Casa Grande planning staff has recommended approval of three requests by Ivanhoe Electric for their proposed Santa Cruz Copper Project, a major underground mining operation planned for about 3,300 acres north of Gila Bend Highway between Montgomery Road and Russell Road. The site, originally approved in 2006 as the Legends Planned Area Development for mixed-use residential development with approximately 11,000 residential units, never came to fruition due to numerous issues which included water resource challenges.
The requests include removing Indian Valley Road and Clayton Road from the planned roadway network within the project boundary, as these roads will need to be closed for mining operations. The company’s primary access to the site will be from State Highway 84 at Midway Road, with a secondary limited access from W. Korsten Road to the north.
The project is located in Arizona’s prolific mining region, where over 35 million tonnes of copper have been produced since 1980, representing about 65% of total US production.
During public comments, Kevin Evans, who represents Valvista Marketplace’s farming operations to the south, raised concerns about how the mining project might affect local water supplies, roads, and environmental conditions. Evans specifically questioned the potential impacts on farming operations and sought details about how the extracted ore would be processed and transported.
Kami Ballard from Ivanhoe Electric explained that while the project is on private land, it must still undergo extensive permitting processes with various agencies. These will include permits for water quality protection, aquifer protection, dewatering, and air quality. Each of these major permits will require public notification and meeting processes before mining can begin.
John Gillespie, an attorney representing Ivanhoe Electric, emphasized the project’s economic benefits, projecting $9.2 billion in economic activity over the mine’s lifetime. The project is expected to create 750 jobs, with 550 being direct positions with Ivanhoe Electric. He highlighted the company’s commitment to environmental conservation, including setting aside 400 acres as a protected habitat for burrowing owls.
The mining operation will use an underground method called “long hole stoping” rather than open pit mining. Stoping is the process of extracting the desired ore or minerals from an underground mine, leaving behind an open space called a stope. According to Ballard, the Santa Cruz project’s method involves putting rock back into the ground after extraction to maintain stability and prevent surface subsidence. Unlike open pit mining, this underground method minimizes surface disruption.
The staff recommendations include updating development guidelines and setting specific height limits for waste rock storage areas. The project timeline shows construction beginning in fall 2025, with mining operations starting in 2028 or 2029. Once operational, the facility plans to extract between 15,000 to 20,000 tons of rock daily for approximately 20 years, followed by a five-year site restoration period.
The project site provides access to rail, interstate highways, and electric transmission lines. Ivanhoe Electric plans to generate 70% of the project’s required electric power through onsite renewable energy infrastructure to minimize carbon emissions.
The project will go before the City Council for final consideration at their January 21, 2025 meeting.
