Resolution Copper
| Company type | Joint venture |
|---|---|
| Industry | Mining |
| Founder | Rio Tinto and BHP |
| Headquarters | Superior, Arizona , United States |
Area served | United States |
| Products | Copper, molybdenum |
| Owner | Rio Tinto and BHP |
| Parent | Rio Tinto and BHP |
| Website | resolutioncopper |
Resolution Copper (RCM) represents a collaborative enterprise between Rio Tinto and BHP, focused on developing and managing an underground copper extraction operation near Superior, Arizona, USA. The initiative aims to exploit a deep porphyry copper deposit located beneath the defunct Magma Mine. According to Rio Tinto, the inferred mineral resource comprises 1.624 billion tonnes with an average grade of 1.47% copper and 0.037% molybdenum at significant depths.[1] The site is situated above Oak Flat, a region considered sacred by several Apache tribes.[2] It holds one of the continent’s most substantial copper reserves.[3] Since the passage of the 2015 National Defense Authorization Act, the project has faced opposition from Native American groups and environmental advocates.[2]
Overview
The Resolution Copper project is projected to be a $64 billion investment with an operational lifespan of approximately 60 years,[4] expected to supply around 25% of the United States’ copper demand over multiple decades.[3]
Investment
By 2012, nearly $1 billion had been invested in the Superior project by Resolution Copper, with plans to allocate an additional $6 billion for mine development contingent upon federal land exchange approval. Following delays, the annual expenditure was reduced from $200 million in 2012 to $50 million in 2013.[5] By early 2023, cumulative spending on exploration and preparatory activities exceeded $2 billion.[6]
Additionally, Resolution Copper holds mineral rights acquired from ASARCO for the Superior East deposit, another significant deep porphyry copper site located approximately one mile east.[7][8]
Project history
Progress on the project has been impeded pending a proposed land swap agreement with federal authorities. Resolution Copper suggested trading environmentally sensitive Arizona lands for control of the federal Oak Flat parcel, which encompasses the protected Oak Flat Campground and several popular climbing locations.
In May 2009, legislation to finalize this land exchange was introduced by Arizona Democratic Representative Ann Kirkpatrick, garnering support from Arizona’s Republican senators. In 2013, Representative Paul A. Gosar sponsored the Southeast Arizona Land Exchange and Conservation Act of 2013 (H.R. 687; 113th Congress), which aimed to preserve the Apache Leap Cliffs under federal management and required Resolution Copper to relinquish mining rights and transfer ownership of 110 acres adjacent to the cliffs back to government control.
A provision included as a rider in the 2015 National Defense Authorization Act, championed by Senators John McCain and Jeff Flake, incorporated elements from the stalled land exchange legislation. This enabled Resolution Copper to acquire 2,422 acres of National Forest land in return for conveying 5,344 acres of private property. The mine’s footprint impacts an area designated in 1955 by President Dwight D. Eisenhower that holds spiritual significance for the San Carlos Apache Tribe, including Oak Flat Campground and Apache Leap cliffs.
The initial land transfer report was issued during the Donald Trump administration, scheduling the transfer for March 11, 2021. However, the subsequent Joe Biden administration withdrew this plan on March 2 to allow for increased public and Indigenous consultation. On March 18, 2021, Democratic Representative Raúl Grijalva reintroduced the Save Oak Flat Act intending to repeal the mandated land transfer.
In June 2022, the 9th US Circuit Court of Appeals affirmed a lower court decision permitting the land transfer, underscoring federal authority despite concerns regarding religious impact. Later that year, the full court agreed to rehear the case en banc as Rio Tinto continued outreach efforts with affected tribal communities. In March 2023, officials from the US Forest Service stated they did not acknowledge an 1852 treaty as conferring Apache rights over the copper-rich territory.
On March 1, 2024, a close 6-5 decision by the Ninth Circuit ruled that transferring the land did not place a "substantial burden" on religious practices of the San Carlos Apache Tribe. The organization Apache Stronghold subsequently petitioned the U.S. Supreme Court seeking reversal of this ruling.
On May 9, 2025, a federal judge temporarily halted attempts initiated during the Trump administration to transfer ownership of Oak Flat lands, citing probable success by Apache groups in Supreme Court appeals. Nevertheless, on May 27, 2025, the U.S. Supreme Court declined Apache Stronghold’s appeal, permitting Resolution Copper’s acquisition of Oak Flat land to proceed—marking a pivotal advance toward developing one of America’s largest untapped underground copper reserves.
Reactions
Opposition to the Resolution Copper land exchange has come from several groups, including the San Carlos Apache Tribe, the National Audubon Society in Tucson, the Sierra Club's Grand Canyon Chapter, and the National Congress of American Indians. Their objections focus on potential negative effects on adjacent regions and the desecration of sacred tribal sites. In 2014, then-Secretary of the Interior Sally Jewell conveyed strong disappointment regarding the land-swap clause, emphasizing its failure to respect lands held sacred by nearby indigenous communities.
Jodi Gillette, serving as Special Assistant to the President on Native American Affairs, indicated that the Obama administration aimed to engage with Rio Tinto, Resolution Copper’s parent organization, to ensure cooperative efforts with tribal groups in safeguarding these culturally significant locations.
See also
- Peak copper
- Copper mining in Arizona
- Copper mining in the United States
- Magma Arizona Railroad
- Twin Metals mine
- Pebble Mine
- Oak Flat: A Fight for Sacred Land in the American West
Further reading
- Manske, Scott & Paul, Alex (2002) Abstract "Geology of a Major New Porphyry Copper Center in the Superior (Pioneer) District, Arizona" Economic Geology v.97 no.2 pp. 197–220.
External links
- ↑ Cite error: Invalid
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<ref>tag; no text was provided for refs namedict - ↑ Resolution Copper Mining "Letter to the community", November 30, 2012
- ↑ Krauss, Clifford; Kalifa, Tamir (2023-01-27). "A Copper Mine Could Advance Green Energy but Scar Sacred Land". The New York Times. Retrieved 2023-01-27.
- ↑ Bureau of Land Management lead file AMC60069
- ↑ Sell, James D. "Porphyry Copper Deposits of the American Cordillera". "Arizona Geological Society Digest 20" 1995. pp. 373–95.
- BHP
- Copper mines in Arizona
- Mining in Arizona
- Pinal County, Arizona
- Rio Tinto (corporation) subsidiaries
- Underground mines in the United States
- Environmental justice in the United States
- Environmental controversies
- Environmental protests in the United States
- Indigenous peoples of North America and the environment
- Indigenous rights in the United States
- Land defender
- Environmental racism in the United States