NONDALTON, Alaska - Fly overhead in a bush plane - there are no roads between native villages - and marvel: Eight giant rivers braid across hundreds of miles of wetlands, carving cobalt ribbons through snow-coned mountains before emptying into Bristol Bay.
For more than a century, the wealth of this southwest Alaska watershed has sprung from the astonishing volume of salmon nurtured by those wild rivers. Bank-to-bank, gill-to-gill, tens of millions of silver-hued fish thrash upstream to spawn each year, unrestrained by dams, untainted by pollution.
It is the largest sockeye run in the world, accounting for more than a quarter of wild salmon harvested in the United States, feeding millions at a time when fisheries are dwindling across the globe.
But if fish have made the region's past and present fortune, the future sparkles with the promise of precious metal. Beneath the rolling tundra, straddling the headwaters of two of the watershed's most productive rivers, a Canadian company has discovered North America's biggest deposits of gold and copper, worth about $300 billion in today's soaring commodities markets.
The dilemma is whether Alaskans will have to choose between the two - and whether the watershed, its fish, and a host of other wildlife will be casualties of what could probably be one of the world's biggest mines. The project would entail five earthen dams, of which two would be bigger than China's Three Gorges Dam.
Fueled by daily pro and con advertising on Alaska television, the debate is engaging state and federal politicians, commercial fishermen, Eskimo and Indian villages, the international sportfishing community, environmental groups, major foundations, and multinational conglomerates in a state that rarely turns down a major mine permit.
Opponents say a proposed Pebble mine would destroy one of the planet's last sustainable fisheries, dry up spawning streams, and poison lakes and groundwater with acid runoff. Biologists have found that salmon's genetic radar, which enable the fish to return from the bay to the very streams where they were spawned, can be ruined by microscopic particles of copper dust.
And Bristol Bay's other wildlife - including one of the world's largest brown bear populations, a 45,000-head Mulchatna caribou herd, moose, wolverines, beavers, and eagles - also depend on clean water.
Northern Dynasty officials scoff at what they call an alarmist campaign. "We know Bristol Bay is a sensitive area," said Sean Magee, vice president for public affairs. "But there've been tremendous changes in the mining industry in the past 25 years. These projects can be done safely now: Mining and fishing can coexist."
What is clear is that the mine - wedged between Lake Clark and Katmai national parks - would entail a staggering scale of industrialization.
If the full resource were developed, as much as 12 billion tons of earth would be excavated and milled to extract the tiny flecks of metal: about 82 million ounces of gold, 67 billion pounds of copper, and 4 billion pounds of molybdenum.
Ten square miles of impoundments would fill two valleys, to store in perpetuity more than 2.5 billion tons of waste rock and toxic residue.
And to transport equipment and ore, a new 104-mile road would cut through undeveloped forest and wetlands, skirting Lake Iliamna, Alaska's largest body of fresh water. The lake is host to rare freshwater seals and is a primary spawning bed for sockeye, the red-fleshed salmon that are among the world's most prized eating fish. Pebble may be just the beginning.
Northern Dynasty's exploration has sparked a surge of claim-staking, with eight other companies asserting rights over more than 700 square miles nearby. This month, the US Bureau of Land Management will make a final decision on whether to allow hard-rock drilling on 3,300 square miles of federal land in the area.
"A massive mining district would carve the heart out of the watershed," said Richard Jameson, president of the Renewable Resources Coalition, a statewide anti-Pebble group, which is backing legislation and ballot measures to stop the mine.
Northern Dynasty's environmental studies won't be ready until 2009 and obtaining the 67 required state and federal permits could take three more years. But already, said Magee, "Debate is at fever pitch."
Opponents are waging an uphill struggle. Because Pebble is on state land, the key decisions will come from the Alaska Department of Natural Resources whose commissioner, Tom Irwin, is a former mining executive and whose mission is to promote development.
"It's the fox guarding the chicken coop," said Norman Van Vactor, Bristol Bay manager for Peter Pan Seafoods, which operates the area's oldest cannery.
The outcome may hinge less on environmental values than on which economic resource Alaskans value most.
"You can't eat gold," says Robin Samuelsen, a commercial fisherman and chief of the Curyung Tribal Council in Dillingham, the region's principal town.
Bristol Bay's fishery, with $450 million in annual economic benefits, employs 10,000 people in seasonal jobs, including 6,800 fishermen. And it could grow in value: Because contaminants in farmed seafood have come to light, consumers are increasingly turning to wild salmon for health benefits and its superior taste.
"I'd rather eat porcupine than hamburger," says Jack Hobson, tribal council president of Nondalton, the village closest to the proposed mine. An Athabaskan outpost of about 220 residents, with its homes of weathered clapboard and corrugated steel scattered along a dirt road, is plastered with anti-Pebble signs.