The company exploring whether to reopen the Gilt Edge Mine in the northern Black Hills is backing out of the project.
Last week, Agnico Eagle announced it would terminate its lease agreement with the Environmental Protection Agency and the state of South Dakota.
That lease allowed the company to explore for gold and other minerals in exchange for clean up at the abandoned mine. Gilt Edge is a 1,000-acre superfund site located in the Black Hills.
Kwinn Neff, a local spokesperson for the project with Agnico Eagle, the project was a first-of-its-kind agreement between the government and private industry on a superfund site.
“Unfortunately, after our drilling investigations, of looking at the resource potential, the site conditions, the economics for the project just didn’t meet the threshold for Agnico to move forward into the development stage," Neff said.
Brohm Mining Company abandoned the mine and declared bankruptcy in the early 2000s when the price of gold fell.
Years of surface gold mining exposed sulfuric rock that contaminates the water, turning it into acid mine drainage. That water contains elevated levels of zinc, cadmium, nickel and copper.
Since 2018, Agnico Eagle says it provided $5.25 million in remediation, facility upgrades and water treatment.
The Environmental Protection Agency has managed the site for the last two decades. Both the state and federal governments have spent more than $120 million to treat water and remediate the site. Cleanup costs are around $2 million annually.
EPA officials said they will move forward with planned cleanup actions at the site.
"Including the construction of the cap. We will be working to update the remedial design, bid the project and secure funding for cleanup actions, with construction beginning in 2028," said Richard Mylott, a spokesperson for the US EPA Region 8, in an email. "We expect activity will extend over multiple years due to the size of the project and seasonal limitations related to weather conditions."
