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Trans-Alaska Pipeline System

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Trans-Alaska Pipeline
The Trans-Alaska Pipeline
The Trans-Alaska Pipeline
Map of Trans-Alaska Pipeline
Location
CountryAlaska, USA
Coordinates70°15′26″N 148°37′8″W / 70.25722°N 148.61889°W / 70.25722; -148.61889
General directionNorth-South
FromPrudhoe Bay, Alaska
Passes throughDeadhorse, Delta Junction, Fairbanks, Fox, Glennallen, North Pole
ToValdez, Alaska
Runs alongsideDalton Highway, Richardson Highway, Elliott Highway
General information
Typeoil
Commissioned1973
Technical information
Length800 km (500 mi)
Maximum discharge2.1 million barrels per day (330,000 m3/d)

The Trans-Alaska Pipeline System (TAPS), usually called the Alyeska Pipeline in Alaska or the Alaska Pipeline elsewhere, is a major U.S. oil pipeline connecting oil fields in Alaska's North Slope to a North Pacific seaport where the oil can be shipped to the Lower 48 states for refining.

The main Trans-Alaska Pipeline runs north to south, almost 800 miles (1,300 km), from the Arctic Ocean at Prudhoe Bay, Alaska to the Gulf of Alaska at Valdez, Alaska, passing near several Alaskan villages and towns, including Wiseman (pop. 21), Bettles (pop.39), Livengood (pop.29), Fox (pop.300), Fairbanks (pop. 34,540), and Glennallen (pop.554) [see map].

Construction of the pipeline through the sparsely-populated region presented significant challenges due to the difficult terrain and the harsh environment along the route. Between the North Slope and Valdez, there were three mountain ranges, active fault lines, miles of unstable, boggy ground underlain with frost, hundreds of streams and rivers, and migration paths of caribou and moose. Deer and elk are also affected by the construction. Geological activity has damaged the pipeline on several occasions.[citation needed]

Since its completion in 1977, the pipeline has transported over 15 billion barrels (2.4 TL) of oil.

Origins

In 1909, geologist Alfred Hulse Brooks discovered oil seepages at Cape Simpson in the far north of Alaska, east of the village of Barrow.[1] Similar seepages were found at the Canning River in 1919 by Ernest de Koven Leffingwell.[2] Following the First World War, as the United States Navy converted its ships from coal to oil, the importance of securing a stable supply of oil became important to the U.S. government. Accordingly, President Warren G. Harding established a series of naval petroleum reserves across the United States. These reserves were areas thought to be rich in oil and set aside for future drilling by the U.S. government. Naval Petroleum Reserve No. 4 was sited in Alaska's far north, just south of Barrow, and encompassed 23,000,000 acres (93,078 km2).[3]

The petroleum reserve lay dormant until the Second World War provided an impetus to explore new oil prospects. Starting in 1944, the U.S. Navy funded oil exploration near Unimat Mountain, on the Colville River in the Brooks Range. Surveyors from the U.S. Geological Survey spread across the petroleum reserve and worked to determine its extent until 1953, when the Navy suspended funding for the project. The USGS found several small oil fields, most notably the Unimat Oil Field, but none were deemed particularly feasible to develop.

Four years after the Navy suspended its survey, Richfield Oil Corporation (later Atlantic Richfield and ARCO) drilled an enormously successful oil well near the Swanson River in southern Alaska, near Kenai. The resulting Swanson River Oil Field was Alaska's first commercially producing oil field, and it spurred the exploration and development of many others. By 1965, five oil and 11 natural gas fields had been developed. This success and the previous Navy exploration of its petroleum reserve led petroleum engineers to the conclusion that the area of Alaska north of the Brooks Range surely held large amounts of oil and gas. The problems came from the area's remoteness and harsh climate. It was estimated that between 200 million and 500 million barrels of oil would have to be recovered to make a North Slope oil field commercially viable.

In 1967, Atlantic Richfield (ARCO) began detailed survey work in the Prudhoe Bay area. By January 1968, reports began circulating that natural gas had been discovered by a discovery well. On March 12, 1968, an Atlantic Richfield drilling crew finally hit paydirt. A discovery well began flowing at the rate of 1,152 barrels of oil per day. On June 25, ARCO announced that a second discovery well likewise was producing oil at a similar rate. Together, the two wells confirmed the existence of the Prudhoe Bay Oil Field. The new field contained more than 25 billion barrels of oil, making it the largest in North America and the 18th largest in the world.

The problem soon became how to develop the oil field and ship product to U.S. and global markets. Several solutions were offered. Boeing proposed a series of 12-engine tanker aircraft to transport oil from the field.[4] General Dynamics proposed a line of tanker submarines for travel beneath the Arctic ice cap, and another group proposed extending the Alaska Railroad to Prudhoe Bay.[5] But the most notable alternative to pipeline transport was the idea that oil tankers could be used to transport the oil directly from Prudhoe Bay.

In 1969, Humble Oil and Refining Company sent a specially fitted oil tanker, the SS Manhattan, to test the feasibility of transporting oil via ice-breaking tankers to market.[6] The SS Manhattan was fitted with a massive ice-breaking bow, powerful engines, and hardened propellers before successfully traveling the Northwest Passage from the Atlantic Ocean to the Beaufort Sea. During the voyage, the ship suffered damage to several of its cargo holds, which flooded with seawater. Wind-blown ice forced the Manhattan to change its intended route from the McLure Strait to the smaller Prince of Wales Strait. Although the Manhattan successfully transited the Northwest Passage again in the summer of 1970, the concept was considered too risky.[7] A pipeline was thus the only viable system for transporting the oil to the nearest port free of pack-ice, almost 800 miles (1,300 km) away at Valdez.

Before Alyeska

In February 1969, before the SS Manhattan had even sailed from its East Coast starting point, the Trans-Alaska Pipeline System (TAPS), an unincorporated joint group created by ARCO, British Petroleum, and Humble Oil, asked for permission from the United States Department of the Interior to begin geological and engineering studies of a proposed oil pipeline route from Prudhoe Bay to Valdez, across Alaska. Even before the first feasibility studies were begun, the oil companies chose determined the approximate route the pipeline would take.[8] Permission was given, and teams of engineers began drilling core samples and surveying in Alaska.

Because TAPS hoped to begin laying pipe by September 1969, orders were placed for large amounts of 48-inch diameter steel pipeline. No American company manufactured pipe of that size, so three Japanese companies—Sumitomo Metal Industries Ltd., Nippon Steel Corporation, and Nippon Kokan Kabushiki Kaisha—received a $100 million contract for more than 800 miles of pipeline. At the same time, TAPS placed a $30 million order for the first of the enormous pumps that would be needed to push the oil through the pipeline.[9]

In June 1969, as the SS Manhattan traveled through the Northwest Passage, TAPS formally applied to the Interior Department for a permit to build an oil pipeline across 800 miles of public land—from Prudhoe Bay to Valdez.[10] The application was for a 100-foot (30.5-meter) wide right of way to build a subterranean 48-inch (122-centimeter) pipeline including 11 pumping stations. Another right of way was requested to build a construction and maintenance highway paralleling the pipeline. A brief 20-page document outlined all the information TAPS had collected about the route to that point in its surveying.[11]

The Interior Department responded by sending personnel to analyze the proposed route and plan. Max Brewer, an arctic expert in charge of the Naval Arctic Research Laboratory at Barrow, concluded that the plan to bury most of the pipeline was completely unfeasible because of the abundance of permafrost along the route. In a report, Brewer said the hot oil conveyed by the pipeline would melt the underlying permafrost, causing the pipeline to fail as its support turned to mud. This report was passed along to the appropriate committees of the U.S. House and Senate, which had to approve the right-of-way proposal because it asked for more land than authorized in the Mineral Leasing Act of 1920 and because it would break a development freeze imposed in 1966 by former Secretary of the Interior Stewart Udall.[12]

Udall imposed the freeze on any projects involving land claimed by Alaska Natives in hopes that an overarching Native claims settlement would result. In the fall of 1969, the Department of the Interior and TAPS set about bypassing the land freeze by obtaining waivers from the various native villages that had claims to a portion of the proposed right of way. By the end of September, all the relevant villages had waived their right-of-way claims, and Secretary of the Interior Wally Hickel asked Congress to lift the land freeze for the entire TAPS project. After several months of questioning by the House and Senate committees with oversight of the project, Hickel was given the authority to lift the land freeze and give the go-ahead to TAPS.

TAPS began issuing letters of intent to contractors for construction of the "haul road", a highway running the length of the pipeline route to be used for construction. Heavy equipment was prepared, and crews prepared to go to work after Hickel gave permission and the snow melted. Before Hickel could act, however, several Alaska Native and conservation groups asked a judge in Washington, D.C. to issue an injunction against the project continuing. Several of the native villages that had waived claims on the right of way reneged because TAPS had not chosen any Native contractors for the project, and the contractors chosen were not likely to hire Native workers.

On April 1, 1970, Judge George Luzerne Hart, Jr., of the United States District Court for the District of Columbia, ordered the Interior Department to not issue a construction permit for a section of the project that crossed one of the claims. Less than two weeks later, Hart heard arguments from conservation groups that the TAPS project violated the Mineral Leasing Act and the National Environmental Policy Act, which had gone into effect at the start of the year. Hart issued an injunction against the project, preventing the Interior Department from issuing a construction permit and halting the project in its tracks.[13]

After the Department of the Interior was stopped from issuing a construction permit, the unincorporated TAPS consortium was reorganized into the new incorporated Alyeska Pipeline Service Company. Former Humble Oil manager Edward L. Patton was put in charge of the new company and began to lobby strongly in favor of an Alaska Native claims settlement to resolve the disputes over the pipeline right of way.[14]

Opposition

Opposition to construction of the pipeline came from two primary sources: Alaska Native groups and conservationists. Alaska Natives were upset that the pipeline would cross land traditionally claimed by a variety of groups but would not contribute economically to those groups. Conservationists were angry at what they saw as an incursion into America's last wilderness.[15] Both opposition movements launched legal campaigns to halt the pipeline and were successful in preventing construction from 1970 to 1973.

Conservation objections

A caribou walks next to a section of the pipeline north of the Brooks Range. Opponents of the pipeline asserted the presence of the pipeline would interfere with the caribou.

Although conservation groups and environmental organizations voiced opposition to the pipeline project before 1970, the introduction of the National Environmental Policy Act allowed them legal grounds to halt the project. Arctic engineers had raised concerns about the way plans for a subterranean pipeline showed ignorance of Arctic engineering and permafrost in particular.[16] A clause in NEPA requiring a study of alternatives and another clause requiring an environmental impact statement turned those concerns into tools used by the Wilderness Society, Friends of the Earth, and the Environmental Defense Fund in their spring 1970 lawsuit to stop the project.[17]

Due to the injunction against the project, Alyeska was forced to do further research throughout the summer of 1970. The collected material was turned over to the Interior Department in October 1970,[18] and a draft environmental impact statement was published in January 1971.[19] The statement met with massive criticism from almost the moment it was released. The statement amounted to 294 pages but generated more than 12,000 pages of testimony and evidence in Congressional debates by the end of March.[20] Criticisms of the project included its effect on the Alaska tundra, possible pollution, harm to animals, geographic features, and the lack of much engineering information from Alyeska. One element of opposition the report quelled was the discussion of alternatives. All the proposed alternatives—extension of the Alaska Railroad, an alternative route through Canada, establishing a port at Prudhoe Bay, and more—were deemed to pose more environmental risks than construction of a pipeline directly across Alaska.[19]

Opposition also was directed at the building of the construction and maintenance highway parallel to the pipeline. Although a clause in Alyeska's pipeline proposal called for removal of the pipeline at a certain point, no such provision was made for removal of the road. Sydney Howe, president of the Conservation Foundation, warned: "The oil might last for fifty years. A road would remain forever."[21] This argument relied upon the slow growth of plants and animals in far northern Alaska due to the harsh conditions and short growing season. In testimony, an environmentalist argued that arctic trees, though only a few feet tall, had been seedlings "when George Washington was inaugurated".[22]

The portion of the environmental debate with the biggest symbolic impact took place when discussing the pipeline's impact on caribou herds.[23] Environmentalists proposed that the pipeline would have an effect on caribou similar to the effect of the U.S. transcontinental railroad on the American Bison population of North America.[23] Pipeline critics said the pipeline would block traditional migration routes, making caribou populations smaller and making them easier to hunt. This idea was exploited in anti-pipeline advertising, most notably when a picture of a forklift carrying several legally shot caribou was emblazoned with the slogan, "There is more than one way to get caribou across the Alaska Pipeline".[24] The use of caribou as an example of the pipeline's environmental effects reached a peak in the spring of 1971, when the draft environmental statement was being debated.[24]

Native objections

Main article: Alaska Native Claims Settlement Act

In 1902, the United States Department of Agriculture set aside 16,000,000 acres (64,750 km2) of Southeast Alaska as the Tongass National Forest.[25] Tlingit natives who lived in the area protested that the land was theirs and had been unfairly taken. In 1935, Congress passed a law allowing the Tlingits to sue for recompense, and the resulting case dragged on until 1968, when a $7.5 million settlement was reached.[26] Following the Native lawsuit to halt work on the Trans-Alaska Pipeline, this precedent was frequently mentioned in debate, causing pressure to resolve the situation more quickly than the 33 years it had taken for the Tlingits to be satisfied.[27] Between 1968 and 1971, a succession of bills were introduced into the U.S. Congress to compensate statewide Native claims.[28] The earliest bill offered $7 million, but this was flatly rejected.[29]

The Alaska Federation of Natives, which had been created in 1966, hired former United States Supreme Court justice Arthur Goldberg, who suggested that a settlement should include 40 million acres of land and a payment of $500 million.[29] The issue remained at a standstill until Alyeska began lobbying in favor of a Native claims act in Congress in order to lift the legal injunction against pipeline construction.[29] In October 1971, President Richard Nixon signed the Alaska Native Claims Settlement Act. Under the act, Native groups would renounce their land claims in exchange for $962.5 million and 148,500,000 acres (601,000 km2) in federal land. The money and land were split up among village and regional corporations, which then distributed shares of stock to Natives in the region or village. The shares paid dividends based on both the settlement and corporation profits.[30]

Construction

The oil companies with exploration rights grouped together as the Alyeska consortium to create a company, the Alyeska Pipeline Service Company, to design, build, and then operate the pipeline. US President Richard Nixon signed the Trans-Alaska Pipeline Authorization Act into law on 16 November 1973, which authorized the construction of the pipeline.

The pipeline crossing the Tanana River

The single 48 inch (1.22 m) diameter pipeline was built between 27 March 1975 to 31 May 1977 at a cost of about $8 billion.[31] The pipeline was constructed in six sections by five different contractors employing 21,000 people at the peak of work; 31 workers died in construction accidents.

The 800-mile (1,286 km) route presented special challenges. As well as the harsh environment, the need to cross three mountain ranges and many rivers and streams, the permafrost of Alaska meant that more than half of the pipeline's length had to be elevated rather than buried as normal to prevent the ground melting and shifting. There were five years of surveying and geological sampling before construction began. During construction archaeological teams were repeatedly called in to investigate previously unknown sites which were disturbed by excavation.

Technical details

Along the pipeline there are eleven pump stations, each with four pumps. Each electric pump is powered by diesel or natural gas generators. Twelve pump stations were planned but Pump Station 11 was never built, though the southward numbering system for the pump stations retains a place for this nonexistent station. Usually only around seven stations are active at one time, and plans to replace the existing pumps with newer high-efficiency pumps may reduce the number of active stations even further.

The pipeline was built above ground in areas where thaw-sensitive permafrost exists. Where the line must be buried, such as highway crossings or avalanche-prone areas, the pipe is encased in an insulated, refrigerated ditch. Nearby refrigeration plants pump cold brine through 6 inch (15 cm) pipes which absorb heat and keep the soil cooled. Other areas of burial are either conventional covered ditches or unrefrigerated but insulated ditches, depending on the sensitivity of the surrounding soil.

View of the pipeline's underside, heat pipes, and heat exchangers

Oil emerges from the ground at up to 180 °F (80 °C), and travels through the pipeline at temperatures above 120 °F (50 °C). In some elevated portions, heat conduction from the oil through the Vertical Support Members (VSMs) would melt the permafrost in which the VSMs are embedded. This would cause the pipeline to sink and possibly sustain damage. To prevent this, these portions of the pipeline include heat exchangers atop each VSM, passively cooled by convection to the air. Each heat exchanger is thermally coupled by a heat pipe to the base of the VSM. Running through the VSM, the heat pipe transports heat from the base to the heat exchanger. Since ammonia, the working fluid in the heat pipes, has a freezing point lower than the permafrost, the heat pipe works throughout the year, even during the coldest winter nights. This convection cooling system is thought by TAPS engineers to be the greatest innovation associated with the pipeline.

Another innovation associated with the pipline is the zig-zag configuration aboveground. Since pipe shifts around far more easily aboveground than when buried, the zig-zag path of the pipeline allows the pipe to move from side to side and lengthwise. This movement may be caused by earthquakes or by thermal expansion and contraction. The VSMs also include "shoes" to allow for horizontal or lateral movement, and crushable blocks to absorb shocks from earthquakes, avalanches, or vehicles.

Oil began flowing on 20 June 1977. Since then over 15 billion barrels (2.4×109 m3) of oil have been pumped, peaking at 2.1 million barrels per day (330,000 m3/d) in 1988 and currently down to 720,000 barrels per day (114,000 m3/d) (April 2008 average) [1]. Around 16,700 tankers had been loaded at the Marine Terminal at Valdez by 2001. The terminal has berths for four tankers and cost almost US$1.4 billion to build. The first tanker to leave the terminal was the ARCO Juneau on 1 August 1977.

Maintenance

The pipeline is surveyed several times a day, mostly by air. Due to the placement of the surveillance bases, the pipeline can be surveyed in just two hours, but most surveys take longer to ensure thoroughness. Other methods of surveying include regular pipeline inspection gauges ("pigs"), sent through the line. Some pigs are used to remove the buildup of kerosene inside the pipe, while others have electronics which relay radar scans and fluid measurements as they travel.

File:Trans Alaska Pipeline Denali fault shift.JPG
Pipeline on slider supports where it crosses the Denali Fault.

The pipeline has been damaged several times. It was built with earthquakes in mind and has survived several, including the 7.9 magnitude quake of 3 November 2002. It is vulnerable to intentional attack and to forest fires. The highest losses from the pipeline were in February 1978, when a deliberate explosion led to more than 16,000 barrels (2,500 m³) leaking out at Steele Creek, near Fairbanks. From 1977 to 1994 there were 30 to 40 spills a year on average. The worst years in terms of number of incidents were 1991 to 1994, when there were 164 spills, although none were major. Since 1995 the number of spills has been sharply reduced, with total losses from 1997 to 2000 totalling only 6.89 barrels (1.10 m³).

The steel pipe is resistant to gunshots, but on 4 October 2001, a drunken gunman named Daniel Carson Lewis shot a hole into a weld near Livengood, causing a spill of about 6,000 barrels (950 m3). [2] [3] Approximately 2 acres (8,100 m2) of tundra were soiled and were removed in the cleanup. The pipeline was repaired and was restarted on 7 October 2001. Lewis, known as a troublemaker in the community of fewer than 30 people, was apprehended four hours after the shooting. He was convicted on multiple state and federal felony charges, including a $10,000 fine and 10-year federal sentence for being a felon in possession of a firearm.

In August 2006, after an inspection mandated by the United States Department of Transportation after a March spill, BP announced they had discovered corrosion severe enough to require replacement of 16 of 22 miles (35 km) of transit pipelines at their Prudhoe Bay oil field.[32] No part of the main Trans-Alaska Pipeline was affected, although Alyeska said that lower crude oil volumes could slow pumping during the BP shutdown.[33]

Wikimedia Commons has media related to Trans-Alaska Pipeline System.

See also

Notes

  1. ^ Banet, p. 27
  2. ^ Leffingwell, E.d. "The Canning River region, northern Alaska: U.S. Geological Survey Professional Paper 109", U.S. Geological Survey. 1919. Accessed June 14, 2009.
  3. ^ Bird, Kenneth J. and Houseknecht, David W. "2002 Petroleum Resource Assessment of the National Petroleum Reserve in Alaska (NPRA)", USGS. 2002. Accessed June 14, 2009.
  4. ^ Naske, p. 256
  5. ^ Naske, pp. 256–257
  6. ^ Gedney, Larry and Helfferich, Merritt. "Voyage of the Manhattan", Alaska Science Forum. December 19, 1983. Accessed June 14, 2009.
  7. ^ Kavanagh, Dave. "S.S. Manhattan & the Northwest Passage", sunshiporg.homestead.com. July 12, 2005. Accessed June 14, 2009.
  8. ^ Naske, p. 252
  9. ^ Mead, p. 118
  10. ^ Naske, p. 251
  11. ^ Berry, p. 106
  12. ^ Naske, p. 253
  13. ^ Naske, p. 255
  14. ^ Naske, p. 257
  15. ^ Cole, p. 17
  16. ^ Coates, p. 185
  17. ^ Coates, pp. 189–190.
  18. ^ Coates, p. 193
  19. ^ a b Coates, p. 196
  20. ^ Coates, p. 199
  21. ^ Coates, p. 203
  22. ^ Coates, p. 200
  23. ^ a b Coates, p. 207
  24. ^ a b Coates, p. 208
  25. ^ Mead, p. 134
  26. ^ Mead, pp. 134–135
  27. ^ Mead, p. 135
  28. ^ Taylor, Susan. "Claims Bill Disappointing: Strong General Note of Dissatisfaction on Latest Claims Bill", The Tundra Times. May 20, 1970. Accessed June 18, 2009.
  29. ^ a b c Mead, p. 136
  30. ^ Mead, p. 137–139
  31. ^ Alyeska Pipeline Service Company. "Pipeline quick facts", alyeska-pipe.com. May 9, 2008. Accessed June 18, 2009.
  32. ^ Pemberton, Mary (8 August 2006). "Gas prices climb as oil pipeline in Alaska must be replaced". The Daily Texan. Retrieved 2006-08-08.
  33. ^ Wesley Loy and Richard Richtmyer (8 August 2006). "Massive repairs: BP admits corrosion control was inadequate, prepares to replace North Slope transit lines". Anchorage Daily News. Retrieved 2006-08-08.

References

  • Alyeska Pipeline Service Co. Alyeska: A 30-Year Journey. Alyeska Pipeline Service Co., 2007.
  • Banet, Arthur C. "Oil and Gas Development on Alaska's North Slope: Past Results and Future Prospects" (PDF). Bureau of Land Management, March 1991.
  • Berry, Mary Clay. Alaska Pipeline: The Politics of Oil and Native Land Claims. Indiana University Press, 1975.
  • Coates, Peter A. The Trans-Alaska Pipeline Controversy. University of Alaska Press, 1991.
  • Cole, Dermot. Amazing Pipeline Stories. Epicenter Press, 1997.
  • Mead, Robert Douglas. Journeys Down the Line: Building the Trans-Alaska Pipeline. Doubleday, 1978.
  • Naske, Claus M. and Slotnick, Herman E. Alaska: A History of the 49th State. University of Oklahoma Press, 1987. Second edition.
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