RIGOROUS scientific study by the federal Environmental Protection Agency has effectively turned thumbs down on a massive gold, copper and molybdenum mine proposed for a pristine Alaskan salmon fishery.

A statement by Seattle-based EPA regional administrator Dennis McLerran sums up the findings and conclusion: “Bristol Bay’s exceptional fisheries deserve exceptional protection.”

Washington lawmakers in Congress led efforts for close review of the mining proposal. U.S. Sen. Maria Cantwell, D-Wash., was an early voice for using the federal Clean Water Act to block the project.

In the meantime, the proposal by Northern Dynasty Minerals of Vancouver, B.C., has been losing investors, including Rio Tinto and London-based Anglo American.

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The Pebble Mine would produce a nearly mile-deep, open mine pit that would generate epic levels of excavation materials that would have to be secured for generations.

In the process, miles of streams would be lost, along with wetlands, lakes and ponds. Environmental havoc would be triggered by even the smallest scale operation proposed.

Earlier, another long shadow was cast by a 2013 report by the University of Alaska Institute of Social and Economic Research.

The report found economic activity totaling $1.5 billion from the Bristol Bay fishery. Those salmon provide fishing and processing employment worth $674 million in Washington, Oregon and California. This vast Alaskan resource provides 12,000 seasonal jobs and 6,000 full-time jobs in the three states.

The Pebble Mine proposal represents environmental and economic disasters waiting to happen.

The EPA has opened its report for public comment, and the possibility for revised mining proposals within the defined limits.

EPA must proceed with the end in mind: protection of a pristine, natural treasure.

Editorial board members are editorial page editor Kate Riley, Frank A. Blethen, Ryan Blethen, Sharon Pian Chan, Lance Dickie, Jonathan Martin, Erik Smith, Thanh Tan, William K. Blethen (emeritus) and Robert C. Blethen (emeritus).