Case Study

Rosemont: A Challenging Path to a World-Class Mine

Early in 2019, after a comprehensive process of consultation and review, Hudbay received the final federal permits for its Rosemont project in Arizona: the Section 404 Water Permit from the US Army Corps of Engineers and approval of the Mine Plan of Operations from the US Forest Service. At that point, Hudbay was ready to embark on developing one of the most environmentally innovative and highly productive low-cost copper mines in the world.

In July 2019, however, the US District Court for Arizona overturned the permits and approvals for the project in an unprecedented ruling, and effectively halted development from moving forward. A strong regulatory regime creates clear criteria for a project to achieve acceptable environmental performance, and in return for meeting these criteria should create predictability for companies with respect to the permitting process and timelines. We believe the Rosemont design included significant investments that more than addressed the regulatory criteria to represent a state-of-the art project, and we are disappointed this did not deliver the corresponding certainty of timelines. Hudbay and the federal agencies are appealing the decision that overturned the federal permits. Since acquiring Rosemont in 2014, we have successfully defended seven lawsuits relating to the project – the first six at the trial court level and the seventh on appeal. Based on decades of established precedent, we are optimistic that we will eventually move forward in developing Rosemont.

Guided by that belief, Hudbay’s Arizona Business Unit continues to look for ways to optimize the project, as well as evaluating other options to advance it. Our intention is still to build a world-class mine at Rosemont, and we will keep stakeholders informed through the process. We are also using insights gained from the Rosemont process to help guide planning for future development at Mason.


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