BRISTOL BAY, Alaska — Alaska voters are considering a ballot measure that would make the state's already strong protections for salmon fisheries even stronger, and make new mining and oil exploration projects difficult — if not impossible.

The measure, called Proposition 1, is intended to protect Alaska’s salmon runs, especially in Bristol Bay, the designated site of the massive proposed open-pit mine project, the Pebble Mine. The site contains some of the largest undeveloped copper and gold deposits in the world.

As things stand, the state has to prove that any big project would not impact healthy salmon waterways. If Prop 1 passes, the roles reverse, and the project would have to prove the habitat is not home to salmon at all, a drastic change to current regulation.

"Salmon streams don't recover. That's the point of this ballot measure," said Morgan Jones, a third-generation fisherman supporting Prop 1 and opposing the Pebble Mine. "Once you dig up a salmon nest, it's gone. It's not like you can re-lay a place where salmon can spawn."

But the mining industry argues the measure goes too far and would force all mines to endure lengthy regulatory delays. "You look at some of the projects on the horizon for us, and it would just be a deal killer," said Kara Moriarty, president and CEO of the Alaska Oil and Gas Association. She argues that the measure could have far-reaching consequences for Alaska, as the oil and gas industry produces nearly $2 billion a year in tax revenue alone.

Alaska also has the highest unemployment rate in the country. Prop 1 pits the state’s powerful mining and oil industry against the commercial fishing, which creates significantly more direct jobs than the extractive industries, and catches the majority of America's seafood.

But the pro-salmon campaign is being outspent 9 to 1, and mining proponents say they have good reason to spend more than $11 million on opposing Prop 1: They argue that the costs of the measure are impossible to predict, but it could effectively end mining and oil exploration in the state.

This segment originally aired October 2, 2018 on VICE News Tonight on HBO.