Study: Appalachian coal ash filled with rare earth elements Raleigh, N.C. (UPI) May 27, 2016 - Of all the coal ash produced in the United States, the waste generated by Appalachian coal operations is the richest in rare earth elements. Researchers from Duke University collected coal ash samples from power plants throughout the United States, including those in the largest coal-producing regions: the Appalachian Mountains; southern and western Illinois; and the Powder River Basin ... more

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