WINONA — Winona County commissioners on Tuesday approved a conditional use permit for the first operation to exclusively mine frac sand in the southeastern Minnesota county.

Opponents accused the board of rushing to make a decision while residents appeal an earlier board decision not to require a full environmental review of the proposed mine.

“You need to slow down and think about what’s in the best interest of the county and the citizens of the county, not just what’s in the best interest of the mining industry,” Winona County resident Joe Morse told commissioners.

The 3-2 vote came after the board rejected a motion to suspend action on the permit until after a state appeals court can hear a group of area residents’ appeal of an earlier board decision to not require a full environmental review, KAGE Radio reported.

Board Chair Wayne Valentine, who voted to approve the permit, said the county’s land-use ordinance allows the operation.

“I think as a board we have really attempted to listen to your concerns. As a result of that, we’ve attached almost 38 conditions to that permit. We have heard your concerns, we appreciate your comments,” Valentine said.

But Commissioner Jim Pomeroy said the board needed to slow down.

“What are our limitations? What are our limiting factors? A concern that I have is, we’re all of a sudden going to have this ‘uh-oh,’ moment. It’s going to be too late. It’s tough to go backwards on permits. Do we think five mines would be good, or 50, or 100?” said Pomeroy, who opposed the permit.

The initial application for the 20-acre Nisbit mine in Saratoga Township was denied after the county imposed a moratorium on frac sand mining in 2012. A second application was submitted after the moratorium expired.

County commissioners voted in April to pass on an intensive environmental review sought by some residents. That vote came after the Minnesota Pollution Control Agency and the Minnesota Department of Health called for the project to be added to a more sweeping environmental review of several mines in both Winona and Fillmore counties.

Nisbit mine operator Jeff Broberg said that the mine could begin operating later this month or in July.

After the vote, Jim Gurley of Winona Area Citizens Concerned About Silica Mining said in an email the proposed mine will generate up to 280 truck trips per day, “and will set an unfortunate precedent.”

The oil and gas industry uses silica sand in the hydraulic fracturing process to unlock underground energy supplies. The sand underneath parts of western Wisconsin and southeastern Minnesota has the ideal shape, hardness and purity for the process. But mining the sand has generated opposition because of the impacts on the environment, health and public infrastructure such as roads and bridges. Supporters say it creates jobs and fosters energy independence.