Native American woman uses a hammer to pound a pipe into the ground Courtesy of Karletta Chief Karletta Chief, an associate professor and Extension specialist in the UArizona Department of Environmental Science, pounds a soil sample tube into the Hogback irrigation canal near Waterflow, New Mexico, on the Navajo Nation in 2017. Soil sampling was done to measure arsenic and lead in the sediment to better understand the impact of the Gold King Mine Spill of 2015 on the Navajo Nation. Chief, who is Diné, will lead the university's new Indigenous Resilience Center.