(AP) -- The U.S. Department of Interior has outlined four proposals to address mining around the Grand Canyon, one of which would set aside 1 million acres from any new claims.
Interior Secretary Ken Salazar temporarily withdrew the acreage in 2009.
The proposals released Thursday also include taking no action and two partial withdrawals.
The draft environmental study identifies the proposal to set aside 1 million acres as the "proposed action," but Interior officials say they don't prefer one proposal over the others.
As many as 10,000 mining claims exist on federal land near the Grand Canyon for all types of hard-rock exploration. And some 1,100 uranium mining claims are miles from the park's boundaries.
Should any of the land be withdrawn, companies would need to prove they have valid existing rights to those claims before mining there.
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