The American Exploration & Mining Association was joined by a coalition in filing a challenge last Friday in the Wyoming district court.
The company's Flat gold project is located 40 km north of the giant Donlin gold project.
The world’s largest producer of uranium is increasing its mining tax on the nuclear fuel by at least 50% next year.
There are some 10,000 mining claims in Grassy Narrows’s interim area of interest for over more than 2,850 sq. km in the province’s far northwest.