Several mitigation measures for the proposed Rosemont copper mine near Tucson, AZ were dropped by the U.S. Fish and Wildlife Service after the U.S. Forest Service and the mine’s developer Hudbay Minerals Inc. objected to them.
The Arizona Daily Star obtained details of the early measures and the Forest Service’s objections through the federal of Freedom of Information Act and reported backfilling the openpit, kicking cattle off riparian areas and protecting against invasive, non-native species for 150 years were among the measures that were dropped. The measures would have been mandatory but were excised from the wildlife service’s final opinion for the mine, published in April 2016.
Another since-pulled measure in the November 2015 draft, which was never publicly released, would have required Rosemont to ensure that the San Rafael Valley and Upper Santa Cruz River watersheds — an area critical to the survival and recovery of an endangered fish called the Gila chub — “be secured and maintained as a wholly or nearly wholly native community over the next 150 years.” Similar measures were planned for the threatened Chiricahua leopard frog and the endangered Gila topminnow and desert pupfish.
In all, the measures were targeted to protect seven of the 12 imperiled species known to live on or near the mine site. The other species were the endangered Huachuca water umbel, a plant, and the threatened Northern Mexican gartersnake and Western yellow billed cuckoo.
For the final biological opinion, the two agencies and the mining company agreed on three other conservation measures — less expensive, less sweeping and less controversial:
• A $3 million invasive species control program would control non-native catfish, bullfrogs, sunfish and crayfish and non-native plants in the Cienega Creek and San Rafael Valley-Santa Cruz River watersheds. It isn’t required to be effective for 150 years.
• A full-time staff biologist would monitor the effectiveness of mitigation and conservation measures, including 4,800 acres of land purchases Rosemont has agreed to make outside the mine area.
• A $1.25 million program would replace riparian habitat damaged by the mine and improve other habitat to benefit the endangered Southwestern willow flycatcher and the yellow-billed cuckoo.
The biological opinion must be finished before the Forest Service and the Army Corps of Engineers make final decisions on whether the mine can be built. The agencies have said they’ll make their decisions this summer, with the Corps’ decision possible within weeks.