The cool, shallow waters of Bristol Bay are surrounded by a verdant cushion of tundra, crisscrossed by swift rivers and dotted with lakes large and small. Grizzlies, wolves, seals and whales roam this nearly untouched ecosystem, all drawn by the same lure: tens of millions of thrashing salmon, charging upstream to spawn. Huge salmon runs are the linchpin of this glorious wilderness, supporting valuable commercial fisheries, indigenous people and a vast array of wildlife. Yet the whole system could come crashing down if giant mining interests get their way.

Foreign mining companies, including Mitsubishi, Rio Tinto and Anglo American, are eyeing low-grade gold and copper deposits on pristine land in the Bristol Bay watershed in an area known as Pebble. A Bush-era management plan could open up more than 1 million acres of public land in the region to mining. The only way to extract this ore is through destructive and pollution-producing hard-rock mining.

A study of mines similar to the proposed Pebble mine showed that 85 percent of them polluted nearby waters. At Pebble, a proposed open-pit mine would be 2 miles wide (enough to line up nine of the world's longest cruise ships end-to-end) and 2,000 feet deep (enough to engulf the Empire State Building). As proposed, the mine would generate more than 9 billion tons of waste held behind a series of massive earthen dams -- all of them taller than China's Three Gorges Dam and located just 20 miles from an active fault line.

A single accident here would be disastrous. But even the construction and operation of the mine could disrupt salmon migration and jeopardize the larger ecosystem. It’s a risk most local Alaskans are not willing to take -- the true gold of this region, they say, is its fish and wildlife.