A large industrial development approved last month in unincorporated San Tan Valley has now been confirmed as a hypersonic missile manufacturing and testing facility.
According to the Phoenix Business Journal, California-based Castelion Corporation is the company behind "Project Ranger," a 1,105-acre site located north of Florence Junction — within unincorporated San Tan Valley. Arizona State Land Department documents obtained by the publication identify Castelion as the previously undisclosed developer.
County Approvals Already in PlaceOn October 15, 2025, the Pinal County Board of Supervisors unanimously approved three key land-use requests for the project following unanimous recommendations from the Planning and Zoning Commission:
All three measures passed without any public reference to missiles, defense manufacturing, or Castelion Corporation.
Public Hearings Left Out Key Details
During both Planning and Zoning and Board of Supervisors hearings, the project's attorney, Jordan Rose of Rose Law Group, described it only as a major manufacturing operation expected to become one of Pinal County's largest employers.
At the October 15 meeting, Rose emphasized that "any noxious uses" — including vehicle storage yards, landfills, transfer stations, adult businesses, or prisons were prohibited. However, neither Rose, county staff, nor elected officials mentioned that the end user was a defense contractor or that the site would manufacture and test hypersonic missiles.
Conceptual site plans were presented publicly, but they contained only generic building layouts and infrastructure notes - not the facility's intended purpose.
About Castelion CorporationFounded in 2022 and headquartered in Torrance, California, Castelion is a defense-technology startup specializing in long-range hypersonic strike weapons. The company also operates facilities in Texas.
On October 24, 2025, Castelion announced new integration contracts with the U.S. Army and U.S. Navy for its Blackbeard weapon system, which will be installed on operational platforms and tested through live-fire demonstrations.
In filings with the Arizona State Land Department, the company disclosed plans to store hazardous materials at the San Tan Valley site, including:
Location and AccessThe project site lies south of the Magma Arizona Railroad and Skyline Drive, west of State Route 79. While often described as "north of Florence," the land is in unincorporated San Tan Valley, not within the Town of Florence boundaries.
County documents show plans to extend Skyline Drive east to SR-79 for primary site access and indicate minimal truck traffic - roughly two to three deliveries per week plus outgoing shipments. The project may also reactivate the dormant Magma Arizona Railroad to move materials.
Next Steps
The land, currently owned by the Arizona State Land Department, will be auctioned before construction can begin. Once sold, the developer must secure site-plan approval and obtain all required federal, state, and county permits.
Because the end use involves defense manufacturing and hazardous materials, additional oversight may fall under federal defense, environmental, and transportation regulations.
Regional Impact
If completed, the facility would represent one of the largest industrial investments ever approved in unincorporated San Tan Valley. Officials have said the project could become one of Pinal County's largest employers, though specific job estimates have not been released.
Infrastructure improvements tied to the project — including roadway extensions and possible rail reactivation — could influence future development patterns in the surrounding area.
Background: Arizona's Recruitment Efforts
Earlier this year, Arizona Luminaria reported that U.S. Senator Mark Kelly and the Arizona Commerce Authority had worked to recruit Castelion to the state for a potential site near Tucson. Pima County signed a nondisclosure agreement with the company in 2024, though the final site was instead selected in Pinal County.
What's Next for Residents
While no homes are located within two miles of the site, its scale and purpose have raised questions about transparency and environmental safety. Future public meetings and permitting stages are expected to offer additional opportunities for residents to learn more about how the project may affect traffic, air quality, and long-term land use in unincorporated San Tan Valley.
Sources: Phoenix Business Journal (Oct 30 2025), TechCrunch, Arizona Luminaria, Pinal County Planning & Zoning Commission Records, Arizona State Land Department filings.
Documents Presented at October 15th Board of Supervisors Meeting
Items 17-19 begin at about 2:30:20 in the video below