All booms eventually fade….
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A decade-old congressional mandate to spur investment in renewable fuels has helped turn South Dakota into one of the country’s biggest ethanol producers. But growth is uncertain as opponents of the mandate push for overhaul or repeal of the Renewable Fuel Standard.

Ethanol and corn producers in South Dakota, which is No. 6 in ethanol production in the U.S., say the mandate has created hundreds of jobs and pumped millions of dollars into the state through higher corn prices for farmers, plus taxes and other revenue.