New scientific research unveiled today finds that faulty water quality predictions, mitigation measures and regulatory failures result in the approval of mines that create significant water pollution problems. Despite assurances from government regulators and mine proponents that mines would not pollute clean water, researchers found that 76 percent of studied mines exceeded water quality standards, polluting rivers, and groundwater with toxic contaminants, such as lead, mercury, arsenic and cyanide, and exposing taxpayers to huge cleanup liabilities. The research, released by Washington, DC-based conservation group EARTHWORKS and Nunamta Aulukestai (Caretakers of Our Land), has major implications for the proposed Pebble Mine.

The first-of-a-kind reports, "Comparison of Predicted and Actual Water Quality at Hardrock Mines," and "Predicting Water Quality Problems at Hardrock Mines: Methods and Models, Uncertainties, and State-of-the-Art," by Kuipers, P.E., and geochemist Ann Maest, Ph.D., analyzed water quality predictions and outcomes at 25 representative metal mines permitted in the United States during the last 25 years.

The scientists found that predictions of mining's impact on clean water were made without checking the results of past predictions. They also found that predictions were often made using inadequate information, incorrectly applied. Not surprisingly, mitigation measures based on the inaccurate predictions also typically failed to protect clean water.

"The results of this report underscore the unacceptable risks associated with the proposed Pebble Mine," said Bobby Andrew, spokesman for Nunamta Aulukestai. "The Bristol Bay salmon fishery is vital to the communities of this region for subsistence and for the commercial fishing industry and sports anglers. It should not be jeopardized for a Canadian mining company."

Among the report's findings for the 25 mines examined in depth:

76 percent of mines violated groundwater or surface water quality standards

93 percent of mines that are near groundwater and have elevated potential for acid drainage or contaminant leaching exceeded water quality standards

85 percent of mines that are near surface water and have elevated potential for acid drainage or contaminant leaching violated water quality standards

Mitigation measures predicted to protect clean water failed at 64 percent of the mines.

The researchers also found that mines located near surface or groundwater that tapped ore bodies with high potential for acid-generation or contaminant leaching, and near water resources were at high-risk of resulting in water pollution. This finding in particular has serious implications for controversial new mines now being proposed or in permitting, including the proposed Pebble Mine.

"Due to the high risk characteristics of this project and the present inability for mitigation measures to ensure water quality protection, I find the proposed Pebble Project to be highly inadvisable." said Jim Kuipers P.E., co-author of the report.

Sustained increases in metal prices, driven in part by growing demand from China, have triggered a sharp increase in the number of new mines and mine expansions being proposed in the United States. New mining claims filed in 2006 for mines on federal public lands are on track to more than quadruple since 2002.

Based on the researchers' findings, the groups releasing the studies offered the following recommendations:

Better screening of high-risk mines-particularly those near water resources that have the potential to create pollution from acid drainage or metal leaching.

Take a precautionary approach to mine permitting and plan for worst-case scenarios.

Undertake a thorough review of water quality predictions at all existing mines.

Keep the public informed, make risks transparent.

Prevent conflicts-of-interest between mine proponents and expert consultants who prepare predictions and analyses.

The report has been extensively peer-reviewed and presented at five major conferences, including: U.S. EPA's Hardrock 2006 Conference in Tucson, Arizona; Society for Mining, Metallurgy, and Exploration's 2006 Annual Meeting in St. Louis; and the Mine Design, Operations and Closure Conference in Fairmont Hot Springs, Montana, also in 2006.

For copies of the full report and additional background, including a summary white paper and list of peer reviewers and publications, go to: mine-aid.org/predictions