THE TOWN OF DILLINGHAM, which sits on the northeastern edge of Bristol Bay near the mouth of the Nushagak River, consists of a weathered collection of buildings radiating out from the huge Peter Pan Seafoods salmon-cannery complex. Bristol Bay's first cannery opened nearby in 1884, and salmon remains at the core of the town's identity and economy, which helps explain why it's become a solidly anti-Pebble place. By the time I arrived on June 21, Dillingham's population had doubled from the 2,500 of winter. The two-month salmon season is a harsh, sleep-deprived ordeal, but the fishermen return, year after year, like the fish they chase.

The battle over this pristine piece of wilderness has been fierce, pitting two of Alaska's long-established extractive industries against each other: mining and fishing. Mining is a substantial force in Alaska's economy—it supports 5,500 jobs and was worth $3 billion in 2008. Pebble promises up to 1,000 new jobs for an economically impoverished area, along with improved infrastructure and cheaper power. But the salmon run has been an integral part of the culture and subsistence lifestyle of the natives for millennia and is no small economic force itself: Bristol Bay's commercial fishery has been around for more than 120 years, employs about 10,000 people, and generates more than $300 million annually. Sportfishing attracts anglers from all over the world and is worth another $100 million a year.

The Pebble Partnership—the corporation formed by Canada's Northern Dynasty and the UK-based Anglo American—owns the mineral rights, giving it the authority to conduct the exploratory drilling and other tests needed to apply for mining permits. The Alaska Department of Natural Resources coordinates the permitting process, but the mine will require some 60 state and federal permits before development can proceed, and even then, the legislature or the governor could intervene. The companies plan to submit their permit materials in 2010, initiating a process that would take at least two years. If approved, Pebble would then enter a construction phase that could last from 2013 to 2015, with the mine possibly opening, at the earliest, in 2016, for what could be a 50-to-80-year life span.

Over the past year, the Pebble issue had been much on Alaskans' minds as both sides bought TV, radio, and print ads in an effort to get their message out before an August 2008 vote on the "clean-water initiative," a ballot measure that would have effectively shut down development at Pebble by enacting stricter water-use standards for mines. Alaskans Against the Mining Shutdown, as one group dubbed itself, portrayed environmentalists as statewide mine killers, while the bill's supporters labeled the Pebble Partnership as greedy outsiders who would exploit Alaska and leave behind nothing but a mess. Governor Sarah Palin—whose daughter Bristol is named for the bay where she and her husband have fished—got involved, voicing her opposition to the ballot measure just before she was nominated for vice president. The initiative failed, with 57 percent voting no.

Palin's involvement raised the issue's profile outside of Alaska, and Bloom has been making some noise herself. She first became serious about it in 2006, while researching a master's thesis on Bristol Bay salmon at the SIT Graduate Institute, in Vermont. Now, in her off-season job as the commercial-fisheries outreach director for Trout Unlimited Alaska, Bloom serves as the liaison between commercial and sportfishermen. Through her work with Nunamta Aulukestai and other native groups, she has developed strong ties to indigenous communities. She's been quoted in The Boston Globe and Gourmet and promoted a deal with Wal-Mart for the chain to market Bristol Bay salmon. An acclaimed documentary about Pebble, Red Gold, has been making the rounds at film festivals; Bloom was one of the chief facilitators for the filmmakers when they visited in the summer of 2007. Her most recent coup: helping to recruit Sig Hansen and his crew from Discovery's Deadliest Catch to the anti-Pebble cause.

Bloom was supposed to join me in Dillingham on June 21 to attend the Pacific Fisheries Legislative Task Force meeting—an annual gathering of state legislators from Alaska and the Pacific Northwest—but low tide had rendered the harbor inaccessible, keeping her away. The meeting, a forum for airing fishing issues, this time became a de facto hearing on Pebble, with the main event being a talk by John Shively, the CEO of the Pebble Partnership. In advance of Shively's presentation, nearly a hundred gruff-looking commercial fishermen—one wearing a sweatshirt stenciled with the words Puck Febble—had assembled in the parking lot for an impromptu protest lunch of grilled salmon.

"I do have a feeling that maybe this is a little bit how General Custer felt," Shively joked when it was his turn to talk. "I know most of you in this room wish I would just go away." A former commissioner of the Alaska Department of Natural Resources, Shively, in khakis and a button-down shirt, was perhaps the lone pro-Pebble voice among the 75 or so people in the room. "We are not guaranteed a mine," he said, "but we do have a right to pre­sent that proposal to the government."

From 2002 to 2008, the Pebble Partnership spent $360 million on exploration and studies required by the permitting process, including $132 million on environmental and socio­economic assessments alone. With more than 800 exploratory holes, some going down thousands of feet, drilled on the claim so far, the partners have concluded that they're sitting on some 72 billion pounds of copper, 4.8 billion pounds of molybdenum, and 94 million ounces of gold. Extracting that ore could mean churning up as much as 7.5 billion tons of earth. Initial plans called for two mines side by side, a below-ground operation on the eastern side of the claim and, to the west, a massive open-pit mine that could be one of the largest in the world.

"Obviously, its location is a hugely sensitive place," Shively said. "It requires us to persuade people that we can take care to protect the fish and the water."

To help convince them, Pebble has gone beyond what's required to minimize the impacts of exploration—traveling by helicopter instead of bulldozing roads, for example, and setting their drill rigs on tundra-protecting wooden platforms. Through a combination of technology and attention to detail, says Pebble's vice president of pubic affairs, Mike Heatwole, the company believes it can engineer a safe mine with a relatively small footprint that will protect the ecosystem from any ill effects. Just how they will do that, he isn't saying, explaining that they still need to collect and analyze the data before deciding what plans will look like.

Opponents are skeptical. Infrastructure is one problem: The mine will require 85 miles of road in a roadless wilderness area; a concurrent length of pipeline to transport the ore slurry; a new deepwater port on Cook Inlet for ships to receive it; and some way—most likely a new natural-gas power plant—of generating a small city's worth of electricity. It would draw millions of gallons of water out of nearby streams and rivers—which in itself could destroy fish habitat. And it would require enormous earthen dams to hold back tailings ponds: billions of tons of wastewater, rock, and unrecovered minerals, including potentially toxic sulfides that could oxidize to create sulfuric acid, which in turn might leach metals out of rock and into the groundwater, posing the most immediate threat to the salmon. Pebble says they'll prevent acidification by keeping the waste underwater, away from air; critics point out that, because of the area's highly permeable geology, there is simply too much groundwater moving around to contain the pollutants.

Anti-Pebble groups like the Renewable Resources Coalition cite cautionary tales like the Summitville Gold Mine, in Colorado, which was permitted as a "zero-discharge" mine but sterilized 17 miles of the Alamosa River in the mid-eighties, and Utah's Bingham Canyon mine site, which, while far older, features geology similar to Pebble's and has contaminated more than 70 square miles of groundwater. Heatwole rejects these comparisons to older, dirtier mines, insisting that the company is well aware of the environmental risks. But history is against them: A 2006 study of 25 large-scale U.S. mines by the watchdog group Earthworks found that 19 of them failed to comply with the water-quality standards required by their permits.

"The environmental record of hard-rock mining is pathetic," says Daniel Schindler, professor of aquatic fishery and sciences at the University of Washington. "And I'm probably being generous in calling it pathetic."

Rick Halford, a former Alaska state senator who's generally pro-extraction but opposes the Pebble mine, summed it up at the Dillingham meeting. "Mining is an important part of Alaska's heritage," he said. "But this particular prospect, in this particular location, is a disaster for all time."