Another mining company has its eye on the mineral wealth of the Patagonia Mountains.

The Coronado National Forest has recently sent out a scoping notice that indicates it is considering a new request by a multinational mining firm to conduct an exploratory operation 10 miles south of Patagonia.

“OZ Exploration Pty. Ltd, a Delaware corporation authorized to do business in the State of Arizona, proposes to drill seven core holes to test for copper mineralization in the Guajalote Flat and Paymaster areas of the Patagonia Mountains,” wrote Richard Ahern, minerals program manager for the Coronado National Forest, in a letter dated Aug. 18 that gives the public 30 days to respond. “If approved, the proposed action would be completed, including reclamation, in less than one year (about 35 weeks) from the date of approval.”

“This is not a mine. They are just poking around to see what is there,” Ahern told the Weekly Bulletin. He said the notice has not been posted in any newspapers. Instead, Ahern said he has sent out “around 1,000 e-mails.” He said so far response has been minimal.

According to the Standard and Poor’s website, OZ Minerals Ltd. is actually based in Melbourne, Australia and “engages in the exploration, mining, processing, and sale of copper, gold, silver, and other minerals in Australia and Asia.” The company also carries out exploration activities in Australia, Cambodia, Chile, Mexico, and the United States the website says.

The scoping letter said core holes would be drilled to depths of up to approximately 3,300 feet and each drill site is expected to be approximately 75 feet by 75 feet and would include a mud pit or sump with dimension of 5 feet by 10 feet by 5 feet.

“Operations would run 24 hours per day, 7 days per week with crews working two twelve-hour shifts per day,” the letter said.

Access to the project area is being proposed via State Route 82 and Forest Service Roads 82, 61, and 49, also known as Duquesne Road. In addition, approximately 2,000 feet of “temporary, low-standard access road” would be constructed on Forest Service land to provide vehicle access to and from the drill sites.

“Traffic from the junction of Hwy 82 and Duquesne Road to the project site would include initial travel by the road contractor and heavy equipment, followed by travel of the drill-rig pipe truck and several service vehicles,” the letter said. “Daily travel during the estimated 35-week period of drilling would include a crew truck and a service and fuel truck, as needed, for each of the two shifts and multiple trips per day by a water truck.”

The letter said a water truck, with a carrying capacity of 2,500 gallons, could make as many as 10 trips per day to the drilling site depending on drilling conditions, and a commercial vendor would supply water for drilling and dust suppression.

Reclamation plan

According to the letter, the reclamation plan would begin with a “concurrent phase” consisting of plugging of each hole before the drill rig is moved offsite.

“This would be done in accordance with Arizona Department of Water Resources regulations by backfilling with bentonite mud below the water line, filling from the top of the water table to within 20 ft of the surface with a mixture of bentonite drilling mud and drill cuttings, and filling the remaining 20 ft with neat cement. When the drill rig is moved from a site, all equipment and supplies would be removed from the site along with any trash and other non-native materials,” the letter said.

In addition, “post-drilling” reclamation would include filling the mud pits at the drill sites, leveling berms not needed for erosion control, and replanting the site with “native vegetation.” Temporary roads providing access to the drill sites would be recontoured or bermed with additional drainage bars and cutouts to prevent erosion, replanted with native vegetation, and their entrances blocked to obstruct future traffic.

To view a complete version of the scoping, notice visit the Coronado National Forest website.

Written comments on the proposal may be sent by U.S. mail to Richard Ahern, Minerals Program Manager, Coronado National Forest, Supervisor’s Office, 300 West Congress Street, Tucson, AZ 85701; by fax to his attention at (520) 388-8305; and by email to

The Wildcat Silver Corporation, a Canadian-based mining company, has also applied to conduct exploratory drilling on Forest Service land near Patagonia as it develops a plan to construct an open-pit mine. Wildcat’s Hermosa project, also known as the Hardshell project, involves an area just east of Patagonia along Harshaw Road.

Load comments