With this approval, the company will be able to operate the mine for an additional ten years until Nov 2025.
NRC said that the approval comes after its staff reviewed the technical, safety and environmental aspects of the project.
The agency added: "A Safety Evaluation Report published in August 2014 found the facility could continue to operate safely.
"An Environmental Assessment published in the Oct. 30 Federal Register found there would be no significant environmental impact from continuing operation for another 10 years."
However, environmental groups have raised concerns over operation of the mine, claiming that water with dissolved uranium has affected aquifers across the state line in South Dakota, reported Chadron radio station KQSK.
The license renewal application was filed with the NRC in November 2007.
