At a community meeting held by the U.S. Environmental Protection Agency (EPA) and the University of Arizona Superfund Research Program (UA SRP), residents of Dewey-Humboldt, Ariz., learned about remediation efforts for the area's Iron King Mine and Humboldt Smelter Superfund Site.
The Iron King Mine and Humboldt Smelter area adjacent to the Dewey-Humboldt community was declared a Superfund site in 2008.
EPA Remedial Project Manager Jeff Dhont presented an overview of the area's historical mining and smelter activities that created large amounts of uncontrolled mine waste, called tailings, with elevated levels of several metals, including arsenic. Older mine tailings are prone to wind dispersion and water erosion, potentially elevating heavy metal concentrations in the soil in neighboring communities.
"We can't make it all go away, but looking at the health impacts, we need to select a remedial action to clean up the site," Dhont said, referring to the contaminants. He further explained that the investigative team must determine the health and exposure risks of the site’s contamination and pick a remediation option with the public's input. The team is still in the remedial investigation stage, he said.
UA SRP researchers are working in the Dewey-Humboldt community and nearby Superfund site to assess whether wind-borne dust in the area carries metals, the Dewey-Humboldt residents exposures to metals, and whether certain plants can stabilize metal contaminants in mine tailings. They have also collaborated with residents to determine levels of metals in homegrown vegetables and provided additional information about environmental health issues in the region.