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English Pages [139] Year 1986
A
CARLETON
CONTEMPORARY
PIPELINES& PERMAFROST -.o.//i
SCIENCE INA COLD
~CLIMATE Lightning Source Digital Printing Proof copy
Peter J. WilliaItls The Carleton Un iversity Press 1986
@Carleton University Press Inc .• 1986 ISBN 0-88629-056-2 Printed and bound in Canada.
Canadian Cataloguing in Publication Data Williams, Peter J. (Peter John). 1932 Pipelines and permafrost: science in a cold climate (A Carleton contemporary; 10) First published: London: Longman. 1979. Includes index. Bibliography ISBN 0-88629-056-2 I. Gas, Natural-Arctic regions--Pipe lines. 2. Petroleum--Arctie regions- Pipe lines. 3. Frozen ground-Arctic regions. I. Title. II. Series. TN880.5. W56
1986
621.8'672
CR7-0900 17-X
Distributed by: Oxford University Press Canada 70 Wynford Drive Don Mills. Ontario. Canada. M3C 1J9 (416) 441-2941 ACKNOWLEDGE M ENT Carleton University Press gratefully acknowledges the support extended to its publishing programme by the Canada Council and the Ontario Arts Council. Publication of this work was assisted by the Government of Canada: Public Awareness Program for Science and Technology.
CONTENTS
PREFACE ACKNOWLEDGEMENTS AN INTRODUCTORY NOTE
1
CHAPTER 1 THE CHALLENGE Oil and gas pipelines: early development Pipelines for cold regions 2 Pipelines and the public interest 5 6 Where does the "North" begin? 7 The freezing of soils Permafrost 9
CHAPTER 2 THE TERRAIN IN COLD REGIONS
13
Patterned ground 13 Solifluction and other soil movements on slopes Ice-wedge polygons, pingoes and palsar 18 Other ice in the ground and thermokarst 21 The climate of the ground 23
15
CHAPTER 3 A BRIEF HISTORY OF GEOTECHNICAL ACTIVITIES AND ASSOCIATED SCIENTIFIC RESEARCH IN THE NORTH 27 The passive, or pre-technological approach 27 Post-war Northern development and the geotechnical approach up to 1960 30 Pressure 34 34 The scientific approach What happens when soils freeze? 36 Conservation and concern for the natural environment 41
CHAPTER 4 THE TRANS-ALASKA PIPELINE The first big pipeline on permafrost 44 Permafrost and earthquakes 47 Terrain conditions and site investigations The pipeline and hydrological conditions Solutions to the problems 51 The completed pipclinc 58
45
48 50
CHAPTER 5 THE GAS PIPELINES AND THE FROST ,HEAVE PROBLEM 62 The Mackenzie Valley pipeline 62 Frost heave and the cold pipeline 64 Origin of the heaving pressure 65 Frost heave and the shut-off pressure 67 Measuring the movement of water through frozen 69 ground A difference of opinion 72 A change of plans 74 CHAPTER 6 THE ALASKA HIGHWAY PIPELINE The approved pipeline 78 Some general problems applying to gas pipelines Creeping soils, rivers, and glacier-dammed lakes The Alaska Highway Pipeline and the frost heave 86 problem Another change of plans 87
78 81 82
CHAPTER 7 MORE PIPELINES, MORE SCIENCE AND MORE POLITICS 91 Russian pipelines 92 The Norman Wells oil pipeline 93 Applied science carried out by a company 98 A pipeline bent in France 98 International science 104 More mega projects 106 CHAPTER 8 FREEZING GROUND, SCIENCE AND SOCIETY 109 Pipelines in cold places: the future 109 A new problem or an old one? III 112 A scientific challenge neglected Who is responsible? 113 The unanswered questions 116 Conclusion 117
PREFACE
Scientific flaws in the proposals for pipelines in cold places are the particular subject of this book. But the implications of the little-known, often contentious matters I describe extend to other costly engineering endeavours in even moderately cold lands. Furthermore, they provide a lesson from which modern society quite generally can learn. The challenges that are inherent in our complex and ambitious industrial technologies are not always what they seem to be. Problems that are of a scientific nature may go unrecognized for perceptual as well as for political or other reasons. It seems to me, however, that it is important to bring these problems to light so that those who have not been involved can be aware of the issues, which affect us all. In a period of less than ten years the extraction of the enormous reserves of gas and oil in the Arctic regions grew to be a major industrial and public issue in North America. These were industrial undertakings so huge that they came to be called megaprojects. Unlike the rapid oil and gas developments of the North Sea, however, only one major pipeline was completed in North America before the recession of 1981-82. and the later fall in gas and oil prices effectively suspended further construction. These events have obscured the fact that there are large gaps in our understanding of the cold regions and of the profound effects these have had on our striving for safe and cost-effective pipelines goals which are desirable to both the hydrocarbon industry and those concerned with their impact on the undisturbed Arctic surroundings. We cannot know exactly what would have happened had pipeline projects in Arctic North America been pushed ahead without the restraints that variously arose from government regulation and external economic factors. But the remarkable history of the two completed North American Arctic and sub-Arctic pipelines, as well as those now in abeyance, shows how serious the consequences of the lack of understanding of relatively simple science can be. The ground behaves in curious and unexpected ways when it freezes, often modifying the terrain in a conspicuous manner. It is not surprising, therefore, that there should be difficulties in placing constructions in freezing ground. The discovery of the problems associated with building the pipelines was belated and at times dramatic. The problems were, on a much larger scale, the same problems that road builders - or, indeed, anyone building in cold climates have long been aware of. The ability of the engineers to overcome or circumvent the milder effects, however, did not mean they were prepared for the challenges
Pipelines Ii Permafrost
of laying thousands of kilometres of the world's largest-diameter gas and oil pipelines through its coldest regions. Even today, what we know of the science involved is still relatively easy to explain, and is intriguing to specialist and non-specialist alike. This greatly simplifies an author's task when his aim is to demonstrate the importance of a widespread scientific understanding of such major practical issues. Indeed, a reviewer of the first edition of this book referred to my "heaven-sent" topic. Since then, changes in the world energy supply situation, a realization of the importance of the Soviet experience, the Siberian-Western Europe gas line, and various political and other ramifications have occurred. At the same time there have been developments in research into freezing ground and into cold climates so that the implications for geotechnical engineering have become somewhat more widely appreciated - albeit mainly by the specialists. Thus the story has expanded and the problems and paradoxes continue to develop. The most important questions for many now concern the future prices of oil and gas. The development of the world's umarginal" reserves, those where the costs of extraction and transport are higher than elsewhere, hinges on this. In turn these costs depend on the level of science and technology that can be brought to bear. The difficulties that proved so fateful during the frenetic striving towards construction in the seventies may turn out to be even more crucial if oil and gas prices continue to fluctuate sharply or rise only slowly. But quite independently of the petroleum industry people will continue to build in ground that freezes. For any such construction to be effective, safe and economic and without ill effects on the environment - whether it be dams or other major works in remote areas, or highways in populous places - true scientific understanding of the nature of the earth's surface is necessary. I did not write this book primarily for those who are specialists in the science of frozen ground. Some of them may, indeed, feel my approach superficial. although I hope not misleading. Others, though, may be interested in the role that science has played in the affairs of industry about which I write - a role that, one hopes, will be different and more productive in the future. Whether this will be so depends not so much on the scientists as on the policy makers in industry and in government and. it must be said. on the views of an informed pUblic. The latter group, especially, tends to read books only if they are interesting. If this one is, it is in considerable measure a result of many conversations I have had through the years with government officers, consultants and other professionals, and with my colleagues and students in the Geotechnical Science Laboratories research unit, Department of Geography, at Carleton University. It might be misunderstood if I name only some and it is impossible to name all, so I hope this can serve as acknowledgement of my indebtedness to those who, often without knowing it at the time, contributed to this book.
Prelace/Acknowledgements
The preparation of this second edition has also been a family affair. My wife, Kari, did much of the word processing, and my father J.G. Williams once again reviewed the text, greatly increasing its readability. My son prepared the index. My daughter found the text to be O.K. - in parts. Peter J. Williams Ottawa Canada
October 1986
ACKNOWLEDGEMENTS Permission to reproduce copyright material has been kindly given by: Academic Press Inc., T. Czudek and J. Demek for Fig.2.2 modified from Fig. 9 p.111 C7.udek and Demek 1970 _. Quaternary Research I; Alyeska Pipeline Service Company for Figs. 4.3 and 4.4 based on Figs. from p. 7 - Summary Project Description of the Trans-Alaska Pipeline System; American Meteorological Society for Fig. 2.3 modified from Fig. 4 Weller and Holmgren 1974 - Journal of Applied Meteorology 13; D.W. Patterson for Plate 19; Dr. Christopher Burn for Plate 2; Energy Mines and Resources, Canada for Fig.6.2 part of map 115 St. Elias - National Topographic System. Reproduced with permission; Energy Mines and Resources, Canada and Interprovincial Pipeline (NW) Ltd. for Plates 14. 15a and b, 16. and 17; National Research Council of Canada and the late R. J. E. Brown for Fig. 4.2. modified from Fig. from R. J. E. Brown, 1968 --- Permafrost Investigations in Northern Ontario and North Eastern Manitoba Tech. Paper 291; University of Toronto Press for Fig. 1.2 modified from Fig. 6 p. II and Fig. 1.3 modified from Fig. 4 p.8 R. J. E. Brown 1970 - Permafrost in Canada; John Wiley & Sons Inc. for Fig. 5.4 from Fig. 6 p. 354 Burt and Williams 1976 - Earth Sur/ace Processes I.
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Pipelines Permafrost
AN INTRODUCTORY NOTE
There have been several books written in popular style about the Northern pipeline megaprojects but, in my view, they have missed a most important point - arguably the most important point - and that is the topic of this book. Much of what has been written before on this topic has been in the special language of scientists, or of lawyers or others. Accuracy is important and some of the specialists may be concerned by my lack of respect for certain conventions in those kinds of writing, and others might be confused by what may still seem to be pedantry. A little explanation is necessary. Readers probably prefer pages uncluttered by superscripts or bracketed author references, but because the matters discussed are occasionally contentious, some will surely want to know my sources. Details can be interesting too. The notes at the end of each chapter are for these purposes and I have grouped them according to the subsections of the chapters. Because the subsections are short a glance at the relevant notes should identify the topics relative to the position in the text. 1 have used the SI or Systeme Internationale for units (the metric system, slightly modified) but I still refer to a 5-inch pipe, for example, asjust that. Most of my readers, even younger ones, know that an inch is a diminutive thumb, 2.54 centimetres to be exact, and they hardly need such conversions as "5 inches (12.7 centimetres)" or "I mile (1.61 kilometres)" repeatedly. Units for pressure are another matter. I use the Sf unit of Pascal (Pa) consistently except when explaining the magnitude of a pressure by analogy. Many readers may be uncertain about what "pressure" is, so it is useful to mention car tires (200,000 Pascals, or 200 kilo Pascals), the water pressure in the ocean depths (say, 50 million Pascals,or 50 MegaPascals, it all depends how deep), or in one's blood (about 10 to about 20 kiloPascals, as the heart beats). Remember the air around us, depending on the weather, has about 100 kilo Pascals - and that pressure is really to be added to each of those given, though we usually forget it and thus regard it as zero. More about this on p. 34. Pressures have to do with forces. Forces are involved in pushing and pulling and are measured in Newtons. The concentration of forces, Newtons per square metre is stress. A Paseal is also one Newton per square metre. There are brief references to stresses when we discuss landslides or the bending of pipes. The abreviated form is N m- 2• Joules appear occasionally but should not disturb the reader. The Joule (J) is simply the unit for energy and is used for amounts of heat. "Science", as in this book, is not "difficult" and should not only be for the initiated. Indeed it is not necessary to understand more about these things in order to understand the book, but there are a few additional simple explanations in the text.
CHAPTER
THE CHALLENGE
Most hom es in Nonh America arc hea ted by gas or fuel o il , wh ic h has been tran s ported g rea t di sta nces by pipe line. "No rth Sea gas" is a ho usehold
express ion in the United Kingdom. Modern industrialized nations depend in large mea s ure on these fu e ls for energy, and stab ilit y of s uppl y is a maj o r faclOf in int e rnati o nal politics. Na tural gas alone pr ov ides ab o ut a third of the total
energy requirement s in America, and the US Fede ral Energy Reg ulatory Commission has co mmented th at "when shortages of natural gas occur, as during the wint e r of 1976-77, the e ffect s are profound hard s hip and danger for
indi vidua ls and substantial economic disruption for the eco no my". Yet the linkages fo r this main spring of mod ern soc iety, the pipelines connecting wellhead and co nsu m er, arc usuall y taken as mu ch fo r granted as th e pipes that car ry water to Ollr h o me s. This attitude is unju sti fi ed bec au se de ve lo pment ha s ex tend ed pipeline operations to remote and inh os pitable places. while th e pipes th e mselves ha ve beco me large in diam eter , addin g great ly to th e comp lexi ti es. The cold reg ions, the North, a s Canadian s ca ll that part of their country, pro vided s uc h a c hall e nge at the end of th e s ix ti es . Th e assoc iat ed tec hnological demand s, th c sc ale of co nst ru ct ion and th e ofte n hu ge costs bring with them a hos t o f dangers, co mm e ns urat e on ly with th e increas ing dependence of socie ty on o it and gas. But th e hi sto ry of o il and gas pipe lin es goes back further than th e rccc nt decade s during w hich th e pipe lin e indu s try has come to carry s uch pot e ntial a nd responsib ilit y in res pect to huma n we ll -bei ng.
OIL AND GAS PIPELINES: EARLY DEVELOPMENT Oil ha s been tran s ported by pip e lin e for more th an a hundred yea rs. Th e firs t s uc h pipe line dat es bac k to 186 1, wa s apparentl y mad e o f wood. and was about 10 ce ntim ctres in diameter - it carried oi l so me 10 kil o metres in Pennsy lva nia. By 187 4 a pipe lin e 100 kilometres long carried o il to Pitt s burg. By 1878 a line over the Alleg he ny mountains had bee n prop osed . In s pite of the doubt s exp ressed. the lin e proved s ucces sful , and thu s for th e firs t time the s pecial difficulties of a particular te rrain had been ove rco m e. The hi s tory of gas pipe lin es is eve n o ld e r; for example Genoa had gas s tree t lightin g in 1802. The pipelines necessary for s ueh a sys tem were rudimcntary. Th e network ofnalUra l gas or coal gas dis tributi o n pipes of man y big cities by th e cn d of th e las t century in vo lve d on ly s m a ll d iameter pipes, us uall y mad e of iro n. But in the carl y part of th is ce ntury. pip e s izes increased rrom 3 to 6 in ches and even to 19 in ches in diamct er.
Pipelines i Permafrost
The difficulties of transporting gas and oil by pipeline increase with the size of the pipe, and so do the adverse consequences of a rupture, or leakage. During the Second World War relatively large diameter pipelines were introduced, with the Ubig-inch" (diameter 24 inches) running 2 000 kilometres, from Texas to Pennsylvania. In itself, a pipe of that diameter used to carry fluid was not a very novel or remarkable achievement. The Romans, although they did not use piping as understood today, constructed much larger aqueducts, of which one of the most famous is that crossing the Gard river near Nimes in France, supported on a magnificent arched structure - the Pont du Gard. Today tourists walk through the conduit high above the river. The explosive nature of gas or the polluting nature of spilled oil, however, and the necesssity of traversing particularly inhospitable parts of the earth's surface are twin challenges. Like the world's present pipeline networks themselves, the problems are extensive but not immediately obvious. From some II 000 kilometres in 1900, 40 000 by 1920 and perhaps 100 000 by 1940, the natural gas distribution system in the United States involved about 280 000 kilometres by the mid-1970s. For the most part, the pipelines are buried and not visible at the ground surface. Diameters of 14 inches to 30 inches are common. Pipelines constructed under particularly difficult or novel conditions have generally been of smaller diameter than elsewhere. The "pipeline under the ocean" (PLUTO) constructed during the second World War to carry oil from Britain to the continent was a mere 3 inches in diameter. It is only since around 1960 that the large-diameter pipes, 36 inches, 42 inches and even 48 inches, have come to dominate in the transport of oil and gas from highly productive but remote wells. One of the remarkable technological achievments of this century must surely be the tapping of the resources below the North Sea by this means. A passing knowledge, gained from television, newspaper or film, of the massive rigs and platforms battered by North Sea storms, of steel pipes that slide like giant spaghetti from pipe-laying boats, and of the successful installation of well pipe hundreds of meters below the sea bed, is sufficient to make us wonder whether any part of the earth's surface could be more challenging. PIPELINES FOR COLD REGIONS Major pipelines have been successfully constructed in very hot regions, in North Africa, the Middle East and elsewhere. The completion of the 30-inch TransArabian pipeline in 1950 was a notable achievment. A highly significant part of the North American reserves of oil and gas lie, by contrast, in the cold, most northerly part of the continent, particularly along the northern coast of Alaska, in the Canadian Arctic Islands and to some extent in the north-west of mainland Canada. The existence of this oil and gas has, for the most part, been established only in the last ten to twenty-five years. These regions have much permafrost, that is, ground that stays frozen throughout the year, and they are characterized by terrain conditions of great diversity, different from those of more temperate regions. Thus, pipeline construction in northern North America and in Siberia is the latest challenge for the world's petroleum industries and its extent and impact may become much greater in the last years of the twentieth century. 2
The Challenge
During the Second World War, the Canol pipeline, so me 2 000 ki lometres of 6-inch , 4-inch and 3-inch pipe, carried oil from Norman Wells to Whitehorse in Ca nada, and on to Fairbanks in Alaska (Fig. 1.1). It was intended to ensure security of supply for Alaska under the threat of a Japanese attack on supply . routes up the west coast. The pipe was laid on the ground surface, and it crossed the mountain s of th e Yukon. Some 25 000 people were involved in its constructi o n, and the cost was $134 million . But although in the year following completion there was a six-fold increase in Norman Wells production , at the end of the war production fell almost back to pre-war levels and the pipeline was dismant led. An 8-inch pipe was bUIlt in 1956 from Haines to Fairbanks, Alaska, partly buried and occasionally passing through permafrost, and it transported military fu el supplies for so me fifteen years. Only one major oil pipeline has been co mpleted in the permafrost region of North America - th e Trans-Alaska "Alyeska" line, an d its remarkable story is to ld in Chapter 4.
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