Hudbay Minerals Inc. will begin clearing and grading land this month for its goal of building five open-pit mines on the west slope of the Santa Rita Mountains, it told Pima County officials.
Rosemont Copper, Hudbay’s Arizona-based subsidiary, “anticipates starting clearing, grading, stockpiling and other earthwork activities related to the construction of tailings and waste rock facilities” in April on its private land on the west slope, Hudbay Vice President Javier Del Rio wrote to the Pima County Regional Flood Control District on March 10.
The company also plans to start seeking permits later this year from “various state agencies” to allow construction of its entire Rosemont Copper World project on the west slope, the letter said. Besides waste rock and tailings facilities, the company also plans a heap leach pad, the multiple open pits and some kind of plant site, it wrote.
“The initial work consists of ground preparation activities for the tailings and waste rock storage areas on Rosemont’s private property. As always, Hudbay will take great care to ensure that we minimize disturbances to the environment and comply with all federal, state and local requirements,” Hudbay said in a statement to the Star on Monday.
The company has no specific construction start date yet, it said Monday.
The company will need three state permits to build Copper World on the west slope, it told the Star. Those include an aquifer protection permit, an air quality permit, and a surface water quality permit for stormwater runoff from the site, “in addition to many other approvals prior to beginning operations,” said Hudbay, without elaborating.
A set of maps that Hudbay sent the county shows five open pits on the west slope, two more than the company had previously shown on earlier maps of possible west slope mining plans in the mountain range southeast of Tucson. The maps also show the site to be directly east of Green Valley.
In responding to Hudbay’s letter to Pima County, an environmental law firm representing three Arizona tribes sent the mining company a notice Monday that it intends to file suit to block construction activity on the west slope. The notice said grading and clearing activities there would violate the federal Clean Water Act’s prohibition of “any unpermitted discharges” into federally regulated washes.
Under federal law, however, the tribes can’t file suit until 60 days after giving notice, meaning they can’t seek an injunction to block construction until well after it’s likely to start.
A developer of a mine or of housing must obtain a Clean Water Act permit if the federal government determines the construction work would require depositing fill material in neighboring washes that are deemed eligible for federal regulation.
Because of recent, conflicting federal actions and a 2021 federal court ruling on the issue, it’s not clear at this time if the ephemeral washes on the Copper World site will be regulated or not. The Army Corps of Engineers hasn’t yet responded to questions from the Star about Hudbay’s likely activity at the site.
In response to questions from the Star, Hudbay denied its planned activities would damage federally regulated washes.
“The site preparation work is being conducted exclusively on Hudbay’s private property where none of the dry washes have ever been designated as” Waters of the United States subject to regulation, the company said. The area includes Helvetia,” a historic mining district with dozens of old mines, exposed workings, and the remains of a 19th century smelter and corresponding slag pile.”
Additionally, the company said, “Hudbay has all approvals required for this initial site preparation work on Rosemont’s private property.”
The notice of intent to sue said, “The proposed mine site contains a dense network of ephemeral streams that qualify” as federally regulated waters, protected by the Clean Water Act.
The notice was filed by the Earthjustice law firm, on behalf of the Tohono O’Odham, Pascua-Yaqui and Hopi tribes.
“Hudbay’s operations would cause significant, if not catastrophic harm, to our nation’s waters. Hudbay would destroy the network of ephemeral streams on the site, causing ‘irreparable harm to the environment’ and degrading downstream waters,” Earthjustice attorney Stu Gillespie wrote to the Army Corps on March 28.
Gillespie said he hopes that Hudbay or the Army Corps will choose to not start or allow construction until the company gets a Clean Water Act permit.
As for Hudbay’s letter to county flood control officials, Hudbay said it’s submitting that information “for review and comment” purposes only. The Flood Control District has no authority under state law or county codes to prohibit construction or require a floodplain use permit for construction of waste rock disposal areas or tailings dams, Hudbay said.
If any other planned facilities aren’t exempt from county floodplain requirements and would lie within a designated floodplain, Hudbay will request a floodplain use permit for them from the county “at the appropriate time,” wrote Del Rio, vice president for the U.S. and South America operations of Toronto-based Hudbay.
The Flood Control District doesn’t disagree with Hudbay’s stance that tailing dams and waste disposal areas are exempt from permitting, Deputy District Director Eric Shepp responded to Hudbay on March 28. But the district believes other planned development activities on the site are subject to county floodplain management regulations, Shepp wrote.
Shepp also requested more information from Hudbay to meet county requirements for adequate information for the district’s review and comment before construction starts.
Hudbay’s submitted plans “appear to be concept level plans rather than construction plans,” while Pima County codes require submittal of formal construction plans, Shepp wrote.
“This provides the district an opportunity to provide meaningful and substantive comments to ensure the most effective design is considered,” Shepp wrote.
Asked about that by the Star, Hudbay replied, “Hudbay has been corresponding with the Flood Control District and is currently awaiting comments from the District on the plans we have provided.”
Copper World spans 3,430 acres from near the company’s proposed Rosemont Mine site on the east slope of the Santa Ritas to to the historic Helvetia mining area on the west, where copper was removed from the 1880s through the early 1960s. About 1,290 acres will be disturbed by construction of Copper World, Hudbay has said. The Rosemont project is tied up in federal court and on hold.
The company won approval in October from the Arizona State Mine Inspector’s Office for a Copper World reclamation plan. Hudbay has repeatedly praised the Copper World deposit as being of higher grade and lying closer to the ground surface than its Rosemont deposit.
“The initial resource for our Copper World project is larger and at a higher level of geological confidence than we expected at this stage due to the exploration team’s success in discovering several quality deposits through an extensive drill program this year,” said Peter Kukielski, Hudbay president and chief executive officer, in a news release about the site in December.
“The metallurgical testing and mineralogical studies on Copper World are well-advanced,” and the company will release a preliminary economic assessment in the first half of 2022, Kukielski said.
Hudbay affirmed to the Star on Monday that the assessment is scheduled for release on that timetable.
