The fight over the Pebble Mine project near Alaska’s Bristol Bay is back on. Leading the fight against the plans for one of the biggest gold and copper mines in the world is a alliance of local fisherman, conservationists, and the Natural Resources Cefense Council. Here’s what they are fighting to prevent.

The proposed Pebble Mine site would create a two-mile wide open pit mine, thousands of feet deep, directly next to Lake Iliamna, which feeds a 40,000-square mile watershed and Bristol Bay.

As much as 9.1 billion tons of toxic mining discharge would be produced and stored in constructed ponds, covering at least 10 square miles.

Three of the tallest dams in the world would be constructed to hold waste from the mine, including cyanide, sulfuric acid, arsenic, selenium, and other toxic substances.

Here’s what the alliance is seeking to protect.

Both the Kvichak and Nushagak rivers and the salmon industry they support could be affected by the proposed Pebble Mine operations. These two Bay tributaries host the world’s largest sockeye and king salmon runs.

Salmon is one of southwestern Alaska’s most valuable renewable resources, supporting one of only two freshwater harbor seal populations in the world, generating tens of thousands of jobs and over $300 million in revenue each year.

The salmon also support a vast ecosystem, feeding grizzly bears, eagles, wolves, beluga whales, and killer whales.

Bristol Bay is an ecosystem surrounded by tundra, crisscrossed by rivers, and dotted with national and state parks, wildlife refuges and the largest freshwater lake in Alaska.

There are not too many examples in human history of conservation and foresight winning out over short-term greed and destruction, especially when it comes to gold. In this case the stakes are pretty clear; a huge open-pit mine and potentially dams full of toxic waste versus one of the most pristine wildernesses left on the planet and the local economy that depends on the existence of that wilderness. Hope may be on the side of those opposed to the mine, but they better be ready to fight long and hard, because human history and greed are stacked against them.