Communities in Kane County and the town of Fredonia, Ariz., just across the state line, believe the decision will have a devastating effect on a region already in economic dire straights.
Environmental groups and critics of mining, such as former New Mexico Gov. Bill Richardson, have said mine-related waste threatens the region's land, wildlife and drinking water. Existing mining claims in the area, known as the Arizona Strip, will still be honored, Salazar said.
Salazar directed the Bureau of Land Management to list withdrawal of the area from mining as the "preferred alternative," he said.
"This alternative, if ultimately selected, would ensure that all public lands adjacent to Grand Canyon National Park are protected from new hard-rock mining claims, all of which are in the watershed of the Grand Canyon," Salazar said.
Prospectors have staked about 3,000 claims, said Bob Abbey, director of the Bureau of Land Management.
None of those have been validated, according to Roger Clark, air and energy program director for the Grand Canyon Trust, an advocacy group focused on the conservation of the Grand Canyon and Colorado Plateau.
Clark said in an interview that he believes the proposed ban is "a done deal" and that "it's just a matter of making it official."
"A 20-year ban will begin to reverse the toxic legacy that uranium mining has imposed," Clark said.
The Interior Department said it expected to complete the environmental review this fall.
Monday's order doesn't affect current uranium mining, such as the Arizona 1 mine operated by Denison Mines Corp. of Toronto.
In 2009, Salazar called for a two-year halt from all new mining claims through July 20. Today's six-month "emergency withdrawal" extends that though Dec. 20, when the final record of decision is scheduled to be set.
Environmentalists, American Indian tribe representatives and public figures such as Richardson, a Democrat, and Theodore Roosevelt IV, great-grandson of Republican President Theodore Roosevelt, asked President Barack Obama this month to extend the Grand Canyon mining moratorium.
In Kanab, the Kane County Commission was not happy with Salazar's announcement. Commissioners said Salazar's decision was similar to former President Bill Clinton's announcement in 1996, also at the park's South Rim, of the creation of the Grand Staircase-Escalante National Monument.
In a news release, the commission said the move by Salazar could mean the loss of as many as 4,000 jobs in Kane and surrounding counties in Utah and Arizona, and possibly cost $30 billion to the area's economies.
The commission said the decision will affect communities that already struggle economically and, in some cases, have significant numbers of residents below the poverty level. The loss of mining-related jobs would have a huge economic impact on the area of the country where household incomes are substantially below the national average and unemployment rates high in some of the effected counties.
The commission and officials in other southern Utah and Arizona counties expressed their concerns in a letter to Obama.
Douglas Heaton, chairman of the Kane County Commission, said Salazar's approach was the same as the one Clinton took to create the Grand Staircase and blamed Monday's decision on environmentalists.
"Salazar's efforts are purely for political reasons, to satisfy demands from anti-development environmentalists who have always opposed mining on the Arizona Strip," he said. "We'll continue to fight to improve the economic benefits for Kane County and work to make America more energy-independent."
The decision was also frowned upon Monday at the Buckskin Tavern in Fredonia, Ariz., a sister community to Kanab and whose economy is supported partly by the mines already operating.
Bill Terrel said there is no reason to hinder mining on the sparsely populated Arizona Strip, which is administered by a BLM office in St. George and adjacent to the national park's North Rim visitor center.
He said the underground mining operations are so small, "you can't even tell where they have been or where they are."
Terrel said he is not buying the argument that the mines present a threat to wildlife because the ore is located 200 feet underground.
"Hell, even snakes don't go that deep," he said.
He blamed Salazar's decision on environmentalist "tree huggers," who he suggested should "start hugging cactuses."
He said the environmentalist have had a devastating effect on the area economy over the years, blaming them for the loss of oil refining in the area, energy development and demise of the timber industry.
Zerue Jarvis wondered how uranium ore 200 feet underground could affect water quality and said the issue demands a good dose of "common sense."
"Water is going to leach through to [the ore] if they mine it or not," she said.
She also blamed Monday's announcement on liberals and environmentalists.
"They [environmentalists] are taking over," she said. "If something is taken away [like uranium mining] then something should be given back to take its place."
Bloomberg News contributed to this story.