FLAGSTAFF, Ariz. (AP) — A coalition of conservation groups announced Thursday that it's appealing a court decision that opens the door to new uranium mining 6 miles from Grand Canyon National Park's South Rim.

A federal judge ruled April 7 against environmentalists in their fight to halt a uranium mine south of the Grand Canyon that they say will harm people, water and wildlife in the region.

The Sierra Club, the Center for Biological Diversity and Grand Canyon Trust have challenged the U.S. Forest Service's decision to allow Energy Fuels Resources Inc. to reopen the mine.

The lawsuit filed in 2013 alleged that the Forest Service violated federal law in allowing the Canyon Mine to move forward and didn't adequately consult with the Havasupai tribe over a sacred site near Tusayan.

The tribe also has filed a notice of appeal of the ruling by U.S. District Judge David Campbell in Phoenix.

The Forest Service approved a plan of operation for the Canyon Mine in 1986, and officials have argued that it remains valid, along with the mining claims owned by Energy Fuels Resources.

The company plans to restart the mine this spring, shifting employees from a mine north of the Grand Canyon after resources there are depleted.

The coalition of conservation groups alleges that Canyon Mine threatens tribal cultural values, wildlife and endangered species and has the potential to contaminate the aquifers and streams that sustain the Grand Canyon and Colorado River with toxic uranium-mining waste.

"At a minimum, the Forest Service should look at the harm this mine will cause to the groundwater and ultimately the waters in Grand Canyon National Park and consider the last 30 years of science and additional information we have about uranium mining's impacts to our natural and cultural resources," Sandy Bahr, director of Sierra Club's Grand Canyon Chapter, said in a statement.

Energy Fuels officials have said there's no need to worry because a state permit requires that dust be monitored and controlled, no homes are nearby, and the dust isn't highly radioactive.