By Timothy Puko 

WASHINGTON -- The Army Corps of Engineers is rejecting the environmental plan for the massive Pebble Mine in Alaska, likely marking an end to one of the country's most controversial proposals to extract gold and copper in a pristine wilderness.

The project would violate Clean Water Act guidelines, the corps said.

The Pebble Mine called for excavating an open pit to mine hundreds of billions of dollars worth of minerals from under the Bristol Bay watershed in Alaska's southwest. It has drawn widespread opposition from locals and environmentalists, including some conservatives, for the risk it poses to some of the world's largest wild salmon populations.

The project would violate rules for disposing of "fill material," according to a statement from Alaska District Commander Col. Damon Delarosa of the Army Corps of Engineers. The statement didn't give further details.

The corps "concluded that the proposed project is contrary to the public interest," the statement added.

For now, the decision likely ends a decadeslong quest to reach one of the largest known and untapped sources of gold and copper in the world.

President-elect Joe Biden said this summer he would stop its development, and company leaders have previously said they need federal permits to bring in well-heeled partners that could invest to help them continue.

The project's owners, a subsidiary of Canada's Northern Dynasty Minerals Ltd., had once valued the ore at $300 billion to $500 billion and drew partnerships with some of the world's largest mining companies, including Anglo American PLC and Rio Tinto PLC. But those companies pulled out amid falling commodity prices and growing pressure over environmental concerns.

A 2014 report from the Environmental Protection Agency said the Pebble mine could have significant adverse effects on the region's fisheries and the Native Alaskan communities that depend on them. Fifteen federally recognized tribes in the region had formed a coalition to stop it, and a poll they helped commission in June of this year showed likely voters statewide opposed the project by a 2-1 margin.

The decision comes months after some of President Trump's most prominent supporters -- including his eldest son, Donald Trump Jr. -- mounted a last-minute push against the project. They wanted the president to intervene against a project his administration had previously supported.

The Corps in July published a final environmental assessment saying the project posed no serious risk. Then a month later, amid widening opposition, the Corps made demands for severe mitigation measures to receive final approval.

John Shively, chief executive of Pebble Limited Partnership, the project's developer, called Wednesday's decision "politically driven" and said it would be a loss for the local economy and for clean-energy businesses that need cheap copper to keep growing.

"We are obviously dismayed by today's news," he said in a statement. July's environmental assessment "clearly stated it could be developed responsibly. It is very disconcerting to see political influence in this process at the 11th hour."

A White House spokesman didn't immediately respond to a request for comment.

The company plans to appeal the decision, the statement said without giving further details. Its leaders have work to do "sorting out their next steps," it said.

Environmentalists said they now plan to pursue long-term environmental protections for the region. While the incoming administration is opposed to the project, the deposits are still there and the current developers or new, better-financed developers could seek to revive it later.

"Today's decision gives the people of Bristol Bay temporary relief from this mine," said Guido Rahr, leader of the Wild Salmon Center, which has helped marshal opposition from influential Republicans and sportsmen's groups this summer. "It's now time for EPA to use the Clean Water Act to kill this mine once and for all."

Write to Timothy Puko at tim.puko@wsj.com

 

(END) Dow Jones Newswires

November 25, 2020 14:38 ET (19:38 GMT)

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