ADEQ Issues Water Quality Permit for BHP Copper Pinto Valley Mine in Miami

PHOENIX - Arizona Department of Environmental Quality (ADEQ) Director Steve Owens announced that ADEQ has issued a water quality permit for the BHP Copper Pinto Valley Operations open pit mine in Miami in Gila County. The permit, which is technically an amendment to BHP's existing aquifer protection permit (APP) for the mine, provides for resumption of open pit mining at Pinto Valley with development of Slice 6 of the pit. BHP estimates that Slice 6 contains 700 million pounds of copper and would be a 5 ½ year project with potential economic impact to the local economy of $165 million. "This is a strong water quality permit that will protect groundwater in the area, while enabling BHP Copper to continue moving forward toward re-opening the mine as planned," Director Owens said. "Issuance of this permit is another step toward creating much-needed jobs in Gila County while also safeguarding precious water resources." The permit protects groundwater in the area by regulating discharges from the operations at the mine, including the open pit and new Slice 6, waste rock disposal areas, a raffinate pond, one heap leach pad, two pregnant leach solution ponds, a new spillway between the ponds, two active tailings impoundments, and a stormwater management system that is designed to protect facilities regulated by the permit and prevent off-site discharges. Pinto Valley Operations includes a solvent extraction/electrowinning process plant and other infrastructure and support facilities associated with copper mining. The permit sets discharge limits and groundwater quality standards and reduces the discharge of pollutants by requiring BHP Copper to employ appropriate engineering controls and processes at facilities regulated by the permit. The permit also requires BHP Copper to sample seeps and springs located on-site, and to conduct quarterly groundwater monitoring to ensure that water quality has not been affected by operations at the mine. Owens added that his office has worked hard to expedite permits in rural areas, to help support economic growth, while protecting air and water quality. This permit was processed under a new expedited permitting program for water quality permits established by ADEQ in 2006. Last week, Owens announced that ADEQ also has issued the air quality permit for the BHP Copper Pinto Valley mine.