U.S. EPA final report: large-scale mining detrimental in Bristol Bay

The U.S. Environmental Protection Agency today released the final draft of its Bristol Bay Watershed Assessment, which has been under development since February 2011. The study reported that large-scale mining would be detrimental to the salmon, wildlife, and native Alaskan cultures of Bristol Bay. Specifically, depending on the size of the mine, 24 to 94 miles of salmon-supporting streams and up to 5,350 acres of wetlands, ponds and lakes would be destroyed.

The Watershed Assessment, officially known as “An Assessment of Potential Mining Impacts on Salmon Ecosystems of Bristol Bay,” was conducted in response to requests from several tribes and organizations in Bristol Bay. The petitioners had asked EPA to use its authority under the Clean Water Act to restrict development in the Bristol Bay watersheds.

Instead, EPA chose to study available science on the area, compiling its conclusions in an assessment it said would inform future decisions on whether to restrict development. The assessment itself does not restrict development, but Dennis McClerran, EPA’s Region 10 Administrator, said that the agency will use it as the scientific foundation to determine how to respond to the tribes’ 2010 request. “For EPA this is a big, important decision that has a high profile in terms of Alaska and the members of the community there. We will take any decisions we make going forward very seriously.”

Today’s release is the third and final version of the assessment, the result of a three-year process that included EPA visits to Bristol Bay, a scientific review by a panel and more than a million public comments—making it one of the most-commented-on documents ever released by EPA for public review. (Each of the first two drafts received enough comments to make EPA’s ‘top 10.’)

Congressional subcommittees took the EPA to task over the document, inquiring about both the agency’s intent and its methodology.

Pebble Watch provided readers with summaries of the previous drafts, and will also publish a summary of the final version when our staff has completed its review.


EPA Watershed Assessment Timeline – A Pebble Watch graphic


EPA Watershed Assessment

Fact Sheet

Executive Summary

Full document

Pebble Watch Summaries

First Draft

Second Draft

Final version (coming soon)