The Rosemont Project has re-evaluated its operation and made changes to its operations that affect emissions and predicted impacts. These include the following:
- A reduction in the number of blasts that can occur on a daily basis from two to one.
- Limiting blasting events to occur from Noon to 4:00 in the afternoon, and
- Reduction in the average annual operating hours of its haul trucks from 92% availability (8,060 hours) to the more realistic value necessary to meet its mining plan of 6600 hours per truck.
The modeling presented herein incorporates the changes in emissions due to the changes in operations and addresses the comments and recommendations made by the Forest Services. The remaining sections of this report present the air dispersion modeling methodology and modeling results for the Rosemont Project.
Applied Environmental Consultants. 2011b. Rosemont Copper Company Revised AERMOD Modeling Report to Assess Ambient Air Quality Impacts. Prepared for SWCA Environmental Consultants. Tempe, Arizona: Applied Environmental Consultants. April 4.