The Interior Department finalized plans Thursday to permit drilling, mining and grazing in areas of southern Utah that had once been protected as two national monuments, sparking an outcry from tribal groups and conservationists.

The decision comes more than two years after Trump dramatically cut the size of the monuments, Bears Ears and Grand Staircase-Escalante, and is likely to intensify a legal fight over the contested sites.

The expanses of wind-swept badlands, narrow slot canyons and towering rock formations are sacred to several Native American nations and prized by scientists and outdoor enthusiasts. Bears Ears contains tens of thousands of cultural artifacts and rare rock art. In the rock layers of Grand Staircase, researchers have unearthed 75 million-year-old dinosaur fossils.

But the lands also harbor significant amounts of oil, gas and coal that the administration hopes to develop, as well as grazing land valued by local ranchers. The earliest the government could approve new mining claims and other kinds of development is Oct. 1, because of language Congress adopted in a spending bill.

Officials from the Interior Department and U.S. Forest Service who manage the lands have said the new plans balance the region’s economic interests against the need to safeguard natural and cultural wonders. Casey Hammond, the Interior Department’s acting assistant secretary for land and minerals management, noted that the areas excluded from monuments are still protected by federal environmental laws.

“We are advancing our goal to restore trust and be a good neighbor,” Hammond said Thursday.

Under the plan, much of Bears Ears and nearly 1 million acres in and around Grand Staircase are open to grazing. BLM will also make two new routes in Grand Staircase open to off-road vehicles, which archaeologists and conservationists are concerned could damage vulnerable artifacts and natural features.

The plans don’t allow for commercial logging, according to Kimberly Finch, communications director for Bureau of Land Management Utah. But trees and other vegetation can be cut as part of sometimes controversial “treatments.”

BLM has received 15 mining claims on lands excluded from the two national monuments since their boundaries were redrawn, Finch said. The new management plan allows for even more mining and drilling, though Finch said that the bureau hasn’t gotten many requests for mineral development on those lands.

The decision to overhaul what activities are permitted on large swaths of federal land in southern Utah comes as the Bureau of Land Management is eyeing much bigger changes to how it manages 245 million acres of public land across the country and the minerals buried underneath them.

In a letter obtained last month by The Washington Post, the top BLM official in Alaska informed tribes that the agency is considering making it easier to log and extract energy from lands it oversees. The changes would streamline environmental reviews, Chad Padgett wrote, to save taxpayer money and be more responsive to local needs.

The 1906 Antiquities Act empowers a president to protect public lands of archaeological significance. President Bill Clinton first designated Grand Staircase-Escalante a national monument in 1996. President Barack Obama designated Bears Ears a national monument 20 years later.

President Trump’s Interior Department redrew those boundaries so that Grand Staircase is half its former size and Bears Ears has shrunk by 85 percent.

A coalition of groups sued the administration immediately after those new boundaries were announced, arguing that the act does not give a president the authority to revoke the national monument designations of their predecessors.

The Justice Department last year sought to have the two lawsuits dismissed, but a federal judge denied the motions.

Several plaintiffs roundly criticized the administration for moving forward with management plans while the cases were still in court. But Hammond said Thursday that the Interior Department would not delay its decision to match a slow-moving legal process.

“If we stopped and waited for every piece of litigation to be resolved, we would never be able to do much of anything around here,” he said.

In developing the plan for Bears Ears and Grand Staircase, Hammond said, the BLM consulted with Native American tribes and considered thousands of public comments.

But representatives from Utah Dine Bikeyah, a non-profit that led tribal efforts to secure protection for Bears Ears and is a lead plaintiff on the monuments lawsuits, called BLM’s outreach to tribes “insufficient.”

“Bears Ears is alive with active ceremonies and prayers ... that ensure our survival and spiritual connection to this place,” said the group’s communications director Alastair Bitsoi. “The decision by President Trump to take away 85 percent of the monument really reflects lack of respect and lack of ... interest in how Native people use this landscape.”

“The Trump administration ... built their plans on an unlawful foundation,” said Heidi McIntosh, managing attorney of the Rocky Mountain office of the environmental advocacy group Earthjustice. Her group is also party to the monuments lawsuit.

“This headlong spree to open up monument lands to extractive industries and development is illegitimate, and could only be done by turning a blind eye to the law and flat out ignoring the Native American tribes for whom Bears Ears is sacred," McIntosh said.

But ranchers, including the National Cattlemen’s Beef Association’s Kaitlynn Glover, called the decision “welcome news for local communities and rural economies."

Glover, the association’s executive director for natural resources, said the 1906 Antiquities Act "has been abused to lock up millions of acres” that could be grazed and used for other activities.

The changes to the monuments have also won praise from officials in Utah, including Sens. Mitt Romney (R) and Mike Lee (R) and Gov. Gary R. Herbert (R).

Romney called Thursday’s announcement “a welcome step,” while Herbert said in a statement: “Monuments should be as small as possible to protect artifacts and cultural resources. And they should not be created over the objections of local communities.”

Tribes and environmental groups argue the plans will make way for destruction of sensitive cultural areas and vital natural landscapes. They worry Thursday’s decision to open public access to the lands will allow for increased road development and off-road-vehicle use that will affect artifacts and ecosystems, while grazing and logging will alter the habitats of many important species.

Conservationists are particularly concerned about chaining, a process in which bulldozers drag long chains across terrain to uproot plants and trees.

“These plans represents the lowest common denominator for BLM stewardship,” Stephen Bloch, legal director for the Southern Utah Wilderness Alliance, one of the plaintiffs in the monuments lawsuits, said in a statement. “One of the wildest landscapes in the lower forty-eight states will be lost if these plans are carried into action over the next few years."