(NEW YORK) -- Drillers in Utah and Colorado are poking into a massive shale deposit trying to find a way to unlock oil reserves that are so vast they would swamp those of the Organization of the Petroleum Exporting Countries, or OPEC.
A recent report by the U.S. Government Accountability Office estimated that if half of the oil bound up in the rock of the Green River Formation could be recovered it would be "equal to the entire world's proven oil reserves."
Both the GAO and private industry estimate the amount of oil recoverable to be 3 trillion barrels.
"In the past 100 years — in all of human history — we have consumed 1 trillion barrels of oil. There are several times that much here," said Roger Day, Vice President for operations for American Shale Oil (AMSO).
But along with the potential for success comes many hurdles. The cost of extracting the Green River oil at the moment would be higher than what it could be sold for. And in an environmental sense, the operation might require so much water it would compete with Denver and agriculture for vital supplies, the GAO report warned. The extraction could pollute underground streams, affect fish and other wildlife, and kick up so much dirt it would leave national monuments in a cloud of dust.
Nevertheless, the federal government has authorized six experimental drilling leases on federal land in an effort to find a way to tap into the riches of the Green River Formation.
GAO's report says commercial development of oil shale is "at least 15-20 years away."
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