An Army Corps of Engineers decision could bolster a mineral company’s legal argument that a washes at a mine site in Arizona are not covered by the Clean Water Act.

An Army Corps of Engineers decision could bolster a mineral company’s legal argument that a washes at a mine site in Arizona are not covered by the Clean Water Act. (Hudbay Minerals/Facebook)

(Tribune News Service) — A top U.S. Army official reversed himself on a key decision — a reversal that could bolster Hudbay Minerals Inc.’s legal argument that the washes on its long-delayed Rosemont Mine site don’t merit federal regulation.

Assistant Army Secretary Michael Connor wrote an August 2022 memo withdrawing a decision that had overruled an earlier decision freeing the Rosemont site’s washes from federal Clean Water Act protection. Connor’s latest decision appears to restore a 2021 Army Corps of Engineers decision that the washes at the Rosemont site aren’t covered by the Clean Water Act.

Despite that, late Friday an Army Corps of Engineers spokeswoman referred in an email to a possibility of enforcement action against Hudbay’s plans to grade washes inside an area of the Santa Rita Mountains south of Tucson that’s covered by a now-suspended Clean Water Act permit for the Rosemont Mine.

“Hudbay has told us they intend to proceed with filling in washes that fall within the permit areas. We are coordinating with EPA on enforcement. Enforcement is discretionary,” Dena O’Dell, a spokeswoman for the Corps’ Los Angeles District, said in the email, without elaborating.

The Corps has already said the EPA was conducting a law enforcement investigation of Hudbay’s grading activities. EPA has declined to comment on it or acknowledge it’s happening.

The Corps hasn’t responded to questions from the Star about the apparent discrepancy between Connor’s August 2022 decision and the agency’s increasingly aggressive actions regarding Hudbay since then, including a mid-January order that the company stop work on washes lying within the Clean Water Act permit area.

Hudbay: Corps lacks authority over site

Hudbay officials have said repeatedly they don’t believe the Corps has any authority over the site.

That’s partly because of the agency’s earlier decision waiving jurisdiction over the Rosemont site, and partly because the company formally surrendered its permit almost a year ago, the company said.

The Corps, however, hasn’t accepted the validity of Hudbay’s permit surrender, although a federal judge did that in a ruling in May 2022 in refusing an effort by mine opponents to stop Hudbay’s grading of washes in that area.

The Corps, which Connor oversees, had decided in March 2021 that it no longer had any authority over the Rosemont washes. Until then, the agency had relied on a decade-old, preliminary determination asserting its jurisdiction over the washes, which the company proposing the Rosemont Mine had voluntarily accepted.

That earlier, preliminary determination of Corps ‘ jurisdiction was a basis for its March 2019 issuance of a Clean Water Act permit, authorizing the mining company to deposit dredged and fill material into those washes as part of its construction work.

Work on Copper World project

Hudbay has been grading and clearing private land on the west slope area of the Santa Rita Mountains on and off since April 2022, for what it says are future waste rock and tailing disposal areas for its Copper World project. The company owns 4,500 acres on the east and west slopes of the Santa Ritas on which it plans to build four open pits for mining copper and numerous other facilities for processing and other activities.

One of the pits would occupy the same area originally proposed for the Rosemont open pit. With the Rosemont Mine itself now on hold due to an unfavorable federal court ruling, Hudbay has renamed that pit the East Pit.

The Clean Water Act permit area was intended to cover only the original Rosemont Mine site. But it also includes part of the west slope area now due to be mined by Copper World, including a utility corridor through which electricity and water would be delivered to the mine site from the Sahuarita area.

The August 2022 memo outlining Connor’s policy reversal came to light after the Corps issued the stop work order in mid-January 2023. Hudbay replied at the end of January that it did not believe it is legally bound to comply with the order.

Friday, in a statement released to the Star , the mining company said it agrees with Connor’s most recent decision and that his earlier decision of June 2022 “contradicted established policy and past practice.”

The company also said it believes the Corps lacks authority over that area because the Corps only has jurisdiction over “Waters of the U.S.” Legally, those are rivers, washes and other water courses deemed environmentally and biologically significant enough to merit federal protection.

“There is no credible evidence that the dry washes on the Copper World site are” Waters of the U.S., Hudbay said. “To the contrary, Hudbay has demonstrated that they are not ... and shared this analysis with the ( Department of Justice, the Army Corps, tribes, and environmentalists) in April 2022.

“Hudbay has studied the ability of the dry washes on the west side to transport contaminants downstream by analyzing stormwater, sediment, and plant samples. These studies show that material from the site is generally only transported 7-8 miles through the flat sandy washes,” the company said in its written statement.

Federal agencies require the existence of a significant connection between a development site’s normally dry washes and a navigable waterway for the washes to come under federal control. Hudbay said the nearest downstream navigable water is the Colorado River, near Yuma, over 350 miles away.

The Corps and EPA, however, have designated sections of the much closer Santa Cruz River as navigable.

Santa Cruz River role debated

Stu Gillespie, an attorney for three tribes fighting the mine, has sent the Corps two documents making the case that the washes at the original Rosemont site and the larger Copper World site do qualify as “Waters of the U.S.” One is a report the tribes commissioned laying out such arguments. Another is an EPA meno, from 2021, criticizing the Army Corps’ decision that year that the Rosemont washes don’t qualify as “Waters of the U.S.”

Mark Murphy, a scientist hired by the tribes, concluded that the Rosemont-area washes, “both individually and in combination with similarly situated streams, have a significant nexus” with the Santa Cruz.

Murphy’s “conclusion is based on an extensive review of the scientific literature, field observations, on-the-ground data, and watershed modeling. His report summarizes the extensive scientific literature on ephemeral streams and their role in maintaining the Santa Cruz River’s ecological integrity,” Gillespie wrote to the Corps in December.

In response, Corps spokeswoman O’Dell told the Star, late Friday, “The Corps is evaluating the information provided by the tribes concerning the March 2021” decision waiving authority over the Rosemont washes.

“No decision has been made yet to reevaluate” its determination, she said.

Corps on ‘very shaky legal grounds’

The final, legal impact of Connor’s August 2022 decision on Hudbay’s activities remains unknown, as are Hudbay’s actual grading plans.

The Corps hasn’t responded to questions from the Star about what authority it has to stop work in the Rosemont permit area, in light of Connor’s August 2022 decision.

In Hudbay’s response to the Corps’ stop work order, company executive Javier Del Rio said it has no plans for work affecting washes covered by the Corps permit until Monday, Feb. 27, at the earliest. Asked last week by the Star if it now intends to start grading and clearing in those areas, Hudbay replied only, “We are in frequent communication with the Corps.”

A Vermont-based environmental law professor, Patrick Parenteau, told the Star last week that the Corps is on “very shaky legal grounds” in ordering Hudbay to stop work at Copper World because of Connor’s August 2022 restoration of the Corps’ earlier decision waiving authority over the Rosemont site.

“They flipflopped,” said Parenteau, of Vermont Law School.

He cited an Army Corps “Safe Harbor” guideline that’s been on the books for 20 years. It says a jurisdictional decision like the one the Corps made for Rosemont in 2021 is valid for a minimum of five years “unless new information warrants revision of the determination before the expiration date.” Connor cited that policy in his August 2022 memo.

That guideline isn’t a formal regulation, Parenteau said. But a 2016 U.S. Supreme Court ruling said that such a determination “is a binding agreement.”

When “the feds make this kind of representation for private parties, they’re entitled to rely on it,” the professor said, speaking of an agency decision waiving jurisdiction over a development site.

He said the Corps can go to court to assert it no longer considers a jurisdictional decision valid, or environmentalists could sue to have it overturned.

But “the cease and desist order means nothing. You need a court order to stop clearing of washes,” Parenteau said. Without it, Hudbay can refuse, he said.

Bui if the Corps were to go to court and win on this case, “they can tack on penalties on Hudbay to the tune of $55,000 per day for every day they are in violation of a cease and desist order,” Parenteau said.

Hudbay has to be certain it doesn’t have to obey a cease and desist order, he said, adding, “If they are wrong ... they are going to pay big time.”

(c)2023 The Arizona Daily Star (Tucson, Ariz.)

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