A debate is brewing in Alaska over what's worth more – the gold in the ground, or the gold in the water. A record 60 million salmon surged through the state's Bristol Bay last month. Some 30 million were caught and will feed half of the world's demand.

Near the headwaters of the bay, the mining company Northern Dynasty says it has found what could become the biggest gold and copper mine in the world. But if they dig it, critics warn the side effects could be toxic, reports Bill Weir.

The mine's development stalled under President Obama, but President Trump's administration has given the controversial project new life.

As part of the CNN series "The Wonder List," Bill Weir learned how many forms of salmon-loving life might be affected – including the big, furry residents of Katmai National Park.

"Here's that one place where bears respect people, because the people respect bears," said naturalist Brad Josephs.

"The Wonder List" CNN

There was a time when the state of Alaska thought that if they killed the bears, there would be more fish for the people, but Josephs said the salmon runs weren't nearly as healthy. Bears play an important role in the ecosystem. When a bear poops in the woods, he's spreading marine nutrients into the valley. They are stewards of an environment where everything is connected by salmon.

"I'm scared every year, are they gonna come back?" Josephs said.

"Every year so far, they show up like miracles, and I say, 'Oh, thank you!' Everybody's happy and the bears are happy. And the gulls and the eagles and the foxes and the wolves. They all cash in," Josephs said.

At the top of that food chain are all the people who literally cash in on the salmon. What worries some of them these days is what lies beneath the ground above Bristol Bay, where there lies a monster fortune.

"The Wonder List" CNN

Northern Dynasty believes there are a hundred million ounces of gold in those hills and 80 billion pounds of copper. The little chunk of real estate could be worth a half a trillion dollars over the next century or so.

In addition to gold and copper, that ground holds millions of tons of sulphur. Mixed with air and water, sulphur turns to acid.

Critics of the Pebble Mine worry that acid could get into the watershed, destroying one of the last great salmon runs left on the planet.



The developers of Pebble Mine insist that they can pull the gold and copper out safely, but fishermen, conservationists, biologists and most native tribes disagree. They fought this project for more than a decade, but then President Trump won. One of EPA administrator Scott Pruitt's first acts is opening the door, settling lawsuits and allowing the development of the mine to move forward.