A little-known federal rule played a key role in killing several tough mitigation measures that the U.S. Fish and Wildlife Service originally wanted to impose on the proposed Rosemont Mine.

Known as the β€œminor change” rule, it allows the wildlife service to require only minor changes in a proposed project unless the project is expected to jeopardize the existence of an endangered or threatened species.

Otherwise, changes can’t alter β€œthe basic design, location, scope, duration, or timing of the action,” the rule says.

In a Draft Rosemont Biological Opinion last November, the wildlife service had placed measures that would have required backfilling the project’s open pit or another evaporation control effort, detailed invasive species control programs lasting up to 150 years and removal of livestock from several riparian areas.

After the Forest Service objected to the measures, the wildlife service killed them, partly because they weren’t minor changes. They didn’t appear in the Final Rosemont Biological Opinion that was published in late April 2016.

The biological opinion concluded that the mine wouldn’t jeopardize or illegally destroy habitat for the imperiled species.

The original measures and those ultimately approved are aimed at limiting or compensating β€œtake” β€” a legal term for killing, harm or harassment of imperiled species, all illegal acts unless approved in advance by the wildlife service.

Asked why the wildlife service first pushed for tough measures only to withdraw them later as not meeting the minor change rule, the agency’s Steve Spangle said, β€œWe knew we were pushing the envelope and we were probably going to get a lot of pushback and we did. β€œWe often don’t contemplate what is or is not a minor change and we let the agency tell us what a minor change is, or is not.”

The minor-change rule, on the books since 1986, drew criticism from County Administrator Chuck Huckelberry, who said a technicality should not be a pathway to avoiding tough mitigation measures.

β€œIf we have a system or a rule or a policy that prevents substantive mitigation, it’s simply wrong,” Huckelberry said.

But Vanderbilt University law professor J.B. Ruhl said it’s not the wildlife service’s role to alter a new facility’s design or location.

β€œWhy would we want a biology agency tinkering with, say, highway or reservoir design?”


Become a #ThisIsTucson member! Your contribution helps our team bring you stories that keep you connected to the community. Become a member today.