DES MOINES, Iowa — About two dozen environmental demonstrators are undertaking a 100-mile march in Iowa to protest the Dakota Access oil pipeline. The Des Moines Register reports that they began their eight-day trek Saturday in Des Moines. Advocacy groups Bold Iowa and Indigenous Iowa organized the march to show unity against the $3.8 billion, four-state pipeline. Protesters plan to walk 10-15 miles (16-24 kilometers) a day, completing the march Saturday in Fort Dodge. Native American Coalition of the Quad Cities President Regina Tsosie told the newspaper that the pipeline could break and poison the water. She also says it has desecrated sacred sites. Protesters have pushed back against the pipeline for years. But a U.S. Army Corps of Engineers study of the pipeline released last week says it poses no significant environmental threats.