What to do with the Arctic National Wildlife Refuge? In the past decade, no single environmental issue has been more explosive. Should it be shielded from the oil industry? Or should a section be opened to extract oil for a hungry economy?
Those policy questions aren't answered here, but below are some answers to background questions to frame the debate among Republicans, Democrats, industry and environmentalists.
What is the Arctic National Wildlife Refuge?
Often referred to by the acronym ANWR, the refuge in northeast Alaska covers 19.6 million acres, an area about the size of South Carolina.
It is home to 45 species of mammals, ranging from the small pygmy shrew to the large bowhead whale. Others include caribou, wolves, Dall sheep, moose, musk oxen and polar, grizzly and black bears. Waters in the refuge are home to 36 species of fish, and 180 species of birds live in or pass through the refuge on their migrations, including snow geese and peregrine falcons.
The U.S. Fish and Wildlife Service, which manages ANWR, says one factor that makes the refuge "a very special place is that, as far as we know, there are no species that should be here but are not, and no species that should not be here, but are. In other words, no species of plant or animal is missing, and no outside species has invaded the refuge."
To the west of the refuge lies Prudhoe Bay and existing oil fields that account for 15 percent of domestic production. Farther west is the National Petroleum Reserve-Alaska, an area designated by Congress for oil production and which the Bush administration is now opening up to exploration. The reserve, Prudhoe Bay and ANWR's coastal plain make up the geographical area known as the North Slope.
Where would ANWR drilling take place?
By law, only a specific area on ANWR's coastal plain may be opened to drilling should Congress vote to do so. Known as the 1002 Area, it covers 1.5 million acres.
Drilling supporters say the total area needed for the drilling facilities would be just 2,000 acres. They also cite technical improvements that have slashed the size of drilling sites.
Environmentalists counter that the 2,000 acres don't take into account the miles of roads and pipeline that would be needed to support each drilling site.
How much oil is thought to be in ANWR's 1002 Area?
The only data for estimates comes from 1984-85 seismic tests done by industry. In 1998, the U.S. Geological Survey went through the data and came up with these estimates for ANWR's 1002 Area:
- Oil: 95 percent probability of 4.25 billion barrels of technically recoverable resources. Five percent probability of 11.8 billion barrels. That comes out to a mean probability of 7.7 billion barrels.
- Natural gas: 95 percent probability of zero technically recoverable resources. Five percent probability of 10 billion barrels. That comes out to a mean probability of 3.5 billion.
Why are environmentalists, and most Democratic lawmakers, against drilling in ANWR?
They see the refuge as a unique ecosystem that's worth protecting. Porcupine caribou cross into the coastal plain from Canada to give birth in the summer months, they note, while muskoxen live there year-round and pregnant polar bears use the coastal area as a den habitat. Snow geese and other migratory birds travel through the refuge as well.
Environmentalists note that whatever oil is there would take a decade to pump out and in any case would not reduce U.S. reliance on foreign supplies by very much. They instead want the government to do more to promote cars that get better mileage and to develop alternative energy sources.
Why do President Bush and most Republican lawmakers favor drilling there?
Energy independence has become an important theme, especially following the Sept. 11, 2001, attacks and amid general instability in the Mideast.
Drilling supporters note that ANWR has the most oil potential of any U.S. onshore area and could shave U.S. reliance on foreign oil. The Energy Information Agency estimates that 62 percent of oil needed in 2020 will be imported, and if the high end of ANWR oil estimates are accurate, the oil from the refuge could reduce that to 60 percent.
If high-end estimates of natural gas are accurate, supporters note, ANWR could produce more than 150 billion cubic feet a year, about what South Carolina uses in the same period.
What impact has Prudhoe Bay drilling had on the area?
At the request of Congress, the National Academy of Sciences convened a panel of experts to study the effects of existing North Slope drilling.
The panel, noting that its findings could be useful in the ANWR debate, issued a report in 2003 that included these conclusions:
- Oil industry and government efforts have reduced many environmental effects, but have not eliminated them.
- Oil spills on the tundra so far have been small, and the damaged areas have recovered.
- Caribou populations have not shown a dramatic decline, but drilling has affected their geographical distribution and reproductive success at times.
- When drilling has ceased, equipment, buildings, roads, pads and other installations will probably remain in place because of the high costs of dismantling and restoration, so some environmental effects are likely to persist.
- Bowhead whales have taken a different route in their fall migration to avoid the noise of seismic exploration. As a result, Inupiat Eskimos, who have been hunting the whales for centuries, have had to travel farther out to sea.
- More people on the North Slope has meant more refuse for scavenging bears, foxes, ravens and gulls. Their numbers have increased, but some of these animals also prey on bird species, some of which are listed as endangered or threatened.
The panel made clear that its task was not to decide whether the economic benefits outweighed the environmental and cultural consequences. "Society as a whole must debate and decide that issue," the panel said.
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