The Elk River chemical spill occurred on January 9, 2014 when crude 4-Methylcyclohexanemethanol (MCHM) was released from a Freedom Industries facility into the Elk River, a tributary of the Kanawha River, in Charleston in the U.S. state of West Virginia. Crude MCHM is a chemical foam used to wash coal and remove impurities that contribute to pollution during combustion. The "do-not-use" advisory for drinking water from West Virginia American Water's system began to be gradually lifted by West Virginia state officials on January 13 based upon "priority zones."