There could be nearly three times as many abandoned mines on federally owned land than has been charted, mines that pose environmental and physical risks to employees of federal lands agencies as well as users of the land, GAO said.
A report said that some 140,000 abandoned hardrock mines have been identified, of which “about 67,000 pose or may pose physical safety hazards—danger of injury or death—and about 22,500 pose or may pose environmental hazards—risks to human health or wildlife from long-term exposure to harmful substances. Agency officials also estimated there could be more than 390,000 abandoned hardrock mine features on federal land they have not captured in their databases.”
Risks include unsecured entrances, vertical shafts and tunnels, abandoned mills and other structures, potentially lethal gases, and piles of waste containing hazards such as arsenic, lead and mercury.
The Forest Service, BLM, National Park Service, EPA, and Interior’s Office of Surface Mining Reclamation and Enforcement together spent $2.9 billion over the 10 years through 2017 on remediation, nine-tenths of that for environmental hazards, and were reimbursed only about $1 billion of that from former owners and other responsible parties.
“Nearly all” of the officials GAO interviewed said that funding constraints and legal liability issues limited their efforts, while liability issues were the main roadblock to more involvement by conservation groups that otherwise would be interested in helping.