the movement and behavior of the spill. This includes collecting visual observations, remote sensing information, wind and current data, and computer modeling output to form an analysis. In addition, she is responsible for interfacing with local experts (i.e., meteorologist, academia, researchers) in formulating the trajectory analysis. Ruth Yender Ruth Yender is a marine ecologist with NOAA’s Office of Response and Restoration, based in Seattle, Washington. As NOAA’s Scientific Support Coordinator for the U.S. Pacific Northwest and Pacific Islands regions, Ruth provides remote and on-scene support to the U.S. Coast Guard during responses to oil and hazardous materials spills. Since joining NOAA in 1992, she has responded to more than 100 oil and chemical spills in the U.S. and internationally. Ruth also participates in spill response planning, conducts training for responders, and writes response technical guides.

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Part I

Introduction and the Oil Spill Problem

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Chapter 1

Introduction Merv Fingas

Chapter Outline 1.1. Introduction 1.2. A Word on the Frequency of Spills

3 4

1.1. INTRODUCTION Major oil spills attract the attention of both the public and the media. In past years, this attention created a global awareness of the risks of oil spills and the damage they do to the environment. In recent years, there have been fewer major spill incidents, as noted by Dagmar Etkin in Chapter 2. The public usually becomes aware of major spills, but generally does not recognize that spills are a daily fact of life. Oil is a necessity in our industrial society and a major element of our lifestyle. Most of the energy used in much of the developed world is for transportation that runs on oil and petroleum products. As current energy usage trends show, this situation is not likely to change much in the future. Industry uses oil and petroleum derivatives to manufacture such vital products as plastics, fertilizers, and chemical feedstocks, all of which will continue to be required in the future. In fact, production and consumption of oil and petroleum products are increasing worldwide, and the risk of oil pollution is increasing accordingly. The movement of petroleum from the oil fields to the consumer involves as many as 10 to 15 transfers between many different modes of transportation, including tankers, pipelines, railcars, and tank trucks. Oil is stored at transfer points and at terminals and refineries along the route. Accidents can occur during any of these transportation steps or storage times. Fortunately, in the past few years the actual number of spills has decreased. Obviously, an important part of protecting the environment is ensuring that there are as few spills as possible. Both government and industry are working to reduce the risk of oil spills by introducing strict new legislation and stringent operating codes. Industry has invoked new operating and maintenance Oil Spill Science and Technology. DOI: 10.1016/B978-1-85617-943-0.10001-2 Copyright Ó 2011 Elsevier Inc. All rights reserved.

3

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Introduction and the Oil Spill Problem

procedures to reduce accidents that lead to spills. Intensive training programs have been developed to reduce the potential for human error. Despite these measures, spill experts estimate that 30 to 50% of oil spills are either directly or indirectly caused by human error, with 20 to 40% of these incidents caused by equipment failure or malfunction. There are also many deterrents to oil spills, including government fines, loss of reputation, and high cleanup costs. In Canada, it costs an average of $20 to clean up each liter (about 1/4 gallon) of oil spilled. In the United States, these costs average about $100 per liter spilled, whereas the average cost of cleanup worldwide ranges from $20 to $200 per liter, depending on the type of oil and where it is spilled. Cleaning up oil on shorelines is usually the most expensive cleanup process.

1.2. A WORD ON THE FREQUENCY OF SPILLS Smaller oil spills are a frequent occurrence in the world, particularly because of the heavy use of oil and petroleum products in our daily lives. Canada uses about 260,000 tons of these products every day; the United States uses about 10 times this amount, and, worldwide, about 10 million tons are used per day. Most domestic oil production in Canada comes from approximately 350,000 oil wells in Alberta and Saskatchewan. There are 22 oil refineries in Canada, 5 of which are classified as large. Canada imports about 100,000 tons of crude oil or other products per day but exports about 600,000 tons per day, mostly to the United States. In the United States, more than half of the approximately 3 million tons of oil and petroleum products used daily is imported, primarily from Canada, Africa, Saudi Arabia, and other Arabic countries. About 40% of the daily demand in the United States is for automotive gasoline, and about 15% is for diesel fuel used in transportation. About 40% of the energy used in the United States comes from petroleum, 35% from natural gas, and 24% from coal. Spill statistics are collected by a number of agencies around the world. In Canada, provincial offices collect data, and Environment Canada maintains a database of spills. In the United States, the Coast Guard handles a database of spills into navigable waters, while state agencies keep statistics on spills on land which are sometimes gathered into national statistics. The Minerals Management Service (MMS) in the United States maintains records of spills from offshore exploration and production activities. It can sometimes be misleading to compare oil spill statistics, however, because different countries use different methods to collect the data. In general, statistics on oil spills are not easily obtainable, and any data set should be viewed with caution. Determining or estimating the spill volume or amount is the most difficult aspect of data collection. For example, in the case of a vessel accident, the exact volume in a given compartment may be known before the accident, but the remaining oil may have been transferred to other ships

Chapter | 1

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5

immediately after the accident. Some spill accident data banks do not include the amounts burned, if and when that occurs, whereas others include all the oil lost by whatever means. Sometimes the exact character or physical properties of the oil lost are not known, thereby leading to different estimates of the amount lost. Spill data are often collected for purposes other than future improvement of the spill response. Reporting procedures vary in different jurisdictions and organizations, such as government or private companies. Minimum spill amounts that must be reported according to federal regulations in Canada and the United States vary from 400 to 8,000 liters (100 to 2000 gals), depending on the product spilled. Spill statistics compiled in the past are less reliable than those based on more recent data because few agencies or individuals collected spill statistics before about 1975. Today, although techniques for collecting statistics are continually being improved, the resources allocated for this purpose have been reduced. The number of spills reported also depends on the minimum size or volume of the spill. In both Canada and the United States, most oil spills reported total more than 4000 L (about 1000 gals). In Canada, about 12 such oil spills take place every day, of which only about one of these spills is into navigable waters. These 12 spills amount to about 40 tons of oil or petroleum product. In the United States, there are about 25 spills per day into navigable waters and an estimated 75 spills on land. Despite the apparently large number of spills, only a small percentage of oil used in the world is actually spilled. There are proportionately more spills into navigable waters in the United States than in Canada because more oil is imported by sea and more fuel is transported by barge. In fact, the largest volume of oil spilled in U.S. waters comes from barges, while the largest number of spills is from vessels other than tankers, bulk carriers, or freighters. In Canada, most spills take place on land, and this accounts for a high volume of oil spilled. Pipeline spills account for the highest volume of oil spilled. In terms of the actual number of spills, most oil spills happen at petroleum production facilities, wells, production collection facilities, and battery sites. On water, the greatest volume of oil spilled comes from marine or refinery terminals, although the largest number of spills is from the same source as in the United Statesdvessels other than tankers, bulk carriers, or freighters. The public has the wide misconception that oil spills from tankers are the primary source of oil pollution in the marine environment. Although some of the large spills are indeed from tankers, these spills still make up less than about 5% of all oil pollution on the seas. The sheer volume of oil spilled from tankers and the high profile given these incidents in the media have contributed to this misconception. In fact, as stated earlier, half of the oil spilled in the seas is the runoff of oil and fuel from land-based sources rather than from accidental spills. In conclusion, it is important to study spill incidents from the past to learn how the oil has affected the environment, what cleanup techniques work, and what improvements can be made, as well as to identify the gaps in technology.

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Chapter 2

Spill Occurrences: A World Overview Dagmar Schmidt-Etkin

Chapter Outline 2.1. Introduction 2.2. Executive Summary

7 8

2.3. Overview of Spill Occurrences

8

2.1. INTRODUCTION Asked to picture an oil spill, most people envision a large tank ship (tanker) grounded on a large rock or reef after having gone off-course in a storm or due to navigational errors. Depending on one’s frame of reference and nationality, this might be the Exxon Valdez incident, the Hebei Spirit spill, or perhaps the Prestige spill. Oil-coated beaches, dead birds, angry fishermen, and massive cleanup efforts complete the picture. Although these types of “catastrophic” spill incidents do indeed occur occasionally and receive considerable media coverage, they are, fortunately, relatively rare events. Much more commonly, oil spills are much smaller in scope. On any given day, hundreds, if not thousands, of spills are likely to occur worldwide in many different types of environments, on land, at sea, and in inland freshwater systems. The spills are coming from the various parts of the oil industrydfrom oil exploration and production activities, from transport of that oil by tank ships, pipelines, and railroad tankcars to the refineries, and from the refineries where the oil is refined to create the many types of fuels that are then transported by pipeline, rail, truck, or tank vessel to the consumers of that oil. Consumption-related spillage comes from manufacturing facilities, nontank vessels that carry oil only as fuel and for machinery, tanker trucks bringing oils to service stations and heating oil tanks, and many miscellaneous sources. The spills occur because of structural failures, operational errors, weather-related Oil Spill Science and Technology. DOI: 10.1016/B978-1-85617-943-0.10002-4 Copyright Ó D.S. Etkin 2011.

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Introduction and the Oil Spill Problem

events, earthquakes, human errors and negligence, and even vandalism or terrorism. The spills involve many different types of oil ranging from various types of crude oil to a large array of refined products, from heavy persistent fuels to lighter, less persistent, but very toxic lighter fuels. Because each spill occurs in a different location under different circumstances of oil type and volume, proximity to sensitive resources, season, weather effects, and currents, each spill is a relatively unique event in terms of impacts, damages, and response challenges.

2.2. EXECUTIVE SUMMARY Worldwide oil spillage rates have decreased dramatically since the 1960s and 1970s, from about 635,000 tons annually to about 300,000 tons per year from all sources, not counting the anomalous intentional spillage associated with the 1991 Gulf War, which amounted to over 82 million tons on land and at sea. The largest sources of oil spills in the last two decades have been related to oil transportation by tank ships (tankers) or through pipelines. Oil inputs from spills and other chronic discharge sources, such as urban runoff, refinery effluents, and vessel operational discharges, currently total about 1.2 million tons worldwide annually. While most spills are relatively small and cause localized impacts, occasionally very large spills occur that cause significant environmental and socioeconomic damages. Despite significant progress in reducing spillage through a variety of technological and regulatory prevention measures along with better industry practices, the risk for significant oil spills remains. A more detailed analysis of oil spillage in the United States, for which there are more accurate data than many other parts of the world, reveals that during the decade of 1998e2007, inland pipelines spilled an average of nearly 11,000 tons annually, with the next largest source being refineries, which spilled 1,700 tons. Inland tanker truck spills amounted to 1,300 tons annually. Tank ships only spilled an average of 500 tons annually during this decade. Nevertheless, the risk for large spills from tank ships, facilities, and offshore oil exploration and production, all of which contain large volumes of oil, remains a concern for contingency planners and spill responders.

2.3. OVERVIEW OF SPILL OCCURRENCES 2.3.1. Natural Oil Seepage Oil slicks on water and oiled shorelines are not new phenomena. A considerable amount of crude oil is discharged each year from “natural seeps”dnatural springs from which liquid and gaseous hydrocarbons (hydrogen-carbon compounds) leak out of the ground. Oil seeps are fed by natural underground

Chapter | 2

Spill Occurrences: A World Overview

9

accumulations of oil and natural gas. Oil from submarine (and inland subterranean) oil reservoirs comes to the surface each year, as it has for millions of years due to geological processes. Natural discharges of petroleum from submarine seeps have been recorded throughout history going back to the writings of Herodotus1 and Marco Polo.2 Archaeological studies have shown that products of oil seeps were used by Native American groups living in California, including the Yokuts, Chumash, Achomawi, and Maidu tribes, well before the arrival of European settlers.3 In recent times, the locations of natural seeps have been used for exploration purposes to determine feasible locations for oil extraction. Regional assessments of natural seepage have been conducted in some locations, particularly nearshore in California,4-7 the Indian Ocean,8-10 and the Gulf of Mexico.11 The most comprehensive worldwide assessment of natural seepage is still the study conducted by Wilson et al.12 Even the two more recent international assessments of oil inputs into the sea13 relied heavily on the estimates of natural oil seepage conducted by Wilson et al.,12 having found no more recent comprehensive studies. While industry studies have been conducted for the purpose of determining potential locations for oil exploration and production using various forms of increasingly sophisticated technology, no results have been openly published in the scientific or technical literature. Natural seeps are of such great magnitude that, according to the prominent geologists Kvenvolden and Cooper,14 “natural oil seeps may be the single most important source of oil that enters the ocean, exceeding each of the various sources of crude oil that enters the ocean through its exploitation by humankind.” Assessments of natural oil seepage involve few actual measurements, though certain seep locations along the Southern California coast of the Pacific Ocean have been studied to some extent. Natural seep studies have also included identification of hydrothermically sourced hydrocarbons (especially polycyclic aromatic hydrocarbons) in sediments. The most well-known studies have relied on estimation methodologies based on field data, observations, and various basic assumptions. Wilson et al. estimated that total worldwide natural seepage ranged from 0.2 to 6.0  106 tonsy annually, with the best estimate being 0.6  106 tons, based largely on observations of seepage rates off California and western Canada.12 Estimates of the areas of ocean with natural seeps are shown in Table 2.1, and estimates of seepage rates by ocean are shown in Table 2.2. y

Oil measurements are in metric tons (tons). Within the industry, oil is often measured in barrels (equivalent of 42 U.S. gallons or 159 liters), roughly equal to one-seventh of a ton, depending on specific gravity. Conversion between tons (weight) and barrels (volume) is per the formula: tons ¼ 0.173  barrels  specific gravity.

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Introduction and the Oil Spill Problem

TABLE 2.1 Seepage-prone Areas of the World’s Oceans (based on Wilson et al.12) Number of 1,000 Square Kilometers

Ocean

High-potential Seepage

Moderate-potential Seepage

Low-potential Seepage

Pacific

1,943

9,285

4,244

Atlantic

1,303

10,363

11,248

Indian

496

7,928

3,010

Arctic

0

5,636

2,456

Southern

0

486

458

3,741

33,697

21,416

Total

Wilson et al. based their estimates on five basic assumptions: More seeps exist in offshore basins than have been observed; factors that determine seepage rates in a particular area are related to general geological structural type and stage of sedimentary basin evolution; seepage is dependent on the area of exposed rock rather than on rock volume; most marine seeps are clustered at continental margins; and seepage rates are lognormally distributed.12

TABLE 2.2 Summary of World Seepage Rates (based on Wilson et al.12) Estimated Oil Seepage (106 tons per year) Ocean

Case I, P16z

Case II, P1.0x

Case III, P0.3**

Pacific

2.83  106

2.69  105

0.689  105

Atlantic

2.06  106

1.96  105

5.04  104

Indian

9.30  105

8.85  104

2.28  104

Arctic

2.14  105

2.30  103

5.20  103

Southern

1.88  104

1.74  103

4.51  102

Total

6.05 3 106

0.558 3 105

0.148 3 106

Probability percentile 16 with a worldwide estimate of 6  106 tons annually, likely a high estimate. Probability percentile 1.0 with a worldwide estimate of 0.6  106 tons annually. **Probability percentile 0.3 with a worldwide estimate of 0.2  106 tons annually, likely a minimal estimate. z x

Chapter | 2

Spill Occurrences: A World Overview

11

Kvenvolden and Harbaugh15 concluded that the minimal worldwide estimate (0.2  106 tons annually) from the Wilson et al.12 study is most likely correct and that an error margin of an order of magnitude above and below this value should be applied (i.e., 0.02  106 to 2.0  106 tons annually). Their theory was based on a reduced value for the assumed and known oil resources that would be available for seepage. There is some evidence that seepage rates are decreasing in some locations, such as those near Coal Point, off Santa Barbara, California.16 In a 2003 National Research Council (NRC) study, a worldwide estimate of natural seepage into the marine environment of between 0.02  106 to 2.0  106 tons annually was made, with a “best estimate” of 600,000 tons.17 These estimates were made based on the Kvenvolden and Harbaugh15 reassessment of the estimates made by Wilson et al.,12 as well as an acceptance of the original estimates of Wilson et al.,12 resulting from a “new appreciation” for the magnitude of natural seepage, particularly in the Gulf of Mexico. Relying largely on the Wilson et al.12 and Kvenvolden and Harbaugh15 studies, the 2007 Joint Group of Experts on Scientific Aspects of Marine Protection (known as GESAMP) study on oil inputs into the marine environment included an estimate of the range of natural seepage as 0.2 2.0  106 tons per year, with a best estimate of 600,000 tons per year.13 Natural seeps often release oil sporadically in relatively small amounts, but occasionally release larger amounts that can have the same environmental impacts as crude oil spills from tankers or other sources. But while natural seeps have had impacts on the marine and terrestrial environment since prehistoric times, it was not until the occurrence of several larger anthropogenic oil spills in the late 1960s, which coincided with a greater public awareness of general environmental issues, that concern over oil pollution came to the forefront.

2.3.2. Historical Concern Over Oil Pollution When the tanker Torrey Canyon spilled 130,000 tons of crude oil off the western coast of the UK in March 1967, killing 15,000 seabirds and oiling nearly 300 kilometers of English and French coastline, there was a large public outcry. The environmental damage from this spill was multiplied by the use of highly toxic first-generation dispersant chemicals in the response. The Torrey Canyon spill was not the first oil tanker spill by any means. A large number of oil tankers were torpedoed and sunk during World War II. According to Campbell et al., during the first six months of 1942 alone, a total of 484,200 tons of oil were released from torpedoed tankers within 90 kilometers of the eastern U.S. coast.18 This came to about one tanker spill of about 20,000 tons per week over six months. Cleanup efforts consisted of burning incidental to the torpedoing and minimal cosmetic actions on swimming beaches. While the occurrence of these incidents during wartime may explain the

12

PART | I

Introduction and the Oil Spill Problem

relatively low concern about environmental damage from the spilled oil, there was, arguably, a general lesser awareness of environmental protection in these times as well. The Torrey Canyon spill in 1967 was notable in that when it occurred, it is the largest spill to date. The tanker’s capacity had recently been increased to hold 130,000 tons of oil cargo. Subsequently, there were at least five significantly larger worst-case discharge (complete cargo loss) tanker spills, as well as several other large spills associated with oil wells and pipelines. Following on the 1967 Torrey Canyon incident, the 1969 Union Alpha Well 21 blowout off Santa Barbara, California, which released 14,300 tons of crude oil, is often credited with being the impetus for the environmental movement in the United States, as well as for the establishment of the federal Environmental Protection Agency (EPA).19 In the 1970s, other significant oil spills around the world brought greater attention to the problem on an international scaledthe tanker Metula (Chile in 1974), the tanker Urquiola (Spain in 1977), the tanker Amoco Cadiz (France in 1978), the largest tanker spill of all time, Atlantic Empress (Trinidad and Tobago/Barbados in 1979), and the largest nonewar-related spill in historydthe Ixtoc I well blowout (Gulf of Mexico in 1979).20 The largest oil spills in history are listed in Table 2.3. The 1989 tanker Exxon Valdez spill in Alaska is perhaps the most notorious spill incident, though it is by no means the largest. The spillage of over 37,000 tons of Alaskan crude oil into what was considered to be a “pristine” location, Prince William Sound, precipitated the most expensive and the lengthiest spill response and damage settlements in history. Its repercussions were felt worldwide, resulting in the passage of significant spill prevention and liability legislation in the United Statesdthe Oil Pollution Act of 1990 (OPA 90)das well as international conventions on spill prevention that included such measures as the requirement for double-hulls on tankers by 2015 and increased financial liability. The significant financial consequences for tanker owners and operators as a result of the Exxon Valdez spill and the spiller liability inherent in subsequent regulations brought the consequences for spills to an unprecedented level. The financial risk associated with large spills may have had as much impact on spill prevention as any actual preventive measures, such as double-hulls on tankers.

2.3.3. Sources of Oil Spills and Patterns of Spillage Spills occur around the worlddanywhere that oil is produced, transported, stored, or consumed. The vast majority of spills are relatively small. As shown in Figure 2.1, 72% of spills are 0.003 to 0.03 ton or less. The total of amount of these small spills comes to 0.4% of the total spillage. The largest spills (over 30 tons) make up 0.1% of incidents but involve nearly 60% of the total amount spilled. Naturally, the relatively rare large spill incidents get the most public attention owing to their greater impact and visibility, though spill size itself is

Chapter | 2

13

Spill Occurrences: A World Overview

TABLE 2.3 Largest Oil Spills in History Worldwide Environmental Research Consulting (ERC data)** Date

Source Name*

Location

Tons

10-Mar-1991

700 oil wells

y

Kuwait

71,428,571

20-Jan-1991

Min al Ahmadi Terminalyz

Kuwait

857,143

3-Aug-2000

oil wells

Russia

700,000

3-Jun-1979

Ixtoc I well

Mexico

476,190

Iraq

377,537

Uzbekistan

299,320

Trinidad/Tobago

286,354

Russia

285,714

y

1-Feb-1991

Bahra oil fields

2-Mar-1990

oil well x

19-Jul-1979

T/V Atlantic Empress

25-Oct-1994

Kharyaga-Usinsk Pipeline y

4-Feb-1983

No. 3 Well (Nowruz)

Iran

272,109

6-Aug-1983

T/V Castillo de Bellver

South Africa

267,007

16-Mar-1978

T/V Amoco Cadiz

France

233,565

10-Nov-1988

T/V Odyssey

Canada

146,599

11-Apr-1991

T/V Haven

Italy

144,000

1-Aug-1980

D-103 concession well

Libya

142,857

6-Jan-2001

pipeline

Nigeria

142,857

Kuwait

139,690

19-Jan-1991

yz

T/V Al Qadasiyah y

19-Jan-1991

T/V Hileen

Kuwait

139,690

18-Mar-1967

T/V Torrey Canyon

United Kingdom

129,857

19-Dec-1972

T/V Sea Star

Oman

128,891

23-Feb-1980

T/V Irenes Serenade

Greece

124,490

yz

19-Jan-1991

T/V Al-Mulanabbi

Kuwait

117,239

7-Dec-1971

T/V Texaco Denmark

Belgium

107,143

19-Jan-1991

T/V Tariq Ibn Ziyadyz

Kuwait

106,325

20-Aug-1981

storage tanks

Kuwait

106,003

yz

26-Jan-1991

Min al Bakar Terminal

Kuwait

100,000

15-Nov-1979

T/V Independentza

Turkey

98,255

11-Feb-1969

T/V Julius Schindler

Portugal

96,429

(Continued )

14

PART | I

Introduction and the Oil Spill Problem

TABLE 2.3 Largest Oil Spills in History Worldwide Environmental Research Consulting (ERC data)**dcont’d Date

Source Name*

Location

12-May-1976

T/V Urquiola

Spain

95,714

25-May-1978

No. 126 Well/pipeline

Iran

95,238

28-Mar-1995

pipeline

Nigeria

90,000

5-Jan-1993

T/V Braer

United Kingdom

85,034

Kuwait

83,897

yz

Tons

1-Mar-1991

pipeline

29-Jan-1975

T/V Jakob Maersk

Portugal

82,503

6-Jul-1979

storage tank (Tank #6)

Nigeria

81,429

19-Nov-2002

T/V Prestige

Spain

77,000

3-Dec-1992

T/V Aegean Sea

Spain

74,490

6-Dec-1985

T/V Nova

Iran

72,626

15-Feb-1996

T/V Sea Empress

United Kingdom

72,361

19-Dec-1989

T/V Khark 5

Morocco

70,068

27-Feb-1971

T/V Wafra

South Africa

68,571

11-Dec-1978

fuel storage depot

Zimbabwe

68,027

26-Apr-1992

T/V Katina P.

South Africa

66,700

12-Jun-1978

Sendai Oil Refinery

Japan

60,204

6-Dec-1960

T/V Sinclair Petrolore

Brazil

60,000

7-Jan-1983

T/V Assimi

Oman

53,741

9-Nov-1974

T/V Yuyo Maru No. 10

Japan

53,571

28-May-1991

T/V ABT Summer

Angola

51,020

22-May-1965

T/V Heimvard

Japan

50,000

31-Dec-1978

T/V Andros Patria

Spain

49,660

30-Jan-1991

T/V Ain Zalah yz

Kuwait

49,543

13-Jun-1968

T/V World Glory

South Africa

48,214

13-Jan-1975

T/V British Ambassador

Japan

48,214

9-Dec-1983

T/V Pericles GC

Qatar

47,619

9-Aug-1974

T/V Metula

Chile

47,143

Chapter | 2

15

Spill Occurrences: A World Overview

TABLE 2.3 Largest Oil Spills in History Worldwide Environmental Research Consulting (ERC data)**dcont’d Date

Source Name*

Location

Tons

1-Jun-1970

T/V Ennerdale

Seychelles

46,939

7-Dec-1978

T/V Tadotsu

Indonesia

44,878

29-Feb-1968

T/V Mandoil

United States

42,857

10-Jun-1973

T/V Napier

Chile

38,571

13-Mar-1994

T/V Nassia

Turkey

38,500

26-Aug-1979

T/V Patianna

United Arab Emirates

38,000

11-Jun-1972

T/V Trader

Greece

37,500

24-Mar-1989

T/V Exxon Valdez

United States

37,415

29-Dec-1980

T/V Juan Antonio Lavalleja

Algeria

37,279

21-Oct-1994

T/V Thanassis A.

Hong Kong

37,075

22-Apr-1988

T/V Athenian Venture

Canada

36,061

7-Feb-1977

T/V Borag

Taiwan

35,357

Mar-1986

Pemex Abkatun 91

Mexico

35,286

6-Feb-1976

T/V St. Peter

Colombia

35,100

*“T/V” ¼ “tank vessel” and refers to tank ships or tankers. **Ended in January 2010. y War-related intentional spillage. z Several intentional spills occurred nearly simultaneously during the 1991 Gulf War. They are often aggregated into one large “spill.” In this list, the individual spill sources are separated. x T/V Atlantic Empress spilled 145,250 tons of oil off Trinidad and Tobago on 19 July 1979, then another 141,000 tons while under tow off Barbados.

not a direct measure of damage. Location and oil type are extremely important in determining the degree of environmental and socioeconomic damage. Oil spills and discharges* can occur at any point in the “life cycle” of petroleumdduring oil exploration and production; transport by vessel, pipeline, railroad, or tanker truck; refining; storage, consumption or usage as fuel or as raw material for manufacturing; or waste disposal. The regional and national patterns of spillage depend on the oil-related activities in those *

A “spill” is a discrete event in which oil is accidentally or, occasionally, intentionally released. A “discharge” is a legal permitted release of oil (usually in a highly diluted state in water) as part of normal operations.

16

PART | I

Introduction and the Oil Spill Problem

% Total Spills 80% 71.9%

70%

# spills

60%

amount

50% 39.5%

40% 30% 22.8%

22.2%

20.3%

20% 6.2%

10% 0%

11.7%

0.4%

0.003

1.6%

0.03

4.3%

0.3

1.6%

3

0.3%

3,000

0.1%

30

0.0%

300

Spill Size (tonnes) FIGURE 2.1 Size classes of U.S. marine oil spills, 1990e1999 (ERC data).

locations, the amount of oil handled, and the degree to which oil prevention measures have been implemented and enforced. Overall, oil spillage has decreased significantly in the United States and internationally due to the implementation and enforcement of prevention measures as well as more responsible operations on the part of the shipping and oil industries.13,17,21,22 In the 1970s, an estimated 6.3 million tons of oil spilled into marine waters from all sources, excluding war-related incidents.22 By the 1980s, an estimated 3.8 million tons of oil spilled worldwide, a 40% reduction since the decade 1988e1997. Spillage reduced another 20% by the 1990s. These reductions in spillage are all the more remarkable considering the increases in production, shipping, and handling of oil during this time period (Table 2.4). In a series of studies that estimated total oil inputs into the marine environment from spills, as well as from operational discharges* from shipping and other sources, especially urban runoff,y a definitive trend of input reduction is apparent (Table 2.5). It is important to note that some of the variations between the studies are due to differences in methodology rather than to actual differences in inputs. *

A legal permitted release of oil (usually in a highly diluted state in water) as part of normal operations. y “Urban runoff” is the accumulation of drops of oil that leak from automobiles, trucks, and other vehicles, as well as small chronic spillages that occur from other land-based sources. The oil washes off into storm sewers, culverts, and other waterways into streams and rivers that enter marine waters. Because the exact source of this spillage cannot be pinpointed, it is termed nonpoint source pollution.

Chapter | 2

17

Spill Occurrences: A World Overview

TABLE 2.4 Annual Worldwide Marine Oil Spillage (ERC Data) Estimated Average Annual Tons Spilledy Source Type

1970s

1980s

1990s

428,646

190,180

126,743

2,735

23,811

10,248

Pipelines

59,087

36,744

85,664

Facilities

66,067

58,047

35,655

Offshore Exploration/ Production

69,111

68,099

38,351

9,241

1,775

3,905

634,887

378,656

300,546

Tank Vessels Nontank Vessels

Unknown/Other Total y

Excluding war-related spills.

The tracking of oil spills is generally conducted by those authorities involved in initiating emergency spill response operations, such as Coast Guard agencies or state and local governments. The accuracy of reporting, particularly of smaller spills, varies considerably from one jurisdiction to another. There have been increases in the reporting of increasingly smaller spills, though not necessarily in the actual incidence of such spills, which reflects broader public awareness of spills and greater concern about and responsibility for these incidents by spillers. As larger spills become increasingly rarer, it is important that contingency planners and spill responders maintain preparedness for these large spills owing to the potential damages associated with them.22,23 A detailed recent overview of oil spills in the United States is presented here based on Environmental Research Consulting (ERC) data, along with analytical results from some past international studies on oil spills.24-28

2.3.4. Spillage from Oil Exploration and Production Activities During the years 1998e2007, an estimated 182 tons of crude oil spilled annually from offshore exploration and production platforms into U.S. waters. An additional 373 tons spilled annually from pipelines associated with offshore oil production, for a total of 555 tons per year. This represents a nearly 66% reduction in spillage since 1988e1997, and an 87% reduction in spillage since the 1970s (1969e1977). Oil spillage from offshore platforms in U.S. Outer Continental Shelf (OCS) and state waters is shown in Figure 2.2 for 1969e2007.

TABLE 2.5 Estimated Worldwide Oil Inputs Based on Various Studies 18

Oil Input Estimates (Tons) Source Natural Seeps Municipal/Industrial Urban Runoff Coastal Refinery Other Coastal

Tanker Accidents Other Shipping

Atmospheric

zzz

Offshore Expl/Prod TOTAL z

1981**

1981yy

1990zz

1997xx

2000***

600,000

600,000

300,000

200,000

258,500

600,000

600,000

2,700,000

2,250,000

1,480,000

1,230,000

1,175,000

114,900

156,900

2,500,000

2,100,000

1,430,000

1,080,000

e

n/a

140,000

200,000

e

e

100,000

e

112,500

4,900

e

150,000

50,000

50,000

e

2,400

12,000

2,130,000

1,100,000

1,440,000

1,420,000

564,000

389,000

413,100

300,000

300,000

390,000

400,000

e

157,900

100,000

yyy

7,100

750,000

200,000

340,000

320,000

e

586,500

1,080,000

600,000

710,000

700,000

e

225,800

306,000

600,000

600,000

300,000

300,000

305,000

68,000

24,700

80,000

60,000

50,000

50,000

47,000

19,750

38,000

10,940,000

7,960,000

6,490,000

5,850,000

2,349,500

2,246,750xxx

1,802,700

[24] [25] **[26] yy [27] zz [28] xx [13] ***[17] yyy Includes 53,000 tons from small-craft activity. zzz Atmospheric deposition of petroleum hydrocarbons from volatile organic compounds (VOCs) that evaporate during the handling of oil and incomplete fuel combustion that are then deposited into the sea. xxx Does not include urban runoff. x

Introduction and the Oil Spill Problem

Operational

1979x

PART | I

Transportation

1973z

Chapter | 2

19

Spill Occurrences: A World Overview

Tonnes 18,000 16,000 14,000 12,000 10,000 8,000 6,000 4,000 2,000 0 1969

1974

1979

1984

1989

1994

1999

2004

FIGURE 2.2 Annual U.S. offshore oil platform spillage, 1969e2007 (ERC data).

Average platform spillage by decade is shown in Table 2.6. There has been a 30% reduction in annual spillage since 1988e1997 and a 95% reduction since the 1970s. Annual oil spillage from pipelines connected to offshore platforms is shown in Figure 2.3, and by decade in Table 2.7. There has been a 68% reduction in offshore pipeline spillage since 1988e1997. Of the total spillage, 96% is in the Gulf of Mexico. Offshore oil exploration and production spillage was combined to include offshore platforms and pipelines, as well as offshore supply vessels servicing the platforms, as shown in Table 2.8. There has been a 61% reduction in total spillage since 1988e1997 and an 87% reduction since the 1970s.

TABLE 2.6 Average Annual Spillage from U.S. Offshore Oil Platforms (ERC data) Years

Average Annual Spills One Ton or More

Average Annual Tons Spilled

1969e1977

45

3,694

1978e1987

29

192

1988e1997

14

259

1998e2007

20

182

1969e2007

27

1,015

20

PART | I

Introduction and the Oil Spill Problem

Tonnes 5,000 4,500 4,000 3,500 3,000 2,500 2,000 1,500 1,000 500 0 1969

1974

1979

1984

1989

1994

1999

2004

FIGURE 2.3 Annual oil spillage from U.S. offshore pipelines, 1969e2007 (ERC data).

TABLE 2.7 Average Annual Spillage from U.S. Offshore Oil Pipelines (ERC data) Years

Average Annual Spills One Ton or More

Average Annual Tons Spilled

1969e1977

15

640

1978e1987

10

495

1988e1997

14

1,161

1998e2007

13

373

1969e2007

13

668

Oil spillage per production (i.e., barrels spilled per barrels produced) has decreased over time, as shown in Table 2.9. In other words, despite increases in production, spillage rates have decreased. For every ton of oil produced in the United States, less than 0.000005 tons have spilled from offshore exploration and production activities in the last decade. This is a 71% reduction since the 1988e1997 decade and an 87% reduction since the 1969e1977 decade. While the majority of oil production spills have been recorded in offshore waters, there are reported spills of inland-based oil production wells to inland areas, as shown in Table 2.10. During the oil extraction process at offshore oil platforms, water in the oil reservoir is also pumped to the surface. Industry practice is to treat this

Chapter | 2

21

Spill Occurrences: A World Overview

TABLE 2.8 Average Annual Spillage (tons) from U.S. Offshore Oil Activities (ERC data) Years

Platforms

Pipelines

Offshore Vessels

Total

1969e1977

3,694

640

14

4,348

1978e1987

192

495

39

726

1988e1997

259

1,161

7

1,427

1998e2007

182

373

1

556

1969e2007

1,015

668

15

1,698

TABLE 2.9 U.S. Offshore Oil Exploration/Production Spillage per Production (ERC data) Years

Average Annual Tons Spilled per Tons Produced

1969e1977

0.0000089

1978e1987

0.0000015

1988e1997

0.0000040

1998e2007

0.0000012

1969e2007

0.0000038

TABLE 2.10 Average Annual U.S. Inland Oil Exploration/Production Spillage (ERC data) Years

Average Annual Tons Spilled

1980e1987

521

1988e1997

742

1998e2004

863

1980e2004

705

“produced water” to separate free crude oil, and then to inject the water back into the reservoir, or to discharge the water overboard from the platform. Increasingly, the reinjection process is becoming the preferred technique. The highly diluted oil content in produced water (with a maximum allowable oil

22

PART | I

Introduction and the Oil Spill Problem

TABLE 2.11 Estimated Oil Inputs in Produced Water from U.S. Offshore Oil Exploration/Production

U.S. Region

Produced Water (tons/yr)

Oil/Grease Content (ppm)

Oil/Grease Discharge (tons/yr)

Low

High

“Best”*

Low

High

“Best”

Gulf of Mexico OCS

67,571,429

15

29

20

1,300

2,500

1,700

Louisiana State

26,571,429

15

29

20

450

860

600

e

e

6.6

0

0

5

Texas State

614,286

California Offshore

5,157,143

15

29

18

85

170

85

Alaska State

6,528,571

15

29

15

110

210

110

e

e

20

2,000

3,740

2,500

Total US

106,442,858

*Best estimate as determined by panel of experts in the 2003 NRC study.17

content of 29 ppm) from offshore oil exploration and production processes is generally dispersed very quickly in the open waters where offshore oil platforms are located. The impacts from these inputs in offshore waters have been studied extensively, and, as concluded by the 2003 NRC study, “there is little evidence of significant effects from petroleum around offshore platforms in deep water.”17 The oil inputs from produced water are calculated as shown in Table 2.11don average, 2,500 tons per year, based on the methodology used by the 2003 NRC study based on measurements and assumptions of maximum allowable oil content in produced water (“high”) or lower oil content as reported by offshore operators.17 It is important to note that these inputs are permitted operational discharges that are distinct from accidental spillage previously reviewed. Worldwide estimates on oil spillage and discharges from offshore oil exploration and production activities are shown in Table 2.12. The greatest concern associated with oil pollution from offshore oil and gas exploration is the unlikely event of a catastrophic well “blowout”*. The largest well blowout incidents worldwide are shown in Table 2.13. Fortunately, most blowouts release relatively little oil.29 *

Loss of well control or a blowout is defined as: the uncontrolled flow of formation or other fluids, including flow to an exposed formation (an underground blowout) or at the surface (a surface blowout), flow through a diverter, or uncontrolled flow resulting from a failure of surface equipment or procedures.

Chapter | 2

23

Spill Occurrences: A World Overview

TABLE 2.12 Worldwide Spillage and Discharge from Offshore Oil Exploration and Production Annual Oil Input Estimate (tons)

Study

Estimate Year

Spillage

Operational

Atmospheric

Total

NRC, 1975 [24]

1973

e

e

e

80,000

Kornberg, 1981 [25]

1979

e

e

e

60,000

Baker, 1983 [26]

1981

e

e

e

50,000

NRC, 1985 [27]

1981

e

e

e

50,000

GESAMP, 1993 [28]

1990

e

e

e

47,000

GESAMP, 2007 [13]

1997

3,400

16,350

e

19,750

NRC, 2003 [17]

2000

860

19,000

1,300

21,160

2.3.5. Spills During Oil Transport After extraction from offshore or terrestrial wells, oil is transported by a variety of means to refineries and ultimately to industrial or individual consumersdby tank vessel (tank ships or tankers; tank barges), pipeline, railroad, and tanker truck, each potentially a source of spillage.

2.3.5.1. Spillage from Tank Vessels Tank ships can carry the greatest amount of oildas much as 300,000 tonsdand thus can be the sources of the largest transport-related spills. Tank ships (tankers) carrying crude oil or refined petroleum as cargo spilled an average of 514 tons of oil annually in U.S. waters over the last decade, a 90% reduction since the decade 1988e1997. A breakdown of annual spillage from oil tankers is shown in Figure 2.4. Average annual spillage by decade is shown in Table 2.14. Tank barges carrying oil as cargo spilled an average of 771 tons of oil annually over the last decade, a nearly 67% reduction from the spillage in the decade 1988e1997. Annual spillage volumes are shown in Figure 2.5. A breakdown of average annual spillage from oil tank barges is shown in Table 2.15. Oil transport by tank vessels (tankers and barges) has decreased over the last decades in the United States. Oil spillage from tank vessels in the United States in relation to oil transported by this mode decreased by 71% since the decade 1988e1997 and 81% since the 1980s (Table 2.16). Worldwide estimates of tanker and tank barge spillage made in international studies are shown in Table 2.17.

24

PART | I

Introduction and the Oil Spill Problem

TABLE 2.13 Largest Offshore Exploration and Production Well Blowouts Worldwide (ERC data) Well

Location

Date

Tons

Ixtoc I

Bahia del Campeche, Mexico

June 1979

471,430

Pemex Abkatun 91

Bahia del Campeche, Mexico

October 1986

35,286

Phillips Ekofisk Bravo

North Sea, Norway

April 1977

28,912

Nigerian National Funiwa 5

Forcados, Nigeria

January 1980

28,571

Aramco Hasbah 6

Gulf, off Saudi Arabia

October 1980

15,000

Iran Marine International

Gulf, off Laban Island, Iran

December 1971

14,286

Union Alpha Well 21

Santa Barbara, California, USA

January 1969

14,286

Chevron Main Pass 41-C

Gulf of Mexico, Venice, Louisiana, USA

March 1970

9,286

Pemex Yum II/Zapoteca

Bahia del Campeche, Mexico

October 1987

8,378

Shell South Timabalier B-26

Gulf of Mexico, Bay Marchand, Louisiana, USA

December 1970

7,585

2.3.5.2. Spills from Pipelines In inland areas, underground and above-ground pipelines transport large quantities of crude oil and refined fuels, particularly diesel, gasoline, heavy fuel oil, and trans-mix.* Spillage from pipelines in coastal and inland areas is shown in Table 2.18 and Figure 2.6. During the last decade, coastal and inland pipelines spilled an average of 11,000 tons of oil annually. This represents a 35% reduction in spillage since 1988e1997 and 70% since the 1970s. In these analyses, coastal and inland pipelines were considered to encompass all parts of the pipeline system, including gathering pipes, transmission pipes, breakout tanks, pump stations, and tank farms directly associated with and operated by pipeline companies. Offshore pipelines were considered separately under *

Usually a combination of No. 2 fuel oil (diesel) and No. 6 heavy fuel oil.

Chapter | 2

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Spill Occurrences: A World Overview

Tonnes 90,000 80,000 70,000 60,000 50,000 40,000 30,000 20,000 10,000 0 1962

1967

1972

1977

1982

1987

1992

1997

2002

2007

FIGURE 2.4 Spills into U.S. waters from tank ships, 1962e2007 (ERC data).

TABLE 2.14 Average Annual Oil Spillage from Tank Ships in U.S. Waters (ERC data) Years

Average Number of Spills One Ton or More

Average Annual Tons Spilled

1962e1967

e

7,162

1968e1977

301

27,513

1978e1987

153

8,607

1988e1997

55

6,028

1998e2007

19

514

offshore exploration and production. It should be noted that a significant portion of oil (about 85%) that spills from inland pipelines goes to containment areas around breakout tanks or to solid ground rather than directly into surface waters. With concerns about the aging pipeline infrastructure and vulnerability of pipelines for spillage, there have been a number of regulatory changes for pipelinesdthe Oil Pollution Act of 1990 (OPA 90), the 2002 Pipeline Safety Act (PSA), and the 2006 Pipeline Integrity, Protection, Enforcement, and Safety (PIPES) Act, which have improved pipeline safety and reduced spillage. Pipeline spillage amounts by oil type and per unit of oil transport are shown in Table 2.19. Spillage per unit transport has decreased 37% since the decade 1988e1997, and 57% since the 1980s.

26

PART | I

Introduction and the Oil Spill Problem

Tonnes 16,000 14,000 12,000 10,000 8,000 6,000 4,000 2,000 0 1968

1973

1978

1983

1988

1993

1998

2003

FIGURE 2.5 Spills into U.S. waters from tank barges, 1968e2007 (ERC data).

TABLE 2.15 Average Annual Oil Spillage from Tank Barges in U.S. Waters (ERC data) Years

Average Number of Spills One Ton or More

Average Annual Tons Spilled

1968e1977

368

4,547

1978e1987

290

7,570

1988e1997

123

3,269

1998e2007

54

776

1968e2007

186

4,040

2.3.5.3. Spills from Railroads Railroads spilled 200 tons of oil annually as cargo in tankcars and as fuel. This is a 34% reduction since the decade 1988e1997. Average annual railroad spillage and spillage by ton-miles transported are shown in Table 2.20. (A tonmile is a measure of the transport of oil one ton the distance of one mile.) The spillage rate has decreased in the last three decades. Spills from railroads often go to ballast and do not always directly impact waterways. 2.3.5.4. Spillage from Tanker Trucks Tanker trucks carrying oil (usually fuels) as cargo spilled an average of 1,300 tons of oil annually in the last decade, a 76% increase since the decade 1988e1997.

Chapter | 2

27

Spill Occurrences: A World Overview

TABLE 2.16 Oil Spillage by Tank Vessels in Relation to Oil Transported in U.S. Waters (ERC data) Average Annual Spillage (tons) Tankers

Tank Barges

Combined

Average Annual Spillage per Billion Ton-Miles* Oil Transport

1978e1987

8,607

7,570

16,177

27.40

1988e1997

6,028

3,269

9,297

18.22

1998e2007

514

776

1,290

5.28

Time Period

*Ton-miles combine volume and distance of transport.

TABLE 2.17 Estimates of Worldwide Annual Tank Vessel Spillage Estimate of Average Annual Tank Vessel (Tank Ship and Tank Barge) Spillage (tons) Study

1970s

1980s

1990s

NRC, 1975

300,000

e

e

Kornberg, 1981

300,000

e

e

Baker, 1983

e

390,000

e

NRC, 1985

e

400,000

e

GESAMP, 1993

e

564,000*

e

GESAMP, 2007

e

e

157,900

NRC, 2003

e

e

100,000

Etkin, 2001

372,878

98,866

184,460y

ERC Data

431,381

213,991

136,991z

*Includes operational discharges from vessels. y Includes 1991 Gulf War-related tanker spillage. z Excludes 1991 Gulf War-related tanker spillage.

This may be attributed to better reporting of these incidents to local authorities that usually handle these incident responses. Spills from tanker trucks often go to pavements and do not directly impact waterways. Average annual spillage is in Table 2.21. There are no reliable international data on this source type.

28

PART | I

Introduction and the Oil Spill Problem

TABLE 2.18 Oil Spillage from U.S. Inland and Coastal Pipeline Systems (ERC data) Years

Average Annual Number of Spills One Ton or More

Average Annual Tons

1968e1977

276

37,049

1978e1987

172

25,885

1988e1997

140

16,900

1998e2007

195

10,965

1968e2007

196

22,828

Tonnes 70,000 60,000 50,000 40,000 30,000 20,000 10,000 0 1968

1974

1979

1984

1989

1994

1999

2004

FIGURE 2.6 Spills into U.S. waters from pipelines, 1968e2007 (ERC data).

2.3.6. Spillage from Oil Refining Each year, on average, over 8.6 billion tons of imported and domesticallyproduced crude oil are refined into hundreds of petroleum-based products and fuels at the 162 refineries in the United States. Spillage from oil refineries averaged 1,700 barrels annually over the last decade, about a 19% reduction since the decade 1988e1997 and a 27% reduction in spillage per barrel of oil throughput at refineries. Average annual spillage is shown in Table 2.22. The lower spillage for the 1980e1987 time period is likely a data artifact since spill sources in reports were not always accurately identified (e.g.,

Chapter | 2

29

Spill Occurrences: A World Overview

TABLE 2.19 Average Annual U.S. Oil Pipeline Spillage by Oil Type and Transport (ERC data) Tons Spilled per Billion Ton-Miles* Transport

Spillage (tons) Years

Crude

Refined

Total

Crude

Refined

Total

1980e1987

11,314

6,157

17,471

35.24

25.06

30.71

1988e1997

16,384

9,292

25,676

48.99

40.42

45.50

1998e2007

10,855

6,558

17,413

32.38

25.95

29.71

1980e2007

7,716

3,249

10,965

27.11

11.89

19.88

*A ton-mile is one ton of oil being transported one mile.

TABLE 2.20 Average Annual Estimated U.S. Oil Spillage from Railroads (ERC data) Years

Tons Spilled per Year

Tons Spilled per Billion Ton-Miles Transport

1980e1987

332

26.7

1988e1997

309

18.6

1998e2007

204

10.3

1980e2007

278

16.2

TABLE 2.21 Average Annual Estimated U.S. Oil Spillage from Tanker Trucks (ERC data) Years

Tons per Year

Tons Spilled per Billion Ton-Miles Transport

1980e1987

698

25.5

1988e1997

745

26.2

1998e2007

1,312

41.2

1980e2007

934

31.6

30

PART | I

Introduction and the Oil Spill Problem

TABLE 2.22 Average Annual Oil Spillage from U.S. Refineries (ERC data)

Years

Tons Spilled

Annual Refining Capacity (tons)

Refinery Utilization

Annual Throughput (tons)

Spillage per Refinery Throughput

1980e1987

502

9.17  109

78.95%

0.66  109

0.00000076

1988e1997

2,145

9.41  109

89.71%

0.72  109

0.00000296

1,734

9

91.62%

0.80  10

9

0.00000216

0.73  10

9

0.00000208

1998e2007 1980e2007

1,529

10.33  10

9

9.66  10

87.32%

a refinery may merely have been identified as a “facility”). There were also changes in reporting requirements in 1986 that authorized the Toxics Release Inventory (TRI) to track facility releases of a variety of chemicals and toxic substances. While crude oil and refined petroleum products themselves are not encompassed by the TRI-reporting requirements, some of their additives and chemical components are listed. Overall, this created a greater awareness of the need to report discharges from refineries. During refining, wastewater containing minute concentrations of oil is legally discharged in effluents, as permitted under the National Pollutant Discharge Elimination System (NPDES). The NPDES-permitted refinery effluents contain no more than five parts of oil per million parts of wastewater. The effluents are generally discharged in rivers and coastal areas where the already dilute oil concentrations are quickly diluted even further. The environmental impacts of refinery effluents have been studied fairly extensively. Environmental impacts from the oil in the effluents are extremely low and localized. Refineries are, however, generally located in industrial areas that have other permitted discharges, making it difficult to separate the effects of oil in effluents from those of background concentrations of other contaminants from other point and nonpoint sources. A comprehensive review of the ecological impacts of refinery effluents concluded that any minor impacts are limited to the areas close to the outfalls, but that it is difficult to distinguish these impacts from other pollution sources.30 The total amount of aqueous effluent discharged from oil refineries has decreased by 20% over the last 40 years due to increases in the use of air cooling and recirculation of cooling water. In addition, the toxicity of effluent discharges has decreased significantly owing to the implementation of various wastewater treatment systems.30,31 The estimated maximum discharge of oil in refinery effluents over the last decade is 7,700 tons per year. This estimate is the equivalent of less than 0.00001 ton of oil for each ton of oil processed, and is based on the following assumptions: wastewater production as a function of refinery capacity average for the last decade is 2.37

Chapter | 2

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Spill Occurrences: A World Overview

TABLE 2.23 Estimated Annual Oil Discharged in U.S. Oil Refinery Effluents (ERC data)

Years

Throughput (billion tons)

Wastewater Tons per Ton Throughput

Wastewater (billion bbl)

Oil in Effluent (tons)

1985e2007

0.66

2.15

1.17

5,837

1985e1987

0.72

1.69

1.49

7,465

1988e1997

0.80

2.05

1.91

9,538

1998e2007

0.73

2.38

1.55

7,740

barrels of wastewater (refinery effluent) produced per barrel of refining capacity; and effluents contain 5 ppm of oil (based on NPDES guidelines). There are a number of estimates of the amount of wastewater produced per unit of refining capacity. The average of the two best-documented sources was taken.31,32 Average annual refinery effluent discharges in the United States are shown in Table 2.23. The average annual oil in legally-permitted refinery effluent discharges is based on an assumption of maximum effluent oil concentration of 5 ppm. This value is the maximum allowed. Actual oil concentrations in effluents are likely to be lower. Estimates of international coastal refinery spillage and effluent oil content were made as shown in Table 2.24. Estimates in the 2007 GESAMP study were made using the same methodology as for U.S. refinery effluents, with the exception that the oil content in the effluent was assumed to vary between 5 ppm and 25 ppm, depending on national laws and practices.13

TABLE 2.24 Estimates of Worldwide Oil Refinery Spillage and Effluent Discharges Estimated Average Annual Inputs to Marine Waters (tons)

Study

Year(s)

Refinery Spillage

Oil in Refinery Effluent

Total Refinery Inputs

NRC, 1975

1970s

200,000

e

200,000

Baker, 1983

1980s

100,000

e

100,000

GESAMP, 2007

1990s

e

179,547

179,547

32

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Introduction and the Oil Spill Problem

2.3.7. Spillage Related to Oil Consumption and Usage Refined petroleum products are used in a wide variety of applications, including fuels for transportation, heating, manufacturing, and electricity production. Spillage of oil from sources that “consume” or use oil is generally outside of the realm of the petroleum industry itself, but is presented here for perspective on total oil inputs.

2.3.7.1. Spillage from Nontank Vessels “Nontank vessels” (e.g., cargo ships) carrying oil as bunker fuel and for operations spill an average of 230 tons of oil annually, a 43% reduction since the decade 1988e1997. Average annual spillage from these vessels is shown in Table 2.25. At the same time, the shipment of dry cargo (i.e., nonpetroleum shipments) by vessels has increased by 43% over the last 30 years in the United States (U.S. Army Corps of Engineers). The rate of spillage from these cargo ships in relation to the tonnage of cargo moved in U.S. waters during that time period is shown in Table 2.26. Spillage per cargo shipment has declined by 50% since the decade 1988e1997. Worldwide nontank vessel spillage was estimated in several international studies (Table 2.27). Spillage from smaller vessels (e.g., passenger, fishing, recreational, and unclassified vessels) averaged under 600 tons annually over the last decade in the United States, a nearly 34% reduction since the decade 1988e1997. Average annual spillage from these vessels is shown in Table 2.28. There are no reliable worldwide estimates of spillage from smaller vessels. Operational discharges of lubricant oils from the vessels within ports, during transit within ports, and while moored at docks contribute a significant amount of oil to U.S. watersdabout 2,800 tons annually.33 Leakages occur from stern tubes and other submerged machinery, as well as from on-deck

TABLE 2.25 Average Annual Oil Spillage from Nontank Vessels in U.S. Waters (ERC data) Years

Annual Number of Spills (1 ton or more)

Annual Tons Spilled

1973e1977

100

149

1978e1987

85

969

1988e1997

83

402

1998e2007

37

229

1973e2007

73

479

Chapter | 2

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Spill Occurrences: A World Overview

TABLE 2.26 Cargo Vessel Oil Spillage per Dry Cargo Shipments in U.S. Waters (ERC data) Years

Dry Cargo Shipment (million short tons)

Annual Tons Spilled

Tons Spilled per Million Short Tons Shipped

1978e1987

1,057

969

0.90

1988e1997

1,256

402

0.32

1998e2007

1,382

229

0.16

1978e2007

1,232

534

0.46

TABLE 2.27 Estimates of Worldwide Nontank Vessel Spillage Estimate of Average Annual Nontank Vessel Spillage (tons) Study

1970s

1980s

1990s

NRC, 1975

750,000*

e

e

Kornberg, 1981

200,000*

e

e

Baker, 1983

e

340,000*

e

NRC, 1985

e

320,000*

e

GESAMP, 2007

e

NRC, 2003

e

533,000* 7,100

Etkin, 2001

1,000

4,024

5,454

ERC Data

2,735

23,811

10,248

*Includes operational discharges from nontank vessels.

machinery. Based on a study by Etkin, these inputs are estimated to be as shown in Table 2.29, as calculated for the past five years.33 Previous time periods were adjusted based on the overall amount of shipping in U.S. waters. Operational inputs of oil and gasoline from two-stroke engines in the United States were estimated by the 2003 NRC study17 to average 7,000 tons annually and by the 2007 GESAMP study13 to average 53,000 tons annually worldwide (Table 2.30). It should be noted that this estimate has been questioned by a number of researchers (personal communications) with regard to the assumption that all of the gasoline enters the water rather than combusts or evaporates. The use of two-stroke engines of the type mentioned in this study has significantly decreased in the last few years.

34

PART | I

Introduction and the Oil Spill Problem

TABLE 2.28 Estimated Oil Spillage from Smaller Vessels in U.S. Waters (ERC data) Years

Annual Tons Spilled

1973e1977

2,123

1978e1987

939

1988e1997

900

1998e2007

595

1973e2007

999

TABLE 2.29 Vessel Operational Lubricant Leakage in U.S. and Worldwide Ports33 Lubricant Discharges (average annual tons) Stern Tube

Other Operational

Total

Years

U.S.

Worldwide

U.S.

Worldwide

U.S.

Worldwide

1980e1987

1,064

19,558

1,036

22,082

2,101

41,488

1988e1997

1,246

22,903

1,213

25,859

2,460

48,584

1998e2007

1,400

25,734

1,363

29,055

2,764

54,589

1980e2007

1,237

22,738

1,204

25,672

2,442

48,233

2.3.7.2. Spillage from Facilities Coastal facilities (other than refineries) spill an estimated 600 tons of oil in the United States annually, a 72% reduction from the decade 1988e1997. Average annual facility spillage in the United States and worldwide is presented in Table 2.31. It is important to note that spillage volumes from coastal facilities often include oil that spills into secondary containment. A secondary containment system provides an essential line of defense in preventing oil from spreading and reaching waterways in the event of the failure of an oil container (e.g., a storage tank) or the primary containment. The system provides temporary containment of the spilled oil until a response can be mounted. In the last decade, gas stations and truck stops spilled an average of 100 tons of oil annually, a nearly 48% decrease since the decade 1988e1997. This

Chapter | 2

Spill Occurrences: A World Overview

35

TABLE 2.30 Estimates of Oil Inputs from Two-Stroke Recreational Vessels in the United States and Worldwide Estimated Average Annual Tons Input

Region U.S. Atlantic*

3,100

U.S. Gulf of Mexico*

1,540

U.S. Pacific and Alaska*

2,306

U.S. Total*

6,946

Worldwide*

53,000

*Estimates based on analyses in the 2003 NRC study.17

TABLE 2.31 Estimated Oil Spillage from Coastal Marine Facilities in U.S. and Worldwide Waters Years

U.S. Annual Tons Spilledy

Worldwide Annual Tons Spilled

1973e1977

8,889

150,000z

1978e1987

6,112

50,000x

1988e1997

2,151

1998e2007

604

1973e2007

3,803

e 2,400*e12,000** e 13

*From 2007 GESAMP study based on methods in the 2003 NRC study.17 The 2007 GESAMP study13 had a second estimate of 3.9  106 tons annually. y ERC data z [24] x [25, 26] **[23]

includes all spillages that occur at gas station facilities and truck stops, including spills that occur during the transfer of fuels from tanker trucks. Average annual spillage from these sources is shown in Table 2.32. Spills at gas stations and truck stops often go to pavements and other substrates, reducing the direct impacts to waterways. There are no reliable estimates of worldwide spillage rates. Inland facilities regulated under the United States’ Environmental Protection Agency’s Spill Prevention, Control, and Countermeasures (SPCC) program other than refineries and production wells, covered separately in these analyses,

36

PART | I

Introduction and the Oil Spill Problem

TABLE 2.32 Estimated U.S. Oil Spillage from Gas Stations and Truck Stops (ERC data)* Year

Annual Spillage (tons)

1980e1987

171

1988e1997

223

1998e2007

116

1980e2007

170

*Based on reported data reported to the relevant state and local authorities in the 50 U.S. states, as well as data reported to federal authorities. These data do not include leaking underground storage tanks that leak over long periods of time. These data are tracked separately and are not considered emergency spill incidents. Since gas stations are regulated by the EPA, facilities spillage at these facilities of at least 50 gallons (0.17 tons) that occur during these facilities are included. Smaller spills (less than 50 gallons) are not included.

TABLE 2.33 Estimated U.S. Oil Spillage from Inland EPA-Regulated Facilities (ERC data) Years

Annual Spillage (tons)

1980e1987

4,963

1988e1997

35,002

1998e2007

8,525

1980e2007

16,963

spill an average of 8,500 tons of oil annually, a 76% reduction since the decade 1988e1997 (Table 2.33). Spills at inland facilities often go to pavements and other substrates, including secondary containments, reducing direct impacts to waterways. There are no reliable estimates of worldwide spillage rates. Oil spillage from home-heating oil tanks, which are not regulated by the EPA unless the tanks are in sizes larger than 34 tons, amounts to 70 tons of oil annually, a slight decrease from the decade 1988e1997 (Table 2.34). Note that this does not include slow leakages from underground storage tanks. There are no reliable estimates of worldwide spillage rates from residential tanks. Motor vehicles that carry oil as fuel rather than cargo spill about 285 tons of oil annually in the United States, double that for the decade 1988e1997 (Table 2.35). The spillage is associated with greater motor vehicle traffic, as well as

Chapter | 2

Spill Occurrences: A World Overview

37

TABLE 2.34 Estimated Oil Spillage from U.S. Residential Heating Oil Tanks (ERC data) Years

Annual Tons Spilled

1980e1987

26

1988e1997

74

1998e2007

71

1980e2007

59

TABLE 2.35 Estimated U.S. Oil Spillage from Motor Vehicles (excluding tanker trucks) (ERC data) Year

Annual Tons Spilled

Average 1980e1987

39

Average 1988e1997

170

Average 1998e2007

295

Average 1980e2007

168

better reporting by local authorities that are often the emergency responders. Motor vehicle spills* often go to pavements and do not directly impact waterways. Since the data only include spills of less than 1 ton, most passenger vehicles are excluded. There are no reliable estimates of worldwide spillage from motor vehicles.

2.3.7.3. Spillage from Aircraft and Other Sources Aircraft spill an estimated 50 tons of jet fuel annually to inland areas. These spills generally occur at airports during fueling, or occasionally from an accident. Aircraft spill an additional 530 tons annually to U.S. marine waters, based on a 2003 NRC study.17 These spills occur from two sources: through the deliberate discharge or jettisoning of jet fuel due to emergency conditions aboard an aircraft, or through the release of partially burned fuel in inefficient engines or operating modes.17,34 This type of spillage also occurs over inland areas, but there are no *

Note that tanker trucks carrying oil as cargo are considered separately.

38

PART | I

Introduction and the Oil Spill Problem

TABLE 2.36 Estimated U.S. Oil Spillage (bbl) from Other Inland Sources (ERC data) Years

Inland Aircraft (annual tons)

Inland Unknown (annual tons)

1980e1987

2

138

1988e1997

23

314

1998e2007

49

74

1980e2007

26

190

current estimates of these inputs. Total aircraft input in the United States is estimated to be about 580 tons of oil annually. The 2003 NRC study estimated worldwide marine inputs from jettisoned aircraft fuel to be about 7,500 tons annually.17 Average annual spillage from aircraft and miscellaneous unknown (unidentified) inland sources in the United States is shown in Table 2.36.

2.3.7.4. Oil Inputs from Urban Runoff About 50,000 tons of oil enters U.S. marine waters each year through urban runoff, based on a 2003 NRC study.17 Urban runoff is the accumulation of drops of oil that leak from automobiles, trucks, and other vehicles, as well as small chronic spillages that occur from other land-based sources. Oil washes off into storm sewers, culverts, and other waterways into streams and rivers that enter marine waters. Because the exact spillage source cannot be pinpointed, it is termed “nonpoint source” pollution. The U.S. inputs are broken down by region in Table 2.37. Studies that included worldwide estimates of oil in urban runoff are shown in Table 2.38.

TABLE 2.37 Estimates of U.S. Oil Inputs from Urban Runoff Region

Estimated Average Annual Tons of Oil Input*

Atlantic

31,500

Gulf of Mexico

12,600

Pacific

5,829

Alaska

80

Total

50,009

*Estimates based on analyses in the NRC 2003 study.17

Chapter | 2

39

Spill Occurrences: A World Overview

TABLE 2.38 Estimates of Worldwide Marine Oil Inputs from Urban Runoff Estimate of Average Annual Oil Inputs from Urban Runoff (tons) Study

1970s

1980s

1990s

NRC, 1975

2,500,000

e

e

Kornberg, 1981

2,100,000

e

e

Baker, 1983

e

1,430,000

e

NRC, 1985

e

1,080,000

e

NRC, 2003

e

e

140,000

2.3.8. Oil Inputs from Potentially Polluting Sunken Shipwrecks Potential future and documented current oil leakage and discharges from sunken ships in marine waters is an issue of concern worldwide. A study conducted in 1977 drew attention to the oil discharges from a large number of oil tankers sunk during military operations in World War II along the U.S. western, eastern, and southern (Gulf of Mexico) coasts.18 While the tankers had been sunk over 30 years earlier, oil was still periodically leaking from the vessels, which were acting as “seeps.” Many of the tankers were still relatively intact, though their structural integrity was uncertain. The issue of oil pollution from sunken World War II tankers and military vessels was further brought to public attention after several incidents of oil leaking from several vessels (notably the S.S. Jacob Luckenbach off the Pacific coast of the United States, the USS Mississinewa in Micronesia, and the German warship Blu¨cher off Oslo, Norway) in the late 1990s to 2004. These sunken vessels were identified as the sources of “mystery spills” and discharges that impacted shorelines and other resources.35 The South Pacific Environment Programme (SPREP) has conducted surveys of wrecks in the South Pacific region particularly impacted by World War II military vessel sinkings.36,37 In 2005, the American Petroleum Institute and the sponsors of the International Oil Spill Conference* commissioned a study, Potentially Polluting Wrecks in Marine Waters, which involved developing a databasey of recorded *

International Maritime Organization, U.S. Coast Guard, U.S. Environmental Protection Agency, International Petroleum Industry Environmental Conservation Association, Minerals Management Service, and National Oceanic and Atmospheric Administration.

y

The proprietary database was developed by ERC.

40

PART | I

Introduction and the Oil Spill Problem

FIGURE 2.7 Approximate location of potentially polluting shipwrecks* (ERC data).

vessel sinkings for tankships of at least 150 gross registered tons (GRTs) carrying oil and nontank vessels of at least 400 GRTs that carried oil as fuel/ bunkers (and for operations); an analysis of the distribution of and likely amount of oil contained in these vessels; and an examination of the environmental, regulatory, political, technical, and financial issues associated with these sources of petroleum.38 The data analysis revealed that there were at least 8,569 recorded vessel sinkings worldwide, of which 1,583 were tankships and 6,986 were nontank vessels. An estimated 2.5 to 20.4 million tons of oil is thought to be present in these shipwrecks. The shipwrecks are distributed throughout the world, as shown in Figure 2.7. The data in the 2005 Michel et al. study were analyzed regionally, as summarized in Table 2.39.38 This oil will not necessarily discharge, but there is the potential that it will, with the actual probability of discharge depending on vessel integrity and condition, age, depth at which the wrecks rest, temperature of the waters, and type of oil. Heavier fuels at greater depths may be nearly solid, and many of the vessels may be largely intact. On the other hand, the greatest potential for spillage is with the older vessels, particularly those from World War II, which were often built according to lower standards than more modern vessels. The potential for impacts depends largely on the location of the wrecks. Those in nearshore waters tend to present the greatest potential for impacting *

Dots indicate approximate locations based on Marsden square (10-degree latitude/longitude). Because many of the vessels are “war-graves” and there are also safety concerns, authorities aim to prevent plundering or diving exploration. The exact locations of many vessels are uncertain or are classified or confidential.

Chapter | 2

Spill Occurrences: A World Overview

41

TABLE 2.39 Worldwide Potential Pollution from Sunken Tankers and Nontank Vessels (ERC data) Estimated Oil Content of Shipwrecks (tons) Region

Minimum

Maximum

North Atlantic Ocean

951,000

7.5 million

South Atlantic Ocean

165,000

0.5 million

North Pacific Ocean

221,000

1.7 million

South Pacific Ocean

521,000

4.2 million

Indian Ocean

264,000

2.2 million

shorelines. The impacts of discharges from these vessels in the open ocean are likely to be less severe than those closer to shore because of the natural dispersion that would break the oil into smaller concentrations. Much of the oil involved is likely to be heavier and would most likely form tar balls rather than larger slicks unless released in a large mass. The experts who conducted the 2005 Michel et al. study concluded that most of the vessels were likely to release oil in small quantities over a longer period of time or had already started to do so, acting almost as a “natural seep.” Nevertheless, there is the potential for a vessel to suddenly release a much larger quantity of oil if a radical change takes place in the vessel’s structural integrity.38 The political, regulatory, and financial issues associated with these shipwrecks are extremely complex due to jurisdictional concerns. Removing the oil and other hazardous materials, as well as munitions, from these vessels involves complex, dangerous, and expensive salvage operations. It is unclear who would finance or regulate these operations, especially for the large number of World War II vessels involved. Because of the complex issues presented by these wrecks and the overwhelming number of potentially polluting wrecks, an approach involving scientifically based risk assessments and cost-benefit analyses has been promoted by several organizations, government agencies, and researchers to prioritize those wrecks that poset the highest environmental risk for oil and hazardous material removal operations.38-44

2.3.9. Summary of Oil Spillage Estimates of average annual U.S. oil spillage by decade from all source categories are summarized in Table 2.40. Over the last decade, the largest source category of spillage is inland pipelines, followed by EPA-regulated facilities. The oil spillage reported here does not reflect the amounts of oil

42

PART | I

Introduction and the Oil Spill Problem

TABLE 2.40 Estimated Total Average Annual U.S. Oil Spillage (tons) 1969e 1977

1978e 1987

1988e 1997

1998e 2007

Production

4,491

1,243

2,169

1,420

5.07%

Offshore Platform Spills

3,694

192

259

182

0.65%

640

495

1,161

373

1.33%

Offshore Supply Vessels

14

35

7

1

0.00%

Inland Production Wells

143

521

742

863

3.08%

Refining

429

502

2,145

1,734

6.19%

Refinery Spills

429

502

2,145

1,734

6.19%

Transport

69,809

43,092

27,250

13,770

49.16%

Inland Pipelines

37,049

25,885

16,900

10,965

39.15%

Tanker Trucks

429

698

745

1,312

4.68%

Railroads

286

332

309

204

0.73%

Tank Ships

27,499

8,607

6,028

514

1.83%

Tank Barges

4,547

7,570

3,269

776

2.77%

16,932

13,887

39,789

11,088

39.58%

714

969

402

229

0.82%

2,123

939

900

595

2.12%

171

171

223

116

0.41%

21

26

74

71

0.25%

4,286

4,963

35,002

8,525

30.43%

529

531

552

578

2.06%

Coastal Facilities

8,889

6,112

2,151

604

2.16%

Inland Unknown

129

138

314

74

0.26%

71

39

170

295

1.05%

91,660

58,723

71,354

28,011

100.00%

Source Type

Offshore Pipelines

Storage and Consumption Nontank Vessels Other Vessels Gas Stations and Truck Stops Residential Inland EPA-Reg Facilities* Aircrafty

Motor Vehicles Total

% Total 1998e2007

*Excludes refineries, gas stations, and production wells. Includes aircraft in inland areas plus estimates of marine inputs (based on NRC, 2003).

y

Chapter | 2

43

Spill Occurrences: A World Overview

that were contained or recovered. It also does not reflect the differences between oil that is spilled directly into marine or freshwater systems and oil that is spilled onto other surfaces, including containment areas around storage tanks in tank farms. The properties of the oil spilled (crude vs. refined, heavy vs. light) and the locations in which the oil spills (marine waters, inland waters, dry surfaces, wetlands, industrial zones) will largely determine the impacts of these spills and should be considered in addition to the actual amounts of oil spilled. Total U.S. oil inputs to marine and inland waters, including spills, runoff, and all operational discharges are shown in Table 2.41. TABLE 2.41 Estimated Total Average Annual U.S. Oil Inputs (tons) Source Type

1969e 1977

1978e 1987

1988e 1997

1998e 2007

% Total 1998e2007

Production

5,876

2,431

3,438

2,930

2.15%

Offshore Platform Spills

3,694

192

259

182

0.13%

Offshore Pipeline Spills

640

495

1,161

373

0.27%

Offshore Supply Vessel Spills

14

39

7

1

0.00%

Inland Production Well Spills

521

742

863

705

0.52%

1,007

963

1,148

1,669

1.23%

35,963

52,758

68,910

55,915

41.09%

429

502

2,145

1,734

1.27%

Refinery Effluents

35,534

52,256

66,765

54,181

39.82%

Transport

69,882

43,084

27,163

13,864

10.19%

Inland Pipelines

37,049

25,885

16,900

10,965

8.06%

Tanker Trucks

429

698

745

1,312

0.96%

Railroads

332

309

204

278

0.20%

Tank Ships

27,513

8,607

6,028

514

0.38%

Tank Barges

4,547

7,570

3,269

776

0.57%

12

15

17

19

0.01%

67,841

65,497

91,595

63,357

46.56%

Produced Water Refining Refinery Spills

Tank Vessel Operational Discharge Storage and Consumption

(Continued )

44

PART | I

Introduction and the Oil Spill Problem

TABLE 2.41 Estimated Total Average Annual U.S. Oil Inputs (tons)dcont’d Source Type Nontank Vessels

1969e 1977

1978e 1987

1988e 1997

1998e 2007

% Total 1998e2007

149

969

402

229

0.17%

Other Vessels

2,123

939

900

595

0.44%

Vessel Operational Discharge

2,000

2,086

2,443

2,745

2.02%

171

223

116

170

0.12%

21

26

74

71

0.05%

4,286

4,963

35,002

8,525

6.27%

2

2

23

49

0.04%

Coastal Facilities (Nonrefining)

8,889

6,112

2,151

604

0.44%

Inland Unknown

129

138

314

74

0.05%

71

39

170

295

0.22%

50,000

50,000

50,000

50,000

36.75%

179,562

163,770

191,106

136,066

100.00%

Gas Stations and Truck Stops Residential Inland EPA-Regulated Facilities** Aircrafty

Motor Vehicles Urban Runoff Total

**Excludes refineries, gas stations, and production wells. Includes aircraft in inland areas, plus estimates of marine inputs based on the 2003 NRC study [17].

y

Although annual spill amounts vary from year to year, often due to one or two particularly large incidents, there has been a general downward trend in U.S. spills in the past decade, and an even greater downward trend since 1989, the year of the Exxon Valdez spill (Figure 2.8). Worldwide trends are shown in Figure 2.9. The large spill in 1979 from the Ixtoc I well blowout dominates the spillage. War-related intentional spillage, such as that in the 1991 Gulf War, has not been included. Despite general downward trends in spills in the United States and worldwide, it is important that spill response preparedness be maintained due to the continuing risk of spills, including worst-case discharge scenarios. Most spills will continue to be “routine” in that they are relatively small and easily responded to with local resources. At the same time, occasional large spills, along with increasing public expectations for effective spill response and increased spiller liability, have necessitated complex contingency planning for

Chapter | 2

45

Spill Occurrences: A World Overview

Tonnes 140,000 120,000 100,000 80,000 60,000 40,000 20,000 0 1968

1973

1978

1983

1988

1993

1998

2003

FIGURE 2.8 Annual oil spillage into U.S. waters with reduction trends (ERC data).

Tonnes 2,000,000 1,800,000 1,600,000 1,400,000 1,200,000 1,000,000 800,000 600,000 400,000 200,000 0 1970

1975

1980

1985

1990

1995

2000

FIGURE 2.9 Worldwide oil spillage with reduction trends (ERC data).

increasingly rare high-impact events.22 For example, the United States with its experience in the 1989 tanker Exxon Valdez, which involved the spillage of over 37,000 tons of oil, has not experienced a worst-case discharge scenario, defined as the complete release of the contents of a fully loaded oil tanker or large storage facility. Had the Exxon Valdez released its entire contents, about five times as much oil would have spilled into Prince William Sound. The complexity of the spill response and the impact of the spill is difficult to envision, but must be planned for. The magnitude of the spill from the MC-252

46

PART | I

Introduction and the Oil Spill Problem

well (otherwise referred to as Deepwater Horizon spill) that occurred during April through July 2010 has not yet been verified, though it has been been confirmed to be the largest spill in US history.

REFERENCES 1. Lees GM, et al. The Eastern Hemisphere. In: Pratt WE, Good D, editors. World Geography of Petroleum, 159. Princeton University Press; 1950. 2. Levorson AI. Geology of Petroleum, 14. San Francisco, CA: Freeman Press; 1954. 3. Hodgson SF. Onshore Oil and Gas Seeps in California, California Division of Oil and Gas. Department of Conservation; 1987. 4. Allen A, Schlueter RS, Mikolaj PG. Natural Oil Seepage at Coal Oil Point, Santa Barbara, California. Science 1970;974. 5. Hornafius JS, Quigley D, Luyendyk BP. The World’s Most Spectacular Marine Hydrocarbon Seeps (Coal Point, Santa Barbara Channel, California): Quantification of Emissions. J. Geophys. Res 1999;703. 6. Kvenvolden KA, Simoneit BRT. Hydrothermically Derived Petroleum: Examples from Guaymas Basin, Gulf of California, and Escanaba Trough, Northeast Pacific Ocean. Amer. Assoc. Petrol. Geolog. Bull. 1990;223. 7. Leifer I, Luyendyk B, Broderick K. Tracking Seep Oil from Seabed to Sea Surface and beyond at Coal Oil Point, California, Proceedings of the American Association of Petroleum Geologists (AAPG). Salt Lake City: Utah; 2003. 8. Chernova TG, Rao PS, Pikovskii Y, Alekseeva TA, Nagender NB, Ramalingeswara RB, et al. The Composition and the Source of Hydrocarbons in Sediments Taken from the Tectonically Active Andaman Backarc Basin, Indian Ocean. Mar. Chem. 2001;1. 9. Gupta RS, Qasim SZ, Fondekar SP, Topgi RS. Dissolved Petroleum Hydrocarbons in Some Regions of the Northern Indian Ocean. Mar. Pollut. Bull. 1980;65. 10. Venkatesan MI, Ruth E, Rao PS, Nath BN, Rao BR. Hydrothermal Petroleum in the Sediments of the Andaman Backarc Basin, Indian Ocean. Appl. Geochem. 2003;845. 11. MacDonald IR. Natural Oil Spills. Scientific American 1998;57 (Nov). 12. Wilson RD, Monaghan PH, Osanik A, Price LC, Rogers MA. Natural Marine Oil Seepage. Science 1974;857. 13. GESAMP (IMO/FAO/UNESCO-IOC/UNIDO/WMO/IAEA/UN/UNEP Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection). Estimates of Oil Entering the Marine Environment from Sea-Based Activities. GESAMP Reports and Studies 2007;75. 14. Kvenvolden KA, Cooper CK. Natural Seepage of Crude Oil into the Marine Environment. Geo-Marine Letters 2003;140. 15. Kvenvolden KA, Harbaugh JW. Reassessment of the Rates at Which Oil from Natural Sources Enters the Marine Environment. Mar. Environ. Res. 1983;223. 16. Quigley DC, Hornafius JS, Luyendyk BP, Francis RD, Clark J, Washburn L. Decrease in Natural Marine Hydrocarbon Seepage near Coal Oil Point, California, Associated with Offshore Oil Production. Geology 1999;1:047. 17. National Research Council Committee on Oil in the Sea. Oil in the Sea III: Inputs, Fates, and Effects, National Research Council Ocean Studies Board and Marine Board Divisions of Earth and Life Studies and Transportation Research Board. Washington, DC: National Academy Press; 2003.

Chapter | 2

Spill Occurrences: A World Overview

47

18. Campbell B, Kern E, Horn D. Impact of Oil Spillage from World War II Tanker Sinkings, Report No. MITSG 77e4 Index No. 77-304-Nnt. Cambridge: Massachusetts Institute of Technology Sea Grant Program; 1977. 19. Easton R. Black Tide: The Santa Barbara Oil Spill and Its Consequences. New York: Delacorte Press; 1999. 20. Hayes MO. Black Tides. Austin: University of Texas Press; 1999. 21. Etkin DS. Analysis of Oil Spill Trends US and Worldwide. IOSC 2001;291. 22. Etkin DS. Analysis of Past Marine Oil Spill Rates and Trends for Future Contingency Planning. AMOP 2002;227. 23. Etkin DS. Analysis of US Oil Spill Trends to Develop Scenarios for Contingency Planning. IOSC 2003;47. 24. National Research Council. Petroleum in the Marine Environment. Washington, DC: National Academy of Sciences; 1975. 25. Kornberg H. Royal Commission on Environmental Pollution: 8th Report. London: Her Majesty’s Stationery Office; 1981. 26. Baker JM. Impact of Oil Pollution on Living Resources, Comm. Ecology Paper No. 4. Gland, Switzerland: International Union for Conservation of Nature and Natural Resources; 1983. 27. National Research Council. Oil in the Sea: Inputs, Fates, and Effects. Washington, DC: National Academy Press; 1985. 28. GESAMP (IMO/FAO/UNESCO/WMO/WHO/IAEA/UN/UNEP Joint Group of Experts on the Scientific Aspects of Marine Pollution). Impact of Oil and Related Chemicals and Wastes on the Marine Environment. GESAMP Reports and Studies 1993;Vol. 50. 29. Etkin DS. Analysis of US Oil Spillage. American Petroleum Institute Publication 356, Environmental Research Consulting; 2009. 30. Wake H. Oil Refineries: A Review of Their Ecological Impacts on the Aquatic Environment. Estuarine, Coastal and Shelf Science 2005;131. 31. CONCAWE, Trends in Oil Discharged in Aqueous Effluents from Oil Refineries in Europe: 2000 Survey, Report No. 4/04, CONCAWE (The Oil Companies’ European Association for Environmental, Health, and Safety in Refining and Distribution), Brussels, 2004. 32. American Petroleum Institute (API). Water Reuse Studies. Washington, DC: API Publication No. 949. American Petroleum Institute; 1977. 33. Etkin DS. Worldwide Analysis of In-Port Vessel Operational Lubricant Discharges and Leakages. AMOP; 2010. 34. Canadian Environmental Assessment Agency (CEAA), Military Flying Activities in Labrador and Quebec, Ottawa, 1995. 35. Symons L, Hodges MK. Undersea Pollution Threats and Trajectory Modeling. Mar. Techn, Soc. J. 2004;78. 36. Nawadra S, Gilbert TD. Risk of Marine Spills in the Pacific Island Region and Its Evolving Response Arrangements. Sydney, Australia: Proceedings of the International Spill Conference, SpilCon 2002; 2002. 37. South Pacific Regional Environment Programme (SPREP). Regional Strategy to Address Marine Pollution from World War II Shipwrecks. Majuro, Marshall Islands: Thirteenth SPREP Meetings of Officials (Item 7.2.2.1); July 2002, 21e25. 38. Michel J, Etkin DS, Gilbert T, Urban R, Waldron J, Blocksidge CT. Potentially Polluting Wrecks in Marine Waters. IOSC; 2005. 39. Etkin DS, van Rooij JAC, French-McCay D. Risk Assessment Modeling Approach for the Prioritization of Oil Removal Operations from Sunken Wrecks. Interspill; 2009.

48

PART | I

Introduction and the Oil Spill Problem

40. Etkin DS. Cost-Benefit Analyses for Wreck Oil Removal Projects, Proceedings of the Wrecks of the World: Hidden Risks of the Deep Conference. Linthicum, MD: Maritime Institute of Technology (MITAGS); 2009. 41. Etkin DS. Magnitude of Worldwide Potentially-Polluting Wreck Problem, Proceedings of the Wrecks of the World: Hidden Risks of the Deep Conference. Linthicum, MD: Maritime Institute of Technology (MITAGS); 2009. 42. Hassello¨v I-M, Morrison G, Rose´n L, Dahllo¨f I, Lindgren F, Knutsson J. Development of a Protocol for Risk Assessment of Potentially Polluting Shipwrecks in Scandinavian Waters, Proceedings of the Wrecks of the World: Hidden Risks of the Deep Conference. Linthicum, MD: Maritime Institute of Technology (MITAGS); 2009. 43. Cabioc’h F. The Wreck Concern in France and European Waters: Prioritization, Proceedings of the Wrecks of the World: Hidden Risks of the Deep Conference. Linthicum, MD: Maritime Institute of Technology (MITAGS); 2009. 44. Westerholm D. Repercussions of a Reactive Strategy and Need for a Proactive Strategy, Proceedings of the Wrecks of the World: Hidden Risks of the Deep Conference. Linthicum, MD: Maritime Institute of Technology (MITAGS); 2009.

Part II

Types of Oils and Their Properties

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Chapter 3

Introduction to Oil Chemistry and Properties Merv Fingas

Chapter Outline 3.1. Introduction 3.2. The Composition of Oil

51 51

3.3. Properties of Oil

54

3.1. INTRODUCTION Oil is a general term that describes a wide variety of natural substances of plant, animal, or mineral origin, as well as a range of synthetic compounds.1 This section covers mineral oil or petroleum oil. The many different types of crude oil are made up of hundreds of major constituents and thousands of minor ones. As their composition varies, each type of oil or petroleum product has certain unique characteristics or properties. These properties influence how the oil behaves when it is spilled and determines the fate and effects of the oil in the environment. These properties also influence the efficiency of cleanup operations. This section deals specifically with crude oils and petroleum products derived from crude oils and describes the chemical composition and physical properties.

3.2. THE COMPOSITION OF OIL Crude oils are mixtures of hydrocarbon compounds ranging from smaller, volatile compounds to very large, nonvolatile compounds.2 This mixture of compounds varies according to the geological formation of the area in which the oil is found and strongly influences the properties of the oil. For example, crude oils that consist primarily of large compounds are viscous and dense. Petroleum products such as gasoline or diesel fuel are mixtures of fewer compounds, and thus their properties are more specific and less variable. Crude oil contains many compounds of different sizes and different classes. In fact, Oil Spill Science and Technology. DOI: 10.1016/B978-1-85617-943-0.10003-6 Copyright Ó 2011 Elsevier Inc. All rights reserved.

51

52

PART | II

Types of Oils and Their Properties

there are so many that as time goes by more and more compounds are identified in oil.3 Figure 3.1 shows the number of compounds that are identified and quantified in oils by year as well as the prediction for the future. Some analysts have preliminarily identified up to 17,500 compounds in an oil. Hydrocarbon compounds are composed of hydrogen and carbon, which are therefore the main elements in oils. Oils also contain varying amounts of sulphur, nitrogen, oxygen, and sometimes mineral salts, as well as trace metals such as nickel, vanadium, and chromium. In general, the hydrocarbons found in oils are characterized by their structure. A common and older method of classification is by SARA dsaturates, aromatics, resins, and asphaltenes. Figure 3.2 illustrates the SARA classification along with classes of compounds typically found in this overall classification. The saturate group of components in oils consists primarily of alkanes, which are compounds of hydrogen and carbon with the maximum number of hydrogen atoms around each carbon. Thus, the term saturate is used because the carbons are “saturated” with hydrogen. The saturate group includes straight-chain alkanes and branched-chain alkanes and also includes cycloalkanes, which are compounds made up of the same carbon and hydrogen constituents, but with the carbon atoms bonded to each other in rings or circles. Straight-chain saturate compounds from C18 and up are often referred to as waxes. The aromatic compounds include at least one benzene ring of six carbons. Three carbon-to-carbon double-bonds float around the ring and provide

Compounds Identified

4000

3000

Prediction

2000

1000

0 1970

1980

1990

2000

2010

2020

Year FIGURE 3.1 The number of compounds identified and quantified in crude oils by year, including prediction in the future.

Chapter | 3

53

Introduction to Oil Chemistry and Properties

Groupings

Example Classes, Names, and Compounds

Saturates

alkanes

Chemical class Alternate name

Description

paraffins

Example compound

dodecane C12H26

cycloalkanes waxes

Aromatics

naphthanates

decalin n-alkanes C18-C80

Benzenes BTEX

benzene Benzene, Toluene, Ethylbenzene, Xylenes

PAHs

Naphthenoaromatics

Resins

Asphaltenes

anthracene

combinations of aromatics and cycloalkanes

tetralin

class of mostly anomalous polar compounds carbazole sometimes containing oxygen, nitrogen, sulphur, or metals

N

class of large anomalous compounds structures not known sometimes containing oxygen, nitrogen, metals, or sulphur

FIGURE 3.2 An overview of the classification of compounds with specific examples.

stability. Because of this stability, benzene rings are very persistent and can have toxic effects on the environment. The most common smaller aromatic compounds found in oil are often referred to as BTEX, or Benzene, Toluene, Ethyl-benzene, and Xylenes. Polyaromatic hydrocarbons or PAHs are compounds consisting of at least two benzene rings. PAHs make up between 0 and 60% of the composition of oil. The olefins, or unsaturated compounds, are another group of compounds that contain less hydrogen atoms than the maximum possible. Olefins have at least one double carbon-to-carbon bond that displaces two hydrogen atoms. Significant amounts of olefins are found only in refined products. Polar compounds are those that have a significant molecular charge as a result of bonding with compounds such as sulphur, nitrogen, or oxygen. The “polarity” or charge that the molecule carries results in behavior that may be different from that of other compounds. In the petroleum industry, the smallest polar compounds are called resins, which are largely responsible for oil adhesion. The larger polar compounds are called asphaltenes because they often make up the largest percentage of the asphalt commonly used for road construction. Asphaltenes often have very large molecules and, if in abundance in an oil, they have a significant effect on oil behavior.4 Bitumen, which comes from heavy oil deposits or tar sands, consists largely of asphaltenes that must be broken down to smaller compounds before refining. Crude oil is processed in refineries to yield petroleum products that are used for heating, transport, and chemical synthesis. Table 3.1 lists some of the

54

PART | II

Types of Oils and Their Properties

TABLE 3.1 General Characterizations of Product Distillation Ranges Product

Distillation Temperature Range ( C)

Approximate Carbon Number Range

Gasoline

30e200

5e12

Naphtha

100e200

8e12

Jet Fuel & Kerosene

150e250

11e13

Diesel fuel

160e400

13e17

Gas-Oil

220e350

Heavy fuel oils

315e540

20e45

Atmospheric residue

>450

30þ

Vacuum residue

>600

60þ

products produced by distillation, a primary refinery process. Table 3.2 gives the general composition of some typical fuels and oils.5 The following are the oils or fuels that be used to illustrate the fate, behavior, and cleanup of oil spills: l l l l l

l

gasolinedas used in automobiles diesel fueldas used in trucks, trains, and buses a light crude oil a heavy crude oil an intermediate fuel oil (IFO)da mixture of a heavy residual oil and diesel fuel used primarily as a propulsion fuel for ships (the intermediate refers to the fact that the fuel is between a diesel and a heavy residual fuel) bunker fueldsuch as Bunker C, which is a heavy residual fuel remaining after the production of gasoline and diesel fuel in refineries and often used in heating plants

3.3. PROPERTIES OF OIL The properties of oil discussed here are viscosity, density, specific gravity, solubility, flash point, pour point, distillation fractions, interfacial tension, and vapor pressure. These properties for the oils noted as examples above are listed in Table 3.3.5 Viscosity is the resistance to flow in a liquid. The lower the viscosity, the more readily the liquid flows. For example, water has a low viscosity and flows readily, whereas honey, with a high viscosity, flows slowly. The viscosity of the

(% e except for metals) Group

Compound Class

alkanes cyclo-alkanes

Diesel

Light Crude

50 to 60

65 to 95

55 to 90

25 to 80

25 to 35

20 to 30

45 to 55

35 to 45

0 to 20

0 to 10

2 to 10

5 to 15

5

waxes Olefins Aromatics BTEX

IFO

Bunker C

30 to 50 0 to 1

5 to 10

0 to 10

25 to 40

5 to 25

10 to 35

15 to 40

40 to 60

30 to 50

15 to 25

0.5 to 2.0

0.1 to 2.5

0.01 to 2.0

0.05 to 1.0

0.00 to 1.0

0 to 5

10 to 35

15 to 40

30 to 50

30 to 50

0 to 2

1 to 15

5 to 40

15 to 25

10 to 30

0 to 2

0 to 10

2 to 25

10 to 15

10 to 20

0 to 10

0 to 20

5 to 10

5 to 20

30 to 250

100 to 500

100 to 1000

100 to 2000

0 to 2

0 to 5

0.5 to 2.0

2 to 4

PAHs Polar Compounds resins asphaltenes Metals (in parts per million) Sulphur

Heavy Crude

0.02

0.1 to 0.5

Introduction to Oil Chemistry and Properties

Saturates

Gasoline

Chapter | 3

TABLE 3.2 Typical Composition of Some Oils and Petroleum Products

55

56

TABLE 3.3 Typical Oil Properties Property Viscosity

Units 

mPa.s at 15 C 

Density

g/mL at 15 C

Flash Point



Solubility in Water Pour Point

C

Diesel

0.5

2

0.72

0.84

Light Crude 5 to 50

Heavy Crude 50 to 50,000

Intemediate Fuel Oil

Bunker C

1000 to 15,000

10,000 to 50,000

0.78 to 0.88

0.88 to 1.00

0.94 to 0.99

0.96 to 1.04

35

45

30 to 30

30 to 60

80 to 100

>100

ppm

200

40

10 to 50

5 to 30

10 to 30

1 to 5



NR

40 to 30

40 to 30

10 to 10

5 to 20

C

35 to

10

35

30 to 50

10 to 30

10 to 20

5 to 15

27

27

10 to 30

15 to 30

25 to 30

25 to 35

100 C

70

1

2 to 15

1 to 10

e

e

200 C

100

30

15 to 40

2 to 25

2 to 5

2 to 5

85

30 to 60

15 to 45

15 to 25

5 to 15

100

45 to 85

25 to 75

30 to 40

15 to 25

15 to 55

25 to 75

60 to 70

75 to 85

mN/m at 15 C

Distillation Fractions % distilled at

300 C 

400 C residual NR ¼ not relevant

Types of Oils and Their Properties

65 

PART | II

API Gravity Interfacial Tension

Gasoline

Chapter | 3

Introduction to Oil Chemistry and Properties

57

oil is largely determined by the amount of lighter and heavier fractions that it contains. The greater the percentage of light components, such as small saturates, and the lesser the amount of asphaltenes, the lower the viscosity. As with other physical properties, viscosity is affected by temperature, with a lower temperature giving a higher viscosity. For most oils, the viscosity varies as the logarithm of the temperature, which is a very significant variation. Oils that flow readily at high temperatures can become a slow-moving, viscous mass at low temperatures. In terms of oil spill cleanup, viscosity can affect the oil’s behavior. Viscous oils do not spread rapidly, do not penetrate soil as readily, and are difficult to pump and skim. Density is the mass (weight) of a given volume of oil and is typically expressed in grams per cubic centimeter (g/cm3). It is the property used by the petroleum industry to define light or heavy crude oils. Density is also important as it indicates whether a particular oil will float or sink in water. As the density of fresh water is 1.0 g/cm3 at 15 C and the density of most oils ranges from 0.7 to 0.99 g/cm3, most oils will float on water. As the density of seawater is 1.03 g/cm3, even heavier oils will usually float on it. The density of oil increases with time, as the light fractions evaporate. Occasionally, when the density of an oil becomes greater than the density of freshwater or seawater, the oil will sink. Sinking is rare, however, and happens only with a few oils, usually residual fuels such as Bunker C. Significant amounts of oil have sunk in only about 25 incidents out of thousands. However, as heavier and heavier oils are being used more frequently, this may become more common in the future. Another measure of density is specific gravity, which is an oil’s relative density compared to that of water. If the oil-specific gravity is greater than 1, it sinks; if it is less than 1, it floats. Another gravity scale is that of the American Petroleum Institute (API). The API gravity is based on the density of pure water that has an arbitrarily assigned API gravity value of 10 (10 degrees). Oils with progressively lower specific gravities have higher API gravities. The following is the formula for calculating API gravity: API gravity ¼ [141.5 O (oil density at 15.5 C)] 131.5. Oils with high densities have low API gravities and vice versa. Solubility in water is the measure of how much of an oil will dissolve in the water column on a molecular basis. Solubility is important in that the soluble fractions of the oil are sometimes toxic to aquatic life, especially at higher concentrations. As the amount of oil lost to solubility is always small, this is not as great a loss mechanism as evaporation. In fact, the solubility of oil in water is so low (generally less than 100 parts per million) that it would be the equivalent of approximately one grain of sugar dissolving in a cup of water. Yet, even this small amount is important to the environment as even small amounts may be toxic to certain biota. The flash point of an oil is the temperature at which the liquid gives off sufficient vapors to ignite upon exposure to an open flame. A liquid is considered to be flammable if its flash point is less than 60 C. There is a broad range of flash points for oils and petroleum products, many of which are

58

PART | II

Types of Oils and Their Properties

considered flammable, especially when fresh. Gasoline, which is flammable under all ambient conditions, poses a serious hazard when spilled. Many fresh crude oils have an abundance of volatile components and may be flammable for as long as one day until the more volatile components have evaporated. On the other hand, Bunker C and heavy crude oils generally are not flammable even when spilled. The pour point of an oil is the temperature at which it takes longer than a specified time to pour from a standard measuring vessel. As oils are made up of hundreds of compounds, some of which may still be liquid at the pour point, the pour point is not the temperature at which the oil will no longer pour. The pour point represents a consistent temperature at which an oil will pour very slowly and therefore has limited use as an indicator of the state of the oil. In fact, pour point has been overused in the past to predict how oils will behave in the environment. For example, waxy oils can have very low pour points, but may continue to spread slowly at that temperature and can evaporate to a significant degree. It is important to note that pour point is not the solidification temperature. As produced crude oils become heavier, pour point becomes less relevant. Distillation fractions of an oil represent the fraction (generally measured by volume) of an oil that is boiled off at a given temperature. This data is obtained on most crude oils so that oil companies can adjust parameters in their refineries to handle the oil. This data also provides environmentalists with useful insights into the chemical composition of oils. For example, while 70% of gasoline will boil off at 100 C, only about 5% of a crude oil will boil off at that temperature and an even smaller amount of a typical Bunker C. The distillation fractions correlate strongly to the composition as well as to other physical properties of the oil. Equations to predict evaporation can use distillation fraction data as input. The oil/water interfacial tension, sometimes called surface tension, is the force of attraction or repulsion between the surface molecules of oil and water. Together with viscosity, surface tension is an indication of how rapidly and to what extent an oil will spread on water. The lower the interfacial tension with water, the greater the extent of spreading. In actual practice, the interfacial tension must be considered along with the viscosity because it has been found that interfacial tension alone does not account for spreading behavior. The vapor pressure of an oil is a measure of how the oil partitions between the liquid and gas phases, or how much vapor is in the space above a given amount of liquid oil at a fixed temperature. Because oils are a mixture of many compounds, the vapor pressure changes as the oil weathers. Vapor pressure is difficult to measure and is not frequently used to assess oil spills. Again as oil is a mixture of hundreds of compounds, vapor pressure is not entirely relevant. Although there is a high correlation between the various properties of an oil, these correlations should be used cautiously as oils vary so much in composition. For example, the density of many oils can be predicted based on their

Chapter | 3

Introduction to Oil Chemistry and Properties

59

viscosity. For other oils, however, this could result in errors. For example, waxy oils have much higher viscosities than would be implied from their densities. There are several mathematical equations for predicting one property of an oil from another property, but these must be used carefully as there are many exceptions.

REFERENCES 1. Neumann H-J, Paczynska-Lahme B, Severin D. Composition and Properties of Petroleum. New York: Halsted Press; 1981. 2. Speight JG. The Chemistry and Technology of Petroleum. 4th ed. Boca Raton, FL: CRC Press; 2007. 3. Marshall AG, Hendrickson CL. High-Resolution Mass Spectrometers, chapter in Annual Review of Analytical Chemistry, Volume 1, 2008, Young ES and Zare RN, editors., Annual Reviews, Palo Alto, CA, p. 579e99, 2008. 4. Groenzin H, Mullins OC. Asphaltene Molecular Size and Weight by Time-Resolved Fluorescence Depolarization, Chapter 2 in Asphaltenes, Heavy Oils and Petroleomics. In: Mullins OC, Sheu EY, Hammami A, Marshall AG, editors. New York: Springer Publications; 2007. p. 17. 5. Fingas MF. The Basics of Oil Spill Cleanup. 2nd ed. Boca Raton, FL: CRC Press; 2000.

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Part III

Oil Analysis and Remote Sensing

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Chapter 4

Measurement of Oil Physical Properties Bruce Hollebone

Chapter Outline 4.1. Introduction 4.2. Bulk Properties of Crude Oil and Fuel Products 4.3. Hydrocarbon Groups 4.4. Quality Assurance and Control

63 63 73 77

4.5. Effects of Evaporative Weathering on Oil Bulk Properties Appendix 4.1

78

85

4.1. INTRODUCTION During any uncontrolled release of oil, the properties of the spilled oil, including the bulk physical property changes due to weathering, must be immediately available, so that models can be used to predict the environmental impacts of the spill and guide the selection of various remediation alternatives. Unfortunately, the properties routinely measured by oil producers and refiners are not the ones that spill responders need to know most urgently. Questions important to responders include the following: l l

l l l l

the physical properties of the oil and how these change over time how the compositional and bulk property changes affect an oil’s behavior and fate whether emulsions will form whether the oil is likely to submerge the hazard to on-site personnel during cleanup the oil toxicity to marine or aquatic organisms

4.2. BULK PROPERTIES OF CRUDE OIL AND FUEL PRODUCTS The physical properties of the almost limitless variety of crude oils are generally correlated with aspects of chemical composition. Some of these key Oil Spill Science and Technology. DOI: 10.1016/B978-1-85617-943-0.10004-8 Copyright Ó 2011 Elsevier Inc. All rights reserved.

63

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Oil Analysis and Remote Sensing

properties for determining the fate and behavior of oil and petroleum products in the environment are viscosity, density, specific gravity (density relative to water), flash point, pour point, distillation, and interfacial tension. These properties for the oils are listed in Table 4.1. Viscosity is the resistance to flow in a liquid. The lower the viscosity, the more readily the liquid flows. The viscosity of an oil is a function of its composition; therefore, crude oil has a wide range of viscosities. For example, the viscosity of Federated oil from Alberta is 5 mPa$s, while a Sockeye oil from California is 45 mPa$s at 15 C . In general, the greater the fraction of saturates and aromatics and the lower the amount of asphaltenes and resins, the lower the viscosity. As oil weathers, the evaporation of the lighter components leads to increased viscosity. As with other physical properties, viscosity is affected by temperature, lower temperatures giving higher viscosities. For most oils, the viscosity varies approximately exponentially with temperature. Oils that flow readily at high temperature can become a slow-moving, viscous mass at low temperature. In terms of oil spill cleanup, viscous oils do not spread rapidly, do not penetrate soils readily, and affect the ability of pumps and skimmers to handle the oil. The dynamic viscosity of an oil can be measured by a viscometer using a variety of standard cup-and-spindle sensors at controlled temperatures. Density is the mass of a unit volume of oil, usually expressed as grams per millilitre (g/mL) or, equivalently, as kilograms per cubic metre (kg/m3). It is used by the petroleum industry to grade light or heavy crude oils. Density is also important because it indicates whether a particular oil will float or sink in water. As the density of water is 1.0 g/mL at 15 C and the density of most oils ranges from 0.7 to 0.99 g/mL, oils typically float on water. As the density of seawater is 1.03 g/mL, even heavier oils will usually float on it. Only a few bitumens have densities greater than water at higher temperatures. However, as water has a minimum density at 4 C and oils will continue to contract as temperature decreases, heavier oils, including heavy crudes and residual fuel oils, may sink in freezing waters. Furthermore, as density increases as the light ends of the oil evaporate off, a heavily weathered oil, long after a spill event, may sink or be prone to overwashing, where the fresh oil, immediately after the spill, may have floated readily. A related measure is specific gravity, an oil’s density relative to that of water. As the densities of both water and oil vary differently with temperature, this quantity can be highly variable. The American Petroleum Institute (API) uses the specific gravity of petroleum at 50 F (15.56 C) as a quality indicator for oil. Pure water has an API gravity of 10. Oils with progressively lower specific gravities have higher API gravities. Heavy, inexpensive oils have less than 25 API; medium oils are 25 to 35API; and light commercially valuable oils are 35 to 45API. API gravities generally vary inversely with viscosity and asphaltene content. Interfacial tensions are the net stresses at the boundaries between different substances. They are expressed as the increased energy per unit area (relative to the bulk materials), or equivalently as force per unit length. The ‘Standard

Chapter | 4

Intermediate Fuel Oil

Bunker C

Crude Oil Emulsion

1,000 to 15,000

10,000 to 50,000

20,000 to 100,000

0.88 to 1.00

0.94 to 0.99

0.96 to 1.04

30 to 50

10 to 30

10 to 20

5 to 15

10 to 15

27

10 to 30

15 to 30

25 to 30

25 to 35

N/A

55 to 65

30 to 30

30 to 60

80 to 100

>100

>80

55 to 0

30 to 30

10 to 10

5 to 20

>50

Property

Units

Gasoline

Diesel

Light Crude

Viscosity

m.Pa$s

0.5

2

5 to 50

Density

g/mL

0.72

0.84

0.78 to 0.88

50 to 65

35 to 40

27

API Gravity Interfacial Tension

mN/m

Flash Point



C

35

Pour Point



C

N/A

60

Heavy Crude 50 to 50,000

0.95 to 1.0

Measurement of Oil Physical Properties

TABLE 4.1 Typical Oil and Fuel Properties at 15 C

65

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Oil Analysis and Remote Sensing

International (SI)’ units for interfacial tension are milliNewtons per meter (mN/ m). Surface tension is thought to be related to the final size of a slick. The lower the interfacial tension of oil with water, the greater the extent of spreading and thinner terminal thickness of oil. In actual practice, the interfacial tension alone does not apparently account for spreading behavior; environmental effects and other effects seem to be dominant. The flash point of an oil is the temperature at which the vapor over the liquid can be ignited. A liquid is considered to be flammable if its flash point is less than 60 C. Flash point is an important consideration for the safety of spill cleanup operations. Gasoline and other light fuels can ignite under most ambient conditions and therefore are a serious hazard when spilled. Many freshly spilled crude oils also have low flash points until the lighter components have evaporated or dispersed. On the other hand, Bunker C and heavy crude oils generally are not flammable when spilled. The pour point of an oil is the temperature at which no flow of the oil is visible over a period of 5 seconds from a standard measuring vessel. The pour point of crude oils ranges from 60 C to 30 C. Lighter oils with low viscosities generally have lower pour points. As oils are made up of hundreds of compounds, some of which may still be liquid at the pour point, the pour point is not the temperature at which an oil will no longer pour. The pour point represents a consistent temperature at which an oil will pour very slowly and therefore has limited use as an indicator of the state of the oil. For example, waxy oils can have a very low pour point, but may continue to spread slowly at that temperature and can evaporate to a significant degree.

4.2.1. Density and API Gravity The density of an oil sample, in g/mL, is best measured using a digital density meter following American Society for Testing and Materials (ASTM) method D 5002.1 The instrument is calibrated using air and distilled, deionized water. Acoustically measured densities must be corrected for sample viscosity, as specified by the instrument manufacturer. API gravity (API 82) is calculated using the specific gravity of an oil at 60 F (15.56 C).2 The oil density at 15.56 C can be estimated by exponential extrapolation from the higher (THi) and lower (TLo) data points, if necessary. This is converted to specific gravity by division by the density of water at 15.5 C, using the following equation: s:g:15:56 ¼ rTHi exp

h

In rTHi

  THi

In rTLo

.

 TLo i.  15:56 þ In rTHi rðH2 OÞ15:56 THi

(1)

where s.g.15.56 is the specific gravity of the oil or product at 15.56 C (60 F), rTLo and rTHi are the measured oil densities at TLo and THi, respectively, and

Chapter | 4

Measurement of Oil Physical Properties

67

r(H2O)15.56 is the density of water at 15.56 C. The API gravity is then determined using the formula (API 82):   API ¼ 141:5= s:g:15:56 131:5 (2)

4.2.2. Dynamic Viscosity The dynamic viscosity of an oil sample, in mPa$s or cP, is measured using an enclosed spinning cup viscometer using standard NV and SV1 cup-and-spindle sensors.3 Check standards of pure ethylene glycol and glycerine can be conveniently used to validate the NV and SV1 methods, respectively. From a qualitative observation of the oil, either the NV or the SV1 sensor is chosen to measure the sample. The NV sensor is used for oils with viscosities below 100 mPa$s, and the SV1 sensor, for oils above 70 mPa$s to 10,000 mPa$s. For oils with higher viscosity, measurements must be made on cone and plate or parallel plate instruments (see below). For both cases using the rotary viscometer, the measurement cup is filled with a sample to the edge or the rotating surface. The sensor is mounted onto the instrument, and the sample volume is adjusted to the proper level. The sample is allowed to equilibrate until the sample temperature probe stabilizes at the measurement temperature and remains stable for 5 minutes. Samples and sensors are kept chilled at the appropriate temperature prior to use. For the NV sensor, the rotational shear rate is set at 1,000/s, the SV1 sensor at 50/s. If the oil is observed to be non-Newtonian, single samples are run at shear rates of 1/s, 10/s, and 100/s. In all cases, the sensors are ramped up to speed over a period of 5 minutes. The viscosity is measured for a subsequent 5 minutes, sampled once per second. The viscosity reported is that at time zero of the second, constant-shear rate interval. This may be obtained by the mean of the constant-shear rate interval data or by linear fit to the time-viscosity series if friction-heating has occurred during the measurement. For Newtonian samples, triplicate measurements are averaged and the mean is reported as the absolute or dynamic viscosity. For non-Newtonian samples, viscosities are reported for each of the three shear rates. Viscosities above 50,000 mPa$s are measured on a parallel plate rheometer with an air bearing. Measurement for most oils can be performed with a 35 mm plate/plate geometry at a gap of 2 mm between plates. A stress sweep in forced oscillation mode at 1 Hz performed over an appropriate range will determine the stress independent regions. A creep test can then be performed at a stress value selected in the stable “sol” range of flow response for the material. This provides the zero shear viscosity value.

4.2.3. Surface and Interfacial Tensions Surface and interfacial tensions, in mN/m, are normally determined by one of two methods. The de No€ uy ring is a common technique, used by many laboratories,

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Oil Analysis and Remote Sensing

and has been codified as ASTM method D 971.4 It depends on accurate measurement of the maximum force that a platinum ring can exert on the surface of a liquid before detachment. A second emerging technique that shows much promise for improved speed and accuracy is the pendant/rising drop method, which depends on shape calculations of a droplet of oil in air or water.5,6 The values that are important for spill responders include the oil/air, oil/ water, and the oil/seawater interfacial tensions. The oil/air interfacial tension is often called surface tension. As interfacial tensions are temperature dependent, it is often convenient to determine these quantities for several temperatures. Two measurements at freezing, 0 C, and at ambient temperature, 25 C, allow for a wide range of interpolated values. Measurement at 50 F/15 C also allows determination of common marine temperatures.

€ Ring Determination of Interfacial Tensions De Nouy A measurement apparatus specific to the de No€ uy ring test is required. Manual machines are common, but automated systems are now available that make measurements much quicker and repeatable. All measurement equipment, rings, measurement vessels, transfer, and storage containers must be scrupulously clean before measurement. Surface and interfacial tension measurements are very sensitive to contamination by organic chemicals or salts. For sample/air surface tensions, the instrument is zeroed with the measurement ring in the air. A small amount of sample, approximately 15 mL, is poured into a vessel of sufficient diameter that the wall effects on the meniscus do not affect the area through which the ring will pass. The ring is dipped into the sample to a depth of no more than 5 mm and is then pulled up such that it is just visible on the surface of the liquid. The system is allowed to rest for 30 seconds. The measurement is initiated, terminating when the upward pulling force on the ring just balances the downward force exerted by the liquid. The apparent surface tension, sAPP, is recorded. For sample/water and sample/brine interfacial tensions, the ring is zeroed in the sample at a depth of not more than 5 mm. The ring is removed and cleaned. A volume of water or brine is dispensed into the measurement vessel. The ring is dipped 5 mm into the aqueous phase. A small volume of sample is carefully poured down the side of the vessel wall, with great care taken so as to disturb the aqueous/oil interface as little as possible. The overlying layer should be at least 5 mm thick. The ring is then raised to the bottom on the interface, and the system is allowed to rest for exactly 30 seconds. The measurement is started, and the apparent interfacial tension is recorded, sAPP, when the force balance is reached. The apparent surface tension is corrected for mass of the upper phase lifted by the ring during measurement using the Zuidema and Waters6 correction: sffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi  1:452sAPP 1:679 þ 0:04534 (3) s ¼ sAPP 0:7250 þ C2 ðD dÞ R=r

Chapter | 4

Measurement of Oil Physical Properties

69

where s is the interfacial tension, sAPP is the instrument scale reading, C is the ring diameter, D is the density of the lower phase, d is the density of the upper phase, R is the radius of the du No€ uy ring, and r is the radius of the ring wire. As these measurements depend on temperature, samples, aqueous phases and glassware should be kept at the measurement temperature for a minimum of 30 minutes before a determination is made.

Pendant/Rising Drop Determination of Interfacial Tensions In this test, the interfacial tension is determined by calculation with comparison to the shape of a drop hanging from the end of a needle. A camera is used to photograph a picture of a drop hanging from a needle. The digital picture is analyzed by software; then a parameterized curve shape is developed, from which the surface tension is calculated.6 In the case of a liquideliquid interfacial tension, the surrounding fluid must be clear, so that a good image may be generated. For oil in water, this requires that the oil be suspended in water. However, as most oils are less dense than water, the rising oil bubble, rather than the pendant drop, must be measured. In this case, the image is inverted in software and, instead of the force of gravity, the buoyant force, determined as the fraction of gravity based on the specific gravity of the oil is used: b ¼ gðrwater

roil Þ=rwater

(4)

where b is the buoyant force, g is the acceleration due to gravity, rwater is the density of water at the measurement temperature, and roil is the oil density.

4.2.4. Flash Point The flash point of an oil product can be determined by several methods, depending on the oil product and the quantity available. Lower viscosity products, including light fuel oils and most fresh crudes, are measured by the Tag closed-cup method. This follows ASTM method D 1310.7 Though accurate, the Tag method uses a comparatively large volume of oil, 50 to 70 mL. Smaller volumes, 1e2 mL, can be measured by ASTM D6450.8 The practical working range of these two methods is e10 C to approximately 100 C. With subambient cooling, using dry ice baths and/or liquid nitrogen baths, much lower flash point temperatures can be measured, but this is often not necessary for emergency response considerations. Heavier products, including intermediate and heavy fuel oils, can be measured by a Pensky-Martins analyzer, following ASTM D 93.9 As with the Tag method, this method uses 50e70 mL of crude oil. Smaller volumes can be used with the newer method ASTM D7094, which uses only 2 mL of oil.10 The working range for these heavier type tests is approximately 50 C to 225 C.

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PART | III

Oil Analysis and Remote Sensing

The standard test material for assuring quality control for a lowertemperature flash point apparatus historically has been para-xylene; however, heavier normal alkane standards, n-decane, n-undecane, n-tetradecane, and n-hexadecane have also been found to be suitable and offer a wider range of test temperatures.11

4.2.5. Pour Point The pour point of an oil sample, in degrees Celsius, can only be determined by following ASTM method D 97.12 Sample aliquots are poured into ASTMapproved jars, stopped and fixed with ASTM-certified thermometers. The temperature regime described in the standard is critical; particularly in waxy oils, with high normal alkane contents, a crust of waxy crystals can form on the surface of the oil as it cools. The ASTM D 97 heating and cooling process for oil is designed to ensure that the formation of these microstructures does not interfere with reproducible measurement of the pour point.

4.2.6. Sulphur Content The mass fraction of atomic sulphur in oil is conveniently determined using X-ray fluorescence closely following ASTM method D 4294.13 In brief, the method is as follows: approximately 3 g of oil is weighed out into standard 31 mm XRF cells. The sealed cells are then measured in an XRF spectrometer. The spectrometer response is calibrated using a series of certified reference material standards. Spectra should be corrected for interference by chlorine by subtraction, based on a calibration curve established by the certified reference materials. Matrix effects, X-ray absorption by the base oil, can be corrected by subtraction of a spectrum of an oil free of sulphur, such as a mineral or lubricating oil.

4.2.7. Water Content The mass fraction of water in oil or an emulsion, expressed as a percentage, is best determined by Karl Fischer titration, using ASTM method D 4377.14 The Karl Fischer reaction is an amine-catalyzed reduction of water in a methanolic solution: CH3 OH þ SO2 þ RN/½RNHŠþ þ ½SO3 CH3 Š 2RN þ H2 O þ I2 þ ½RNHŠþ ½SO3 CH3 Š /½RNHŠþ ½SO4 CH3 Š þ 2½RNHŠþ I

(5)

The amine, RN, or mixture of amines is proprietary to each manufacturer. An aliquot of approximately 1 g of oil is accurately weighed, then introduced to the reaction vessel of the autotitrator. A solution of 1:1:2 (by volume) mixture of methanol:chloroform:toluene is used as a working fluid.

Chapter | 4

Measurement of Oil Physical Properties

71

4.2.8. Evaluation of the Stability of Emulsions Formed from Brine and Oils and Oil Products Water-in-oil emulsions are formed in 2.2-liter fluorinated vessels on an endover-end rotary mixer at a rotational speed of 50 RPM.15,16 1. 600 mL of salt water (3.3% w/v NaCl) is placed in each mixing vessel. 2. 30 mL of oil is added to each vessel for a 1:20 oil:water ratio. 3. The vessels are sealed and placed in the rotary mixer such that the cap of each mixing vessel follows, rather than leads, the direction of rotation. The rotary mixer is kept in a temperature-controlled cold room at 15 C. 4. The vessels and their contents are allowed to stand for approximately 4 hours before rotation begins, then mixed continuously for 12 hours. 5. At the conclusion of the mixing time, the emulsions are collected from the vessels for measurement of water content, viscosity, and the complex modulus. The emulsions are stored at 15 C for one week, then observed for changes in physical appearance. Water content for the emulsions should be determined. The Karl-Fischer titration method works well for all types of emulsion and watereoil mixtures. The complex modulus of the emulsion is measured on a rheometer using a 35 mm plate-plate geometry. A stress sweep is performed in the range 100 to 10,000 mPa in the oscillation mode at a frequency of 1 Hz. The complex modulus value in the linear viscoelastic region is reported.

4.2.9. Evaluation of the Relative Dispersability of Oil and Oil Products This method determines the relative ranking of effectiveness for the dispersibility of an oil sample by to a dispersant test mixture. It is used either to determine the effectiveness of a dispersant product for a standard crude oil or to test the dispersability of a crude oil against a standard dispersant. This method follows ASTM F 2059 closely.17 A premix of 1:25.0 dispersant:oil is made up by adding oil to 100 mg of dispersant (approximately 2.50 mL of oil in total). Six ASTM-standard swirling conical flasks modified with side spouts, containing 120 mL of 33& brine, are placed into an incubator-shaker. An aliquot of 100 mL of premix is added to the surface of the liquid in each flask, care being taken not to disturb the bulk brine. The flasks are mechanically shaken at 20.0 C with a rotation speed of 150 rpm for exactly 20 minutes. The solutions are allowed to settle for 10 minutes. Using the side spout, 30 mL of the oil-in-water phase is transferred to a 250 mL separatory funnel, first clearing the spout by draining 3 mL of liquid. The 30 mL aliquot is extracted with 35 mL of 70:30 (v:v) dichloromethane:pentane, collected into a 25 mL graduated cylinder.

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PART | III

Oil Analysis and Remote Sensing

A Gas Chromatograph-Flame Ionization Detector (GC/FID) is used to determine the oil concentration in the solvent. A 900 mL aliquot of the 15 mL solvent extract is combined with 100 mL of internal standard (200 ppm of 5-aandrostane in hexane) in a crimp-top injection vial and shaken well. The total petroleum hydrocarbon content of the sample is quantified by the internal standard method using the total resolved peak area and the average hydrocarbon response factor over the entire analytical range: RPH ¼ ATOTAL =AI:S: =RRF  20  15  120=30=0:9

(6)

where RPH is the resolved petroleum hydrocarbon (mg/mL), ATOTAL is the total resolved peak area, AI.S. is the internal standard peak area, and RRF is the relative response factor for a series of alkane standards covering the analytical range. The method is calibrated using a series of six oil-in-solvent mixtures prepared from the premix for each oil. The volume of premix dispersant/oil solution for each standard is selected to represent a percentage efficiency of the dispersed oil. The volume of the premix is then carefully applied to the surface of the brine in a shaker flask and shaken exactly as one of the samples, as described previously. Upon removal from the shaker however, the entire contents of the flask is transferred to the separatory funnel. This is extracted with 3  20 mL of 70:30 (v:v) dichloromethane:pentane and made up to 60 mL. Chromatographic quantitation is then performed using the formula: RPH ¼ ATOTAL =AI:S: =RRF  20  60  120=120=0:9

(7)

The RPH values as a function of % effectiveness for the calibration standards are plotted. The sample RPH values are then used to determine the percentage effectiveness of the dispersant. Note that these effectiveness percentages are not expected to correlate to real-world dispersabilities. It is important to remember that these values are relative rankings only.

4.2.10. Adhesion to Stainless Steel Adhesion to stainless steel is useful to responders in order to judge the “stickiness” of oil to certain drum skimmer configurations. Environment Canada has developed a quantitative test for this purpose.18,19 An analytical balance is prepared by hanging an ASTM method D 6 standard penetrometer needle from the balance hook and allowing the apparatus to stabilize and tare. Approximately 80 mL of oil sample is poured into a 100 mL beaker. The beaker is elevated until the oil reaches the top of the stainless steel needle. Care is taken not to coat the brass segment of the needle. The needle rests for 30 seconds immersed in the oil. The beaker is lowered until the needle is clear of the oil. The system is left undisturbed, closed inside a draft shield. After 30 minutes, the weight of the oil adhering to the needle is recorded. The

Chapter | 4

Measurement of Oil Physical Properties

73

mass of the oil divided by the surface area of the needle is the adhesion of the oil in g/cm2. Typically, four measurements are taken for each oil sample and the mean reported as the final value.

4.3. HYDROCARBON GROUPS The fate and behavior of crude oils and petroleum products are strongly determined by their chemistries. The main constituents of oils can be grouped into four categories: saturated hydrocarbons (including waxes), aromatics, resins, and asphaltenes. Saturates: A group of hydrocarbons composed of only carbon and hydrogen with no double bonds or aromaticity. They are said to be “saturated” with hydrogen. They may by straight-chain (normal), branched, or cyclic. Typically, however, the group of “saturates” refers to the aliphatics generally including alkanes, as well as a small amount of alkenes. The lighter saturates, those less than ~C18, make up the components of an oil most prone to weathering. The larger saturates, generally those heavier than C18, are termed waxes. Aromatics: These are cyclic organic compounds that are stabilized by a delocalized p-electron system. They include such compounds as BTEX (benzene, toluene, ethylbenzene, and the three xylene isomers), polycyclic aromatic hydrocarbons (PAHs, such as naphthalene), and some heterocyclic aromatics such as the dibenzothiophenes. Benzene and its alkylated derivatives can constitute several percent in crude oils. PAHs and their alkylated derivatives can also make up as much as a percent in crude oils. Resins: This is the name given to a large group of polar compounds in oil. They include heterosubstituted aromatics (typically oxygen- or nitrogencontaining PAHs), acids, ketones, alcohols, and monoaromatic steroids. Because of their polarity, these compounds are more soluble in polar solvents than the nonpolar compounds, such as waxes and aromatics, of similar molecular weight. Asphaltenes: A complex mixture of very large organic compounds that precipitate from oils and bitumen by natural processes. For the purposes of this method, asphaltenes are defined as the fraction that precipitates in n-pentane. The separation of petroleum and its products into these four characteristic groups is known as fractionation. The quantification of the groups is often referred to as SARA analysis, an acronym of the characteristic groups: saturates, aromatics, resins, and asphaltenes. Historically, many techniques have been used to perform this separation, including distillation, solvent precipitation (ASTM D6560)20, treatment with strong acids (ASTM D2006)21, adsorption (ASTM D2007 and D4124)22,23, and thin-layer chromatography.24 For reviews of the methods, see Speight and Becker.24-26 While excellent methods for the determination of the SARA groups have been developed using thin-layer chromatograph (TLC), there has been continuing interest in alternate

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test methods based on solvent separation and adsorption techniques.22-24 Gravimetric methods are typically based on the solubilities of the groups in n-pentane, hexane/benzene, and methanol.3 Such methods can rely on gravimetric determinations of all components, including the saturate and aromatic groups. However, the drawback of such methods is that they contain significant volatile components. This is particularly true of crude oils and lighter fuels. More sophisticated methods rely on a combination method involving determination of the saturate and aromatic fractions by gas chromatography, an adaptation of total petroleum hydrocarbon methods, while gravimetrically determining the nonvolatile resin and asphaltene components.27,28

Resin and Asphaltene Gravimetric Determination A 100 mL quantity of n-pentane is added to a preweighed sample of approximately 5 g of oil. The flask is shaken well and allowed to stand for 30 minutes.27 The sample is filtered through a 0.45 mm membrane using a minimum of rinsings of n-pentane. The precipitate is allowed to dry, then weighed. The weight of the precipitate as a fraction of the initial oil sample weight is reported as the percentage asphaltenes. The filtrate from the precipitation, the “maltene” fraction, is recovered and made up to 100 mL with n-pentane. A 15 g, a 1 cm diameter column of activated silica gel is prepared. The top of the column is protected by a 1 cm layer of sodium sulphate. A 5 mL aliquot of the maltene fraction is loaded onto the column. A 60 mL volume of 1:1 (v:v) benzene:hexane is eluted through the column and discarded. A 60 mL volume of methanol, followed by a 60 mL volume of dichloromethane, are eluted through the column and combined. The methanol/dichloromethane fractions are reduced by rotary evaporation and blown down to dryness under nitrogen. The mass fraction of this dried eluent, compensating for the volume fraction used, is reported as the percentage of resins in the sample. Resin and Asphaltene Thin-Layer Chromatography Determination While no standard method for this technique exists, it has the advantages over the gravimetric methods of being much faster, requiring much less oil or product and being more reproducible. It has the disadvantage of requiring a sophisticated instrument, a TLC with a flame ionization detector (FID). A TLC that quantifies analytes developed on silica gel-coated glass rods, such as the Iatroscan Mark 6, is necessary for this method. Briefly, an aliquot of sample dissolved in dichloromethane at a concentration of 1 mg/mL is spotted at a point, the origin, near one end of a rod, the foot of the rod. The rods are then developed by immersion of the feet into a series of solvents to separate the four hydrocarbon groups. The origin points must remain above the liquid surface, but the feet of the rods must be immersed sufficiently to cause solvent to travel up the rods by capillary action.

Chapter | 4

Measurement of Oil Physical Properties

75

The first solvent used is n-hexane to develop the saturates. Toluene develops the aromatics. Finally, a 95% dichloromethane, 5% methanol mixture is used to develop the resins. The asphaltenes remain at the spotting origin. The hydrocarbon groups that are not quantified by this method, the saturates and aromatics, are removed by pyrolysis. A known standard is then applied to the chromarod and then quantified using an FID and an internal standard. A sample of 1 octadecanol at 1 mg/mL concentration is a convenient internal standard. This is spotted on the rod just prior to measurement, on the part of the rod pyrolyzed to remove the saturate and aromatic fractions. The development of the chemicals on the rods critically depends on the conditions. The rods must be developed in tanks to control the vapors in atmosphere. Also, temperature and humidity must remain as consistent as possible in order to achieve reproducible results. When drying after each development, the rods must rest in a controlled humidity chamber. Resin and asphaltene contents are determined as follows: %Resin ¼ CIS  VIS  AR =AIS

(8)

%Asphaltene ¼ CIS  VIS  AA =AIS

(9)

where: CIS: Internal standard concentration VIS: Internal standard volume AIS: Internal standard area from TLC integration AR: Resin area from TLC integration AA: Asphaltene area from TLC integration Note that while saturate and aromatic fractions are separated by the development process and could, in principle, be measured by TLC-FID, the drying process between development stages requires significant evaporation. This level of evaporation is significant enough to remove most of the volatile components, which includes a large fraction of both saturates and aromatics (but not the resins or asphaltenes). For this reason, this TLC-FID method is not suitable for saturate or aromatic determination.

Saturate and Aromatic Chromatographic Determination This method is adapted and simplified from a previously published method for crude oil and petroleum product determination.28 An 80 mg/mL solution of oil is prepared in hexane. A 3.0 g column of activated silica-gel is prepared, topped with 0.5 cm anhydrous sodium sulphate. The column is conditioned with 20 mL of hexane. An amount of 200 mL of the oil solution, approximately 16 mg of oil, is quantitatively transferred onto the column using an additional 3 mL of hexane to complete the transfer. The eluent is also discarded. Just prior to exposure of

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PART | III

Oil Analysis and Remote Sensing

the sodium sulphate to the air, 12 mL of hexane is added to the column. The eluent is labeled fraction “F1.” F1 is considered to contain all the saturates, including the waxy components in the oil. The column is then eluted with 15 mL of 1:1 (volume:volume) benzene/ hexane or dichloromethane/hexane. The eluent is collected and labeled fraction “F2.” F2 is considered to contain the aromatic compounds in the oil, including the BTEX compounds, other alkylated benzene species, PAHs, and the alkylated PAH homologues. Half of fractions F1 and F2 are combined. This composite fraction is labeled “F3.” This fraction is used for analysis of total petroleum hydrocarbons (TPH). All the three fractions are concentrated under dry nitrogen. The fractions are then spiked with the internal standard, 100 mL of 200 ppm 5-a-androstane, and made up with hexane to 1 mL. The analysis for total petroleum hydrocarbons and saturates is performed by high-resolution capillary GC/FID using the following conditions: Column: Carrier Gas: Injection volume: Injector temperature: Detector temperature: Oven program:

30 m  0.32 mm ID HP DB5-HT fused silica column (0.10 mm film thickness); Helium, 3.0 mL/min, constant flow; 1.0 mL; 290 C; 325 C; 40 C for 2 minutes, followed by 25 C/minute to a final temperature of 340 C, then held for 15 minutes. The total run time is 29 minutes.

To calculate the concentration of hydrocarbons in each fraction, the area response attributed to the petroleum hydrocarbons must be determined. This area includes all of the resolved peaks and unresolved “hump.” This total area must be adjusted to remove the area response of the internal standards and GC column bleed. Column bleed is the reproducible baseline shift that occurs during the oven cycle of the GC. To determine this area, a hexane blank injection is analyzed before and after every 10 samples to determine the baseline response. The integration baseline is then set at a stable reproducible point just before the solvent peak. This baseline area for the blank run is subtracted from the actual sample run. The total areas of the chromatograms of F1, F2, and F3 are obtained by integration of all peaks, corrected by removal of the baseline. The area response attributable to the internal standard is calculated. The F3 fraction is used to calculate the TPH values for the oil.28 The F1 and F2 fractions are used to calculate the total saturate (TSH) and total aromatic (TAH) contents. Note that TPH should be within 10% of TSH þ TAH.

Chapter | 4

Measurement of Oil Physical Properties

77

As not all the oil is passed through the GC column, a simple sum of TSH, TAH, resin, and asphaltene contents will not equal 100%. This missing portion of the oil, which does not precipitate or get analyzed by the GC method, is approximated by proportionally dividing it into the saturate and aromatic portions. Thus the saturate content of the oil is commuted using: % Saturates ¼ TSH=ðTSH þ TAHÞð1

% Asphaltenes

% ResinsÞ (10)

Likewise, the aromatic content is computed using: % Aromatic ¼ TAH=ðTSH þ TAHÞð1

% Asphaltenes

% ResinsÞ (11)

Note that the asphaltene and resin contents may be determined by either gravimetric or TLC-FID method described earlier. For crude oils or products with high water content, it is necessary to dry the sample prior to the gravimetric determination of the hydrocarbon group contents. If a Karl-Fischer water content determination can be made, then the composition of the original product can be reported and adjusted for the observed water content. If not, the values should be reported as for dried product only.

4.4. QUALITY ASSURANCE AND CONTROL Most of the physical property methods described here rely on a single instrument and involve a simple measurement with little sample manipulation.28 For these methods, the instruments are calibrated as directed by the manufacturer or the appropriate ASTM method with chemical and/or gravimetric standards as appropriate. In addition, instrumental and operator performance should be monitored by periodic measurement of check standards. A control chart should be kept for each procedure, for the check or performance standard measurements. The check standard measurements are monitored closely. Failure of the check standard measurement to fall within the smaller of either a historical 95% confidence limit or the appropriate ASTM required repeatability should result in an investigation of the procedure. This typically includes required instrument maintenance, cleaning, recalibration, and measurement of the check standard until the desired precision and accuracy is reached. The chromatographic methods described here, including the dispersability tests and the hydrocarbon group analysis, involves significant sample preparation, followed by a measurement by gas chromatography. Such techniques require a higher level of effort to maintain quality assurance. Check or surrogate samples of either pure materials or certified reference standards should be processed in the same manner as the samples. Calibration should be accomplished with a second, separate set of certified reference materials. Internal standards should also be certified reference materials from reputable suppliers. Surrogate recovery, calibration stability, and internal standard response control charts should all be checked regularly to ensure procedure

78

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Oil Analysis and Remote Sensing

and measurement accuracy. Chromatograms should be checked to ensure that chromatographic quality, including good peak shape, baseline drift, column bleed, sample carryover, and chromatographic resolution are within acceptable limits.

4.5. EFFECTS OF EVAPORATIVE WEATHERING ON OIL BULK PROPERTIES Long experience has shown that the physical characteristics and chemical fingerprint of a crude oil can change greatly over the course of a spill incident. These changes have a profound effect on the fate, behavior, and effects of an oil in the environment. The oil may transmute to other states, evaporating, dissolving in water, or condensing to a semisolid residue, each new state having unique behaviors and eventual fates. In order to aid in the estimation and prediction of spill behavior, it is useful to know not only the characteristics of the fresh crude oil, but also those of oils at different stages of “weathering” in the environment. Previous work has shown that immediately after a spill, the dominant process of oil weathering is evaporation. The following discussion focuses on the effects of evaporative weathering on changes of oil physical properties and chemical compositions.

4.5.1. Weathering When oil is spilled, on either water or land, a number of transformation processes operate on the oil. In general, there are two types of transformation processes: the first is weathering, and the second is a group of processes (including spreading, movement of oil slicks, and sinking and ove-washing) related to the movement of oil in the environment. Weathering and movement processes overlap, with weathering strongly influencing how oil moves in the environment and vice versa. These processes depend very much on the type of oil spilled and the weather conditions during and after the spill. Thoroughly understanding the behavior of spilled oil in the environment is extremely important for development of oil spill models. Today’s sophisticated spill models combine the latest information on oil fate and behavior with computer technology to predict where the oil will go, what state it will be in, and when it gets there. “Weathering” is the term referring to a combination of a wide variety physical, chemical, and biological processes of a spilled oil in the environment. The weathering processes include evaporation, emulsification, natural dispersion, dissolution, microbial degradation, photo-oxidation, and other processes such as sedimentation, and oil-suspended particle interactions. Weathering has a very significant effect on most bulk oil properties. Unlike the chemical compositions, however, where environmental parameters only affect the rate and type of weathering, bulk properties of the oil are also highly variable depending on the physical conditions. The most important of these is

Chapter | 4

79

Measurement of Oil Physical Properties

temperature, but other factors such as pressure and the materials with which the oil is in contact also play a role. As an oil loses mass and changes in composition, several general trends in physical property changes can be observed: l

l

l

Density increases approximately linearly with increasing weathering. Density decreases approximately linearly with temperature. Viscosity increases with increasing weathering, but a simple functional relationship is not easy to develop. Viscosity increases approximately exponentially with decreasing temperature. Surface and interfacial tensions tend to increase slightly with increasing weathering.

4.5.2. Preparing Evaporated (Weathered) Samples of Oils A common technique for simulating weathering in the laboratory is evaporation. While this is only one of the possible processes in the natural environment, it is probably the dominant one for most spills, particularly in the first few hours or days following a spill. A laboratory oil-weathering technique by rotary evaporation allows for convenient preparation of artificially weathered oils with varying degrees of weight loss. A typical oil-weathering system consists of a rotary evaporator. The bath temperature of the evaporator should be variable from 20 C to 100 C  0.5 C. The rotation speed should be continuously variable from 10 to 135 rpm. The following evaporation procedure is used to evaporate oils: (1) The water bath is brought to a temperature of 80 C. (2) The empty rotary flask is weighed, and no more than one-third the volume of the rotary flask in oil is added and the flask reweighed. (3) The flask is mounted on the apparatus and the flask partially immersed in the water bath and spun at high speed, at least 120 rpm. A constant flow of air through the apparatus should be maintained by a vacuum pump. (4) At set intervals, the sample flask is removed and weighed. It is convenient to prepare two to three weathered samples for each type of oil measured. With a moderate flow rate through the instrument, a duration of 48 hours evaporation will come close, within 5 to 10%, to simulating the eventual final state of an oil in the environment. Intermediate fractions of approximately one- and two-thirds of the 48-hour loss by weight will simulate approximately the condition of the oil after a few hours to days and a few days to weeks of natural evaporation. The exact time taken to prepare these intermediate fractions is determined by estimation from the measured fractional mass-loss as a function of time for the 48-hour sample. The fraction mass-loss is calculated as: % weathering ¼ ðmi

mf Þ=ðmi

me Þ x 100%

(12)

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PART | III

Oil Analysis and Remote Sensing

where % weathering is the percentage evaporative mass-loss over the 48-hour period, mi is the initial mass of the flask and oil, mf is the final mass of the flask and oil, and me is the mass of the empty flask. A graph of % weathering as a function of time is plotted using the interval weighing data. The times for one-third (t1/3) and two-thirds (t2/3) of the 48-hour mass loss are interpolated from a time-weathering graph. Typical times for t1/3 range from 30 minutes to 2 hours, for t2/3, 8 to 12 hours. This technique allows for precise control of the evaporative weight loss for a target oil and can be directly correlated to bulk property and compositional changes of the weathered oil. By tracking weight loss as a function of time, an equation for predicting evaporation can be found. Also, from this same graph, it is possible to determine a point at which the evaporation rate is sufficiently slow that the oil may be considered to have achieved the maximum evaporative loss likely to be observed under the conditions of a marine spill.

(a)

0.94

0.94

Cook Inlet 2003

Cook Inlet 2003 vs.T

0.92

0.92

vs.W(%)

0.90

Density (g/mL)

Density (g/mL)

34.4% 25.0%

0.88

11.4%

0.86 Fresh 0.84

0.90 0.88 0.86

5 °C 15 °C

0.84 30 °C 0.82

0.82

0.80 0

5

10

15

20

25

30

35

0

10

Temperature (°C)

(b) 1.02

30

40

1.02

Platform Elly

Platform Elly vs.W(%)

vs.T 1.00

13.3%

0.98

7.9% 4.6%

0.96

Density (g/mL)

1.00

Density (g/mL)

20

Weathering (%)

0.98 5 °C 0.96

Fresh

15 °C 30 °C

0.94

0.94 0

5

10

15

20

25

Temperature (°C)

30

35

0

2

4

6

8

10

12

14

Weathering (%)

FIGURE 4.1 Density versus temperature and weathering for a light (Cook Inlet) (a) and heavy (Platform Elly) (b) crude oil.

Chapter | 4

81

Measurement of Oil Physical Properties

4.5.3. Quantifying Equation(s) for Predicting Evaporation The evaporation kinetics are determined for each oil by measuring the weight loss over time from a shallow dish.30,31 Approximately 20 g of oil is weighed into a 139 mm petri dish. The oil weight is recorded by an electronic balance accurate to 0.01 g at set intervals and collected on a computer logging system. Measurements are conducted in a climate-controlled chamber at 15 C. Temperatures are monitored by a digital thermometer. The evaporation period can last from a few days for light oils to weeks for heavier products. The time versus weight-loss data series are fitted to a set of simple equations. The best curve-fit is chosen as the equation for predicting evaporation.

Effects of Evaporative Weathering on Crude Oil Density Densities of oils typically increase approximately 5 to 10% as oil weathers. Cook Inlet, a light oil, changes from 0.84 g/mL to 0.91 g/mL at 30 C (see 10000

10000

Cook Inlet 2003 vs.W(%)

1000

Viscosity (mPas)

Viscosity (mPas)

Cook Inlet 2003 vs.T

100 34.4% 25.0% 10

1000

100

10

11.4% Fresh

1

5 °C 15 °C 30 °C

1 0

5

10

15

20

25

30

35

0

10

1e+7

30

40

1e+7

Platform Elly vs.T

1e+5 13.3% 1e+4 7.9% 4.6% 1e+3

Fresh

1e+2

1e+6

Viscosity (mPas)

1e+6

Viscosity (mPas)

20

Weathering (%)

Temperature (°C)

Platform Elly vs.W(%)

1e+5 5 °C 1e+4

15 °C 30 °C

1e+3

1e+2 0

5

10

15

20

25

Temperature (°C)

30

35

0

2

4

6

8

10

12

14

Weathering (%)

FIGURE 4.2 Viscosity versus temperature and weathering for light (Cook Inlet) and heavy (Platform Elly) crude oils.

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Oil Analysis and Remote Sensing

Figure 4.1a), while Platform Elly, a very heavy crude oil, has a fresh density of 0.9531 g/mL and increases to 0.9843 g/mL in its most weathered state at 30 C (Figure 4.1b). From Figure 4.1, it can be seen that, to a first approximation, 32

31

Cook Inlet 2003 vs. T o/a

30

34.4%

29

25.0%

28 11.4% 27 26 Fresh 25

Surface Tension (oil/air) (mN/m)

Surface Tension (oil/air) (mN/m)

32

24 15

20

25

30

34 o/w

vs.T

32 30 28 26

34.4% 25.0%

24

11.4% Fresh 22 0

5

10

15

20

25

30

vs.T

o/b

32 30 28 26 24

34.4% 25.0% 11.4%

22

Fresh

20 0

5

10

15

20

25

Temperature (°C)

30

30 °C

28 27 26 25

30 °C 15 °C 5 °C 0

35

10

20

30

40

34

vs.W(%)

o/a

32 30 28 26

5 °C 15 °C

24 30 °C 22 0

35

34

5 °C 15 °C

29

35

Interfacial Tension (oil/water) (mN/m)

10

Interfacial Tension (oil/3.3%brine) (mN/m)

Interfacial Tension (oil/water) (mN/m)

5

Cook Inlet 2003 vs.W(%) o/a

30

24 0

Interfacial Tension (oil/3.3%brine) (mN/m)

31

10

20

30

40

34

vs.W(%)

o/b

32 30 28 26 5 °C 24

15 °C

22 30 °C 20 0

10

20

30

40

Weathering (%)

FIGURE 4.3 Surface and interfacial tensions as a function of temperature and weathering for Cook Inlet (2003).

Chapter | 4

Measurement of Oil Physical Properties

83

density increases linearly with increasing mass-loss and decreasing temperature. Better extrapolations can be made from log-log extrapolations of both quantities. Note that the uncertainties in density are very small: 0.0002 g/mLdapproximately 1 part in 5,000.

Effects of Evaporative Weathering on Crude Oil Viscosity In contrast to most other physical properties, the viscosity of an oil can change by orders of magnitude with weathering and changes in temperature. For example, the viscosity of Cook Inlet (2003) changes from 5.8 mPa s to 67.0 mPa s at 30 C (see Figure 4.2), while fresh Platform Elly has a viscosity of 1070 mPa s, and reaches 52280 mPa s in the most weathered fraction (Figure 4.3). As can be seen from the logarithm of viscosity is roughly inversely linear with temperature, but the effects of weathering on viscosity are more complex. Uncertainties in viscosity are 5%. Effects of Evaporative Weathering on Crude Oil Surface and Interfacial Tensions Surface and interfacial tensions have no simple quantitative relationships in general to either the degree of weathering or the temperature. Surface tensions however, do not vary greatly from oil to oil; values from 25 mN/m to 32 mN/m are typical for almost all types of oil. Interfacial tensions for oil/water and oil/ 3.3% brine are often marginally lower than the corresponding oil/air surface tension. Oil/brine interfacial tensions are usually somewhat higher than the corresponding oil/(pure) water values. Typical values for both range from 18 mN/m to 32 mN/m. Surface and interfacial tensions tend to decrease with temperature and increase with weathering. Care should be taken not to overinterpret the significance of surface and interfacial tension values; however, the errors on these measurements are relatively large, 15%, and the relative variations of the values are fairly small.

REFERENCES 1. ASTM D 5002. Standard Test Method for Density and Relative Density of Crude Oils by Digital Density Analyzer. Conshohocken, PA: American Society for Testing and Materials (ASTM); 2009. 2. API 82. American Petroleum Institute (API), Petroleum Measurement TablesdVolume XI/XII. West Conshohocken, PA: American Society for Testing and Materials; 1982. 3. Jokuty P, Fingas M, Whiticar S. Oil Analytical Techniques for Environmental Purposes. AMOP 1994;245. 4. ASTM D 971. Standard Test Method for Interfacial Tension of Oil Against Water by the Ring Method. West Conshohocken, PA: American Society for Testing and Materials; 2009. 5. Jokuty P, Fingas M, Whiticar S, Fieldhouse B. A Study of Viscosity and Interfacial Tension of Oils and Emulsions, Manuscript Report EE-153, Ottawa, ON: Environment Canada, 1995.

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6. Song B, Springer J. Determination of Interfacial Tension from the Profile of a Pendant Drop Using Computer-aided Image Processing. Colloid Interface Sci. 1996;64. 7. ASTM D1310. Standard Test Method for Flash Point and Fire Point of Liquids by Tag Open-Cup Apparatus. West Conshohocken, PA: American Society for Testing and Materials; 2007. 8. ASTM D 6450. , Standard Test Method for Flash Point by Continuously Tester. West Conshohocken, PA: American Society for Testing and Materials; 2009. 9. ASTM D 93. American Society for Testing and Materials (ASTM), Standard Test Method for Flash Point by Pensky-Martens Closed Cup Tester. West Conshohocken, PA: American Society for Testing and Materials; 2009. 10. ASTM D 7094. Standard Test Method for Flash Point by Modified Continuously Closed Tester. West Conshohocken, PA: American Society for Testing and Materials; 2009. 11. Montemayor RG, Rogerson JE, Colbert JC, Schiller SB. Reference Verification Fluids for Flash Point Determination. J. Test. Eval. 1999;27. 12. ASTM D 97. Standard Test Method for Pour Point of Petroleum Oils. West Conshohocken, PA: American Society for Testing and Materials; 2009. 13. ASTM D 4294. Standard Test Method for Sulfur in Petroleum Products by Energy-Dispersive X-ray Fluorescence Spectroscopy. West Conshohocken, PA: American Society for Testing and Materials; 2009. 14. ASTM D 4377. Standard Test Method for Water in Crude Oils by Potentiometric Karl Fischer Titration. West Conshohocken, PA: American Society for Testing and Materials; 2009. 15. Fingas M, Fieldhouse B, Mullin J. Studies of Water-in-oil Emulsions: Stability and Oil Properties. AMOP 1998;1. 16. Fingas M, Fieldhouse B. Studies on Crude Oil and Petroleum Product Emulsions: Water Resolution and Rheology. Colloids Surf. A. 2009;67. 17. ASTM F 2059. Standard Test Method for Laboratory Oil Spill Dispersant Effectiveness Using the Swirling Flask. West Conshohocken, PA: American Society for Testing and Materials; 2007. 18. Jokuty P, Whiticar S, McRoberts K, Mullin J. Oil Adhesion TestingdRecent Results. AMOP 1996;9. 19. ASTM D 5. Standard Test Method for Penetration of Bituminous Materials. West Conshohocken, PA: American Society for Testing and Materials; 2009. 20. ASTM D 6560. Standard Test Method for Determination of Asphaltenes (Heptane Insolubles) in Crude Petroleum and Petroleum Products. West Conshohocken, PA: American Society for Testing and Materials; 2006. 21. ASTM D 2006. Method of Test for Characteristic Groups in Rubber Extender and Processing Oils by the Precipitation Method (Withdrawn 1975). West Conshohocken, PA: American Society for Testing and Materials; 1965. 22. ASTM D 2007. American Society for Testing and Materials (ASTM), Standard Test Method for Characteristic Groups in Rubber Extender and Processing Oils and Other PetroleumDerived Oils by Clay-Gel Absorption Chromatographic Method. West Conshohocken, PA: American Society for Testing and Materials; 2007. 23. ASTM D 4124. Standard Test Methods for Separation of Asphalt into Four Fractions. West Conshohocken, PA: American Society for Testing and Materials; 2006. 24. Barman BN. Hydrocarbon-Type Analysis of Base Oils and Other Heavy Distillates by ThinLayer Chromatography with Flame-Ionization Detection and by the Clay-Gel Method. J. Chromat. Sci. 1996;219. 25. Speight JG. The Chemistry and Technology of Petroleum. New York: Marcel Dekker; 2007. 26. Becker JR. Chapter 13, Asphaltene Test Methods, Crude Oil Waxes, Emulsions and Asphaltenes. Tulsa, OK: Penn Well Publishing Co; 1991.

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Measurement of Oil Physical Properties

27. Hollebone B, Wang Z, Landriault M, Smith P. A New Method for the Determination of the Hydrocarbon Groups in Oils: Saturates, Aromatics, Resins, and Asphaltenes (SARA). AMOP 2003;31. 28. Wang ZD, Fingas M, Li K. Fractionation of ASMB Oil, Identification and Quantitation of Aliphatic Aromatic and Biomarker Compounds by GC/FID and GC/MSD (Parts I and II). J. Chromat. Sci. 1994;361. 29. Environment Canada, Oil Properties Database, http://www.etc-cte.ec.gc.ca/databases/ OilProperties/oil_prop_e.html, accessed May 2010. 30. Fingas M. The Evaporation of Oil Spills. AMOP 1995;43. 31. Fingas M. Modeling Evaporation Using Models That Are Not Boundary-Layer Regulated. J. Haz. Mat. 2004;27.

APPENDIX 4.1 Table A4.1 gives the environmentally relevant properties of selected crude oils. TABLE A4.1 Environmentally-Relevant Properties of Selected Crude Oils29 Alaska North Slope Prudhoe Bay, Alaska, USA

Saudi Arabia

Mississippi Canyon Brent Blend Federated Block 807 Gulf of North Mexico, Sea, United Alberta, Louisiana, USA Kingdom Canada

Arabian Light

West Texas Intermediate

Texas USA

0 C

0.8777

0.8776

0.8472

0.8413

0.9310

0.8594

15 C

0.8663

0.8641

0.8351

0.8293

0.9461

0.8474

30.89

31.30

37.8

38.9

17.5

34.38

0 C

23.2

32.6

16

10

88.1

19.2



11.5

13

6

4

4.8

8.6

mN/m 0 C

27.3

27.2

28.0

27.3

28.8

27.4



26.4

26

25.5

25.8

28.2

26.0

mN/m 0 C

26.7

23.5

25.7

18.7

24.4

19.3



23.6

23.8

22.7

15.9

24.1

15.8

Oil-sea water Interfacial tension

mN/m 0 C

22.5

21.3

24.9

17.6

26.0

18.8



20.2

21.6

22.5

16.2

26.6

15.6

Flashpoint



C

< 8

< 10

< 30