The entrance to the Rosemont Mine from Arizona 83 at the foot of the Santa Rita Mountains southeast of Tucson.

The company building the Rosemont Mine will start archaeological work on the $1.9 billion project next month along a planned utility line corridor from Sahuarita to the mine site in the Santa Rita Mountains.

That’s the first of four construction-related projects that Hudbay Minerals plans to undertake over the next two months, according to a transcript of a May 14 phone conference among lawyers for all parties involved in the five federal lawsuits regarding the mine project.

But while opponents are seeking an injunction to stop the mine from being built, they aren’t trying to stop these projects. They’re located away from the proposed mine site and wouldn’t be built on any federal land, for instance. So for one, the tribes that are seeking an injunction don’t think they’ll cause “irreparable harm” to their interests.

The construction projects that would cause concern among the tribes and environmental groups aren’t scheduled to start until mid-July or early August at the earliest. By then, U.S. District Judge James Soto said he hopes to rule on the opponents’ injunction request, the status conference transcript shows.

One of these bigger projects involves drilling 36 exploratory holes on the mine site of a few hundred to up to 3,000 feet deep. Another will be work on a water line along a utility corridor from Sahuarita over the Santa Ritas to the mine site.

Here are the specific projects that Hudbay attorney Norm James told the judge would be starting in the next two months:

  • In June, the company will start what James called “archaeological clearance work” on private and state land along the utility line corridor. The work will be done on archaeologically historic sites, many of which are old mining sites including the Helvetia area west of the Santa Ritas, James said. Prehistoric sites of importance to the three Indian tribes seeking the injunction won’t be worked on in that time, said James, the transcript shows.
  • Work on drilling water supply wells in the Sahuarita area, on private land, will start sometime after mid-July. The company won’t start work on building the water line in the utility corridor until it can obtain additional clearances from the Army Corps of Engineers beyond the federal Clean Water Act permit the Corps approved in early March. That also will start sometime after mid-July.
  • Hudbay will start work in July on upgrading two intersections along Arizona 83 on the east side of the mine project area.
  • At the Sonoita Creek Ranch mitigation site that’s owned by Hudbay, the company plans to start work, probably in July, on replacing fencing and conducting plant salvage and transplanting activity.

The company has said it plans to invest about $144 million on building Rosemont in the first year of construction, and finish construction work and start mining by sometime in 2022. The Indian tribes and environmental groups are seeking the injunction to prevent construction of any significant projects from starting until the judge can rule on the merits of the suits.


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Contact reporter Tony Davis at tdavis@tucson.com or 806-7746.