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Why a tiny bit of oil can be a big deal
More than three-quarters of U.S. wells make just 6% of the country's oil. They're called marginal wells because of their small output. But they're a big deal to oil producers and environmentalists.
More than three-quarters of U.S. wells make just 6% of the country's oil. They're called marginal wells because of their small output. But they're a big deal to oil producers and environmentalists.
(Image credit: September Dawn Bottoms for NPR)
