Hardrock mines across the nation are polluting streams even though federal land managers have been assured they won’t, according to a study released Thursday.
The study, conducted by environmental consultants in Montana and Colorado, looked at water-quality predictions submitted to federal government agencies as part of the mine permit approval process.
In looking at 25 permitted mines, the scientists found that 19 of them ended up exceeding water-quality standards, polluting nearby streams with pollutants such as lead, mercury and arsenic.
“Regulators and mining companies have a responsibility to ensure that sound science and widely available, state-of-the-art methods are used to prevent pollution at mine sites,” said Ann Maest, a Boulder consultant and one of the report’s authors.
Mining industry officials said they were still digesting the report, which they said doesn’t mention that several of the studied mines were abandoned.
“I don’t want to trash the report, but from a layman’s perspective there is some information that’s not reflective of the real world,” said Carol Raulston, a spokeswoman for the National Mining Association.
Raulston added that many of the water-quality predictions submitted in the permit approval process are updated throughout the life of the mine.
Still, environmental groups say the report provides evidence that supports a go-slow approach as permitting agencies consider new mining requests.
New mining claims filed in 2006 for mines on federal public lands are on track to more than quadruple from 2002, said Brian Farnsworth, director of the Information Network for Responsible Mining, a Colorado-based environmental group.
“This report highlights the care Colorado must exercise in considering new mine development, whether it be gold, copper, molybdenum, or uranium mining,” Farnsworth said.
Based on the researchers’ findings, Farnsworth’s group and Earthworks, a Washington, D.C., group that monitors mines, are urging regulators to:
Better screen high-risk mines, particularly those near water resources.
Take a precautionary approach to mine permitting and plan for worst-case scenarios.
Undertake a thorough review of water-quality predictions at all times.
Staff writer Kim McGuire can be reached at 303-954-1240 or kmcguire@denverpost.com.
