As commercial fishermen in Bristol Bay were busy landing salmon, the Trump administration on Tuesday moved to cancel the Environmental Protection Agency's 2014 action that would have blocked development at the Pebble gold and copper prospect in Southwest Alaska.

The EPA's proposal to cancel its earlier, proposed determination highlights the agency's new approach since the victory of President Donald Trump in November, and the appointment of its new, pro-industry administrator, Scott Pruitt.

It also comes on the heels of a settlement agreement in May between the agency and the developers of the prospect, Pebble Partnership.

Under President Barack Obama, the EPA in 2014 issued its proposed restrictions under the Clean Water Act, arguing that the mining plan at the gold and copper prospect would threaten the valuable Bristol Bay salmon fishery.

Pebble sued, saying the effort pre-emptively thwarted the project before the company could undergo the standard regulatory process and submit plans for agency approval. In 2014, U.S. District Judge Russel Holland stopped the EPA from taking action that could halt development at the prospect, leading to the settlement.

For the next 90 days, the EPA will seek public comment on withdrawing the proposed restrictions.

Tuesday's announcement is "a stab in the back" to subsistence and commercial fishermen in Bristol Bay, said Alannah Hurley, executive director of mine opponent United Tribes of Bristol Bay.

The proposal came as fishermen enjoy one of their biggest salmon-fishing seasons in years, said Hurley, reached by cellphone as she was commercial fishing with a net off the beach near Dillingham.

"Doing it in the heart of the fishing season just adds insult to injury," she said.

The opposition to the mine, including lodge owners led by Trout Unlimited, appears to be just as active as before.

Hurley said residents in Bristol Bay are overwhelmingly opposed to the project, and, as in comments made before the original EPA proposed determination, will come out in droves again to fight the project, she said.

"We won't take this lying down," she said.

The timing of the public comment period was guided by the May 11 settlement, not the Bristol Bay fishing season. The settlement called for the comment period to begin by Tuesday, 60 days after the settlement, said Suzanne Skadowski, an EPA spokeswoman.

The 90-day comment period is longer than the typical 30-day comment period, allowing extra time for fishermen to voice opinions once fishing seasons end, she said.

Sen. Lisa Murkowski, R-Alaska, in late June had raised concerns with Pruitt, asking for enough time so local residents could weigh in.

Pebble, owned by Northern Dynasty Minerals of Canada, said Tuesday it has responded to concerns about the project, including pursuing a smaller mine plan with details to be released later this year.

Opponents have said the smaller plan is a ruse to get the development underway, and that the project near some of the bay's headwaters would soon be expanded to the original large footprint.

"We have long advocated that the normal, fair and objective permitting process is the appropriate place to make decisions about this important project," said Pebble in a statement emailed by Mike Heatwole, a spokesman with the project.