A U.S. Environmental Protection Agency report says build-out of the large-scale Pebble mine near the headwaters of a world-class salmon fishery could wipe out as many as 90 miles of streams and alter stream flows.
It said mining activity would claim at least 24 miles of streams in the Bristol Bay region, based on the scenarios evaluated, with the loss of wetlands ranging from 1,200 to 4,800 acres.
EPA regional administrator Dennis McLerran said the revised report generally affirms conclusions reached in the initial report last year.
The revised assessment will undergo a new round of peer review and public comment before EPA releases a final report that could affect permitting decisions.
The group behind the proposed Pebble Mine project in Alaska is dismissing the report as unnecessary, flawed and consistent with demands from opponents of the project.