Rosemont Mine project in southern Arizona faces pushback over water storage

Despite widespread resistance from the City of Tucson, Pima County, multiple environmental groups and Indigenous tribes throughout southern Arizona, Canadian-based Hudbay Minerals continues to push its Rosemont Mine project through roadblocks hoping to get final approval.

While state and federal regulators — as well as 19th Century mining law — seem to side with the global mining interest intent on creating what is expected to be the third-largest mining project in the U.S., local officials have made it clear they have little interest in accommodating the process in any way.

The latest in a battle that has been ongoing for more than 15 years involves Tucson, Hudbay and the Central Arizona Project (CAP) in a standoff about use of water storage capacity at the Pima Mine Road Recharge Project (PMRRP), a series of water storage basins located near Sahuarita, about 15 miles south of Tucson.

CAP is the agency in charge of distributing Colorado River water to Maricopa, Pima and Pinal counties, serving more than 5 million people — some 80% of the state’s population. The 336-mile system of aqueducts, tunnels, pumping plants and pipelines stretches from Lake Havasu to the PMRRP and is “the largest single resource of renewable water supplies in Arizona,” CAP boasts on its website.

The PMRRP is a facility jointly owned by CAP and Tucson that is permitted to recharge up to 30,000 acre-feet per year (about 10 billion gallons) and is largely maintained by the city. A single acre-foot of water equals 325,851 gallons, or the amount of water needed to cover an acre of land — roughly the size of a football field — a foot deep. 

Recharging replenishes the aquifer by allowing water stored at the facility to “percolate” through the rocks and sand below where it is naturally filtered and stored for future use.

At issue is a recent decision made by CAP to allow Hudbay/Rosemont to store 1,124 acre-feet of water per year for 10 years at the facility.

The process began in October 2021, when storage was allocated to permitted users. At the time, the City of Tucson was unaware of the Hudbay request. When city leaders learned of the request at the October CAP meeting, their position was clearly communicated to CAP. In early January, over the objections of Tucson, the agency’s governing board voted 7-4 to approve the Rosemont agreement.

As a partner in the venture, Tucson owns “first right of refusal” over capacity and has announced its intention to use it.

The line between Rosemont and Tucson was clearly drawn at the Jan. 6 meeting, as CAP board members debated their roles in the process and whether the board should base its decisions on intended water use for its partners.

The Central Arizona Water Conservation District (CAWCD), the body formed to manage CAP resources, is led by a non-partisan, 15-member board elected from the three counties in its service area.

Board Member Marie Pearthree, from Pima County, suggested that it is up to the City of Tucson to exercise its right of first refusal and not the board’s job to “pick winners and losers,” which could damage its “credibility and effectiveness.”

“If we were to vote against this agreement, then we would be picking who can store water and who cannot,” she said. “That would conceivably set a pretty bad precedent with the board possibly being perceived as engaging in arbitrary or capricious decisions.”

CAP attorney Greg Adams agreed.

“I would say… that would be unprecedented,” Adams said. “We have never done that, and it would be this board picking and choosing winners or losers as far as entering into a water storage agreement, which we have not done in the past.”

Board Chairman Terry Goddard cautioned against board members using such rhetoric and to be mindful of adjudicating the issue in its discussions.

“I would like to caution the board, as a general matter, against using such colorful language, because you’re asking our distinguished counsel to basically draw some final legal conclusions,” he said. “That’s not fair.”

Board Member Mark Lewis, of Maricopa County, voiced his support for Rosemont’s use of “a fully funded taxpayers asset.”

“I would view negatively any operator who would attempt to utilize an asset when there’s another opportunity for another user to use that asset to its full extent, especially since it was property tax-funded, appropriated for by the legislature,” Lewis said. “I would also dissuade others from playing and gaming the system for whatever political agenda that might pop up.”

Not everyone on the board agreed.

Alexandra Arboleda, from Maricopa County, said she has concerns about the agreement in light of community resistance to the Rosemont Mine project.

“Because we have so much opposition in the local community, it seems like this is something that we really need to evaluate,” she said. “If we’re acting as the designated agent for the City of Tucson and the city is opposed to this, how can we do that?”

Adams explained that CAWCD can approve the agreement and its decision is based solely on whether or not there is sufficient capacity and if Rosemont has “CAP entitlement.”

“Legally, we have the sole discretion, but this board has to consider to what extent we should take into account our partnership with the City of Tucson,” Arboleda said. “They’re concerned that this is going to affect the quantity and quality of their water supply. … If our partner in this storage facility has concerns … that is something we should look into further.”

Tucson Assistant City Attorney Chris Avery told the board that the city’s resistance to the Rosemont agreement is “total and complete,” and reminded the board members of the “productive partnership” the two jurisdictions have had in the development and maintenance of the PMRRD. He also expressed hope the relationship would continue to be cordial in the future.

“We oppose the Rosemont Mine and we oppose the issuance of this storage facility,” he said. “Once the storage permit is issued for Rosemont, should the board decide to do that, the City of Tucson, mayor and city council have made it clear that we intend to exercise our right of first refusal in order to prevent Rosemont from using this facility.”

Matt Bingham, director of legal and public affairs for Hudbay, told the board that Hudbay was using the excess capacity in order to be “responsible water stewards,” and said it would be unfortunate if “politics” influenced the board’s decision.

“Everyone recognizes the benefits of recharging water,” he said. “We need to keep politics out of decisions related to our region’s water security and do what’s in the best interest of the community. We believe that approving this storage agreement is the right thing to do for Arizona.”

Bingham said that Hudbay’s modern mining techniques would allow the international mining corporation to “produce twice the amount of copper with the same amount of water compared to traditional copper mines,” and that they intend to put back more than they take out.

“Despite what you may have heard today, or may have heard elsewhere, Rosemont will be a net benefit to the water inventory of southern Arizona,” he said. “Not only through our CAP recharge activities, but through the purchase of existing surface water rights and transferring those into conservation uses.”

He said that Rosemont has already stored more than 42,000 acre-feet of CAP water in the Tucson Active Management Area. And the agreement to store water in PMRRD won’t determine whether the mine is ultimately built.

“It would be truly unfortunate if a mine was ultimately constructed but the mitigation that was offered to offset the impacts was rejected,” he concluded.

In the end, the board voted 7-4 to approve Hudbay’s application.

The project

The Santa Rita Mountains are located about 40 miles south of Tucson, one of five “Madrean sky islands,” in the region. The range is home to Mount Wrightson, the highest point in the Tucson area, and also Madera Canyon, purported to be one of the world’s premier birding areas. The Smithsonian Institution’s Fred Lawrence Whipple Observatory is located on Mount Hopkins.

It is also home to rare jaguar habitat, which was the subject of one lawsuit in 2017.

The proposed Rosemont mine is located on the east side of the mountain range. Should it get final approval, the mine would have a 19-year lifespan and would leave a mile-wide, half-mile deep crater. The ensuing mine waste would fill washes and canyons that are important pieces of the watershed.

Hudbay would also have to build infrastructure, including roads and a processing plant, and identify land to dump leftover mine waste, known as tailings.

“They have to build roads and whatever kind of infrastructure they need up there, and they’ve already made quite a mess on the west side, it’s very disheartening,” said Gayle Hartmann, president of Save the Scenic Santa Ritas, a watchdog organization dedicated to stopping the project. “It certainly isn’t as bad as what would happen if they actually started the mine, but it looks bad. We almost think that maybe one of their schemes was to do as much damage as possible, and then maybe people will give up.”

The project has been in the works in some form since the mid-1990s, and the property in question had several owners prior to its purchase by Hudbay, including Augusta Resource Corp. and Asarco.

There have been many lawsuits over water quality issues and wildlife habitat from environmental organizations including Save the Scenic Santa Ritas, the Center for Biological Diversity, the Arizona Mining Reform Coalition and the Sierra Club. The courts have largely put the brakes on the project, although the U.S. Forest Service has allowed it to move forward because of interpretations of an 1872 federal mining law that favors mining interests over environmental concerns or public opinion.

In July 2019, Judge James A. Soto of the U.S. District Court for Arizona overturned the Forest Service’s approval of the mine, which Hudbay claims would create 500 full-time jobs at high wages and 2,500 construction jobs through the life of the mine.

Citing the “arbitrary and capricious actions of the Forest Service,” Soto granted a judgment in favor of Save the Scenic Santa Ritas and the tribes who had sued.

According to the lawsuit, there would be costs associated with the project, such as “disturbed Indigenous cultural resources,” including burial grounds of the Tohono O’odham Nation, Pasqua Yaqui and Hopi tribes.

Additionally, excavation would directly affect approximately 955 acres of land.

The lawsuit claims that, after Rosemont has completed extraction of the copper, molybdenum, silver and gold, what would be left would be a circular pit measuring approximately 3,000 feet deep and 6,000 feet in diameter. Excavation would “penetrate the wall of the groundwater table lying beneath the Santa Rita Mountains and (Rosemon)] will need to pump groundwater out of the pit to continue their mining operations.”

After mining operations end in 20 to 25 years, Rosemont would turn off the pumps and the pit would fill with toxic groundwater, leaving an environmental disaster in its wake for future generations to clean up.

Approximately 1.2 billion tons of waste would be generated, along with approximately 700 million tons of tailings dumped on approximately 2,447 acres of the Coronado National Forest. The mine would ultimately impact approximately 3,653 acres of the Coronado National Forest.

Hudbay appealed the ruling and believes that “the Court misinterpreted federal mining laws and Forest Service regulations as they apply to Rosemont.”

“The metal from Rosemont will be a vital part of technology in daily life, the green economy and Arizona’s future,” Hudbay said in a statement when the ruling was issued. “Rosemont is striving to raise the bar for what it means to safely and sustainably mine copper and other essential minerals – to minimize impacts to the landscape and water and to enrich partner communities in ways that outlast the course of mining operations.”

The case went to the 9th U.S. Circuit of Appeals in 2020, but the appellate court hasn’t yet ruled. But as Hudbay awaits a decision, it has begun exploratory drilling at three locations on the western slope of the Santa Ritas on property it owns there.

Last September, Hudbay released an announcement that they would be looking into the viability of “Copper World,” three open-pit mines under development on the west side of the Santa Ritas.

“On the west side, it’s a little less clear because we don’t have any mining plan, so we don’t really know,” Hartmann, of Save the Scenic Santa Ritas, said. “There apparently is not nearly as much ore on the west side. In fact, we think that a lot of their work there may just be what we call ‘mining for investors,’” which is more about increasing stock prices than mining.

Hartmann believes mining on the west side would be harmful to the Santa Cruz basin, because after Rosemont “washes the rocks,” the water on the properties would flow back into the watershed should dams created to hold it back fail.

“When that flows back into the Santa Cruz, it becomes toxic water if their dams break,” she said. “Then you have just another source of toxic water in the Santa Cruz basin.”

The City of Tucson responds

Vowing to stand up to Hudbay to protect southern Arizona’s environment and water supplies, the Tucson City Council addressed a potential lawsuit at its Feb. 8 meeting.

“I want to make it clear today to any of the Hudbay guys in Canada watching: You will never build your mine if I have anything to say about it,” Councilman Paul Cunningham said. “There’s 15 different things that I could say, like, ‘what about an actual extraction tax,’ ‘what about being able to charge them for the water out of the aquifer,’ but at the end of the day, what it does, the net positive for our region and for Tucson, is nil. They could give us a hundred billion dollars for water fees and it wouldn’t game out.”

Avery, the assistant city attorney, informed the council that the city was within its rights to take some kind of legal action to stop Hudbay’s use of PMRRP, under the terms of an intergovernmental agreement adopted in the spring of 2000.

While the action can be seen as largely symbolic, the Tucson council has staked out its position and will discuss its options during an executive session at its Feb. 23 meeting.

Councilman Steve Kozachik has been a vocal opponent of the mine for many years and is fully supportive of any actions that can slow the mining behemoth.

“I don’t know that this is going to be a significant roadblock, but it’s certainly consistent with our message,” he told the Arizona Mirror. “I don’t want to do anything to benefit Rosemont. The message is very clear: We don’t want you here.”

Tucson Mayor Regina Romero expressed disappointment at the CAP decision, given sustained resistance to the project.

“I’m frankly very, very disappointed that the CAP board voted in favor of storing this Rosemont Mine water,” Romero said. “Our Tohono O’odam Nation and Pasqua Yaqui Tribe are very clearly against Rosemont, as well as many environmental groups in the community.”

The fight continues

As Hudbay awaits action by the courts, environmentalists and others aiming to stop the Rosemont Mine continue to fight and wait for processes to play out, while Hudbay keeps digging around in the desert.

Hartmann said the two main arguments for copper mining in the state are jobs and the need for copper, but believes they don’t hold water.

“We’ve looked at where all the earnings come from in Pima and Santa Cruz counties, and mining is an insignificant part of it,” she said. “Even if you took them at face value, their 500 jobs, it’s less than 1/10 of 1%: It’s a tiny, tiny amount.”

As to the need for copper, there are mines that were abandoned because of a lack of economic viability, such as the San Manuel Mine that was shut down in 1999 due in large part to a global drop in copper prices. Recycling copper is another option that can reduce the need for destructive mining practices.

Additionally, Hartmann says there are opportunities to mine copper left behind in tailings, as mining technology has advanced to the point that copper left over from less efficient practices is sitting in huge piles all over the state.

“It certainly seemed like this notion that we have to mine the Santa Ritas to get copper is kind of a spurious argument,” Hartmann concluded.

***CORRECTION: An earlier version of this story incorrectly identified one of the groups opposed to the Rosemont Mine as “Saving the Scenic Santa Ritas.” The group’s name is “Save the Scenic Santa Ritas,” and has been corrected throughout the story.