As ominous as it might seem, the Trump administration's plan to reverse limits on new mining, drilling and development across a vast swath of federal land in southern Utah is unlikely to unleash a fossil fuel bonanza anytime soon.

These days, it's too costly for fossil fuel companies to extract the oil, gas and coal buried within 2 million redrock acres Trump excised two years ago from the Grand Staircase-Escalante and Bears Ears national monuments.

That's not to say that there aren't climate impacts of the Trump administration's final decision, announced Thursday, to strip national monument protections from the wild, desolate landscape, which archeologists and conservationists treasure for its artifacts and natural rock formations. The land also has rich spiritual connotations for the indigenous people of the Four Corners region.

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In a report ordered by the Obama administration but published just over a year ago, the U.S. Geological Survey estimated the carbon dioxide emitted and retained by public lands in the United States: Nearly 24 percent of U.S. carbon dioxide emissions can be traced to public lands, the report found, and those same lands act as a sink that sucks up and stores carbon from the atmosphere, offsetting in addition about 15 percent of the nation's CO2 emissions.

The climate impact of the final Trump policy is more likely to affect these carbon sinks than it is emissions. The new management plans allow vegetation to be removed on the land excluded from the monuments for better livestock grazing, said Steve Bloch, an attorney for the Southern Utah Wilderness Alliance, one of several tribal, business, scientific and advocacy groups suing over the monuments' downsizing.

He said the management plans would allow large areas of native vegetation to be destroyed, fragile cryptobiotic soils to be trampled and mature pinion, Juniper and sagebrush to be removed—diminishing the land's value for combating climate change.

The stage is set for the federal Bureau of Land Management, he said, "to rush ahead, hand-in-hand with the state of Utah, with activities that are designed to improve range for cattle at the expense of disturbing these intact natural ecosystems."

Casey Hammond, acting assistant secretary for land and minerals management at the Department of Interior, told reporters Thursday that no federal land was being sold off, and that numerous laws remain in effect to protect the cultural and natural value of the 2 million acres of land carved off from the monuments.

"The decisions mark an important moment in Utah's history by providing certainty to local communities, business owners, permittees and the recreating public on what activities are appropriate for those public lands," Hammond said. "With these decisions, we are advancing our goal to restore trust and be a good neighbor."

Utah Gov. Gary Herbert, local officials and GOP members of Utah's congressional delegation praised the Trump administration's new approach to managing the former monument lands for more economic opportunities.

But coal in and around the Grand Staircase—about 60 percent of Utah's total reserves—is likely to stay in the ground because the cost of mining on the wild and remote Kaiparowits Plateau and the expense of transporting it to market was uneconomical—even before coal demand plummeted.

That's also why there's been so little interest from oil and gas companies in developing leases on the 1.1 million acres the Trump administration carved from the original Bears Ears boundaries.

Adding to the uncertainty surrounding oil and gas development, lawsuits were filed immediately after Trump reduced the size of the Grand Staircase-Escalante and Bears Ears national monuments. When Trump signed two proclamations at the Utah State Capitol on Dec. 4, 2017, the move represented the most sweeping reduction in protections for public land in U.S. history.

President Barack Obama had created the Bears Ears Monument a year earlier. President Bill Clinton Grand Staircase-Escalante as a national monument in 1996 as a kind of research park for paleontology.

The legal challenge, now consolidated in two lawsuits before a federal judge in Washington, was originally brought by more than two dozen plaintiffs, including Native American and environmental groups, scientific and archeological organizations and a group of business and philanthropic backers called Grand Staircase Escalante Partners.

U.S. District Judge Tanya S. Chutkan denied the Trump administration's request to dismiss the cases last fall. She is now considering the question of whether it was illegal for Trump, under the 1906 Antiquities Act, to reduce the size of monuments created by past presidents. Chutkan could reinstate the mining and development bans. But by the time she rules, the Bureau of Land Management and the U.S. Forest Service might already have begun reducing vegetation across the land.

The creation of both monuments by Democrats stoked outrage in rural, deeply Republican Utah, and Trump's downsizing was seen by many conservatives as a victory against political pandering to liberals.

American taxpayers eventually paid about $19 million to buy up coal leases after the Grand Staircase was created because mining and development is banned in national monuments. Taxpayers also paid $50 million to the state and transferred developable federal lands to the Utah School and Institutional Trust Lands Administration in exchange for monument inholdings.

The new Trump land management plan would allow mining again in those taxpayer buyout areas.

Leland Pollack, a commissioner in Garfield County in the area of southern Utah that includes Grand Staircase, applauded Trump's approach to protecting land while expanding access to grazing, mining, logging and recreation. He dismissed the suggestion that the lawsuits should be allowed to run their course—possibly even up to a conservative-dominated U.S. Supreme Court—before finalizing the new management plans.

"You can't control these lawsuits," he said, echoing the Interior Department's Hammond. "You've just got to go forward."

But Willie Grayeyes, a Navajo who's advocated for decades to protect the Bears Ears region for cultural and religious practices, disagreed. The fight to preserve the monuments is far from over.