Encyclopedia of Global Resources part 11 pdf

Most com-mon uses of asbestos—applications such as pipeline insulation, clothing, and roofing felt—were banned in the United States in 1990, and virtually all asbestos products were bann

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with other fibers and spun or milled into cloth The

shorter, or “nonspinning,” fibers are generally made

into compressed, molded, or cast products, such as

as-bestos pipe and sheet, in which the fibers are added to

a binder such as portland cement or plastic Such

products account for most of the asbestos produced

each year Of the six different minerals that have been

produced as asbestos, only crocidolite and amosite

have been produced in important quantities

Produc-tion of anthophyllite, tremolite, and actinolite has

been extremely limited and was nonexistent by the

end of the twentieth century

Uses of Asbestos

Although the individual properties of asbestos

miner-als differ from one another, they share to varying

de-grees several properties that make them useful and

cost-effective These include nonflammability, great

resistance to heat and acid attack, high tensile strength

and flexibility, low electrical conductivity, resistance

to friction, and a fibrous habit

Over a span of only a few years, the public’s view of

asbestos changed dramatically: Once considered a

useful commodity, asbestos became known as an

ex-tremely dangerous material The change began with

passage of the Clean Air Act (1972), which classified asbestos as a carcinogenic material because studies of workers exposed to high concentrations of asbestos dust for many years showed a high incidence of asbes-tosis, a lung disease that decreases the ability to breathe, and mesothelioma, a cancer of the lungs Then, in 1973, a lawsuit against a number of asbestos manufacturers on behalf of an asbestos worker was decided against the companies Litigation mounted, and, in 1982, manufacturer Johns-Manville filed for bankruptcy in the face of overwhelming litigation; eventually, as a compromise measure, the company established a $2.5 billion fund to pay future asbestos claims

Widespread publicity concerning asbestos hazards led to a near hysteria among the general public; many people were afraid to send their children to a school unless asbestos insulation had been removed People brought lawsuits demanding that asbestos be re-moved from public buildings The courts awarded large damage rewards based on the argument that low-level exposure to asbestos should be considered dangerous because a safe level of exposure had not been scientifically established This led to the “single fiber” concept—that exposure to only one fiber of as-bestos may be deadly—in keeping with a widely held public perception that there should be no exposure

to carcinogenic materials in the environment The

“asbestos scare” was largely the result of mass media sensationalism and resultant political and legal pres-sure rather than the result of scientific investigation For example, very few people realized that, according

to scientific estimates, a person breathing normal out-door air inhales nearly 4,000 asbestos fibers per day,

or more than 100 million over a lifetime

Asbestos can be a health hazard, but the serious-ness depends on the length of exposure, the amount

of asbestos in the air, and the type of asbestos involved The danger to miners and others working with asbes-tos in unprotected conditions is demonstrable, but the danger to the general public from minimal expo-sure has been greatly exaggerated Some researchers believe that the danger is so small as to be virtually

nonexistent Melvin Benarde in Asbestos: The Hazard-ous Fiber (1990) outlined the statistical risks (the

num-ber of deaths expected per 100,000 people) for a number of potential hazards The risk of dying from nonoccupational exposure to asbestos is one-third the risk of being killed by lightning and nearly five thousand times less than the chance of dying in a car

U.S End Uses of Asbestos,

1977 vs 2003

Metric Tons

Coatings & compounds 32,500 1,170

Insulation: electrical 3,360 —

Packing & gaskets 25,100 —

Source: Data from the U.S Geological Survey.

Note: U.S mining of asbestos ended in 2002.

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accident Nevertheless, by the mid-1990’s more than

$35 billion had been spent on asbestos abatement in

rental, commercial, and public buildings Most

com-mon uses of asbestos—applications such as pipeline

insulation, clothing, and roofing felt—were banned

in the United States in 1990, and virtually all asbestos

products were banned in the country by 1996

It has been estimated that in the time period from

1965 to 2029 there will be 432,465 asbestos-related

cancers in the United States Although this figure has

been disputed by some epidemiologists and other

ex-perts, it is enough to indicate the misery that many

will suffer because of their exposure to asbestos

Nev-ertheless, the litigation-centered approach to

asbes-tos issues in the United States has been criticized In a

2003 report, the Manhattan Institute’s Center for

Le-gal Policy described asbestos litigation as the

longest-running mass tort in the history of the nation and

arguably the most unjust Some critics have claimed

that the massive asbestos tort litigation is more likely

to enrich lawyers than relieve victims The Manhattan

Institute estimated that of the $70 billion paid out by

companies for asbestos claims, $40 billion has gone to

plaintiffs and defense lawyers Numerous companies

have been driven into bankruptcy by asbestos lawsuits,

some of which had only a tangential connection to the original asbestos exposure Of the twenty-nine com-panies that filed for bankruptcy in the years from 2000

to 2002 because of asbestos litigation, six were valued

at more than $1 billion These included such indus-trial giants as Owens Corning, W R Grace, and U.S Gypsum As the companies that directly produced as-bestos have gone under, plaintiffs’ lawyers have in-creasingly sued companies outside the asbestos and building products industry Companies in more than one-half of all industries in the United States have been sued over asbestos With the total eventual cost

of asbestos litigation estimated at $200 billion, Con-gress has considered several proposals to establish a compensation fund in place of litigation In 2004, in-dustrial states such as Michigan and Ohio enacted measures to implement some form of asbestos tort re-form

Although asbestos use has become rare in devel-oped countries, the same cannot be said of develop-ing economies In most of Europe and North Amer-ica, use of asbestos is strictly limited or banned by law However, emerging nations have continued and even increased the use of asbestos in manufacturing and building Countries such as China, India, Brazil, Iran,

Data from the U.S Geological Survey, U.S Government Printing Office, 2009.

220,000

175,000

380,000

300,000

925,000

100,000

Metric Tons

1,050,000 900,000

750,000 600,000

450,000 300,000

150,000 Zimbabwe

China

Canada

Brazil

Kazakhstan

Russia

Other countries 75,000

World Mine Production of Asbestos, 2008

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and South Korea are major consumers of asbestos

As-bestos mining is widespread in Africa Many

develop-ing nations consider the low cost and the effectiveness

of asbestos as an industrial material to outweigh the

health risks The adverse effects of asbestos as an

in-dustrial pollutant are below the surface and

long-term Many of these nations face a more obvious

health risk from such epidemics as HIV/AIDS,

chol-era, tuberculosis, and malaria, which have been

linked to poverty or inadequate infrastructure

Like-wise, many developing nations have accepted a great

deal of air, water, and ground pollution as the price of

accelerating the growth of fragile economies

Asbes-tos has apparently been accepted as another

pollut-ant Certainly these countries lack the extensive and

ubiquitous legal and regulatory system of the United

States that has focused attention on asbestos

How-ever, in some African nations, such as South Africa

and Swaziland, compensation for workers suffering

the effects of asbestos has been provided

China is perhaps the most dynamic and

fastest-growing of all emerging markets Many have

specu-lated that China will emerge as the most important

economy of the twenty-first century It is worth noting,

therefore, some facts about asbestos consumption in

China China continues to make extensive use of

as-bestos Production of asbestos in China has remained

steady since 1995 China is one of the five leading

pro-ducers of asbestos but is perhaps its leading consumer

Imports of asbestos to China rose from 1,083 metric

tons in 1990 to 145,425 metric tons in 2003, an

in-crease nearly 150-fold Estimates indicate that more

than 100,000 workers in China are exposed to asbestos

Although the Chinese government has official

poli-cies against pollutants, they are often not enforced

With the United States and China taking such

dif-ferent approaches to the use of asbestos, it is not yet

possible to speak of a unified world approach to this

industrial product Certainly its use, associated health

risks, and remediation represent one of the most

im-portant confluences of industry, medical concerns,

and law in the world economy

Gene D Robinson, updated by Howard Bromberg

Further Reading

Carroll, Stephen, et al Asbestos Litigation Santa

Monica, Calif.: Rand Corporation, 2005

Castleman, Barry Asbestos: Medical and Legal Aspects.

5th ed New York: Aspen, 2005

Chatterjee, Kaulir Kisor “Asbestos.” In Uses of

Indus-trial Minerals, Rocks, and Freshwater New York: Nova

Science, 2009

Craighead, John E., and Allen R Gibbs, ed Asbestos and Its Diseases New York: Oxford University Press,

2008

Deffeyes, Kenneth S “Asbestos.” In Nanoscale: Visual-izing an Invisible World Illustrations by Stephen E.

Deffeyes Cambridge: Massachusetts Institute of Technology Press, 2009

Dodson, Ronald, and Samuel Hammar, eds Asbestos: Assessment, Epidemiology, and Health Effects Boca

Raton, Fla.: CRC Press, 2005

Guthrie, George D., Jr., and Brooke T Mossman, eds

Health Effects of Mineral Dusts Washington, D.C.:

Mineralogical Society of America, 1993

Harben, Peter W., and Robert L Bates Industrial Min-erals: Geology and World Deposits London: Industrial

Minerals Division, Metal Bulletin, 1990

Kogel, Jessica Elzea, et al., eds “Asbestos.” In Indus-trial Minerals and Rocks: Commodities, Markets, and Uses 7th ed Littleton, Colo.: Society for Mining,

Metallurgy, and Exploration, 2006

McCulloch, Jock, and Geoffrey Tweedale Defending the Indefensible: The Global Asbestos Industry and Its Fight for Survival New York: Oxford University

Press, 2008

McDonald, J C., et al “The Health of Chrysotile

As-bestos Mine and Mill Workers of Quebec.” Archives

of Environmental Health 28 (1974).

Maines, Rachel Asbestos and Fire: Technological Trade-offs and the Body at Risk New Brunswick, N.J.:

Rutgers University Press, 2005

Skinner, H Catherine W., Malcolm Ross, and Clifford

Frondel Asbestos and Other Fibrous Materials: Miner-alogy, Crystal Chemistry, and Health Effects New York:

Oxford University Press, 1988

Web Sites Manhattan Institute Center for Legal Policy Trial Lawyers Inc.: Asbestos

http://www.triallawyersinc.com/asbestos/asb01.html U.S Geological Survey

Asbestos: Statistics and Information http://minerals.usgs.gov/minerals/pubs/

commodity/asbestos U.S Geological Survey Mineral Commodities Profiles—Asbestos http://pubs.usgs.gov/circ/2005/1255/kk

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See also: Clean Air Act; Health, resource

exploita-tion and; Hydrothermal soluexploita-tions and

mineraliza-tion; Metamorphic processes, rocks, and mineral

de-posits; Silicates

Asphalt

Category: Products from resources

Where Found

Before the growth of the petroleum industry in the

early twentieth century, when asphalt began to be

mass-produced, naturally occurring asphalt was

found in pools of petroleum-heavy deposits, most

no-tably Trinidad’s 46-hectare Pitch Lake (off the coast

of Venezuela), the 4,000-hectare Bermudez Lake in

Venezuela, and areas around the Dead Sea basin in

Is-rael and Jordan

Primary Uses

Asphalt is most associated with road-surface paving

Apart from highway construction and repairs, asphalt

is used for airport runways, running tracks, and

drive-ways In addition, asphalt is a waterproofing agent in

fabrics, irrigation systems, roofing shingles, jetties

and sea walls designed to combat beach erosion, and

insulation More than 60 billion metric tons of

manu-factured asphalt are used annually in the United

States alone

Technical Definition

Asphalt is a by-product of petroleum refining, either

occurring naturally over geologic eras or processed

industrially in the controlled refining process called

fractional distillation that occurs once naphtha,

gaso-line, and kerosene have all been extracted from the

crude It is difficult to define a single chemical profile

because asphalt varies depending on the grade of

crude petroleum and the type of refining production

used Generally, asphalts contain saturated and

unsat-urated aliphatic compounds (organic compounds

whose carbon atoms configure in open branches

rather than closed rings) and aromatic compounds

(organic compounds whose carbon atoms configure

in closed rings) with up to 150 carbon atoms Asphalt

contains about 80 percent carbon, 10 percent

hydro-gen, and 6 percent sulfur with trace amounts of

oxy-gen and nitrooxy-gen Molecular weight varies These

compounds are further classified by their solubility— more insoluble compounds are called asphaltenes and less soluble compounds maltenes

Description, Distribution, and Forms Asphalt is a dark (brown or black), cementitious (highly adhesive) material Its predominant elements are bitumens, solid and/or semisolid high-molecular-weight hydrocarbons Because more than 80 percent

of commercially produced asphalt is used for paving, the properties of asphalt are graded according to its performance as a pavement adhesive, particularly how well it holds up over time, specifically in the areas

of aging, stiffening, and cracking

Only 5 percent of the asphalt used today is natu-rally occurring Its most prominent natunatu-rally occur-ring site is Pitch Lake in the petroleum-rich southwest corner of the island of Trinidad, near the town of La Brea Although difficult to determine dimensions with any accuracy because it grows and shrinks, this

“lake”—it is more accurately a sludgy 40-plus-hectare mineral deposit created by a slow underground seep-age of asphalt, or pitch—is estimated to be more than

35 meters across and 107 meters deep at its deepest point (the edges of the lake are crusty and support weight, but toward the center of the lake, the pitch becomes characteristically sticky and far more hazard-ous, easily swallowing entire objects) Given its dimen-sions, the lake has provided an apparently inexhaust-ible supply of asphalt for centuries—large holes left

by removing asphalt are quickly filled in as the lake maintains a kind of fluid dynamic Western explorers were fascinated by the phenomena of this vast tar lake, not merely for the usefulness of the asphalt (they im-mediately used it to upgrade the waterproofing on their ships) but because the lake also preserved the re-mains of prehistoric mammals and birds

Commercially produced asphalt is primarily a taffylike binder known as asphaltic concrete Asphal-tic concrete, a tacky, ductile resin suspended in an oily medium, maintains the integrity of aggregate parti-cles Because asphaltic concrete is highly sticky, it must be heated into liquid to be used for pavement construction It is most often sprayed on a graded roadbed It is then compacted into the proper density, usually 25 to 30 centimeters Because it solidifies into

a tough and flexible surface able to maintain its integ-rity against both the weight and frequency of traffic and the deformations from weather conditions (nota-bly ice and extreme heat), asphalt remains the

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mary roadway surface Given the diminishing supply

of fossil fuel and concerns over the depletion of that

resource, asphaltic concrete is attractive because more

than 80 percent of removed asphalt can be recycled

for new road projects

History

Asphalt was used as early at 3600 b.c.e by the

Sumer-ians as a mortar adhesive for paving and building and

as a waterproofing agent in canal construction and

public pools (records indicate it also was used for

medical treatments, statuar y enhancement, and

mummification throughout the Middle East) Pitch is

mentioned early in the Bible: It binds Noah’s ark and

later makes waterproof the bulrush basket in which

the baby Moses is set adrift on the Nile

Following the discovery of huge natural deposits of

pitch in South America in the fifteenth and sixteenth

centuries (notably by Sir Walter Ralegh), asphalt

be-came a commercially viable waterproofing agent for

the burgeoning shipbuilding industry Not until 1870,

however, was asphalt first tested for paving The idea

came from accounts discovered among Incan archives

dating back to the twelfth century A stretch of streets

in Newark, New Jersey, was made of Trinidad asphalt Its appeal was evident—it was cheap to import, easy to apply, flexible, and once hardened made for a smooth ride Within six years, asphalt was selected for a most ambitious—and prestigious—paving project: Penn-sylvania Avenue in Washington, D.C By the turn of the century, more than 35 million square meters of streets in America were asphalt With the rise of the oil industry, however, commercially produced asphalt became more profitable

Obtaining Asphalt Asphalt may be obtained directly from sludgy beds near petroleum fields However, far more asphalt is obtained as a small fraction of residue distilled during the refining process of crude oil Heavy crude oil is heated to nearly 370° Celsius in large furnaces As the crude is processed, lighter components vaporize and are released into the atmosphere through refinery towers (in the early 1980’s, facing pressure from envi-ronmental groups, the petroleum industry over-hauled the distillation towers to minimize pollution)

To render the remaining asphalt into asphaltic ce-ment, the residue is distilled further through a

Russian workers repave an asphalt road on the outskirts of Abakan (Kolbasov Alexander/ITAR-TASS/Landov)

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uum process designed to prevent the residue from

cracking, and then it is mixed with the appropriate

ag-gregate materials, most commonly crushed rock, slag,

sand, and/or cement stone In turn, the asphalt must

be stored (and transported) at a constant 65.55°

Cel-sius to ensure liquidity If the asphalt must be

trans-ported a considerable way, kerosene or diesel oil can

be temporarily added and then separated before the

asphalt is applied to the roadbed

Uses of Asphalt

Long before the automobile made highway

construc-tion a pressing concern, as thousands of kilometers of

roadway needed to be laid quickly and economically,

asphalt was valued because it was waterproof It

revo-lutionized the shipping industry because of its

caulk-ing ability Even in modern society, asphalt helps

so-lidify sea walls to protect against the effects of tides,

waves, and harsh weather In addition, asphalt lines

the retaining tanks in industrial fish hatcheries,

pre-serves the integrity of irrigation systems (before

as-phalt, up to one-third of water transported would be

lost in transit), and maintains holdings by providing

underlining for reservoirs Furthermore, asphalt has

become a primary liner for the disposal of hazardous

waste and a liner at landfill sites

In addition, because it is waterproof and fire

retar-dant, asphalt can be used, when combined with felt

and mineral granules, to produce the familiar

rectan-gular roofing shingles This asphalt is slightly harder

than paving asphalt (it is typically heated at a much

higher temperature to make it less flexible) Asphalt

shingles are remarkably adaptable to a variety of

roof-ing needs and styles; shroof-ingles can be adjusted for the

slope of the roof, climate conditions, and even house

design

However, asphalt is best known as a paving agent It

is durable, tough, and flexible enough to provide a

comfortable riding surface Industry standards

mea-sure durability of standard asphalt roadways at fifteen

to twenty years That longevity is most often

compro-mised by cracks from water seeping into the surface

during the winter, freezing, and then cracking the

up-per layers or by ruts that appear during hot summers

when the asphalt softens However, asphalt provides

for relatively easy repairs The durability of asphalt,

particularly its capacity to hold up under constant

traffic and enormous weights, has made it the

pri-mary coating for airplane runways For much the

same reason, asphalt is also used for railroad beds and

even subway system track beds Finally, asphalt is used for smaller, high-volume traffic surfaces such as walk-ing trails, tennis courts, bikwalk-ing paths, runnwalk-ing tracks, basketball courts, golf-cart paths, and playgrounds Users of these recreational surfaces appreciate the give in asphalt, as compared to concrete surfaces In

1986, the National Center for Asphalt Technology (NCAT) was established at Auburn University to de-velop asphalt production quality

Joseph Dewey

Further Reading

Karnes, Thomas L Asphalt Politics: A History of the Amer-ican Highway System Jefferson, N.C.: McFarland,

2009

Lavin, Patrick Asphalt Pavements: A Practical Guide to Design, Production, and Maintenance for Engineers and Architects London: Spon Press, 2003.

Nicholls, Cliff Asphalt Surfacing: A Guide to Asphalt Surfacings and Treatments Used for the Surface Course of Road Pavements London: Spon Press, 1998 O’Flaherty, C A Highways: The Location, Design, Con-struction, and Maintenance of Road Pavements 4th ed.

Oxford: Butterworth-Heinemann, 2002

Web Site National Center for Asphalt Technology http://www.eng.auburn.edu/center/ncat See also: Petroleum refining and processing; Renew-able and nonrenewRenew-able resources; Transportation, energy use in

Aspinall, Wayne

Category: People Born: April 3, 1896; Middleburg, Ohio Died: October 9, 1983; Palisade, Colorado

Aspinall, a Colorado Democrat, served in the U.S Congress from 1948 to 1972 From 1958 to 1972, he chaired the House Interior and Insular Affairs Com-mittee, shaping some of the most important natural re-source legislation in American history.

Biographical Background Wayne Norviel Aspinall’s shadow looms large over the modern American West After growing up near

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sade, Colorado, on the Grand (now Colorado) River,

Aspinall attended Denver University, served in World

War I, became a schoolteacher, obtained a law degree,

and ran a peach orchard business Always active in

lo-cal Democratic Party politics, he served as a state

rep-resentative and senator for sixteen years before he was

elected to Congress in 1948

Aspinall quickly made a name for himself as an

ex-pert on public land and federal reclamation issues In

1958, he began chairing the House Interior and

Insu-lar Affairs Committee, a post he did not relinquish

un-til after his defeat in the 1972 Colorado primary

Dur-ing Aspinall’s twenty-four-year congressional career,

his name became synonymous with some of the most

notable legislation that shaped the landscape of the

American West, including the Upper Colorado River

Storage Act (1956), the Wilderness Act (1964), and

the Colorado River Basin Act (1968) From 1964 until

1970, he chaired the Public Land Law Review

Com-mission, which made dozens of recommendations for

reforming the management of the nation’s federal

lands

Impact on Resource Use

By the mid-1960’s, Aspinall’s strict adherence to a

multiple-use philosophy of resource management

had made him a target for environmentalist criticism

In 1970, political columnist Jack Anderson labeled

Aspinall the environmentalists’ “most durable foe”

and accused him of defending timber, oil, cattle, and

chemical interests “against the beauty of American

nature.” To Aspinall, nature had been placed in the

stewardship of humankind, and while he appreciated

the American West’s beauty, he always favored the

controlled use of its resources over what he saw as the

program of “extreme” environmentalists who, in his

view, wanted to “lock up” the region’s resources

Steven C Schulte

See also: Bureau of Reclamation, U.S.; Dams; Energy

politics; Irrigation; Public lands; Wilderness Act

Astor, John Jacob

Category: People

Born: July 17, 1763; Waldorf, near Heidelberg,

Germany

Died: March 29, 1848; New York, New York

Astor, a leader in early American capitalism, founded the American Fur Company, considered the first Amer-ican business monopoly Astor’s astounding financial success, although atypical, pointed to the fortunes that could be made from the exploitation of resources in the young and resource-rich United States.

Biographical Background

As a young man aboard a ship from Germany, John Ja-cob Astor learned about the lucrative fur trade in North America In 1786, three years after arriving in New York City, he opened a fur-goods store and began dealing directly with American Indians to secure his furs In 1796, as his area of activity expanded, Astor se-cured a charter from the British East India Company This charter opened foreign markets, especially the rich fur market of China

John Jacob Astor earned most of his multimillion-dollar fortune in the fur trade (Library of Congress)

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Impact on Resource Use

Astor established the American Fur Company in 1808

In 1811, in an attempt to gain control of fur trade in

the Northwest, he founded the town of Astoria in

Ore-gon However, this plan failed when the British

cap-tured Astoria during the War of 1812 The setback was

temporary, and by 1827, Astor had obtained his

mo-nopoly of the American fur trade

Astor’s trading empire benefited from his

friend-ship with U.S presidents such as Thomas Jefferson,

who appointed Astor executive agent in the

North-west An Astor ship was also allowed to go to China

during the Embargo Act of 1807, producing a profit

of $200,000 Exploitation of human and natural

re-sources was the inevitable result of Astor’s activities

American Indians, to whom the profit motive was

hitherto unknown, were exploited because of their

skill in obtaining animal furs The tremendous

popu-larity of furs led to exploitation of the animals from

which furs were obtained

In 1834, Astor retired from the fur-trading business

to concentrate on investments in New York City His

estate, worth $20 million when he died, made him

the wealthiest person in the United States He left

$400,000 to establish the Astor Library, now part of

New York City Public Library

Glenn L Swygart

See also: Capitalism and resource exploitation;

En-dangered Species Act; Forests; United States;

Wild-life

Athabasca oil sands

Category: Energy resources

Where Found

The Athabasca oil sands are located in the Athabascan

basin of northeastern Alberta, Canada, near the

Sas-katchewan border The Athabasca River runs through

the region—hence its name With two smaller oil sand

deposits located elsewhere in the province, Alberta

has a total of about 140,200 square kilometers of oil

sands, the largest quantity in the world There are also

oil sands located outside Canada, primarily in

Vene-zuela

Primary Uses With industrial processes, bitumen can be extracted from the oil sands and upgraded into light crude oil Although the First Nations (Canadian aborigines) used the tarlike substance to waterproof and patch their boats, in modern times the oil sands have one commercial use: the production of crude oil To pro-duce crude oil, an energy-intensive process is re-quired to extract the bitumen from the thick, sludgy, sandy substance Bitumen is a heavy, viscous oil that can be industrially upgraded into synthetic crude oil, which in turn is refined into gasoline and diesel fuels

Technical Definition The Athabasca oil sands consist of a tarlike mixture of about 80 to 85 percent sand and rich mineral clays, 10

to 12 percent bitumen, and 4 to 6 percent water The valuable resource in this mixture is the bitumen Bitu-men is a heavy, black, asphaltlike substance that has been pressurized underground for millions of years but not long enough to be concentrated into coal or light sweet crude oil Nonetheless, it is a form of crude oil that can be processed for commercial use Tech-nically, bitumen is a mix of petroleum hydrocarbons with a density greater than 960 kilograms per cubic meter

Description, Distribution, and Forms Oil sands are a viscous mix of hydrocarbons and can

be found throughout the world but most prevalently

in Alberta, Canada While the Athabasca region has the largest quantity of oil sands, and the only surface quantities, there are also deposits buried in the Peace River and Cold Lake regions of Alberta (Although the United States has some oil sand deposits, it also has massive quantities of oil shale, rocklike forma-tions containing crude oil that can also be refined at high industrial cost.) The oil sands contain a mix of sands, clays, water, and bitumen, but the bitumen, a form of heavy crude oil, is what gives oil sands their distinctive properties Many ancient cultures made use of bitumen for its sticky, adhesive qualities It was used as a sealant for boats, a building mortar, and an ingredient for mummification In modern times, bi-tumen is valuable as a crude oil that can be refined into commercial petroleum The Athabasca basin has the largest reserves of naturally occurring bitumen in the world Semisolid at normal temperatures, the bi-tumen must be heated or diluted with hydrocarbons

to make it flow through supply pipelines The

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men is extracted through a steam separation process.

Hot water is injected into the mined oil sands, causing

the bitumen to float to the surface, where it can be

re-covered The bitumen is then upgraded into synthetic

oil and petroleum products

History

The First Nations knew about the oil sands deposits

from ancient times and used the tarlike material to

bind their canoes Early Canadian explorers such as

Peter Pond and Alexander Mackenzie wrote of the

fluid bitumen pooling near the Athabasca River In

1882, geologist Robert Bell surveyed the basin and oil

fields However, oil production did not become

possi-ble until Karl Clark first developed a process for

sepa-rating the bitumen from the sands Clark’s process,

developed between 1922 and 1929, relied on hot

water and steam to turn the sand into a soupy

sub-stance from which the bitumen could be extracted

In 1930, the Canadian government leased a large

portion of the Athabasca basin for development to

petroleum engineer Max Ball and his Abasand Oils

company Abasand’s separation process was primitive,

however, and even by the 1940’s Abasand processed

less than 20,000 metric tons of sand per year

The technological challenges of extraction

re-mained daunting, but in the 1960’s the Great

Canadian Oil Sands (GCOS) company built the first

large-scale oil sands production plant, capable of

pro-ducing about 24,000 barrels of synthetic crude oil per

day GCOS eventually became the Suncor Oil

Com-pany, which remains the leading oil producer in the

Athabasca region In 1978, prompted by the oil

em-bargoes of the 1970’s, the Syncrude consortium of oil

companies built a second major oil sands plant,

fol-lowed by Imperial Oil’s Cold Lake plant in 1987,

Alsands Project Group’s facility in 1988, and Shell’s

Albian Sands mine in 2003 In the twenty-first century,

oil production increased, with new technologies

re-ducing the cost of bitumen extraction Dozens of oil

companies and industrial consortiums opened plants

and increased supply The proven feasibility of oil

sands production led the U.S Department of Energy

to tabulate 32 trillion liters of oil reserves in the basin,

second only to the reserves of Saudi Arabia

Obtaining Oil Sands

The bulk of the oil sands are located near the surface

and can be obtained through massive open-pit

min-ing operations Because of the heavy mineral clays

that make up most of the sand, the operations use the largest shovels and trucks in the world to dig up and move the sands Deposits that are located deeper— below 75 meters—are recovered by in situ methods, which include cyclic steam stimulation and steam-assisted gravity drainage About 75 percent of the valuable resource, the bitumen, is obtained during the recovery After the sand is processed and the bitu-men removed, Canadian environbitu-mental laws require the processed sand to be returned to the pit and the site restored to its original condition

Uses of Oil Sands The Athabasca oil sands represent one of the great oil reservoirs in the world Containing a potential 300 bil-lion barrels of crude oil, the oil sands of Alberta, rep-resenting 15 percent of the world’s oil, are second only to Saudi Arabia as potential oil reserves There are currently four thousand agreements in Alberta between Canadian governments and oil companies for production of oil More than 1 million barrels of oil are produced a day Because of the thickness of the oil sands, it takes a tremendous amount of energy to produce oil flow In the winter, temperatures in the Athabasca region fall to as low as−40° Celsius and the extraction machinery can easily freeze up and break down Massive amounts of surface material are moved, sifted, and heated Thus, two major issues must be ad-dressed for the world to exploit this resource: first, the high cost of extraction and, second, the impact on the environment

The profitability of the oil sands depends directly

on the price of oil While light crude oil flows easily from conventional oil wells, oil sand producers must expend fixed costs for mining and extracting the bitu-men and converting it to liquid crude Thus the oil sands may be profitable if the price of oil is more than fifty dollars per barrel, for example, but noncompeti-tive below fifty dollars per barrel and completely un-feasible below thirty dollars With new technology, production costs have been lowered to about thirty-three to thirty-seven dollars per barrel, spurring an oil sands boom As to the environment, the massive pro-cessing of oil sands is bound to leave a certain scarring

of the earth, despite Canadian restoration legislation Oil sands production releases carbon dioxide, which

is believed to contribute to the greenhouse effect The recovery of bitumen itself requires the consump-tion of tremendous amounts of resources, mostly in the form of natural gas and water

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In 2003, with the rise of oil prices, the oil sands

op-eration became consistently profitable for the first

time, and the three major mines—Suncor, Syncrude

Consortium, and Shell Canada—began producing

about 1.2 million barrels of synthetic crude oil per

day It was estimated that production could grow

within a decade to more than 3 million barrels per

day, making Canada one of the world’s leading

oil-producing countries in the world The oil companies

engaged in the major production of oil from the

Athabasca region include Suncor, Imperial Oil, Petro

Canada, Marathon, Chevron, Occidental Petroleum,

Canadian Natural Resources, Shell Canada, EnCana,

British Petroleum, Husky, Total, UTS, Teck, Conoco

Philips, Japan Canada Oil, Devon Energy, and various

joint ventures Cumulative investment in oil sands

production in the first decade of the twenty-first

cen-tury was estimated to be about $70 billion, resulting in

about 275,000 jobs As of 2009, royalties to the

Cana-dian government were close to $3 billion a year and

oil sands production accounted for about 44 percent

of Canada’s total output of crude oil

Howard Bromberg

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