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grounds that budget items must be reconciled with reality. Since
the last elections thinned the ranks of senators opposed to drill-
ing, many watchers expect such plans to move for ward, despite
what ought to be resistance from Democratic senators friendly
to environmentalism, like Barbara Boxer of California and John
Kerry of Massachusetts.
In 2001, as the debate about the refuge was making its near-
yearly round through Washington and the media, members of
Congress were provided with a report from the Congressional
Research Service (CRS) that described the extraction technolo-
gies proposed for use in the refuge. The report, "Arctic Petro-
leum Development: Implications of Advances in Technology," is
for the most part optimistic about the industry s ability to extract
oil while minimizing environmental damage. It was prepared by
Ter ry R. Twyman, a geologist and now a sta member of the
American Petroleum Institute, which represents the interests of
the oil and natural-gas industries.
The CRS describes itself as the "public-policy research arm"
of Congress, charged with providing "nonpartisan, objective
analysis and research on all legislative issues." With a budget of
some $80 million, the CRS maintains a huge sta of analysts who
produce reports on any topic that might be debated, ranging from
problems facing mortgage funder Fannie Mae to homeland se-
curity. Its reports are available only to members of Congress but
often make their way to the public anyway, usually through the
o ces of legislators who feel they stand to bene t from them.
"Arctic Petroleum Development," for example, can be found on
the website of the American Petroleum Institute.
If Terry Twyman, having taken a job at the API, might be con-
sidered pro-oil, that does nothing to diminish the importance of
the report, which more or less represents the industry s best case.
A look at this case may help clarify the issues involved, for anyone
who is following the debate or simply trying to understand what
the refuge may look like to the visitor in 2015.
Ice Roads for Thumper Trucks
When a new oil eld is opened, each phase of its development---
exploration, drilling, and production---may damage the land-
scape, and in each of these phases, technological improvements
promise to reduce or eliminate that damage.
More particularly, exploration, as it is currently conducted,
consists of building a map of subsurface data and then drilling.
Acquiring that data can be disruptive. The crews needed often
number more than 100, and they move across the landscape in
container trains pulled by bulldozers. Depth soundings are initi-
ated by "vibroseis" vehicles, multiton articulated tr ucks lugging
around vibrating plates. The plates generate low-frequency sig-
nals detectable by "geophones," microphones placed in a grid
over several kilometers in rows as close together as a hundred
meters. Sometimes known as "thumper trucks," these vibroseis
vehicles do not produce the portable earthquakes that have agi-
tated the environmental lobby in the past, but they are still sizable
rigs that must cover kilometers of ground within a huge network
of geophones, each of which must be laid by hand.
The damage caused by moving such equipment about can be
minimized, Twyman argues, by exploring the refuge during the
winter, when the terrain is frozen, and using Rolligons, vehicles
with wide, balloon-style tires that would exert no more pressure
on the tundra than a caribou hoof. (One industry photo even
shows a Rolligon rolling over a smiling roughneck.) Coincident
with the advent of the Rolligon has been the increasing use of ice
roads on the North Slope. Ice roads are laid by Rolligons over the
frozen tundra in mid-December and can support larger rigs pull-
ing the mobile homes that house the crew. Drilling pads, too, can
be built of ice. The oil industry contends that frozen roads and
pads make the e ects of exploration nearly invisible---all traces
simply melt away---and believes that it can extend the drilling
season further into spring by insulating the ice platforms.
Proponents also argue that the increasing accuracy of seismic
data---which now yields 3-D rather than 2-D maps and can fre-
quently be analyzed in real time by remote supercomputers---
means that fewer soundings are necessary. The trade-o ,
however, is that although 3-D imaging reduces unnecessary
drilling on what prove to be dry wells, it also requires the em-
bedding of more microphones to obtain information in the rst
place. That, in turn, means more ground covered, with possibly
harmful results. In any case, since the 1980s, advances in explo-
ration technology have cut the number of wells needed to nd
oil in a eld. This is good both for the oil industry s bottom line
and for the environment.
As the CRS report so baldly puts it, though, "there is no sub-
stitute, yet, for drilling," both for testing the hypotheses of com-
puter modeling and for bringing oil to the surface. No substitute,
but the number of wells needed to verify exploration and com-
plete extraction can hypothetically be reduced yet further through
a variety of drilling techniques, including directional, "designer,"
and multilateral drilling.
In directional drilling, extended-reach drills and bits angle
out from a single platfor m to reach widely separated reser voirs
of oil, covering a horizontal distance that can be two to ve times
the wells vertical depth. In the North Sea, such wells have
reached eight kilometers in length. Designer wells use bits that
can make tight turns to avoid obstacles while drilling. Multilat-
eral wells lead several horizontal branches o a single master
well. With 3-D modeling, designer and multilateral wells can
reach smaller and smaller pockets of oil. Drill bits have also im-
proved. Made with diamonds, they have become harder, mak-
ing drilling faster and allowing shorter times on site.
Drill holes, too, have gotten slimmer, which means fewer
"cuttings"---the waste material that surfaces during drilling---and
fewer personnel needed to handle the equipment and the waste.
Some of the associated equipment can be transported by air,
which lessens the need for new roads. A related advance is the
development of coiled-tubing drilling, rst used on the North
Slope in 1991. Where traditional rigs might be 60 meters tall and
use nine-meter-long sections of interlocking pipe, coiled-tube
drilling employs exible pipe that can be carried on a spool
(sometimes brought in by air), which means holes drilled faster
with less equipment and a smaller drilling platform.
Much is made of the "footprint" of an extraction operation---
the area it takes up---and Twyman reports that, overall, that has
been much reduced as well. Drilling, for instance, produces
enormous volumes of by-products, including water, natural gas
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