Lake Clark is a spawning destination for a portion of the largest wild sockeye salmon run in the world. Photo: NPCA Photos (Flickr)

Within Alaska’s Bristol Bay watershed lies the world's largest sockeye salmon runs — and one of North America's largest chinook (also known as king) salmon runs — nine major rivers, many ponds, and an abundance of animals. But plans to build a massive Pebble Mine could put the biodiversity of this 40,000 square mile watershed at risk, according to a recent report by National Geographic.

Bristol Bay watershed is also home to the largest deposit of gold in the world and one of the largest of copper. It's also the proposed location for the Pebble Mine. The mine would range up to two miles wide and 1,700 feet deep, with plans for an underground mine of similar scale. The minerals would be extracted by both open-pit mining and a complicated underground method. In addition the mine will require a mill, damlike impoundments, a slurry pipe, and a haul road. The article points out that likely acidic runoff from the mine would be disastrous for fish. "When a sulfur-bearing ore such as the Pebble deposit is exposed to air and water, it produces sulfuric acid, which accelerates the dissolution of copper and other minerals. The resultant metal-laden, acidic cocktail can kill fish and other organisms."

The indigenous Yupik have depended on the flora and fauna in the region for thousands of years. Some area residents worry about the long-term effects the mine will have on the natural environment and those who rely on it. National Geographic reports that "[t]wo elders, believe the threat the Pebble Mine poses to the creeks, rivers, and lakes where salmon spawn also endangers the culture the fish have sustained for centuries.”

But, other residents are singing to a different tune. Lisa Reimers, who heads the Iliamna Development Corporation, is concerned for other reasons. "Outsiders want us to go back to the old ways," she tells National Geographic, adding that "some mine opponents promote a self-serving, sentimental view that ignores what it actually takes to survive."

John Shively, CEO of the Pebble Partnership and once commissioner of the Department of Natural Resources says, "The mine would provide some 2,000 construction jobs and 800 to 1,000 operating jobs." And he hopes to see half of the operating positions go to people living around Bristol Bay. Shively reiterated to National Geographic that "the design of the mine is more environmentally sensitive then ever before."

There is no doubt the Pebble Mine could bring economic fervor to Bristol Bay. But, the gold and copper won't last forever, as the article points out. "The value of this mother lode ranges between $100 billion and $500 billion. But unlike the value of the salmon fishery year in and year out—upwards of $120 million—once these geologic riches are gone, they will never come back."

As plans for the area develop, area residents are faced with one of the toughest and most consequential decisions they will ever be forced to make.