Canada-based base metals miner Hudbay Minerals is set to announce plans for an initial 15-year copper mining operation in Arizona, incorporating the Copper World deposit and an alternative plan for its Rosemont deposit.

The company is nearing completion of a preliminary economic assessment (PEA) for Copper World and will announce its results before the end of next month, it said on Monday.

Early site works are already under way, with initial grading and clearing activities taking place.

The PEA would incorporate a two-phase approach, the first of which would focus on mining portions of Copper World and Rosemont that were located on patented mining claims, Hudbay said, noting that Phase 1 would only require state and local permits. The company would use its private land for processing infrastructure.

The second phase will extend the mine life and incorporate an expansion onto federal lands to mine the entire Rosemont and Copper World deposits. This phase will be subject to the National Environmental Policy Act permitting process.

The company has faced significant opposition to its initial plans for Rosemont, located in the Santa Rita mountains in Tucson, with the project facing several years of permitting delays.

The miner is facing fresh litigation with two groups having provided Hudbay with separate notices last month of intent to bring citizen suits against Rosemont under the Clean Water Act. In each case, project opponents have alleged that Copper World contains jurisdictional waters of the United States (WOTUS) and that Rosemont requires a Section 404 Clean Water Act permit to advance the project.

Hudbay says the Army Corps of Engineers has never determined that there are WOTUS on the site and that the company has independently concluded that none of the dry washes in the area are WOTUS.

In addition to the citizen suits under the Clean Water Act, the same groups subsequently filed motions for a preliminary injunction in the two lawsuits challenging the 404 permit for the Rosemont project. These lawsuits had been stayed following the suspension of the 404 permit in 2019. Hudbay says it in the process of relinquishing the suspended 404 permit and has filed a motion to dismiss these cases as moot on that basis.

The company is still awaiting a decision from the US Court of Appeals for the Ninth Circuit relating to the District Court’s 2019 ruling to vacate the final record of decision (FROD) in respect of the Rosemont project. The FROD was issued by the US Forest Service and is based upon a standalone development plan for the Rosemont project, as set forth in Hudbay’s 2017 feasibility study.