TUCSON — The U.S. Forest Service will give the public another three months to speak for or against a planned copper mine in the Santa Rita Mountains east of Green Valley and Sahuarita.

But U.S. Rep. Gabrielle Giffords, at the same Tucson press conference, said the ultimate decision of whether to build the copper mine at Rosemont will be an economic decision by the mining company, Augusta Resource.

Giffords said public protests at environmental scoping hearings in Tucson, Green Valley and Patagonia recently encouraged her to seek more time for opponents to mount arguments against the mine.

But under 1872 federal mining laws, it appears the mine probably will be built.

“Mining is an accepted use of  National  Forest  land,” said Jeanine Derby, forest supervisor for the Coronado National Forest at a press conference Friday afternoon.

But Derby said she was “radically neutral on the project.”

She and Heidi Schewel, the local media officer for the Forest Service, appeared at the crowded press conference at Giffords’ Tucson office.

Giffords said she is concerned, as are many citizens, about “the mine’s potential impacts on our water, air and quality of life.”

Many public organizations and elected officials have joined in opposition to the proposed mine.

The Pima County Board of Supervisors also voted 5-0 against the mine.

People have expressed concern about the water that a copper mine would consume.

Under federal law copper mines don’t have to file an application to use all the water they need.

Augusta Resource is currently drilling wells in the Sahuarita area and pumping thousands of gallons of water every day.

Nearby residents have complained their wells are being affected.

With Derby at her side, Giffords said the public scoping process will be extended “from the original 30 days to 120 days,” ending next July 11. There is already an open-house meeting scheduled in Vail on April 5.

Other open-house meetings will be held at Sahuarita and Sonoita.

The most recent open-house meetings permitted no speakers, but people were encouraged to write their comments and leave them with rangers or employees of SWCA, a private consulting company working for the Forest Service.

There will be three public hearings in addition to the open-house meetings in central Tucson, Green Valley-Sahuarita and the Sonoita-Patagonia area.

People will be allowed to speak, and their comments recorded.

Giffords also said the selection process for the environmental impact statement contractor, SWCA, will be reviewed.

“Concerns have been raised about the process employed  by  the  Forest  Service” to select SWCA, she said.