It has long been known that an oxide copper deposit lies buried just across the Gila River from the Town of Florence, Arizona. Now, Curis Resources, a Canadian company, proposes to extract the copper, not by digging a mine, but by in-situ leaching. This process involves pumping a weak acid solution (about the same acidity as vinegar) into the ore zone to dissolve the copper minerals and recovering the solution with extraction wells. The copper-laden solution will then go through a solvent extraction/electrowinning (SX/EW) process to produce metallic copper.
The map below shows the location of the project and the surrounding countryside. Notice that the immediate surrounding land is either desert or agricultural.
The mining project is being opposed, not by environmentalists, but by real estate developers. The developers want to do this:
The Real Estate developers are concerned that the mining operation will detract from the desirability of their plans. They also allege that water quality will be impacted. The Real Estate developers have formed a group called “Protect Our Water Our Future.” See that link for their side of the story.
Curis Resources claims that because the copper deposit occurs below a clay layer, the aquifer will be protected and the acidic copper-laden solutions will be contained. That is according to an extensive hydrological study. Also they will have a network of monitoring wells.
Curis Resources says that “Over a 17-year life-of-project, the Florence Copper Project has the potential to directly and indirectly support 2,090 jobs in the United States, including: 250 jobs in the Town of Florence; 370 jobs in Pinal County; and 1,090 jobs in the State of Arizona. Personal income earned by Florence area residents as a result of the Florence Copper Project is expected to total more than $106 million over the life of the project.” Curis goes on to say, “direct and indirect economic contributions will total more than $290 million. This includes $136 million in local government revenues, $47.6 million in local business revenues and more than $106 million in personal income.”
To see the Curis Resources side of the story visit their main website here.
Among the Curis data is a community presentation which includes how the area will look during operations and after operations, the economic impact, and the water concerns, see here.