Arizona Game & Fish Department warns Rosemont mine could pollute protected “Outstanding Arizona Waters”

The Arizona Game & Fish Department (AGFD) is sharply criticizing the Coronado National Forest’s Final Environmental Impact Statement (FEIS) for the proposed Rosemont copper mine stating the Forest Service failed to adequately disclose that the mine may pollute two sensitive waterways that are protected by state law from any degradation.

The AGFD is also raising concerns over seepage from Rosemont’s proposed Dry Stack Tailings Facility polluting downstream waterways, the Forest Service’s failure to require a detailed assessment of the current water quality to serve as a baseline to measure against future potential contamination and “inconsistent and contradictory statements” throughout the FEIS.

The department’s concerns are included in 18 written objections to the FEIS filed with the Forest Service on Feb. 14. The Forest Service must respond to the objections in writing by the end of April.

AGFD states the Regional Forester who is reviewing the written objections “should remand the FEIS back to the Coronado NF Supervisor to resolve these inconsistencies, and require that scientific information supports conclusions in the FEIS.”

The goal of AGFD does not appear to stop the Rosemont copper project from moving forward, but instead for the Forest Service to prepare a more robust FEIS “that fully achieves (National Environmental Policy Act’s) requirements and, if challenged, is upheld in the federal courts.”

Most of the AGFD’s objections focus on the mine’s potential negative impact on the water quality of Davidson Canyon Wash and Cienega Creek, both of which are classified as Outstanding Arizona Waters that are protected by state law from being degraded.

“The Department’s previous comments concerning potential effects of mine waste rock stormwater runoff and tailings seepage on the downgradient watersheds, including the water quality of the Outstanding Arizona Waters in Davidson Canyon, Cienega Creek, rirparian and aquatic species, have not been adequately addressed in the FEIS,” Jim deVos, AGFD assistant director of the Wildlife Management Division states in the 34-page, Feb. 14 letter.

AGFD notes that the FEIS included “new information” from the Coronado National Forest’s environmental consultant that predicts “several heavy metals in the Rosemont stormwater waste rock runoff, including copper, selenium, arsenic, mercury, molybdenum could degrade, or significantly degrade, the existing water quality of downstream watersheds.”

The pollutants, the department states, “are toxic to aquatic species, and mercury and selenium are bioaccumulative in insects, invertebrates, amphibians and fish.”

Despite the finding, the Department states that the FEIS failed “to analyze whether mine runoff would adversely impact waters in Davidson Canyon or Cienega Creek.”

AGFD called the Forest Service’s decision not to conduct the analysis “puzzling” because the Coronado National Forest had earlier acknowledged that it has “the responsibility under NEPA to take a ‘hard look’ at the potential degradation of the downstream Outstanding Arizona Waters.”

AGFD also filed objections related to Rosemont’s plans to use “dry stack tailings” and its failure to analyze and disclose how pollutants from the tailings dump could contaminate downstream waterways.

The Department states that the FEIS incorrectly claims that the mine’s open pit will capture all the seepage from the dry stack tailings. In fact, AGFD points out that Rosemont Copper Company’s own environmental consultants concluded “the majority of the draindown seepage from the Dry Stack Tailings will not be captured by the open mine pit, but will migrate downstream” for 500 years. The seepage from the tailings dump would contain “magnesium, molybdenum, selenium, sulfates, and high levels of total dissolved solids,” AFGD states.

“The Forest,” AGFD states, “has the responsibility to conduct an analysis” of the pollutants in the seepage and their “potential impacts on downstream groundwater and surface water resources and wildlife.”

AGFD also states the FEIS “makes inconsistent and contradictory statements” throughout its discussion on the mine’s impact on groundwater, surface water and seeps and springs.

“The FEIS categorically states in several chapters that the mine will have no effect on water quality in Davidson Canyon or Cienega Creek,” AGFD states. “However, the Forest Service’s consultant predicts that metals in mine waste rock runoff and soil ‘could present antidegradation problems’ in the downstream Arizona Outstanding Waters.”

The Regional Forester’s written response to AGFD’s 18 written objections and about 200 other written objections filed by mine opponents must be completed by the end of April.

The Regional Forester could require the Forest Service to conduct the additional studies and further analyses requested by AGFD and others for inclusion in a revised FEIS. Doing so would delay the issuance of a Final Record of Decision on whether to allow Rosemont to dig the mile wide, half-mile deep mine and dump its toxic mine wastes on the Coronado National Forest.