Oil and Gas at Your Door? (2005 Edition) - Earthworks

NON CONVENTIONAL OIL AND GAS
to produce one barrel of oil, 192 and about 75 % of the bitumen can be recovered from the sand.
2. In situ (i.e., in place) recovery is used for bitumen deposits buried too deeply for mining to
be practical (usually more than 250 feet, and frequently more 1000 feet below the surface).
Recovery involves injecting substances such as steam or hot solvents, which heat up the
sands and cause the bitumen to become viscous enough to be pumped.
After the heavy oils and bitumen are extracted, they are thinned using another petroleum product.
This enables the product to flow through a pipeline. Some upgrading (removal of some substances
and addition of others) also occurs to produce a higher quality crude oil. Upgrading is
responsible for 60 % of the costs, emissions and energy-use involved in the production of synthetic
crude oil from bitumen. 193
At the present time, tar sands are being mined extensively in the Athabasca oil sands in northeastern
Alberta, Canada. Mining operations there produce the equivalent of 350,000 barrels
of crude per day, while in situ methods produce 150,000 barrels per day. In the U.S., small
deposits of tar sands are located in Utah, Kentucky, Kansas, Missouri, California, and New
Mexico, but these are not presently being exploited. 194
In the 1970s, the availability of $88 billion in federal subsidies for synthetic fuel production created
a rush on tar sand development in the Book Cliffs of northern Utah. But when the subsidies
ran out in the early 1980s, the tar sands development ended.
Oil shale, essentially a hybrid of oil and coal, 195 is a fine-grained rock that contains a hydrocarbon
material called kerogen. Similar to tar or oil sands, the recovery of oil from oil shale uses
two primary methods:
1. Mining techniques bring the oil shale to the surface. Oil is then recovered from the oil shale
using retort methods (i.e., heating shale in the absence of air) at temperatures approaching
950° F. This converts kerogen into oil and gas, and yields between six and 50 gallons of oil
per ton of shale.
2. An in situ retorting technique is used where hot gases and air are injected into holes that
have been bored into the underground shale deposit. The kerogen is converted to oil
underground, and is extracted using conventional oil extraction techniques. 196
The largest and some of the richest deposits of oil shales are located in western Colorado, eastern
Utah, and southern Wyoming. If an economic recovery method could be developed, it is estimated
that these deposits alone could yield between 500 billion 197 and 1.5 trillion barrels of
oil. 198 This is a phenomenally large resource, considering that there is general consensus that
current global conventional reserves of oil are approximately 1,000 billion barrels. 199
At today’s petroleum prices, however, oil shale exploitation is not economically competitive with
extraction from conventional reservoirs. 200 During the so-called “energy crisis” of the 1970s,
when the cost of conventional oil soared, interest in mining oil shales also increased. As mentioned
previously, billions of dollars in federal subsidies were offered to encourage nonconventional
fuel production. Several oil shale leases on federal lands in Colorado and Utah were issued
to private companies, large-scale mining facilities were developed on the properties, and experimental
in situ retorting was carried out on one of the lease tracts. The Exxon Corporation went
so far as to begin constructing entire new towns to support their developments, but when petroleum
prices began to fall in the 1980s, their projects were abandoned. Unocal operated the last
large-scale experimental mining and retorting facility in western United States, which closed in
1991. 201 I-39