US Rep. Raúl Grijalva (D-AZ) introduced legislation Monday to prevent the transfer of sacred Apache land to a copper mining company, offering permanent reassurance in a scenario that has posed a looming threat to the area since 2014.

Oak Flat, located in Arizona’s Tonto National Forest, is holy ground for the San Carlos Apaches, who come to pray and hold traditional ceremonies there. In 2014, the land was transferred to foreign mining company Resolution Copper in a last-minute addition to the 2015 defense budget bill. At the urging of the Trump administration, the environmental impact survey (EIS) was published ahead of schedule on January 15, triggering the land transfer. Apache Stronghold, a group of Natives and non-Native allies, filed an emergency lawsuit to contest the rushed process. President Joe Biden’s administration then withdrew the EIS, postponing the deal indefinitely.

Grijalva’s Save Oak Flat Act would repeal Section 3003 of the 2015 National Defense Authorization Act, which contains the clause granting the transfer. This bill cites several reasons for the land swap being invalid. For one, the deal was introduced twice as separate, independent legislation, and was rejected each time. There was also not enough time to propose an amendment to remove Section 3003.

The bill also notes that the deal allegedly violates the trust responsibility agreement between indigenous nations and the federal government, which requires the federal government to meaningfully consult with affected tribes before making decisions that impact them. Additionally, it also creates an impermissible scheme that allows a potentially destructive project to go ahead regardless of the outcome of the EIS and negotiations with affected communities.

If passed, this legislation would save Oak Flat from irreparable damage. Resolution Copper plans to use a technique called block caving that hollows out land deep under the ground, eventually causing the entire site to collapse in on itself. The mining process would also produce toxic waste that could contaminate nearby land and water sources.

Sen. Bernie Sanders (D-VT), author of the Senate companion bill, said, “It is wrong that a backroom deal in Washington could lead to the destruction of a sacred area that is so important to so many. We must defend the hundreds of thousands of Americans who are standing in opposition to this giveaway of our natural resources to foreign corporations.”