By Chase Kamp
Southeast Valley Ledger
At its regular meeting on Aug. 6, 2012, the Florence Town Council passed an ordinance banning in-situ mining and other operations that use large amounts of sulfuric acid. The ordinance classifies the use of sulfuric acid as a nuisance, arguing the chemical poses a danger to residents.
The measure is in reaction to Curis Resources and its proposed Florence Copper Project, which utilizes an in-situ mining process involving the injection of a diluted sulfuric acid solution into underground copper-bearing zones.
According to Curis, the in-situ copper recovery solution is 99.7 percent water and one-third of 1 percent sulfuric acid by volume. The solution is injected about 400 to 1,200 feet below the surface, where it dissolves the copper ore and is then extracted back to the surface.
The ordinance is only the most recent move by the Town in opposition to the Florence Copper Project. The Council previously voted against a General Plan amendment proposed by Curis in Nov. 2011.
Rita Maguire, senior legal and government affairs advisor for Curis Resources, argued sulfuric acid is a common substance used by a wide variety of businesses. “This product is being transported by trucks and trains traveling through Florence every day,” Maguire wrote.
Maguire’s statement said the ordinance was “special legislation” targeted only at Curis and was a violation of equal protection laws. “The town, by this action, is attempting to take private property unfairly and under a thin pretext,” she wrote.
Florence Deputy Town Manager Jess Knudson argued the law applies to in-situ mining or any other business, with an exception for agricultural uses that uses large quantities of sulfuric acid.
“While this law affects Curis Resources LTD., the law does not solely affect their business,” Knudson said.
He said the town was confident about the ordinance “as means to protect the health, safety and welfare of our residents.”
The Arizona Department of Environmental Quality is currently evaluating the Florence Copper Project’s application for a temporary aquifer protection permit. If granted, the permit would allow a pilot test project to proceed on a small portion of Arizona State Trust land.
ADEQ officials said many of its requirements for such permits have overlap with federal Environmental Protection Agency regulations.
Maguire said the copper project will be thoroughly vetted and evaluated by independent governmental agencies.
“All operations will be conducted with the utmost regard for the health, safety, and welfare of the community,” Maguire wrote. “The thorough evaluation process and review must take precedence over any local interference in the state and federal agencies’ regulatory decisions.”