FLAGSTAFF, Ariz. — The federal government has approved a plan to clean up the most badly contaminated uranium mine site on the Navajo Nation.

The U.S. Environmental Protection Agency announced the plan Thursday to remove 1.4 million tons of contaminated soil from the former Northeast Church Rock Mine near Gallup, N.M., at a cost of $44 million. The mine operated from 1967 to 1982 and has long topped the priority list for cleanup on the vast reservation.

"This is an important milestone in the effort to address the toxic legacy of historic uranium mining on the Navajo Nation," said Jared Blumenfeld, administrator for the EPA's Pacific Southwest Region in San Francisco.

The mine site includes two underground uranium shafts, waste piles, surface ponds and buried waste, contributing to the 4 million tons of uranium ore that was mined from the reservation over four decades. Rain and flash floods have carried the radium-contaminated soil from the mine down an arroyo where children play and livestock graze, and the wind blows it into people's yards.

Clancy Tenley, associate director for tribal programs at the EPA in San Francisco, said the soil will be placed in a lined repository and capped, atop tailings at an adjacent mill site owned by United Nuclear Corp. The EPA is finalizing an agreement with the corporation's parent company, General Electric Co., for the cleanup that will take several years, beginning next summer.

The EPA considered more than a dozen sites to stockpile the waste but said storing it at the mill site also owned by United Nuclear Corp. would be the most cost-effective and could be implemented in a reasonable time frame while protecting human health. Exposure to elevated levels of radium over a long period of time can result in anemia, cataracts and cancer.

"If all goes well, seven years from now the project will be complete," Tenley said.

About 10,000 tons of waste that has higher concentrations of radium will be shipped to Utah for reprocessing or disposal, Tenley said. General Electric said in a letter to the EPA that it didn't believe off-site disposal was necessary, given other waste from other nearby mines could be sent to the repository, dwarfing any potential risk with the more contaminated waste. But General Electric said it would defer to the EPA.

Creating a mound up to 10 feet high that's filled with contaminated waste wasn't the first remedy of choice for the residents or the tribe, who said they would rather see the soil hauled off far from the reservation. But knowing the design phase will take three years and that an Albuquerque, N.M.-based research group that works closely with Navajo uranium issues has been hired as a technical adviser on the project has provided some comfort.

"There's some assurances we got that led us to be supportive of the remedy," said Stephen Etsitty, executive director of the tribe's EPA. "Part of the assurances are that the (Navajo) Nation is going to be heavily involved in the design and engineering as we begin this work."

Larry King, who worked as an underground surveyor at the Northeast Church Rock Mine in the 1970s and early '80s, said he's concerned that the contaminated soil could weigh heavily on the existing mill tailings cells causing the liner to break and groundwater to be spoiled. The EPA said it evaluated the concerns and found that the soil can be placed on the tailings without affecting the groundwater or stability of the tailings.

Still, King said, "It will be in the back of everybody's mind that we can't really spend too much time standing here, because that's where the waste pile was and the radiation."

General Electric has done smaller cleanup projects in the area — demolishing and rebuilding a structure in 2007 and removing 40,000 tons of contaminated soil last year. Nearby residents were temporarily moved during the last cleanup, and Tenley said they will be asked again if they'd like to relocate, either to hotels or by receiving a cash settlement to buy a home.

King said he's not sure he'll be offered alternative housing, but he sounded doubtful he'd take it.

"I have to think about my livestock, my livelihood," said the 54-year-old. "This is where we were raised."