POST INDEPENDENT - 11/16/10 Oil Shale Dreams On Roan Plateau
Nov 16, 2010
by John Colson
Observers in western Colorado, including Garfield County, have been closely watching the increasing corporate and governmental activity aimed at reviving the search for ways to develop oil shale reserves in the region.
According to estimates by the U.S. Department of Energy and the energy industry, the most “economically attractive U.S. deposits — containing an estimated 1.5 trillion barrels [capable of yielding more than 10 gallons per ton of ore]” are found in the Green River Formation in Colorado, Utah and Wyoming.
The richest area, experts agree, is the Piceance Basin in Western Colorado, which encompasses the Roan Plateau. Several companies are now engaged in a race to determine the best way to milk the oil-like substance known as kerogen that is lodged some 2,000 feet down in the deep, compressed sandstone layers. Kerogen was created roughly 50 million years ago as organic matter settled to the bottom of lakes and oceans. In one summary, kerogen is characterized as immature oil and gas, which, if given a few million years longer, could metamorphose into traditional subsurface pools of liquid hydrocarbons.
Industry in the U.S. has tried for a century to figure out how to tap the commercial potential of oil shale, most recently in the oil shale boom of the late 1970s and early 1980s, and the bust that sent the state's economy into a tailspin in 1982.
The companies with current leases — American Shale Oil (AMSO), Shell and Chevron — each have different technologies for getting the fuel out of the rocks, and each is using leased federal land to work the bugs out of the respective technological methods.
Another round of oil shale leasing is now working its way through the U.S. Bureau of Land Management. If approved, the leases are expected to go to Exxon-Mobile, Natural Soda and AuraLite.
Environmental organizations, meanwhile, are lobbying against the new round of leases.
The opposition is based in part on concerns that an oil shale industry would be too water-consumptive, and produce too much pollution of both air and water resources in the region.
As things stand, AMSO is using technology similar to that used by a former lease holder in the same region, which was named American Soda, confusingly enough.
American Soda used heated fluids pumped deep into the earth to dissolve naturally occurring nahcolite, or baking soda, which is found intermingled with oil shale in the Piceance Basin. The pressurized solution is then brought up to the surface for processing into a commercial product.
AMSO, at its lease on the Roan Plateau, hopes to mimic that “in-situ” (meaning in-place) technology to bring shale oil to the surface.
On a recent fly-over of the Roan, pilot Bruce Gordon of EcoFlight pointed out 11 probe sites he believed belong to AMSO, indicating the places where well-bores have been drilled down to the level of the shale.
Chevron, too, hopes to heat up the shale in the ground, but its in-situ procedure uses an injected flow of heated, compressed gases to force the shale oil to rise through special production well bores.
Also active on the Roan is Shell Frontier Oil & Gas, which is believed to be ahead of everyone else and is working on another in-situ process for freeing up kerogen.
Shell's technology calls for a “freeze wall” surrounding the section of ground to be heated, to prevent the heated kerogen-based vapors from migrating into groundwater supplies. The heating process, according to published accounts, is to take three to four years, which some descriptions say “accelerates [the] natural process of oil and gas maturation by literally tens of millions of years.”
High on the Roan Plateau, long the province of mountain lions and bear, deer and elk and the occasional cattle herd, the signs of all this work are clear when seen from a small plane.
Flying over the Roan with EcoFlight, a nonprofit organization known as “the environmental air force,” and Jason Wedemeyer of the Colorado Environmental Coalition, reporters and photographers could see a patchwork of industrial activity.
Scattered gas drilling pads are surrounded by pipeline scars and, in one section, shaved spots where Shell and AMSO had punched their probes down to the geologic layers where oil shale lies.
Ridges and intervening valleys, looking like waves moving in an east-west surge, are sparsely populated aside from the gas rigs and a couple of clusters of industrial structures.
“They're really putting lot of thought into ... how to be carbon neutral,” said Wedemeyer, referring to companies that are investing in gas, oil shale, solar, wind and other ways of generating energy.
The coalition, one of a number of organizations resisting the next round of oil shale leases, is “really concerned about the water impacts ... [and] the wildlife impacts” of heavy industrial activity in places such as the Roan.
Wedemeyer and like-minded others were encouraged when U.S. Secretary of the Interior Ken Salazar, a former senator from Colorado, cut the sizes of the second round leases.
The second round is being held to 160-acre parcels, with potential to expand to 640 acres if warranted by results. This compares to the first round of leases, under George W. Bush, that permitted expansion of up to 5,100 acres.
“We want to see results before we lease off everything else in the Piceance,” Wedemeyer said from the front passenger seat of the single-engine aircraft.
He mused about the current thinking of some industry experts, which is to use natural gas to generate the electricity used to heat the shale, which would put a smaller amount of greenhouse gases in the air than with coal-fired power plants.
“Some of that is actually good,” he said of the industry's interest in nontraditional thinking, although he worried about the amount of energy needed to produce a barrel of shale oil.
“We're talking about huge amounts of energy to get oil shale out of the ground,” he said.
Industry experts have conceded that oil shale production is energy intensive, but maintain they expect to get the ratio of energy spent, versus energy gained, to a commercially viable level.
But Wedemeyer and others advise a cautious, slow approach.
“Let's not put all our chips in the pot on something that hasn't been proven,” he declared.