A battle is looming over whether to lift a 20-year moratorium on uranium mining on federal lands surrounding Grand Canyon National Park/NPS

Longstanding efforts to expand uranium mining on lands rimming Grand Canyon National Park are poised to be rekindled thanks to a move by the U.S. Forest Service, though a Democratic congressman is hoping to block the efforts by legislation that would set aside roughly 1 million acres as a national monument.

Forest Service officials, in response to a request by President Trump that they review regulations that “potentially burden the development or use of domestically produced energy resources, with particular attention to oil, natural gas, coal, and nuclear energy resources," have pointed to ending a 20-year moratorium the Obama administration imposed in 2012 on uranium mining on about 1 million acres of Forest Service and Bureau of Land Management lands north and south of Grand Canyon.

U.S. Rep. Raúl M. Grijalva, an Arizona Democrat, late last week requested that House Natural Resources Committee Chairman Rob Bishop, a Utah Republican, schedule a hearing on H.R. 360, which calls for a Greater Grand Canyon Heritage National Monument.

Rep. Grijalva said he first requested a hearing on the bill in January, which Chairman Bishop ignored.

In his letter to Chairman Bishop, the Democrat said that ending the moratorium after only five years "without scientific or public review, would be irresponsible and threaten a watershed that provides drinking water to more than 20 million Americans. In addition to providing critical ecosystem services, the Grand Canyon contains a tremendous array of cultural resources and is sacred to Native Americans throughout the region. The National Congress of American Indians and the Inter-Tribal Council of Arizona support H.R. 360 and deserve an opportunity to share their views with Congress prior to any change in the management of the area."

"If the scientific analysis underlying the Forest Sevice's recommendation is sound," Rep. Grijalva added, "the Trump administration and House Republicans should welcome an opportunity to share that analysis with the public."

The Bureau of Land Management in October 2011 prepared an extensive environmental impact statement on the proposed withdrawal of the acreage from new uranium mining. That study examined the impacts expanded uranium mining might have on the surrounding watershed and the Grand Canyon. The lands in question are located in three parcels: two north of the national park on BLM Arizona Strip lands and the North Kaibab Ranger District of the Kaibab National Forest, and one south of the Grand Canyon on the Tusayan Ranger District of the Kaibab National Forest.

“The Grand Canyon is an iconic place for all Americans and visitors from around the world,” said then-BLM Director Bob Abbey. “Uranium remains an important part of our nation’s comprehensive energy resources, but it is appropriate to pause, identify what the predicted level of mining and its impacts on the Grand Canyon would be, and decide what level of risk is acceptable to take with this national treasure. The preferred alternative would allow for cautious, continued development with strong oversight that could help us fill critical gaps in our knowledge about water quality and environmental impacts of uranium mining in the area.”

There has been public support in Arizona for the ban. More than 200 business owners in the state signed a "postcard" to Ken Salazar, Interior secretary at the time, asking him to support the moratorium.