EPA: Mining could affect quality of water, fish

Supporters of the Pebble Mine say it would bring much-needed jobs to rural Alaska, but opponents fear it could destroy a way of life.Supporters of the Pebble Mine say it would bring much-needed jobs to rural Alaska, but opponents fear it could destroy a way of life.(AP) — Failure of a large-scale mine planned near the headwaters of one of the world's premier salmon fisheries in Alaska could wipe out or degrade rivers and streams in the region for decades, the U.S. Environmental Protection Agency said in a draft watershed assessment released Friday.

The report responded to concerns that have been raised about a large copper-and-gold prospect near the headwaters of Bristol Bay. It is a draft, with a final report that could affect permitting decisions due after public comment and peer review.

The Pebble Partnership, the group behind the Pebble Mine project, has called the deposit one of the largest of its kind in the world, with the potential of producing 80.6 billion pounds of copper, 107.4 million ounces of gold and 5.6 billion pounds of molybdenum over decades.

It has been the subject of a heated public relations battle for years. Supporters say it would bring much-needed jobs to economically depressed rural Alaska, but opponents fear it could fundamentally change the landscape and disrupt, if not destroy, a way of life.

The report said that if water from the mine is not managed, contaminants would flow into streams. Even without any failures, the agency 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 due to the water used for mine operations.

It offered no verdict on whether the Pebble Mine project should move forward.

The report is not an in-depth assessment of any specific mine but rather as a look at the impacts of the kind of mining needed to successfully develop the deposit. It is based on a hypothetical mine scenario that the agency says draws in part on plans and studies put forth by the Pebble Partnership.

Therefore, it acknowledges, it may not mirror the location and size of things like a mine pit or tailings storage facility.

The review also could not quantify such things as the consequences of habitat degradation or loss on fish populations due to lack to quantitative information on salmon, char and trout populations.

The assessment put the annual probability of failure for a tailings dam — the kind that could destroy more than 18 miles of salmon stream and degrade the habitat or more streams and rivers for decades — in the range of 1-in-10,000 to 1-in-1 million.

The failures evaluated are those that EPA said have occurred at other large-scale mining projects and could occur during operations or after the mine is closed.

Alaska Attorney General Michael Geraghty had fought EPA over the study, calling the agency's actions are premature and an overreach.

Geraghty raised concerns that the assessment could lead to the agency vetoing mining activity. In a March 9 letter to EPA regional administrator Dennis McLerran, he said that if EPA were to invoke a section of the Clean Water Act that allows it to restrict or bar use of certain waters for dredge or fill materials, that could have the potential to "extinguish" the state's mineral rights and leases held by others.