How ANWR Works

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ANWR landscape
Image courtesy Jo Goldmann/U.S. Fish & Wildlife Service
Wind River in the Arctic National Wildlife Refuge. This tranquil scene doesn't hint at the controversy the vast refuge has generated. See more oil drilling pictures.

­In 1960, U.S. Secretary of the Interior Fred Seaton set aside 8.9 million acres (3.6 million hectares) in Alaska's northeast corner, calling it the Arctic National Wildlife Range. Seaton did this to protect the region's "unique wildlife, wilderness and recreational values" [source: U.S. Fish and Wildlife Service].

The famed refuge is home to many species of wildlife, including caribou, bears, musk oxen, sheep, wolves, moose and many others. Although the area appears to­ be a barren frozen wasteland during half of the year, it's often described as the "American Serengeti." Little did Seaton know that this wildlife refuge would fuel a heated controversy that remains unresolved to this day.

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­The controversy began in 1968 with the discovery of the largest oil field in North America in nearby Prudhoe Bay. Prudhoe Bay was developed as an oil-producing region, and the Trans-Alaska Pipeline was built to transport this oil down the length of Alaska from Prudhoe Bay all the way to Valdez, Alaska. Reserves of oil also were thought to exist within the Arctic National Wildlife Range at the time.

In 1980, President Carter signed the Alaska National Interest Lands Conservation Act (ANILCA), which doubled the size of the Arctic National Wildlife Range and renamed it the Arctic National Wildlife Refuge (ANWR). This act designated most of ANWR as wilderness and, therefore, protected it from oil and gas exploration. However, one small area remained a remote possibility. Dubbed Area 1002 (after section 1002 of the act), the region was open to exploration only if Congress were to authorize it.

Since 1980, many interested parties have been very curious about that authori­zation, especially since the U.S. Geological Survey estimated in 1998 that the area could contain as many as 16 billion barrels of oil [source: U.S. DOE]. Not surprisingly, Congress has faced numerous calls to authorize oil exploration and development in Area 1002.

Pro-energy groups say that drilling for oil in ANWR will help alleviate America's dependence on foreign oil. Environmental groups oppose disturbing this wilder­ness. This controversy has landed in the center of several presidential and congressional elections. Even Sen. John McCain and Gov. Sarah Palin disagreed on the issue during their 2008 bid for the U.S. presidency and vice presidency.

In this article, we'll explore ANWR's Area 1002, its potential oil reserves and its wildlife. We'll also look at how oil development in ANWR could affect world oil production and U.S. consumption. First, let's get a better picture of this disputed region.



­Sitting in the northeast corner of Alaska above the Arctic Circle, ANWR currently occupies 19.6 million acres (7.9 million hectares). Area 1002 stretches over an approximate 100-mile (161-kilometer) strip of coastal plain, hemmed in to the south by the Brooks Mountain Range, the Beaufort Sea to the north, and the Aichilik and Canning rivers to the east and west, respectively. Area 1002 covers about 1.5 million acres (607,028 hectares), or about 8 percent of the total ANWR area.

Map of ANWR
Image courtesy ­U.S. Fish & Wildlife Service
Area 1002, the northern region shaded light green, is a small percentage of the total area of ANWR that isn't designated as wilderness. (The Kaktovik Inupiat Corporation is Native American land within Area 1002.)

­Ecologically, ANWR is classified as an arctic tundra. Beneath the surface, the ground remains frozen all year round (permafrost). During the summer months, the temperatures rise to an average of about 40 degrees F (4.4 degrees C), and the sunlight shines continuously. The upper few inches of soil thaw, which allows opportunistic plants to establish a foothold and grow. During the winter, the temperatures drop to an average of about -4 degrees F (-20 degrees C), and the days are continuously dark. Little rain falls (less than 10 inches or 25 centimeters per year), and about half the time, the skies are cloudy.

The topography of ANWR soars from the high peaks of the Brooks Mountain Range and swoops down to the low-lying coastal plain along the Beaufort Sea. ANWR's coastal plain region features rolling hills from the coast to the foothills of the Brooks Mountain Range. The area contains many small lakes and rivers that flow northward from the mountains to the Beaufort Sea. The vegetation consists mostly of mosses and shrubs, or plants with shallow root systems that can penetrate the upper layers of thawed soil during the growing season.

The Dinkum Sands Case
In 1997, the state of Alaska claimed that the submerged lands along the northeast coast and the lagoons enclosed by them were under state, not federal, jurisdiction (one of these land formations was called Dinkum Sands). If this were true, then these areas could be explored for offshore drilling of oil and gas. However, the U.S. Supreme Court ruled that these lands and lagoons were part of ANWR and, therefore, owned by the U.S. government. The court also declared the coastal waters off the National Petroleum Reserve Alaska (NPRA) as owned by the federal government. That makes these areas subject to federal protection under the 1980 ANILCA law.

­Numerous species of mammals and birds call ANWR home. Some of the most important species relative to the controversy include caribou, polar bears, musk oxen and various birds. Although polar bears move throughout the north shore of Alaska, many female polar bears make their dens onshore in Area 1002. Porcupine caribou like to migrate to the area to breed and give birth in the spring. Many bird species also head for nesting areas there during the brief spring and summer.

Two groups of native peoples reside within ANWR: the Gwich'in Indians and the Inupiat Eskimos. The Gwich'in Indians live in about 15 villages scattered from Arctic Village, Alaska, southward and westward, extending into Canada. These people live in traditional ways and depend upon the porcupine caribou that migrate and breed within ANWR for subsistence. The Inupiat Eskimos reside along the coastal plain and hunt whales, musk oxen and sheep.

In 1971, President Nixon signed the Alaska Native Claims Settlement Act (ANCSA). This act established the Kaktovik Inupiat Corporation (KIC) and subsequent city of Kaktovik, Alaska, located within Area 1002. Except for the KIC, the land within ANWR including Area 1002 is owned by the U.S. government.

­Now that you know a little more about ANWR's residents, let's talk about the elephant in the room: oil.



In 1998, the U.S. Geological Survey (USGS) examined ANWR's coastal plain, specifically Area 1002, to estimate the amount of technically recoverable oil. Based on the geology, the USGS projected that there could be anywhere from 5.7 billion to 16 billion barrels of oil (average = 10.4 billion barrels). Of this potential oil, 74 percent lies on federal lands, with the remaining oil on state and native lands. So 7.7 billion barrels of oil might be located on the federal portion of ANWR (based on the average numbers). For comparison, the rest of the undiscovered, recoverable oil within the United States is estimated at 120 billion barrels [source: U.S. DOE]. Therefore, the estimated oil within Area 1002 is about 8.7 percent of the total undiscovered, recoverable oil within the United States. Since 1998, there have been no further surveys of ANWR oil.

How does ANWR's oil compare to other Alaska oil fields on the north slope? Its estimated oil reserves fall below Prudhoe Bay's 13.6 billion barrels, but are similar to the National Petroleum Reserve of Alaska's (NPRA's) 10.6 billion barrels [source: U.S. DOE].

Comparison of the 1998 ANWR and 2002 NPRA U.S. Geological Survey assessments.
Volumes are technically recoverable oil.

Oil, millions of barrels

Size of area

Entire area1




(million acres)

ANWR assessment





NPRA assessment





Federal area

ANWR assessment





NPRA assessment





1 includes federal and native lands, as well as state offshore areas; F95 indicates the USGS's more conservative estimate for oil; Me indicates the mean estimate; F05 indicates the USGS's least conservative estimate.

Source: USGS

In 2007, Alaska Sen. Ted Stevens asked the U.S. Energy Information Administration (EIA) to revise its assessments of the potential oil production from ANWR and its impact on oil production, imports and world oil prices. The EIA based its analysis on the USGS estimates within ANWR. The agency projected that it would take a minimum of 10 years from the time oil exploration and drilling in ANWR was approved until oil production could begin (barring any legal challenges).

Uncertain Estimates?
The EIA noted several uncertainties in its projections. For instance, the estimated oil reserves and the size of individual oil fields are not known for sure. In addition, the quality of ANWR oil isn't known but assumed to be similar to nearby Prudhoe Bay. If it were more viscous, it would be harder to extract and production would be lower.

­Why the long delay? For one, oil companies could only drill wells during the winter (a span of three to four months), and heavy equipment could only be transported to and from ANWR drilling sites by ocean barges during the summer (a window of two to three months). Add the time it would take to obtain leases, drill exploratory wells and construct producing wells, and 10 years have slipped by. Under that reasoning, oil production could begin in 2018 if drilling were approved today.

If oil production began around 2018, the EIA anticipates that ANWR oil production would add to U.S. oil production and peak around 2027 or 2028 (most U.S. oil production comes from the lower 48 states and offshore resources). When the EIA considers the mean oil estimate, ANWR would contribute about 2 percent of total U.S. daily oil production in 2020 and increase to about 10 percent of U.S. daily oil production by 2030 (cumulative 2.6 billion barrels of oil from 2018 to 2030).

So what would be the economic impact of opening ANWR to oil production?

  • ANWR oil reserves would represent 0.4 to 1.2 percent of world oil consumption by 2030, so ANWR oil would have little impact on world oil prices.
  • At its peak, ANWR oil would contribute about 0.8 million barrels per day to U.S. oil production, but America would still import about 10.6 million barrels of oil per day.
  • The total amount of money that the United States spent on foreign oil between 2018 and 2030 would be cut by $202 billion (2006 dollars) if ANWR were opened to oil production.
­[source: U.S. DOE]



The environmental impacts of drilling in ANWR are hotly debated by environmentalists and proponents of drilling. Arguments center on the following issues:

  • How will the oil be extracted?
  • What infrastructure must be in place to access the drilling platforms?
  • What area of ANWR will be affected by drilling?
  • How will wildlife be altered?

Let's start with the first issue: oil extraction. If you use conventional oil drilling technology, you drill a well straight down to reach an oil field. For most oil fields, you need many wells to recover the oil because of the size, depth and angle of the field. If this type of vertical oil drilling were to be used in ANWR, opponents say that Area 1002 would be littered with oil drilling platforms. Not so, say proponents of oil drilling. Oil drilling technology has changed. Instead of drilling straight down, newer rigs can access multiple parts of an oil field by using directional drilling.

Oil rig on Prudhoe Bay at sunset
Harald Sund/­Getty Images
The skyline at a nearby oil rig in Prudhoe Bay, Alaska. Will the ANWR skyline look like this in the future?

­Directional drilling uses a small motor that goes into the hole behind the drill. The motor can be remotely operated and send back information to the operator about the rock conditions. The operator can then issue commands to the motor as to which direction to drill. Furthermore, the casings that keep the hole open are flexible. The record for directional drilling is reaching an oil field 6.6 miles (10.6 kilometers) away from the platform [source: Pratt]. The overall impact of directional drilling is that multiple wells can be drilled from the same platform and that smaller platforms can be used. Proponents say that these factors will reduce the impact of oil drilling on the land. But even if you reduce the number of wells, won’t individual oil platforms disturb the tundra beneath?

The tundra surface is frozen almost entirely throughout the year. However, a small upper layer melts during the arctic summer. So, how can you place an oil rig on the surface without disrupting it? One solution is to suspend oil platforms on ice platforms. In this way, the oil rig won't disturb the surface or melt the permafrost. Alternatively, oil companies have been experimenting with the idea of using offshore oil-type platforms on land to reduce the area of the platform that contacts the surface. While these types of platforms may be successful, there's more to an oil rig than the rig itself.

First, for each platform, there must be access roads. Roads are necessary to bring in construction equipment, as well as supplies for the oil rigs and the workers. Building these roads likely would disrupt the tundra. To reduce the impact, access roads are often made of ice, and these roads have been successful in many areas of the Arctic. However, ice roads may be difficult to make in the hilly terrain of Area 1002 and could only be used during winter months. In nearby Prudhoe Bay, some gravel roads have replaced ice ones and may be necessary in Area 1002. Opponents fear that gravel paths would have a larger environmental impact.

­Second, there must be some way to ship the extracted oil from the rig. Pipelines or tanker trucks are the typical methods. How much room will the roads and pipelines take up? Proponents of drilling commonly contend that oil operations will only take up 2,000 acres (809 hectares) compared to the 1.5 million acres (607,028 hectares) of Area 1002 or the 19.6 million acres (7.9 million hectares) of ANWR. However, opponents point out that this figure doesn't include the area ­enclosing the roads or pipelines necessary to access the rigs and transport the recovered oil. Opponents contend that Area 1002 would be despoiled by the "sprawl" of oil platforms and their necessary infrastructure.



Oil spill
Ken Graham/­Getty Images
The Exxon Valdez oil spill washes up on the Alaska shoreline. A major oil spill would devastate ANWR.

­Proponents of ANWR oil drilling point to the fact that wildlife at nearby Prudhoe Bay hasn't been affected significantly since drilling operations started in the 1970s. On the flip side, the National Academy of Sciences published a March 2003 report on the environmental impact of potential ANWR drilling, suggesting that drilling operations in Area 1002 would change migration patterns of bowhead whales in the Beaufort Sea (Inupiat Eskimos hunt the bowhead whales). Other potential ramifications include modifying the distribution and reproduction of caribou herds on which the Gwich'in Indians depend, as well as altering area populations of predators and migratory birds.

Many environmentalists argue that ANWR should be left in its pristine condition. Drilling advocates fire back that native tribes already live there, so the area isn't pristine.

Endangered Polar Bears
In 2006, the U.S. Fish & Wildlife Service proposed that polar bears be included on the Endangered Species list. Because polar bears den within Area 1002, this action would affect oil development within ANWR. However, in May 2008, the polar bear was declared a threatened species by U.S. Interior Secretary Dirk Kempthorne, but special rules were put in place that wouldn't hamper oil exploration on Alaska's north coast.

­Another big argument against drilling is the possibility of a large oil spill. No major spill has occurred ­as a result of Prudhoe Bay operations in decades, but in March 2006, a corroded pipeline dumped 200,000 gallons (757,082 liters) of crude oil onto the tundra at Prudhoe Bay. BP Oil pleaded guilty to a federal misdemeanor over the spill and was fined $20 million [source: Rosen]. In addition, in April 2007, a tanker truck leaked 7,000 gallons (26,498 liters) of diesel fuel onto a frozen pond and the surrounding tundra in Prudhoe Bay [source: Petroleum News]. Oil drilling and extraction aren't clean activities. The worst fear is that an accident on the order of the Exxon Valdez oil spill could permanently devastate the ANWR environment

The controversy over oil drilling in ANWR continues with no resolution in sight. So, what are public opinions on drilling? It depends on whom you ask:

  • Many Alaskans favor ANWR oil drilling as it would strengthen the Alaskan economy and provide jobs.
  • The Inupiat Eskimos are open to drilling, so long as it can be done in an environmentally safe manner and they have say into the process and revenues.
  • The Gwich'in Indians are opposed to drilling in ANWR.
  • During July 2008's high gas prices, the Pew Center found that the U.S. public increasingly favored opening ANWR to drilling -- 53 percent favored it, 43 percent opposed it and 7 percent were undecided [source: Pew Center].

No doubt that as America's oil dependence continues, so will the controversy over whether to drill in ANWR. Ultimately, the decision rests with the U.S. Congress and the political process.

Keep reading for more links on oil, polar bears and Sarah Palin.



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More Great Links


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