Vast, hard-to-tap reservoir of oil in Green River Basin shale regains attention
JEFF GEARINO Southwest Wyoming bureau | Posted: Thursday, August 20, 2009 12:00 am
GREEN RIVER - Occasionally throughout history, a really bad idea pops up. Think League of Nations, 8-track tapes, Beta max videos, and the Berlin Wall, to name a few.
Only time will tell if oil shale should be added to the list.
The Rocky Mountain West has up to 1 trillion barrels of oil bound in shale formations up to 1,000 feet thick in northwestern Colorado, southwestern Wyoming and eastern Utah.
Scientists are researching ways to tap into those Western oil reserves that some experts believe could be two or three times as large as Saudi Arabia's oil reserves.
But don't expect much development of this resource anytime soon in the Cowboy State.
Officials involved in the industry say the quality of oil shale deposits will most likely determine where and how oil shale will be developed on a commercial scale.
And since Wyoming's oil shale is not near the quality of Colorado's, the industry is expected to go after the best quality shale first in order to prove up the extraction technologies being developed by the energy industry.
Companies including Shell Frontier Oil and Gas Inc. that have been working on oil shale technology say commercial development anywhere in the West is likely years off.
Shell, for example, has been researching ways to tap oil for more than three decades on private testing lands in Colorado.
"I don't think anybody is talking about oil shale development in Wyoming anytime soon … it may not happen fast in Wyoming," said Tracy Boyd, the communications director and sustainability manager for Shell's Mahogany oil shale research project near Meeker, Colo.
"There are huge reserves out there," Boyd said.
"In the whole Green River formation, they are estimating there is some 800 billion barrels of recoverable oil or more in the shale and that's the driving force behind this," he said. "We want to take our research and move it to a commercial stage."
Long road to development
But opponents of oil shale development have raised concerns about the amount of electricity and water that might be needed to support the renewed oil shale development efforts in the region.
Detractors of oil shale development said it's not the first time that oil shale has been offered up as a cure for America's dependence on foreign oil. They are urging the federal government to move cautiously on oil shale.
Conservationists recalled that the last major push to develop oil shale reserves in the West in the 1970s resulted in Exxon's closure of its $5 billion project near Parachute, Colo., in 1982 amid plummeting oil prices and federal subsidies.
About 2,200 people lost their jobs and whole towns disappeared in what is still known today as "Black Sunday."
"Wyoming has chased an awful lot of energy boondoggles over the years … and oil shale is really one of the biggest boondoggles to come along," said Erik Molvar, a wildlife biologist with the Laramie-based Biodiversity Conservation Alliance.
"It's seems like every 15 years or so the oil and gas industry forgets what a stupid idea it is and decides it wants to chase this mirage," he said. "Spending money on oil shale is a little bit like gambling on a horse with three legs."
Molvar said the good news is that Wyoming's oil shale deposits are thinner and lower-grade than those in Colorado and Utah. "Hopefully, we'll never suffer large-scale impacts from oil shale," he said.
Research projects
Oil companies have struggled for decades to unlock the solid organic material known as kerogen - which releases petroleum-like liquids when heated - from shale sediment layers ranging from surface outcrops to deep underground formations.
The U.S. Bureau of Land Management recently finalized a plan to guide the use of public lands containing oil shale with an eye toward allowing some form of commercial development in the near future.
In 2005, the Bush administration announced plans to accelerate oil shale development in the West by offering industry research sites on small tracts of BLM-administered lands that could be leased to companies as they try to figure out how to economically convert oil shale into fuel.
The agency selected six research and development projects that are currently being used for oil shale research and development activities. The companies include Shell Exploration and Production Inc., Chevron's Shale Oil Co., and American Oil Shale LCC.
Chevron is investigating the possible use of chemistry instead of heat as a means of producing fuel from oil shale. The company is studying the possibility of pumping carbon dioxide under high pressure into underground oil shale deposits to draw out the kerogen fuel from the shale.
The company hopes the process will reduce the amount of energy needed and could produce water instead of consuming it during the oil shale production process.
Boyd said Shell is also researching an "in situ" process at its Mahogany research project that includes trying to heat oil shale underground to free the kerogen.
He said the process involves heating underground oil shale using electric heaters placed in deep vertical holes drilled through a section of oil shale.
The oil shale is heated over a period of two to three years until it reaches a temperature around 700 degrees, at which point oil is released from the shale and the product is gathered in collection wells positioned within the heated zone.
The plan includes the use of ground-freezing technology in which an underground barrier called a "freeze wall" is established around the perimeter of the extraction zone.
Boyd said the freeze wall is created by pumping refrigerated fluid through a series of wells drilled around the extraction zone.
He said the freeze wall is designed to prevent groundwater from entering the extraction area, while keeping hydrocarbons from leaving the project perimeter.
"It literally uses a wall or curtain of ice in a rectangular area to isolate an area of shale that we want to heat," Boyd said. "We're about a year into the process of forming the walls now, and we think things are going well."
Fraught with hurdles
Molvar called current oil shale energy production a "dirty business" that is far worse to the environment than the conventional extraction of fossil fuels.
He charged the process produces massive air pollution, leaves behind toxic chemicals that leach into the water supply, and requires about as much energy to extract as it would produce.
He said oil shale production generates air pollution and causes "some of the worst types of emissions" during the retorting process.
"Oil shale production requires a complete and utter lack of respect for the land," Molvar said. "There is just no way to produce it right now without the complete destruction of the landscape on which you are producing."
Additionally, he said the water demands are huge in oil shale processing.
Molvar said current oil shale methods use seven gallons of water for every gallon of oil produced, while the most advanced methods of conventional oil production at present consume 3.5 gallons of water for each gallon of oil.
"Oil shale production consumes huge, huge amounts of water, and the identified oil shale deposits across the West are all in the Colorado River Basin … and that water is already over-appropriated for irrigation and municipal use," he said.
"Where will all this water come from?"
Molvar said the worst impacts may be to the land itself. He noted traditional oil shale extraction methods could require massive open-pit strip mines up to 2,000 feet deep.
Under Shell's in-situ scenario, Molvar said some 100 wells would be required for every 10 acres to recover the resource. "Thus, 100 percent of the land surface must be bulldozed and flattened," he said.
But Boyd said there has been "literally near hysteria" about the energy and water demands that might be required for full-scale commercial production and whether the return will be worthwhile.
"In the Piceance Basin … we're talking about the most intensely concentrated hydrocarbon resource on the planet that's estimated by the (U.S.) Department of Energy to be somewhere between 1-2 million barrels per acre, which is huge," he said.
"So now (with the research projects) we're trying to limit the uncertainty, to get a better grasp on the technology, and it's a long, slow process," Boyd said.
"It's the unknown and the questions (about water and energy) that are the things we're trying to resolve through this research and development program."
Southwest Wyoming bureau reporter Jeff Gearino can be reached at 307-875-5359 or at gearino@tribcsp.com.