Rivers and streams in the world's premier wild salmon fishery would be greatly degraded for decades should a vast gold and copper mine be built and then see a failure in the dam holding back its mine waste, the U.S. Environmental Protection Agency said in a draft report Friday.
The proposed Pebble Mine in Alaska has stirred passions for and against, with fishermen and native tribes in the Bristol Bay watershed generally against the project.
If the tailings dam were to break, the draft report stated, some 20 miles "of salmonid streams would be destroyed and more streams and rivers would have greatly degraded habitat for decades."
Other, smaller failures could put contaminants into the streams if water from the mine is not properly managed. In addition, the native cultures that rely on salmon for food could see a significant change in their lifestyles, the report said.
Even without any failures, the EPA said, there would still be an impact on fish, including eliminated or blocked streams, removal of wetlands and a reduction in the amount and quality of fish habitat because of water use by mine operations.
The annual probability of failure for a tailings dam was estimated in the range of 1-in-10,000 to 1-in-1 million.
Project backers note that the deposit is one of the largest of its kind in the world and could produce 80.6 billion pounds of copper, 107.4 million ounces of gold and 5.6 billion pounds of molybdenum, used in steel-making, over decades.
The EPA, which said it would solicit public opinion through July 24 before issuing a final report, summarized the significance of the area this way:
The Bristol Bay watershed in southwestern Alaska supports the largest sockeye salmon fishery in the world, is home to 25 Federally Recognized Tribal Governments, and contains large mineral resources.The potential for large-scale mining activities in the watershed has raised concerns about the impact of mining on the sustainability of Bristol Bay’s world-class fisheries, and the future of Alaska Native tribes in the watershed who have maintained a salmon-based culture and subsistence-based lifestyle for at least 4,000 years..
Alaska Attorney General Michael Geraghty has called the EPA's involvement premature and an overreach, The Associated Press reported.
In a March 9 letter to the EPA, he said that if it were to use the Clean Water Act to block the Pebble mine, that could have the potential to "extinguish" the state's mineral rights and leases held by others. In that case, he warned, Alaska would explore "all available legal options."
Sen. Lisa Murkowski, R-Alaska, said Friday that while she was "pleased this draft assessment does not contain a preemptive veto" she worried that could still happen before a permit is even sought for the project.
"I have consistently been clear about two things concerning the Pebble project: I will not trade fish for gold, but I oppose a preemptive veto prior to proper evaluation of an application and actual project description," she said in a statement.
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